Time to Start Talking about PRRS Eradication

Veterinary panel agrees that any swine disease cleanup program must be producer-driven in order to achieve any measure of success.

Three leading swine veterinarians agree — it's premature to start an eradication program to deal with porcine reproductive and respiratory syndrome (PRRS).

“I don't think we are ready for it,” stresses Matt Anderson, DVM, Suidae Animal Health and Production of Algona, IA. “If we were voting on an eradication procedure today, I would vote against it. But I think we need to start talking about it — and it's possible we could be talking about it for three or four more years.”

Long-term, eradication of PRRS should be our goal, but there are a lot of steps along the way that need to be taken first, adds Keith Aljets, DVM, Veterinary Medical Center in Williamsburg, IA.

“I am in agreement with my colleagues,” adds Hans Rotto, DVM, Iowa State University (ISU) diagnostician, who previously served as a swine veterinarian with Christensen Family Farms in Sleepy Eye, MN.

The three swine veterinarians participated in an open-ended question-and-answer session on PRRS with producers at an Iowa Pork Congress seminar moderated by ISU swine veterinarian Locke Karriker.

Following are a few of the exchanges:

Serum therapy: The use of serum therapy or inoculation was a key question.

Anderson says his experience with the process has been quite good. He adds, “I think it is absolutely important that we get a naïve animal to start with, no matter where that animal comes from, and immunize it against the strain or strains that are present on your farm.”

Anderson's preferred way to use serum therapy is in early exposure to naïve gilts, providing them plenty of time to cease shedding the virus prior to entry into the sow herd.

Rotto says PRRS virus has a history of not being very efficient at infecting a herd. “We talk about farm-to-farm spread, yet we may have pockets in our breeding and gestating sows that have not yet been exposed to the virus. That's where we can use serum therapy — to help acclimate our gilts with the long-term goal of stabilizing the immunity of our sow herd.”

Aljets says that his experiences with a control plan utilizing serum therapy are similar to those he's had with the use of commercial PRRS vaccine and other control methods.

“Sometimes they work really well and sometimes they don't work at all,” he says. And he reminds that PRRS vaccine should be used in a similar fashion as serum.

If you are going to use vaccine, you need to be committed to its use and vaccinate entire populations of animals, not just a group or two of replacement gilts, notes Karriker.

None of the trio indicated they had experienced any disasters with the use of serum inoculation. But Aljets adds a note of caution for those using the process.

“The real question I have with serum injection is not when to start serum. I think the decision to isolate PRRS virus infecting a sow farm and inoculate replacement gilts is a valid one. The question I have is, when does the use of serum therapy end? This year you may have one strain infect your herd, and next year it could be another one. Do you drop one strain of the PRRS virus therapy because you haven't seen it for a few years?” he questions.

Before beginning serum therapy, you and your veterinarian need to consider when and how you will end the serum therapy procedure, adds Karriker.

Anderson agrees, and suggests that once a sow herd enters an “era of stability and we become confident that sow herd is no longer shedding virus to the pigs, and we have no herd cyclicity on the site, that's when we can begin to start thinking about stopping that injection program.”

Aljets also warns that if producers plan to inoculate their sow herds with PRRS virus, they need to make sure it is done with a resident virus found on the sow farm and not a PRRS virus that was just introduced into the sow herd. Serum therapy, if not done correctly, has the risk of introducing a new PRRS strain into the sow herd.

Anderson says Aljet's point cannot be overemphasized. “You need to know that the virus you are using to inoculate your sows is the one that is causing problems. When you hear about these strategies that have not been successful, sometimes I think there is a difference in the virus used for inoculation and the virus that caused the initial assault,” he surmises.

All three veterinarians agree that 8-12 weeks after serum inoculation, producers should start to see healthier pigs if proper farrowing protocols are followed that don't propagate PRRS virus in the farrowing barns.

“How you move pigs, handle fallbacks and crossfoster pigs will have an affect on whether you will wean PRRS-negative pigs,” comments Aljets. The more litters that are left intact, the shorter period of time you risk propagating the PRRS virus infection amongst the pigs in your farrowing barns, and the less problems there will be from PRRS serum therapy, he notes.

Anderson says by limiting the use of serum therapy to gilts, offspring seem to have more of a chance to thrive.

Above all, while serum therapy is a tool that can help control the PRRS virus, it is not without risks, stresses Aljets. “If you plan to use serum therapy, you need to discuss and understand those risks with your veterinarian.”

Injectable vaccinations: Because needles can increase the risk of spreading PRRS postweaning amongst nursery penmates, Anderson suggests producers consider switching to oral vaccinations and antibiotics for the control of secondary diseases like salmonella, ileitis and mycoplasma.

PRRS-mycoplasma organisms are well-known to work together to cause major financial problems to hog operations, Anderson continues. So producers may well need to vaccinate 2-4 weeks ahead of expected seroconversion to protect their herd from mycoplasma. An option would be to strategically use a number of antibiotic options if PRRS-mycoplasma infection appears to be breaking through vaccine protection.

Area spread and aerosol spread: Karriker says he receives lots of calls and hears much confusion about these two terms.

Area spread refers to the means — pigs, people, trailers, etc. — in which the PRRS virus moves from farm to farm.

Aerosol spread refers specifically to the ability of the virus to move by itself in the air or with wind currents from site to site.

Karriker's opinion is that aerosol spread occurs very, very rarely.

In contrast, area spread is a very common event that appears to be the result of several combined factors. He stresses producers should focus on what they can control and shore up biosecurity measures to slow area spread.

Biosecurity: “I think we have all underestimated the value of biosecurity, and I am not just talking about things like shower-in and shower-out, but things to protect the herd, like trailers and transport,” emphasizes Rotto.

Science shows that you cannot simply wash PRRS out of a vehicle, says Anderson. “We are talking about something that is a whole lot smaller than your average bacteria. Viruses are able to hide and survive in a moist environment for long periods of time.”

The panel agrees that proper washing, disinfecting and drying are necessary to rid trailers and trucks of the PRRS virus.

If producers are dealing with naïve pig populations, they should consider dedicating a trailer to that segment of production, says Rotto.

He also suggests producers should not let down their guard when it comes to biosecurity.

“Remember that most farms are naïve to another set of PRRS viruses, and sometimes a one-time capital investment in biosecurity can protect you, not just from PRRS, but from almost all other bugs.”

Above all, keep biosecurity simple and practical, and protect the sow source. Make sure gilts and semen are negative for PRRS, Rotto emphasizes.

Pork Board Appointments

Agriculture Secretary Mike Johanns has announced six appointments to the 15-member National Pork Board.

Six were chosen from among nine producers nominated by the National Pork Act Delegate Body during its annual meeting in Kansas City, MO.

Five appointees will serve three-year terms and one appointee will serve the remaining two-year term of Deborah Johnson from North Carolina.

Serving three-year terms are: Dianