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Maintaining Group Integrity Improves Sow Performance

In group-housed sows, when similar groups of sows are maintained throughout the gestation period, aggression between groups is reduced, and the culling rate is reduced due to non-productive parameters, increasing the sows' lifetime productivity.

Researchers at the Prairie Swine Centre in Saskatchewan, Canada studied aggression and injuries resulting from grouping sows after breeding.

Searching for methods to reduce aggression, sows were regrouped within a few days of breeding, using five experimental social groups.

Groups contained 16 bred sows. All animals had previous experience in group housing with an electronic sow feeder. Sows were regrouped at 11 days after breeding and placed in a mixing pen on 80 sq. ft. of partially slotted floor.

Each group consisted of approximately equal numbers of Parity 1-2 sows and Parity 3-6 sows. Less than 50% of all penmates within the respective groups were familiar, having shared a pen during the previous gestation.

The five treatment groups included:

  • Control: Group of sows formed as above;

  • Familiar: Sows from the same previous gestation group;

  • Dominant: Standard group of sows and three socially dominant animals that were large (Parity 5 or higher), housed together for at least six weeks, and well acquainted with the mixing pen;

  • Protected: Standard group of sows, but provided with seven free-access half-stalls to offer protection to head and shoulders; and

  • Exposed: Standard group of sows, except these sows were weaned directly into the mixing pen and held there for 48 hours before being moved to the breeding stall.

After regrouping, saliva samples and data on aggression and injuries were collected.

Scores for aggression and injuries among the five social management treatments are detailed in Table 1. The “familiar” treatment, where group integrity is maintained, appears to provide the best opportunity for reducing aggression. Researchers believe that the relatively short fights that occurred among familiar sows probably represented reinforcement of social position rather than the establishment of new hierarchy.

In the “dominant” group, the presence of three older animals from a well-established social order produced fewer aggressive events, particularly on the first day of group formation. The concept behind this treatment is that sows would avoid aggression when in the presence of a clearly dominant individual.

The “exposed” treatment, where sows had spent 48 hours together after weaning, but before being placed in stalls for breeding, did not reduce the incidence of aggression compared to the “control” group, except on the first day. But the level of injuries was reduced.

Researchers noted the short period of pre-exposure used in this study may have only provided a weak social order that required additional establishment after the subsequent regrouping.

This study confirmed other reports showing the ineffectiveness of protective stalling on the aggression among regrouped sows, as in the “protected” group.

No differences were observed in overall salivary cortisol concentrations — a measure of stress levels — among the five treatment groups (Table 1).

However, there were differences in cortisol levels on different days, with the lowest concentration prior to regrouping, and the highest levels on all the days following regrouping (Table 2).

In conclusion, maintaining sows in similar groups from gestation period to gestation period increases the odds of reduced aggression, compared to the other regrouping strategies tested.

But this method would not always be practical. Having dominant sows within the group tended to reduce aggression and injuries on the first day following regrouping. A similar trend was found when sows were exposed to each other before breeding. Protection during regrouping didn't prevent aggression or injuries.

Researchers: H.W. Gonyou and S.M. Hayne, both of the Prairie Swine Centre (PSC). Contact Ken Engele of the PSC by phone (306) 373-9922, fax (306) 955-2510 or e-mail [email protected].

Sow Behavior Cited in Most Crushing Losses

Variation in sow behavior may be more important than piglet behavior in trying to reduce crushing losses the first 72 hours of the piglet's life, according to a research study from Iowa and Texas animal scientists.

Preweaning piglet crushing losses cost an estimated $100 million/year.

Better understanding of the behavioral consequences that piglets and sows engage in prior to crushing may help develop system designs that enhance the well-being of the compromised piglet.

This study compared behavior (nursing) and postures (active and inactive) for piglets during the first 72 hours after farrowing when housed in an outdoor farrowing hut.

No differences were found in the behavioral activities of outdoor, loose-housed piglets that resulted in death by crushing in the first three days after birth. Therefore, researchers concluded, the sows' behavior is a more significant cause of piglet crushing than variation in piglet behaviors.

A plastic shed inside the central hub area of the farrowing pasture housed four, time-lapse video recorders to capture farrowing activities inside four farrowing huts.

Eight PIC Camborough-22 litters were used for behavioral comparisons for piglets in a litter where the dam killed a piglet or did not kill a piglet over the first 72 hours after farrowing.

Researchers: J.R. Garvey, A.K. Johnson, A.J. Holliday, L.J. Sadler and K.J. Stalder, all of Iowa State University, and J.J. McGlone of Texas Tech University. Contact Johnson by phone (515) 294-2098, fax (515) 294-4471 or e-mail [email protected].

Group Size at Loading Is Insignificant

A study at the Prairie Swine Centre in Saskatchewan, Canada compared handling attributes, stress responses and meat quality of pigs from conventional and large group auto-sort pens marketed through the same facilities.

A total of 240 market hogs raised in conventional small groups (16-18 pigs/pen) or in large groups with auto-sort facilities (250 pigs/pen) were marketed over 10 days. Pigs were loaded in groups of four up a ramp onto a trailer. Transportation took 45 minutes to the packing plant and lairage was about four hours.

Behavioral and physiological measures were taken prior to, during and after the handling and transport process. Loins from the animals were assessed 24 hours after slaughter.

In general, it took 50% longer to load pigs from small groups. The need to use electric prods was similar for both groups (Table 1).

Differences observed in heat balance variables (temperatures, skin color and breathing) were early in the handling process, with an increase in rectal temperature after removal from the pen, and an increase in ear temperature once loaded on the trailer, for the pigs from the small group (Table 2).

Cortisol levels, reflective of acute stress, increased about three-fold from handling in the barn to after unloading at the plant, equally present in both large and small groups (Table 2).

Meat quality differences were evident between the two groups. Pigs from small groups had a higher degree of marbling and higher light reflectance (L*), but also a redder color (a*), shown in Table 3.

Other meat quality scores, such as pH, color and Japanese color, suggest there was slightly less response to stress in large group pigs.

Specific project funding was provided by the National Pork Board.

Researchers: S.M. Hayne, D.L. Whittington and H.W. Gonyou, all of the Prairie Swine Centre. Contact Ken Engele by phone (306) 373-9922, fax (306) 955-2510 or e-mail [email protected].

Animal Welfare

Group Size at Loading Is Insignificant

A study at the Prairie Swine Centre in Saskatchewan, Canada compared handling attributes, stress responses and meat quality of pigs from conventional and large group auto-sort pens marketed through the same facilities.

A total of 240 market hogs raised in conventional small groups (16-18 pigs/pen) or in large groups with auto-sort facilities (250 pigs/pen) were marketed over 10 days. Pigs were loaded in groups of four up a ramp onto a trailer. Transportation took 45 minutes to the packing plant and lairage was about four hours.

Behavioral and physiological measures were taken prior to, during and after the handling and transport process. Loins from the animals were assessed 24 hours after slaughter.

In general, it took 50% longer to load pigs from small groups. The need to use electric prods was similar for both groups (Table 1).

Differences observed in heat balance variables (temperatures, skin color and breathing) were early in the handling process, with an increase in rectal temperature after removal from the pen, and an increase in ear temperature once loaded on the trailer, for the pigs from the small group (Table 2).

Cortisol levels, reflective of acute stress, increased about three-fold from handling in the barn to after unloading at the plant, equally present in both large and small groups (Table 2).

Meat quality differences were evident between the two groups. Pigs from small groups had a higher degree of marbling and higher light reflectance (L*), but also a redder color (a*), shown in Table 3.

Other meat quality scores, such as pH, color and Japanese color, suggest there was slightly less response to stress in large group pigs.

Specific project funding was provided by the National Pork Board.

Researchers: S.M. Hayne, D.L. Whittington and H.W. Gonyou, all of the Prairie Swine Centre. Contact Ken Engele by phone (306) 373-9922, fax (306) 955-2510 or e-mail [email protected].

Table 1. Assessment of Handling of Pigs from Large and Small Groups During the Loading Process

  Group Size
Large Small
Level of encouragement1 2.83 2.90
Number of shocks 8.30 12.03
Duration of loading, seconds 52.58 78.71
1Scores are 1 (board only); 2 (board, slap and yell); 3 (prod).

Table 2. Physiological Data of Pigs from Large and Small Groups During Various Stages of the Marketing Process

  Group Size
Prehandling (Barn) Truck Plant
Large Small Large Small Large Small
Ear Temp, F° 93.2 94.1 90.0 92.9 90.9 92.3
Rectal Temp, F° 102.6 103.1 104.0 104.2 39.1 102.4
Cortisol, nmol/L1 11.4 10.4 - - 31.8 27.1
Breathing Score2 1.0 1.02 1.08 1.1 1.07 1.04
Skin Score3 1.01 1.11 1.20 1.21 1.38 1.33
1Nmol/L refers to nanomoles/liter, which expresses the concentration of cortisol found in saliva.
2Breathing score (1-4) refers to 1 = no signs of heavy breathing; 2 = mouth open; 3 = rapid breathing; 4 = breathing sounds very raspy and labored.
3Skin score (1-4) refers to 1 = no signs of skin discoloration; 2 = skin is slightly pink; 3 = red and white areas visible on pig's skin; 4 = very distinct red and white blotches visible on pig's skin.

Table 3. Meat Quality Assessment of Pigs from Large and Small Groups

  Group Size
Large Small
pH 5.75 5.71
Texture1 3.36 3.25
Color2 3.43 3.24
Marbling3 2.51 2.71
L* (lightness) 51.8 53.4
a* (redness) 2.60 2.95
b* (yellowness) 10.25 10.18
Japanese color 3.45 3.36
Drip loss, % 9.74 9.88
1Texture rating 1: Pale, soft and exudative (PSE); 5: Dark, firm and dry (DFD).
2Color (1-6) 1: pale/gray white; 6: dark purplish red.
3Marbling (1-10) 1: absence of marbling; 10: heavy marbling.

Sow Behavior Cited in Most Crushing Losses

Variation in sow behavior may be more important than piglet behavior in trying to reduce crushing losses the first 72 hours of the piglet's life, according to a research study from Iowa and Texas animal scientists.

Preweaning piglet crushing losses cost an estimated $100 million/year.

Better understanding of the behavioral consequences that piglets and sows engage in prior to crushing may help develop system designs that enhance the well-being of the compromised piglet.

This study compared behavior (nursing) and postures (active and inactive) for piglets during the first 72 hours after farrowing when housed in an outdoor farrowing hut.

No differences were found in the behavioral activities of outdoor, loose-housed piglets that resulted in death by crushing in the first three days after birth. Therefore, researchers concluded, the sows' behavior is a more significant cause of piglet crushing than variation in piglet behaviors.

A plastic shed inside the central hub area of the farrowing pasture housed four, time-lapse video recorders to capture farrowing activities inside four farrowing huts.

Eight PIC Camborough-22 litters were used for behavioral comparisons for piglets in a litter where the dam killed a piglet or did not kill a piglet over the first 72 hours after farrowing.

Researchers: J.R. Garvey, A.K. Johnson, A.J. Holliday, L.J. Sadler and K.J. Stalder, all of Iowa State University, and J.J. McGlone of Texas Tech University. Contact Johnson by phone (515) 294-2098, fax (515) 294-4471 or e-mail [email protected].

Maintaining Group Integrity Improves Sow Performance

In group-housed sows, when similar groups of sows are maintained throughout the gestation period, aggression between groups is reduced, and the culling rate is reduced due to non-productive parameters, increasing the sows' lifetime productivity.

Researchers at the Prairie Swine Centre in Saskatchewan, Canada studied aggression and injuries resulting from grouping sows after breeding.

Searching for methods to reduce aggression, sows were regrouped within a few days of breeding, using five experimental social groups.

Groups contained 16 bred sows. All animals had previous experience in group housing with an electronic sow feeder. Sows were regrouped at 11 days after breeding and placed in a mixing pen on 80 sq. ft. of partially slotted floor.

Each group consisted of approximately equal numbers of Parity 1-2 sows and Parity 3-6 sows. Less than 50% of all penmates within the respective groups were familiar, having shared a pen during the previous gestation.

The five treatment groups included:

  • Control: Group of sows formed as above;

  • Familiar: Sows from the same previous gestation group;

  • Dominant: Standard group of sows and three socially dominant animals that were large (Parity 5 or higher), housed together for at least six weeks, and well acquainted with the mixing pen;

  • Protected: Standard group of sows, but provided with seven free-access half-stalls to offer protection to head and shoulders; and

  • Exposed: Standard group of sows, except these sows were weaned directly into the mixing pen and held there for 48 hours before being moved to the breeding stall.

After regrouping, saliva samples and data on aggression and injuries were collected.

Scores for aggression and injuries among the five social management treatments are detailed in Table 1. The “familiar” treatment, where group integrity is maintained, appears to provide the best opportunity for reducing aggression. Researchers believe that the relatively short fights that occurred among familiar sows probably represented reinforcement of social position rather than the establishment of new hierarchy.

In the “dominant” group, the presence of three older animals from a well-established social order produced fewer aggressive events, particularly on the first day of group formation. The concept behind this treatment is that sows would avoid aggression when in the presence of a clearly dominant individual.

The “exposed” treatment, where sows had spent 48 hours together after weaning, but before being placed in stalls for breeding, did not reduce the incidence of aggression compared to the “control” group, except on the first day. But the level of injuries was reduced.

Researchers noted the short period of pre-exposure used in this study may have only provided a weak social order that required additional establishment after the subsequent regrouping.

This study confirmed other reports showing the ineffectiveness of protective stalling on the aggression among regrouped sows, as in the “protected” group.

No differences were observed in overall salivary cortisol concentrations — a measure of stress levels — among the five treatment groups (Table 1).

However, there were differences in cortisol levels on different days, with the lowest concentration prior to regrouping, and the highest levels on all the days following regrouping (Table 2).

In conclusion, maintaining sows in similar groups from gestation period to gestation period increases the odds of reduced aggression, compared to the other regrouping strategies tested.

But this method would not always be practical. Having dominant sows within the group tended to reduce aggression and injuries on the first day following regrouping. A similar trend was found when sows were exposed to each other before breeding. Protection during regrouping didn't prevent aggression or injuries.

Researchers: H.W. Gonyou and S.M. Hayne, both of the Prairie Swine Centre (PSC). Contact Ken Engele of the PSC by phone (306) 373-9922, fax (306) 955-2510 or e-mail [email protected].

Table 1. Incidence of Aggression and Injuries Among Regrouped Sows on Five Social Management Treatments

  Treatments
Control Dominant Exposed Protected Familiar
Fighting (#/6 hrs)
Overall 6.4 4.3 6.9 13.9 5.7
1st day 11.4 5.8 8.6 17.5 10.8
2nd day 3.9 3.7 6.3 6.5 2.9
3rd day 3.7 3.9 5.8 17.7 3.5
Fighting (sec/6 hrs)
Overall 79 48 71 105 21
1st day 203 88 116 207 45
2nd day 17 37 63 55 11
3rd day 18 28 32 54 8
Injuries (score)1
Day 1-3 7.7 6.2 4.7 6.2 4.2
10 days 4.1 5.6 3.3 3.3 2.5
Cortisol (nmol/L)2
Overall 5.9 7.2 5.6 4.0 5.8
1Twelve regions of the body were scored as either 0 = no injury; 1 = slight injury (<5 superficial wounds); 2 = obvious injury (5-10 superficial wounds and/or < = 3 deep wounds); 3 = severe injury (>10 superficial wounds and/or >3 deep wounds). The total score was used in the analysis.
2Cortisol (nmol/L) nanomoles/litre: represents the concentration of cortisol (stress hormone) in saliva.

Table 2. Incidence of Aggression and Injuries Among Regrouped Sows on Five Social Management Treatments

  Day
  Pre 24 hr. 48 hr. 72 hr. 10 days
Cortisol (nmol/L)1 3.9 5.9 6.6 5.6 6.5
1Nanomoles/liter represents the concentrations of cortisol (stress hormone) in saliva.

Transport Space Allowances Studied for Weaned Pigs

Because the optimum space allowance required for weaned pigs during transport is unknown, Texas Tech University scientists sought to establish a first estimate of their space requirements based on measures of animal well-being.

A commercial livestock trailer was divided into compartments fitted for 100, 11.5-to-22-lb., weaned pigs at a space allowance of 0.5, 0.6 and 0.7 sq. ft./pig. Instruments recorded environmental conditions. Digital scans recorded the frequency of standing or lying behaviors of pigs every minute during the trip.

Prior to transport, blood samples were taken from four pigs per compartment for physiology and immune measures, and weight and lesion scores were recorded.

Pigs were then transported two hours to the wean-to-finish site using the same route for each of the four replications during winter.

At the finishing site, blood samples were again taken from the same experimental pigs.

Space allowance influenced the behavior of weaned pigs in the last 15 minutes of transport (Figure 1). Pigs transported at 0.6 sq. ft./pig spent less time standing than pigs transported at 0.5 and 0.7 sq. ft./pig.

Reduced standing behavior in pigs transported at 0.6 sq. ft./pig suggests that these pigs may have been in a more “relaxed” state during the last 15 minutes of transport, or became habituated to transport conditions sooner than pigs transported at 0.5 or 0.7 sq. ft./pig.

Researchers contend pigs appear to spend the majority of their time during transport active. However, pigs transported at 0.6 sq. ft./pig appear to spend more of their time resting than the other two treatment groups.

Cortisol concentrations and the neutrophil-to-lymphocyte ratio both increased during transport regardless of space allowance, trailer deck or gender (Table 1).

Increased cortisol concentrations and neutrophil-to-lymphocyte ratio in transported weaned pigs suggests these pigs experience stress, but the stress was not impacted by the space allowances tested.

Albumin concentrations were increased after transport, suggesting that these pigs were slightly dehydrated. Increased concentrations of create kinase and aspartate aminotransferase after transport suggest that these pigs were somewhat fatigued as a result of the two-hour transport. However, there was no effect of space allowance on any of these measures (Table 1).

No pigs died or were injured during the transport study. Body weight loss during transport did not differ among space allowances tested.

Researchers: M.A. Sutherland, N. Krebs, J.S. Smith and J.J. McGlone, all of the Pork Industry Institute, Texas Tech University. Contact Sutherland by phone (806) 742-2805 (ext. 253), fax (806) 742-4003 or e-mail [email protected].

Table 1. Blood Chemistry and Cortisol Concentrations of Weaned Pigs Before and After a Two-Hour Transport

  Time
  Before Transport After Transport
Number of animals 48 48
Neutrophil-to- Lymphocyte ratio 0.3 1.28
Cortisol, ng/mL1 40.7 62.7
Glucose, mg/dL2 128.5 125.0
Blood urea nitrogen, mg/dL3 8.5 9.8
Albumin, g/dL3 3.5 3.8
Aspartate aminotransferase, IU/L4 45.9 63.4
Creatine kinase, IU/L4 724.3 1,457.3
1Ng/mL = nanograms per milliliter
2Mg/dL = milligrams per deciliter
3g/dL = grams per deciliter
4IU/L = international units per liter

Alternate Tail Docking Procedure Cuts Stress

The use of the cautery iron rather than the conventional blunt trauma cutting method of tail docking can reduce the elevated stress response seen in newborn piglets without the use of analgesics or anesthetics.

Tail docking is routinely performed on piglets to prevent tail biting behavior.

Because analgesics and anesthetics are not routinely used to relieve the pain associated with tail docking on commercial hog farms, research was conducted to compare the stress response to tail docking using two methods: cautery iron (CAUT) and the more commonly used blunt trauma cutters (BT).

Six-day-old piglets' tails were docked using CAUT, BT or sham tail docked, where pigs were handled as if docking tails, but leaving their tails intact (CON). Blood samples were taken prior to tail docking and at 30, 60 and 90 minutes after tail docking to evaluate the effect of the procedure on cortisol concentrations, commonly used to assess stress levels (Figure 1, page 24). Piglet behavior was also recorded in the farrowing crate using one-minute scan samples via live observations for 60 minutes prior to and 90 minutes after tail docking.

Sixty minutes after tail docking, pigs tail docked using CAUT and CON had similar cortisol levels. Therefore, tail docking using cautery may reduce the acute stress response to tail docking.

Piglets tail docked using CAUT and BT spent more time posterior-scooting compared with CON piglets between 0 and 15 and 31 and 45 minutes after tail docking (Fiqure 2).

Elevated blood cortisol can be reduced with cautery iron rather than the BT method of tail docking. Although the tail docking-induced rise in cortisol was prevented by using CAUT, the behavioral responses to BT and CAUT docking methods were similar.

Researchers: M.A. Sutherland, P.J. Bryer, N. Krebs and J.J. McGlone, all of Texas Tech University. Contact Sutherland by phone (806) 742-2805 (ext. 253), fax (806) 742-4003 or e-mail [email protected].

Waterer Bowl Location In Nursery Pens Tested

Pigs' preference for the location of drinker bowls was tested in a commercial nursery barn near Jefferson City, MO. Twenty-five, 7-week-old crossbred gilts were allocated to one of nine pens, configured with three treatment options:

Treatment 1 had one water bowl located on the same side of the pen as the feeder, close to the back wall (F).

Treatment 2 pens were equipped with two water bowl drinkers. One bowl was positioned as F (above), and the second was located across from the feeder along the back wall (O).

Treatment 3 had three water bowl drinkers/pen. Two were positioned as F and O, and the third bowl was located across from the feeder, but next to the alleyway (A).

Pigs preferred the drinker along the back wall (O), when given three choices (Figure 1). But when offered two water bowl drinker locations, they did not show a preference (F vs. O).

The least preferred location for a water bowl was next to the alleyway (A).

The number and length of aggressive interactions around the water bowl drinkers did not differ among treatment groups (Figure 2).

Researchers: C.J. Jackson, A.K. Johnson, L.J. Sadler, K.J. Stalder and L.A. Karriker, DVM, Iowa State University; R.E. Edler and J.T. Holck, Boehringer Ingelheim Vetmedica, Inc.; and P.R. DuBois, DVM, Cargill Pork. Contact Johnson by phone (515) 294-2098, fax (515) 294-4471 or e-mail [email protected].

Nutrition

Study Tracks Feeder Settings' Impact on Growth Performance

Feed intake and daily gain increased as feeder openings increased, but feed efficiency improved the most at the middle feeder adjustment setting in recent Kansas State University (KSU) grow-finish studies.

KSU researchers set out to determine the effect of different feeder settings on growth performance and whether diet type influenced the optimal feeder setting. Two experiments were conducted in a double curtain-sided, deep-pit commercial swine facility with a totally slotted floor.

Each pen was equipped with a stainless steel Staco dry self-feeder and one cup waterer. Each five-hole, single-sided feeder had a feed pan dimension of 60 in. long × 7 in. wide × 5.75 in. high.

The feeder settings were based on the factory-cut holes in the side of the feeder. Moving a dial from one hole to the next adjusted the feeder gate. Feeder setting 1 was the most open setting, while setting 5 was the most closed feeder setting.

Researchers measured feeder gap openings so the data collected could be applied to other types/brands of dry feeders. The distance between the feeder trough and the top of the feed plate was measured on both the left and right sides of the feeder in both trials. The width of the feed plate was subtracted from the height measurement to determine gap opening.

The feed gate was designed to have some “give” or “play” to allow for feed agitation. Thus, the gap opening had a low and high position, which was measured when the feed plate was in the lowest and highest positions possible.

Gap opening measurements on the left and right sides of the feeder were obtained and averaged for each respective position, low or high, for each feeder. The high gap opening measurements and percentage of pan coverage were plotted and the resulting graph was used to develop a regression equation. This regression equation makes it possible to estimate the pan coverage at any feeder gap opening.

The first experiment, a 70-day study, took place in the late spring and early summer of 2007. A total of 1,170 barrows and gilts were randomly assigned among five treatments, with nine replications per treatment. Each pen contained 23-28 pigs with an equal distribution of barrows and gilts.

Pigs were fed a corn-soybean meal-based experimental diet in meal form. The feeder settings were set at 1, 2, 3, 4 or 5 for the five experimental treatments. Feeders were left at their respective settings for the duration of the trial.

Pigs and feeders were weighed on the first day of the experiment (Day 0), and on Days 14, 28, 50 and 70 to determine average daily gain (ADG), average daily feed intake (ADFI), and feed-to-gain ratio (F/G). The two heaviest pigs from all pens were visually selected and marketed on Day 50. The remaining pigs were marketed on Day 70.

Researchers took a digital photo of each feed pan during Weeks 2, 4, 7 and 10 (See Figures 1, 2 and 3 ). Photos were analyzed separately by a trained panel of six people. Each picture was scored according to the percentage of the feed pan that was covered with feed.

From Day 0 to 28, pigs fed from feeders with increasing feeder openings had increased ADG and ADFI (Table 1, page 26).

The feeder setting did not seem to impact growth performance traits from Days 28 to 70. For the test period (Day 0 to 70), as feeder openings increased, ADFI increased. Changing feeder setting did not affect ADG or F/G. Gap opening and pan coverage data for the first experiment are shown in Tables 2 and 3.

In a second experiment, 1,250 barrows and gilts were studied for a 69-day period. Pigs were randomly assigned to one of six treatment groups, with eight replications per treatment. Each pen held 27-28 pigs with an equal distribution of barrows and gilts.

The study focused on the main effects of diet composition on the Staco stainless steel dry feeder at settings 1, 3, and 5. A basic corn-soybean meal diet with a by-product-based diet containing 15% DDGS and 5% bakery by-product was fed. The feeders remained at their respective setting for the duration of the trial.

Pigs and feeders were weighed on the first day of the experiment, then again on Days 15, 30, 42, 55 and 69 to determine ADG, ADFI and F/G.

Photos were taken of each feed pan during Weeks 2 and 6 and pictures were individually scored for pan coverage. Gap openings were measured according to the same procedures used in the first experiment.

From Day 0-30 and Day 30-69, pigs fed from feeders with increasing feeder openings had increased ADG and ADFI (Table 4, page 27). Overall, there were no interactions between feeder setting and diet type for growth performance in Experiment 2. Diet type did not affect growth performance (Table 5).

As feeder openings increased, ADG and ADFI increased. Pigs on feeder setting 1 grew fastest. When the setting was increased from 3 to 5 (the most closed setting), there was a large decrease in ADG. Optimal F/G occurred when feeders were on setting 3.

As the feeder setting increased, low gap opening and high gap opening decreased (Table 6). As feeder setting increased (decreasing gap opening), the percentage of the feeder pan covered with feed decreased for Weeks 2 and 6 (Table 7). Feed pan coverage at each gap opening was similar to coverage in the first experiment. Approximately 50% of the feed pan was covered with the high gap opening of 1.15 in. (Figures 1 and 2).

KSU researchers concluded that feeder setting 3 was optimal. The average gap opening at that setting — from the feed trough to the bottom of the feed plate — was approximately 1.15 in. when the feed plate was in the high position. The amount of feed covering the bottom surface of the feeder pan averaged 61% at setting 3. However, the range for individual feeders on setting 3 was large — ranging from 14 to 93%.

On the basis of this data, KSU researchers recommend feeders be adjusted to allow feed to cover slightly more than half of the feed pan without feed accumulating in the corners.

Researchers: Alan Duttlinger; Steve Dritz, DVM; Mike Tokach; Joel DeRouchey; Jim Nelssen; and Robert Goodband, Kansas State University. Contact Duttlinger at (785) 532-1270, or email [email protected].

Table 1. Influence of Feeder Adjustment on Growing-Finishing Pig Performance (Experiment 1)1

Item Feeder Setting
1 2 3 4 5
Day 0 to 28
Initial wt., lb. 129.0 129.2 128.4 128.7 129.7
Avg. daily gain, lb. 1.85 1.84 1.80 1.80 1.78
Avg. daily feed intake, lb. 4.51 4.46 4.32 4.30 4.30
Feed:Gain 2.45 2.43 2.41 2.39 2.42
Day 28 to 70
Avg. daily gain, lb. 1.72 1.78 1.81 1.73 1.74
Avg. daily feed intake, lb. 4.85 4.93 4.88 4.73 4.76
Feed:Gain 2.81 2.78 2.69 2.75 2.73
Day 0 to 70
Avg. daily gain, lb. 1.77 1.80 1.81 1.76 1.75
Avg. daily feed intake, lb. 4.71 4.74 4.65 4.55 4.56
Feed:Gain 2.65 2.63 2.57 2.59 2.60
Final weight, lb. 251.6 253.7 256.5 251.6 252.5
1A total of 1,170 pigs (PIC initially 129 lb.) were used in a 70-day experiment with 23 to 28 pigs per pen and nine pens per treatment.

Table 2. Influence of Feeder Adjustment on Feeder Gap Opening (Exp.1)1

Gap Opening, in.2 Feeder Setting
1 2 3 4 5
Low 1.14 1.04 0.90 0.79 0.68
High 1.42 1.30 1.16 1.05 0.87
1A total of 1,170 pigs (PIC initially 129 lb.) were used in a 70-day experiment with 23 to 28 pigs per pen and nine pens per treatment.
2Measured from the bottom of the feed pan to the bottom of the feed plate with the feed plate at the lowest (low) and highest (high) possible positions.

Table 3. Influence of Feeder Adjustment on Feeder Pan Coverage (Exp. 1)1

Pan Coverage, % Feeder Setting
1 2 3 4 5
Week 2 74.0 71.3 57.0 34.3 20.6
Week 4 73.1 65.9 62.9 41.9 24.9
Week 7 78.0 67.0 63.7 46.3 24.8
Week 10 78.9 73.9 64.6 45.2 26.1
1A total of 1,170 pigs (PIC initially 129 lb.) were used in a 70-day experiment with 23 to 28 pigs per pen and nine pens per treatment.

Table 4. Influence of Feeder Adjustment and Diet Type on Growing-Finishing Pig Performance (Experiment 2)1

Item Corn-soybean Meal By-product
Feeder Setting Feeder Setting
1 3 5 1 3 5 Diet × Feeder Setting Diet Feeder Setting
Day 0 to 30
Initial wt., lb. 77.4 77.5 77.2 77.2 77.5 77.1 1.00 0.97 0.99
Avg. daily gain, lb. 2.09 2.04 1.91 2.01 2.04 1.97 0.22 0.92 0.01
Avg. daily feed intake, lb. 4.35 4.16 4.03 4.36 4.29 4.05 0.68 0.42 0.01
Feed:Gain 2.07 2.06 2.14 2.19 2.09 2.06 0.13 0.63 0.46
Day 30 to 69
Avg. daily gain, lb. 2.11 2.06 1.94 2.09 2.07 1.94 0.90 0.97 0.01
Avg. daily feed intake, lb. 5.49 5.25 5.03 5.43 5.26 5.04 0.86 0.81 0.01
Feed:Gain 2.60 2.55 2.60 2.60 2.55 2.60 1.00 0.88 0.26
Day 0 to 69
Avg. daily gain, lb. 2.10 2.05 1.92 2.06 2.05 1.95 0.37 0.87 0.01
Avg. daily feed intake, lb. 4.99 4.77 4.59 4.95 4.84 4.61 0.74 0.75 0.01
Feed:Gain 2.37 2.34 2.40 2.42 2.34 2.35 0.31 0.87 0.19
Final weight, lb. 223.5 220.6 212.1 221.4 220.3 214.2 0.81 0.97 0.02
1A total of 1,250 pigs (PIC initially 77.3 lb.) were used in a 69-day experiment with 27 to 28 pigs per pen and eight pens per treatment for the treatments of feeder setting 1 and 3 for both diet types, and seven pens per treatment for the treatments of feeder setting 5 for both diet types.

Table 5. Main Effects of Feeder Adjustment on Growing-Finishing Pig Performance (Exp. 2)1

Item Feeder Setting
1 3 5
Day 0 to 30
Initial wt., lb. 77.3 77.5 77.1
Avg. daily gain, lb. 2.05 2.04 1.94
Avg. daily feed intake, lb. 4.35 4.22 4.04
Feed:Gain 2.13 2.07 2.10
Day 30 to 69
Avg. daily gain, lb. 2.10 2.06 1.94
Avg. daily feed intake, lb. 5.46 5.26 5.03
Feed:Gain 2.60 2.55 2.60
Day 0 to 69
Avg. daily gain, lb. 2.08 2.05 1.94
Avg. daily feed intake, lb. 4.97 4.80 4.60
Feed:Gain 2.39 2.34 2.38
Final weight, lb. 222.5 220.4 213.2
1A total of 1,250 pigs (PIC initially 77.3 lb.) were used in a 69-day experiment with 27 to 28 pigs per pen and eight pens per treatment for the treatments of feeder setting 1 and 3 for both diet types, and seven pens per treatment for the treatments of feeder setting 5 for both diet types.

Table 6. Influence of Feeder Adjustment on Gap Opening (Experiment 2)1

Gap Opening, in.2 Feeder Setting
1 3 5
Low 1.13 0.86 0.62
High 1.42 1.14 0.87
1A total of 1,250 pigs (PIC initially 77.3 lb.) were used in a 69-day experiment with 27 to 28 pigs per pen and eight pens per treatment for the treatments of feeder setting 1 and 3 for both diet types, and seven pens per treatment for the treatments of feeder setting 5 for both diet types.
2Measured from the bottom of the feed pan to the bottom of the feed plate with the feed plate at the lowest (low) and highest (high) possible positions.

Table 7. Influence of Feeder Adjustment and Diet Type on Feeder Pan Coverage (Exp. 2)1

Feeder Pan Coverage, % Corn-soybean Meal By-product
Feeder Setting Feeder Setting
1 3 5 1 3 5 Diet × Feeder Setting Diet Feeder Setting
Week 2 73.3 46.9 19.4 85.5 63.2 17.8 0.37 0.10 0.01
Week 6 74.7 53.3 25.9 85.3 70.3 22.4 0.17 0.10 0.01
1A total of 1,250 pigs (PIC initially 77.3 lb.) were used in a 69-day experiment with 27 to 28 pigs per pen and eight pens per treatment for the treatments of feeder setting 1 and 3 for both diet types, and seven pens per treatment for the treatments of feeder setting 5 for both diet types.

Feeder Design Impacts Growth Performance, Carcass Traits

Wet-dry feeders improved finishing pigs' feed intake by close to 9% and growth rate by 6-7% compared to conventional dry feeders in two recent Kansas State University research trials. And, pigs fed on wet-dry feeders were 4.5% heavier at marketing, but their carcasses were fatter and they yielded less than the pigs fed with conventional feeders.

Both experiments investigated the effects of conventional dry feeders with cup waterers (see Figure 1), compared to wet-dry feeders with a nipple in the feed pan, their sole source of water. Although pens with a wet-dry feeder also contained a cup waterer, they were shut off during the experiments.

Water was delivered to all of the pens of each feeder type, independently, and daily water consumption was measured using water meters.

The first experiment included 1,186 pigs, averaging 70.8 lb., on test. Groups were divided into 26-28 pigs/pen and allocated to one of two feeder types (22 pens/feeder type).

All pigs received the same diet sequence in four phases — Day 0-10, Day 10-28, Day 28-50 and Day 50-69.

Overall, pigs using the wet-dry feeder had greater average daily gain (ADG), average daily feed intake (ADFI) and final weight compared with pigs using the conventional dry feeder (Table 1). Feed-to-gain ratio (F:G) was essentially the same with both feeder types.

Average daily water usage for pigs on the wet-dry feeder was 1.44 gal./day. Pigs on the conventional dry feeders averaged 1.38 gal./day.

The second experiment was conducted with 1,236 pigs allotted to pens with one of the two feeder types. There were 23 pens per feeder type with 25-28 pigs/pen. Pig weights averaged 63.2 lb. at the beginning of the 104-day research trial. All pigs were fed the same feed budget.

The three largest pigs per pen were marketed on Day 84. The remaining pigs were fed a fifth dietary phase containing Paylean until they were slaughtered on Day 104. Table 3 shows the effects of feeder design on the carcass characteristics and the resulting economic return.

Overall, pigs using the wet-dry feeder had greater ADG, ADFI and final weight compared with those using the conventional dry feeder. However, pigs using the wet-dry feeder consumed more feed, had poorer feed/gain and higher feed cost/pig than pigs using the conventional feeder (Table 2).

Carcass yield, fat-free-lean index, premium per pig and live value per cwt. were higher and average backfat depth was lower for pigs using the conventional dry feeder. All of these effects combined resulted in a lower net income per pig for pigs fed with the wet-dry feeder (Table 3).

The KSU researchers felt the experiments demonstrated that growth performance is improved when pigs are offered feed and water, ad libitum, via a wet-dry feeder when compared to a conventional dry feeder and drinker bowl.

Still, the research results brought up some interesting questions for further study, such as: “Can we manage within-group variation better by feeding the lightest pigs placed in a finisher, or even gilts, with a wet-dry feeder?” asks Jon Bergstrom, KSU swine laboratory research coordinator.

He predicts that with the growing emphasis on understanding behavior, maximizing welfare and related productivity, research in this area will continue. And he wonders if feeder design and feed presentation can overcome the reduced feed intake associated with feeding some by-products.

Because carcasses of pigs fed with a wet-dry feeder yielded less and were fatter, the use of wet-dry feeders may not be justified with some carcass incentive programs, note researchers.

Researchers: Jon Bergstrom; Mike Tokach; Steve Dritz; Jim Nelssen, DVM; Joel DeRouchey and Robert Goodband, Kansas State University. Contact Bergstrom at 785-532-1277 or e-mail [email protected].

Table 1. The Effects of Feeder Design on Growth Performance of Finishing Pigs (Experiment 1)1

Item Feeder Type
Conventional Dry Wet-Dry
Day 0 to 69
Avg. daily gain, lb. 2.10 2.26
Avg. daily feed intake, lb. 5.13 5.58
Feed:Gain 2.44 2.47
Day 69 average wt, lb. 216.35 227.30
Water use, gal./day per pig 1.38 1.44
Water use, gal./lb. gain 0.66 0.64
1A total of 1,186 pigs (PIC, 337 × 1050) with 26 to 28 pigs per pen and 22 pens per treatment were used in a 69-day experiment to compare the growth performance of pigs fed from either a conventional dry feeder with a cup waterer or a wet-dry feeder.

Table 2. The Effects of Feeder Design on Growth Performance of Finishing Pigs (Experiment 2)1

Item Feeder Type
Conventional Dry Wet-Dry
Day 0 to 104
Avg. daily gain, lb. 1.90 2.01
Avg. daily feed intake, lb. 4.96 5.40
Feed:Gain 2.62 2.68
Day 104 average wt, lb. 261.35 272.80
Water use, gal./day per pig 1.68 1.48
Water use, gal./lb. gain 0.89 0.73
1A total of 1,236 pigs (PIC, 337 × 1050) with 25 to 28 pigs per pen and 23 pens per treatment were used in a 104-day experiment to compare the growth performance of pigs fed from either a conventional dry feeder with a cup waterer or a wet-dry feeder.

Table 3. The Effects of Feeder Design on the Carcass Characteristics of Finishing Pigs and Economic Return (Example 2)1

Item Feeder Type
Conventional Dry Wet-Dry
Plant live wt, lb. 253.7 265.9
Hot carcass weight, lb. 194.9 200.0
Yield, % 76.86 75.21
Avg. backfat depth, in. 0.64 0.70
Loin muscle depth, in. 2.41 2.45
Lean, % 57.10 55.89
Fat-free lean index 50.48 49.94
Premium/pig, $ 8.67 5.26
Value/hundred weight (live), $ 56.28 54.83
Total revenue/pig, $2 142.78 145.80
Feed cost/pig, $ 56.23 61.12
Feed, $/cwt. gain 28.43 29.17
Net income/pig, $ 26.15 24.28
1Carcass data from 494 pigs (11 pens/feeder-type) were obtained for the comparison of carcass data and economic evaluation.
2Base carcass price of $71.43/cwt. as used to calculate total revenue. Facility cost of $10.40/pig and initial pig cost of $50.00/pig were used to calculate net income per pig.

Corn and DDGS Diet Switching Do Not Affect Pig Performance

Pork producers looking to optimize feed ingredients are including distiller's dried grains with solubles (DDGS) for grow-finish pigs when costs are in line.

To better understand the implications of suddenly including economically priced DDGS in pig diets, researchers at the University of Minnesota conducted a trial to determine the effects of switching between corn-soybean meal and corn-soybean meal-DDGS diets on pig performance and carcass quality of finishing pigs.

The 216 pigs housed in 24 pens were placed on one of four dietary treatments — the corn-soybean control diet (D0), a corn-soybean meal diet containing 20% DDGS fed throughout the study (D20), D20 and D0 diets alternated bi-weekly (D20SW), and a 40% DDGS diet alternated bi-weekly with the D0 diet (D40SW). Pigs were fed corn-soybean meal diets until they went on test at 110 lb.

There were five, two-week feeding periods. Pigs assigned to the D20SW and D40SW treatments started and ended the trial on DDGS-containing diets.

Dietary treatments had no effect on average daily gain (Table 1). Except for feed efficiency, growth performance was similar for pigs fed the control diet continuously, the 20% DDGS diet continuously or the 20% DDGS and control diets in an alternating pattern.

Researchers point out that for some reason, pigs fed the 20% DDGS diet were continuously less efficient than pigs fed the DDGS diet alternated with the control diet.

They also noted that the pigs switched on and off a 40% DDGS diet were lighter at the end of the 70-day study (Table 1), and these pigs yielded lighter carcasses than pigs in other treatment groups because they ate less feed.

Dressing percentage and carcass fat-free lean percentage were not affected by dietary treatments.

The results of this study showed no adverse effects of frequently alternating between inclusion and removal of 20% DDGS from diets for finishing pigs in terms of performance or carcass characteristics.

The researchers plan to conduct a related trial to determine if lighter pigs will respond in the same manner.

Researchers: Lee Johnston and Adrienne Hilbrands, University of Minnesota, West Central Research and Outreach Center; and Jerry Shurson, University of Minnesota-St. Paul. Contact Johnston by phone (320) 589-1711, fax (320) 589-4870 or e-mail [email protected].

Table 1. Effects of Frequent DDGS Inclusion and Removal on Pig Performance and Carcass Traits

Trait D01 D202 D20SW3 D40SW4
Initial weight, lb. 113.0 113.0 113.0 113.3
Final weight, lb. 247.4xy 247.4xy 249.1x 243.8y
Average daily gain, lb. 1.92 1.92 1.94 1.87
Average daily feed intake, lb. 5.95xy 6.06x 5.97xy 5.80y
Feed:Gain 3.09ab 3.15a 3.08b 3.10ab
Hot carcass weight, lb. 184.7a 184.3a 185.8a 178.8b
Dressing, % 74.8 74.6 74.6 73.8
Carcass lean, % 54.4 54.0 53.8 54.2
abWithin a row means without a common superscript differ (P < 0.05).
xyWithin a row means without a common superscript differ (P < 0.10).
1Corn-soybean meal control
2Corn-soybean meal diet containing 20% DDGS fed throughout the study
3D20 and D0 diets alternated bi-weekly
440% DDGS diet alternated bi-weekly with the DO diet

Enhanced DDGS Offer Improved Swine Diets

Enhanced distiller's dried grains with solubles (E-DDGS) provides greater energy concentration in swine diets, improving the nutritional value of DDGS for pigs, according to a study at the University of Illinois.

The end result is not only improved feed efficiency, but in many cases, increased growth rates, leading to increased profits.

DDGS has a high fiber content. A process known to separate fiber from DDGS — called the elusieve process — removes about 10% of the material, mostly fiber, yielding E-DDGS with 2.3% less total dietary fiber than conventional DDGS (28.7% vs. 26.4% fiber).

The E-DDGS has higher crude protein (CP) and higher fat concentration (Table 1).

The goal of this experiment was to determine digestible energy (DE) and metabolizable energy (ME) in two sources of DDGS, and in E-DDGS produced from each of the DDGS sources.

The trial consisted of 30, 51-lb. growing pigs and 30, 161-lb. finishing pigs placed in metabolism cages and assigned a randomized diet.

The two groups of pigs received five different diets: standard corn and soybean meal and four additional diets formulated by replacing 40% of the base diet with 40% of each source of DDGS and E-DDGS.

Pigs were fed experimental diets for 14 days. Urine and feces were collected during the final five days.

Diets containing E-DDGS produced 6-7% greater DE and ME than those containing DDGS (Table 2). Researchers said the result was expected due to the fiber removal from DDGS, resulting in an ingredient higher in fat and protein content.

About 94% of the DE and ME in the original DDGS was captured in the E-DDGS. The DE and ME values were not different between growing and finishing pigs.

In conclusion, the co-product E-DDGS is nutritionally more appropriate for pigs than DDGS because of the lower fiber concentration and higher energy density.

Researchers: J.A. Soares, H.H. Stein, R. Srinivasan, V. Singh and J.E. Pettigrew, University of Illinois. Contact Pettigrew by phone (217) 244-6927, fax (217) 333-7861 or e-mail [email protected].

Table 1. Nutrient Composition As Fed, (%)

Item DDGS-11 DDGS-2 E-DDGS-12 E-DDGS-2
Dry Matter, % 90.16 88.77 91.62 90.16
Crude Protein, % 28.14 26.74 30.01 28.20
Ether Extract, % 9.94 10.85 10.36 11.27
Total Dietary Fiber, % 29.61 27.79 25.10 25.34
1DDGS refers to distiller's dried grains with solubles.
2E-DDGS refers to enhanced distiller's dried grains with solubles.

Table 2. Energy Values of DDGS1 and E-DDGS2

Item Ingredient
DDGS-1 DDGS-2 E-DDGS-1 E-DDGS-2
Growing pigs
Digestible energy, kcal/kg, dry matter 3,390 3,483 3,703 3,670
Metabolizable energy, kcal/kg, dry matter 3,047 3,159 3,226 3,339
Finishing pigs
Digestible energy, kcal/kg, dry matter 3,303 3,436 3,518 3,691
Metabolizable energy, kcal/kg, dry matter 3,128 3,239 3,293 3,453
1DDGS refers to distiller's dried grains with solubles.
2E-DDGS refers to enhanced distiller's dried grains with solubles.

Feed Additives Don't Resolve Mycotoxin Contamination

Two related feed additives failed to resolve the impact of mycotoxin contamination in a nursery pig trial.

Feeding diets containing about 2 ppm Deoxynivalenol (DON), a mycotoxin, depressed feed intake by almost 10% when consumed by nursery pigs for three weeks.

Moreover, feed additives, regardless of their mode of action, did not reverse the detrimental effects of the mycotoxin.

DON is a mycotoxin produced by fusarium molds found in corn and wheat. Pigs consuming DON-contaminated feed will initially reduce the amount of feed consumed as well as growth rate. Signs such as vomiting are evident if the contamination is severe. This can have serious consequences resulting in an economic loss of 8-10 ($CAN)/hog (under average market conditions).

Several feed additives are reported to reduce the effect of the mycotoxin by either binding the mycotoxin in the gut and preventing absorption, chemically transforming the toxin to decrease its toxicity or enhancing immune system function.

To test the additives, five nurseries with 24 pens/nursery and four pigs/pen weighing 20 lb. were fed 0.6 lb. of Provision 1, then Provision 2 (FeedRite, Winnipeg, Canada) until Day 14, and treatment diets containing DON from Day 15-35, postweaning.

Pigs were weighed seven and 14 days postweaning, and at the start and end of treatment diets at 35 days of age when they exited the nursery.

Treatment diets were formulated to meet or exceed nutrient requirements for pigs of this age. Samples of corn shown to contain DON were used for 35% of the corn in nursery diets to provide an average of 2 ppm DON in the nursery diets.

Diet samples showed control diets were negative for DON, compared to up to 2.61 ppm DON in late nursery diets.

Overall, average daily gain and average daily feed intake of control pigs were superior to pigs consuming a diet containing DON, regardless of the feed additive used.

Researchers: A.D. Beaulieu, J.F. Patience and D. Gillis, all of the Prairie Swine Center at Saskatchewan, Canada. Contact PSC's Ken Engele by phone (306) 373-9922, fax (306) 955-2510 or e-mail [email protected].

Adding Amino Acids Cuts Protein Costs, Boosts Net Energy

Supplementing a low-protein diet with synthetic amino acids can provide a cost-effective way to avoid adding excess crude protein (CP).

Two experiments with grow-finish pigs confirmed that performance could be maintained when either high- or low-crude protein diets are fed as long as amino acids are balanced and the diets are formulated to provide similar net energy.

The introduction of crystalline amino acids has allowed a reduction in the crude protein (CP) in swine diets. Low-CP diets supplemented with essential amino acids can decrease nitrogen excretion in the manure and may reduce diet costs.

This study compared the performance of grow-finish pigs fed either high- or low-CP diets supplemented with crystalline amino acids.

High-CP diets were formulated to meet the lysine and other amino acid requirements of the pig (Table 1). Low-CP diets were formulated to provide the same amount of lysine, but the CP was reduced from 20% to 16% in the grower and from 16% to 12% in the finisher diet.

Diets were formulated to provide equal net energy. Sodium bicarbonate was added to the low-CP diets to maintain the electrolyte balance of the diet.

Average daily feed intake was lower when the pigs consumed the high-CP diet, while average daily gain was similar between treatments, resulting in an improved feed:gain ratio with the high-CP diet (Table 2).

The low- and high-CP diets resulted in similar pig performance during the finishing phase (Table 2).

In summary, CP levels can be decreased by 4% in grower and finisher diets without impacting pig performance, provided that diets are formulated to be equivalent in available amino acid, net energy and dietary electrolyte balance.

Researchers: J.F. Patience, A.D. Beaulieu and I.U. Haq, all of the Prairie Swine Centre (PSC). Contact PSC's Ken Engele by phone (306) 373-9922, fax (306) 955-2501 or e-mail [email protected].

Table 1. Ingredient Composition and Calculated Nutrient Contents of Experimental Diets

Ingredients (% as fed) Grower (55 to 121 lb.) Finisher (165 to 264 lb.)
High crude protein Low crude protein High crude protein Low crude protein
Corn 60.50 73.51 77.25 87.80
Soybean meal 34.50 20.80 18.70 7.40
Tallow 1.13 0.00 0.87 0.00
Lysine 0.00 0.43 0.03 0.38
Methionine 0.00 0.11 0.00 0.02
Tryptophan 0.00 0.05 0.00 0.06
Threonine 0.00 0.05 0.00 0.06
Valine 0.00 0.05 0.00 0.03
Isoleucine 0.00 0.00 0.00 0.03
Othera 3.87 5.69 3.18 4.80
Nutrients
DE, Mcal/kg 3.51 3.41 3.50 3.42
NE, Mcal/kgb 2.30 2.30 2.40 2.40
Crude protein, % 20.44 16.94 16.13 12.31
Calcium, % 0.70 0.70 0.50 0.52
Phosphorous, % (total) 0.60 0.60 0.45 0.47
TID Lys, %c 1.02 1.02 0.66 0.66
TID Met, % 0.29 0.30 0.22 0.26
dEB, meq/kgd 221 222 145 146
aConsisting of dicalcium phosphate, limestone, salt, sodium bicarbonate, potassium carbonate, vitamins,minerals and celite.
bEstimated according to CVB (1998). NE stands for net energy.
cTID refers to true ileal digestible.
dDietary electrolyte balance, milliequivalents/kg.

Table 2. Performance of Grower and Finisher Pigs Fed High- or Low-Crude Protein (CP) Diets

Grower Finisher
High CP Low CP High CP Low CP
Initial body weight, lb. 55.70 55.60 170.00 170.30
Final body weight, lb. 116.14 118.00 255.2 250.40
Avg. daily gain (lb./day) 2.21 2.22 2.44 2.30
Avg. daily feed intake (lb./day) 4.00 4.40 7.60 4.30
Feed:Gain (lb./lb.) 1.21 1.12 1.00 1.00

Supplementing Fall-Back Pigs Pays In the Nursery

A number of Michigan pork producers have questioned whether the “rescue decks” really pay off, according to Barbara Straw, Extension veterinarian at Michigan State University (MSU).

Producers are impressed with the way that disadvantaged pigs perform in the decks in the farrowing house, but question whether those pigs will simply fall back again in the nursery.

Jerry May, MSU Extension swine specialist, set up a trial with a 2,000-sow commercial producer who raised this question.

In the past, it's been common procedure on such an operation to provide supplemental care to pigs that demonstrate slow growth in the first 3-5 days of life.

In this herd studied, routine crossfostering occurs at birth to standardize litter sizes. Then at 3-5 days of age, a litter created from 8-11 undersized pigs is collected from a room of 20 litters. The next gilt to farrow (one of the last in the group to farrow) has all of her piglets removed and transferred to the other remaining newborn litters so she can become a nurse sow for an entirely adopted litter of fallbacks.

In an effort to duplicate the success of using foster litters, an automatic milk feeder was installed to accommodate a litter of healthy piglets. These piglets were moved to the milk feeder to free up their dam to nurse fall-back pigs.

While these foster (fall-back) litters thrived in farrowing, it was unknown whether pigs from these litters would do well in the nursery, or whether they would continue to need special care.

Table 1 depicts the fostering process at the farm for challenged 3-5 day-old pigs. At the same time, 18-day-old pigs were being weaned. The protocol at weaning was to commingle pigs that had received supplemental care in lactation with normal pigs to find out if the supplemented pigs could grow on their own.

In four farrowing rooms at the time of weaning, there were 117 pigs that had been small at 3-5 days of age and placed on foster sows. These pigs were ear tagged to identify them as pigs that had received supplemental care during lactation.

At weaning, 88 of the tagged pigs met the target weight of 13 lb. and were moved to the nursery. Eighteen of the remaining 29 pigs that remained in the farrowing room reached the weaning weight requirement one week later at 25 days of age, while the other 11 pigs died.

To reduce handling stress, weights of tagged and routinely handled pigs were collected one week postweaning, when pigs were vaccinated for Mycoplasmal pneumonia. Pigs were weighed again 35 days postweaning, just prior to movement to the finisher (Table 2).

Overall, three of the undersized pigs died in the nursery (3/106=2.8%), compared to the usual herd nursery mortality of 2.0%. A total of 103 of the undersized pigs completed 35 days in the nursery. And their weight going into the finisher of nearly 40 lb. was no different than normally raised pigs.

In sum, pigs that fail to thrive in the first three days of life are capable of performing adequately if provided supplemental care. These pigs can achieve weights at weaning and at the end of the nursery phase comparable to pigs managed without special care.

Fall-back pigs in this study were due to nutritional deficiencies and not disease, which would have required a different outcome.

Researcher: Barbara Straw, DVM, Michigan State University. Contact Straw by phone (517) 432-5199, fax (517) 432-3450 or e-mail [email protected].

Farm Management Accounting Guide

T. Murphy Associates announces publication of its farm accounting textbook entitled, “Farm Management Accounting in MIS Mode.” The textbook completes the financial software package called agMIS. The 100-plus page illustrated publication explains how to use the agMIS system as intended to support daily management and accounting needs of the farm. The publication delves into the need for greater attention to solving farm software problems. The nine chapters in the text each address a specific management topic, such as managing production costs, managing accrued income, managing cash and taxes, and managing assets and the balance sheet, all with illustrated examples. The book currently exists only in e-book form, and will be distributed free with the agMIS software package at its low price of $225 (plus tax in Nebraska). A printed version is contemplated for use in classrooms. For details, call (402) 433-4801 or visit www.agmis.com.

Send product submissions to Dale Miller, Editor (952) 851-4661; [email protected]

Plastic Flooring Option

Farmweld introduces a new 24 in. × 24 in. plastic panel to complement its Farmweld Flooring System (FFS). With this new size, producers are afforded greater flexibility for designing wider farrowing platform creep areas. FFS panels are molded from high quality, state-of-the-art polypropylene that provides a warm, comfortable surface for baby or nursery pigs to eat and rest. The surface is textured to create excellent traction. The orange, non-porous plastic is easy to clean, promoting rapid transfer of waste into the pit. The FFS has outstanding durability featuring unique stabilizer corners that provide a full inch of vertical beam support. The interlocking design firmly connects for a continuous unit, and positive locking means the panels are as strong at the connection as they are in the center. Fiberglass or galvanized beams are available for the flooring support system. For more information, visit www.farmweld.com or call (800) 328-7675.

Clostridial Diseases Strike Piglets Early

Three types of clostridial organisms commonly affect swine.

There are many causes of diarrhea in newborn piglets. Each organism has a period of time when it is prevalent in the growth stage of a pig. The clostridium family of organisms is no exception.

In swine, we deal primarily with Clostridium perfringens types A and C and Clostridium difficile. Since cross protection doesn't factor in, sorting out which isolate(s) a farm has is very important.

Clostridium perfringens type C has caused diarrhea in newborn piglets for many decades. It is often referred to as “Type C” scours. There is an acute and chronic form. The acute form happens soon after birth. In many cases, mortality can reach 30-70% within 24 hours after birth. There is often a bloody appearance to the diarrhea, and pigs have a classic intestinal lesion identifiable by a postmortem exam. The acute form occurs in piglets born to dams with little or no immunity to Clostridium perfringens type C.

The chronic form of Clostridium perfringens type C usually will occur later in lactation. The signs begin at 10-14 days of age. This diarrhea is not bloody and the classic gut lesion no longer exists.

Clostridium perfringens type A and Clostridium difficile infections have been recognized for 10 years. Both have a common clinical history and in some units occur together. Both organisms cause severe diarrhea in piglets less than 3 days of age. Mortality is normally low, but pigs are stunted, small and uneven at weaning, which can carry into finishing. These pigs are wet, chilled and covered with feces.

Management

Management techniques may actually aid the growth of these organisms. Feedback has been a concern on problem farms. If feedback is too close to farrowing, the sows still shed clostridia into the feces and expose the piglets.

In clostridial cases, we either discontinue feedback or move it back to at least five weeks before farrowing. Broad-spectrum or long-acting antibiotic treatments at birth have also been a concern as the antibiotic may inhibit normal intestinal bacteria from becoming established.

Case Study No. 1

A single-site, 200-sow, farrow-to-finish unit was experiencing diarrhea and high mortality in newborn piglets. The diarrhea was blood-tinged and mortality ranged from 5-60% by 3 days of age.

Postmortem examination of recently deceased piglets revealed classic Clostridium perfringens type C lesions in the small intestine of numerous piglets, confirmed by culture results.

All pigs 0-3 days of age were treated with procaine penicillin because clostridial organisms are very sensitive to penicillin. The farm began to treat all newborn piglets with Clostridium perfringens type C antitoxin. The antitoxin is serum that contains antibodies to clostridium. These antibodies give immediate protection to the piglets, but the protection is short lived.

As per label directions, BMD (Alpharma Animal Health) was added to the lactation ration at 250 g./ton to decrease shedding from the sows. BMD is labeled for type C only. Sows due to farrow were vaccinated with a commercial clostridium perfringens type C vaccine at five and two weeks prefarrow. The immunity from colostrum is long-term immunity.

When piglets were born from these vaccinated sows, we discontinued the use of antitoxin with no adverse effects. Clostridium perfringens type C is so common it is a part of a normal prefarrow vaccination for most units.

Case Study No. 2

A 1,500-sow unit called about diarrhea in newborn piglets. In the previous week, the sow farm saw an explosion of diarrhea in piglets as early as 24 hours after birth. Approximately 40% of litters were affected and gilt litters seemed to be more severe.

Normal treatment protocols for diarrhea were ineffective. Piglets were dirty and wet in a very nice facility with plastic flooring and heat lamps. Preweaning mortality had risen from 9-16%.

Postmortem examinations on numerous piglets showed relatively normal small intestines with fluid-filled large intestines. Culture results showed both Clostridium perfringens type A and Clostridium difficile isolates. These isolates were used to make an autogenous prefarrowing vaccine.

With vaccination, the preweaning mortality returned to normal. The sow farm performed well for about 11 months when similar signs appeared. Another Clostridium perfringens type A was added to the prefarrowing vaccine with good results again.

Clostridial infections in piglets are common. Distinguishing which organism your unit is dealing with is the key to control. Clostridial diseases don't generally lessen with time, so consult your veterinarian for a diagnosis, treatment and prevention protocol for profitable pork production.

Health

Supplementing Fall-Back Pigs Pays In the Nursery

A number of Michigan pork producers have questioned whether the “rescue decks” really pay off, according to Barbara Straw, Extension veterinarian at Michigan State University (MSU).

Producers are impressed with the way that disadvantaged pigs perform in the decks in the farrowing house, but question whether those pigs will simply fall back again in the nursery.

Jerry May, MSU Extension swine specialist, set up a trial with a 2,000-sow commercial producer who raised this question.

In the past, it's been common procedure on such an operation to provide supplemental care to pigs that demonstrate slow growth in the first 3-5 days of life.

In this herd studied, routine crossfostering occurs at birth to standardize litter sizes. Then at 3-5 days of age, a litter created from 8-11 undersized pigs is collected from a room of 20 litters. The next gilt to farrow (one of the last in the group to farrow) has all of her piglets removed and transferred to the other remaining newborn litters so she can become a nurse sow for an entirely adopted litter of fallbacks.

In an effort to duplicate the success of using foster litters, an automatic milk feeder was installed to accommodate a litter of healthy piglets. These piglets were moved to the milk feeder to free up their dam to nurse fall-back pigs.

While these foster (fall-back) litters thrived in farrowing, it was unknown whether pigs from these litters would do well in the nursery, or whether they would continue to need special care.

Table 1 depicts the fostering process at the farm for challenged 3-5 day-old pigs. At the same time, 18-day-old pigs were being weaned. The protocol at weaning was to commingle pigs that had received supplemental care in lactation with normal pigs to find out if the supplemented pigs could grow on their own.

In four farrowing rooms at the time of weaning, there were 117 pigs that had been small at 3-5 days of age and placed on foster sows. These pigs were ear tagged to identify them as pigs that had received supplemental care during lactation.

At weaning, 88 of the tagged pigs met the target weight of 13 lb. and were moved to the nursery. Eighteen of the remaining 29 pigs that remained in the farrowing room reached the weaning weight requirement one week later at 25 days of age, while the other 11 pigs died.

To reduce handling stress, weights of tagged and routinely handled pigs were collected one week postweaning, when pigs were vaccinated for Mycoplasmal pneumonia. Pigs were weighed again 35 days postweaning, just prior to movement to the finisher (Table 2).

Overall, three of the undersized pigs died in the nursery (3/106=2.8%), compared to the usual herd nursery mortality of 2.0%. A total of 103 of the undersized pigs completed 35 days in the nursery. And their weight going into the finisher of nearly 40 lb. was no different than normally raised pigs.

In sum, pigs that fail to thrive in the first three days of life are capable of performing adequately if provided supplemental care. These pigs can achieve weights at weaning and at the end of the nursery phase comparable to pigs managed without special care.

Fall-back pigs in this study were due to nutritional deficiencies and not disease, which would have required a different outcome.

Researcher: Barbara Straw, DVM, Michigan State University. Contact Straw by phone (517) 432-5199, fax (517) 432-3450 or e-mail [email protected].

Table 1. Weight and Numbers of Piglets on Sows in Four Farrowing Rooms Involved in the Milk Deck/Foster Management

Sow ID Original litter that was removed and placed in the auto milk feeder Undersized pigs fostered onto the nurse sow
Number of pigs Average wt. Number of pigs Average wt.
16580 11 3.6 10 1.9
105515 10 2.9 10 1.5
105149 11 3.0 11 1.9
16603 9 2.7 8 2.4
92276 11 2.7 11 1.4
106765 9 2.9 10 1.0
92289 11 2.7 11 1.7
Total 72 2.9 71 1.7

Table 2. Weights (LS means ± SE)

Management Weight 7 days postweaning Weight 35 days postweaning
Foster sow 14.5 (n = 88) 38.6 (n = 1031)
Routinely handled n = 74 14.7 39.4
1Includes late-weaned pigs

Dam Parity Influences Litter Performance, Pig Health

University of Nebraska researchers have confirmed earlier work indicating that sow parity affects the health status of her progeny.

The research team evaluated litter performance and the production and passive transfer of immunoglobulins (Ig) {antibodies} in Parity 1 (P1) dams vs. Parity 4 (P4) dams and their progeny.

Immunoglobulin A (IgA) antibodies protect the mucosal surfaces from infection. Immunoglobulin G (IgG) antibodies provide protection against viruses, bacteria and antitoxins and are found in most tissues and plasma.

Researchers found:

Litter weight tended to be greater for P4 progeny compared to P1 progeny.

Dam parity didn't appear to influence circulating Ig in dams during gestation or at farrowing. But IgA concentrations were generally higher for P4 sows than P1 gilts in samples of colostrum and milk. And serum IgG concentrations were greater for P4 progeny compared to P1 progeny across all preweaning samples.

Dams (Large White × Landrace) were first-parity gilts and fourth-parity sows that farrowed over a 22-day period. Dams were housed in stalls during gestation and moved to farrowing crates about five days prior to their expected farrowing date.

All piglets from each litter were weighed on Day 0, 7, 14 and 19 (weaning).

Blood samples were collected from sows during gestation on Day 90 and 114 and a final time after farrowing.

Samples during lactation were obtained at Day 0 (colostrum), Day 7 (mid-lactation) and Day 14 (late-lactation).

Blood samples were collected from six piglets from each litter on Days 1, 7 and 14.

Dam and litter performance are illustrated in Table 1. Data shows parity had no effect on number of pigs/litter or on litter weaning weights.

But P4 dams tended to have pigs with heavier bodyweights compared to P1 dams, and P4 dams had less preweaning mortality and heavier litter weaning weights.

Figure 1 depicts progeny bodyweights of gilts (P1) and Parity 4 (P4) sows. The P4 progeny had heavier bodyweights among all time points from farrowing to weaning than P1 progeny.

Researchers acknowledged that they expected to observe greater differences in dam and litter performance, but based on previous work, it's possible that the greatest differences in performance occurs between P1 and P2 or P3 dams.

IgG and IgA antibodies in P1 and P4 dams during gestation and after farrowing are represented in Figure 2. While IgA increased as the dams approached farrowing, IgG levels declined over time, with the lowest concentrations observed at farrowing. Researchers suggest this result may contribute to the higher levels of IgA in mid- and late-lactation milk as compared to IgG.

IgG and IgA antibodies in colostrum and milk during lactation are shown in Figure 3. IgG concentrations were unaffected by parity. But IgG antibodies averaged among both parities were greater for colostrum than mid- and late-lactation samples. For IgA, concentrations tended to be greater in P4 dams than P1 dams, and again the greatest concentrations were observed during early lactation (colostrum).

There were no parity-by-time interactions for IgG or IgA antibodies in serum from P1 and P4 progeny (Figure 4). However, among all time points, piglets from P4 dams had greater circulating IgG than P1 dams. Parity had no effect on IgA levels in P1 and P4 progeny, but P1 progeny had lower (numerically) IgA levels compared to P4 progeny at Days 1 and 7.

In conclusion, it appears that mature dams (P3+) may provide their progeny with performance advantages due to their contributions of passive immunity. However, future research is needed to determine if these observations are consistent throughout the sow's reproductive lifetime.

Researchers: Erin Carney, Huyen Tran, Justin Bundy, Roman Moreno, Matthew Anderson, Jeffrey Perkins, Phillip Miller and Thomas Burkey, all of the University of Nebraska. Contact Burkey by phone (402) 472-6423, fax (402) 472-6362 or e-mail t[email protected].

Table 1. Treatment Effects of Sow Parity on Litter and Pig Measurements

Item Parity
1 4
Number of sows 19 24
Pigs/litter
Total born 12.79 12.79
Born live 12.00 11.50
Stillbirths 0.63 1.13
Mummified fetuses 0.16 0.21
Mortality (preweaning) 2.68 1.83
Weaned 10.16 10.13
Litter weight, lb.
Birth (Day 0) 15.73 17.89
Weaning (Day 19) 55.14 58.07

Experimental Vaccine Is Effective Against PRRS

A modified-live-virus (MLV) vaccine, propagated in an innovative porcine alveolar macrophage cell line, designated ZMAC, was effective in protecting pigs from porcine reproductive and respiratory syndrome (PRRS) virus.

Use of the ZMAC-grown, MLV vaccine prevented the weight loss observed in non-immunized animals within seven days after exposure to a highly virulent strain of PRRS virus.

“Remarkably, analyses of the virus load in serum and lung samples from PRRS virus-immunized and challenged animals revealed that the vaccine virus grown in ZMAC cells was significantly more effective at reducing the extent of viremia (the presence of virus in the blood) at seven days post-challenge, and also at eliminating virulent virus from their lungs by 10 days post-challenge,” says Federico A. Zuckermann, professor of immunology at the University of Illinois College of Veterinary Medicine.

The researcher says the degree of protection afforded by this vaccine “against a genetically divergent and highly virulent PRRS virus has important implications for the prospect of developing an effective vaccine against this pathogen.

“Namely, the results of this study suggest that the effectiveness of a PRRS MLV vaccine can be improved, and that it is not, as it is commonly believed, only determined by its genetic similarity to the challenge virus, but is also influenced by how it is produced.

“The results of this study provide great hope that an effective MLV vaccine against PRRS virus can be developed,” says Zuckermann.

The goals of this project, funded by the National Pork Board, were to use an innovative porcine cell line to produce a PRRS MLV vaccine, and to compare this virus' efficacy to that of vaccine made traditionally in the simian MARC-145 cell line, the only other type of cell line known to support the growth of PRRS virus.

To evaluate the vaccine potential of the ZMAC-grown virus, a standard immunization test was conducted. Six, 8-week-old pigs were injected with the Prime Pac commercial vaccine (Schering-Plough Animal Health) propagated in either ZMAC or MARC-145 cells, while two groups of three animals were not immunized and served as controls.

Four weeks later, all vaccinated pigs and one of the PRRS naïve groups were challenged with an “atypical PRRS abortion storm” virus.

The result was that the Prime Pac vaccine grown in either cell line proved equally effective at preventing weight loss by pigs exposed to virulent virus seven days earlier. (See Figure 1, where weight changes of non-immunized and vaccinated pigs at seven days after challenge with atypical PRRS virus are depicted.)

The vaccine virus grown in ZMAC cells, however, was much more effective than the one generated in MARC-145 cells at reducing the extent of infection and also at eliminating virus from the lungs at 7 or 10 days post-challenge.

Researcher: Federico Zuckermann, University of Illinois. Contact Zuckermann by phone (217) 333-7767, fax (217) 244-7421 or e-mail [email protected].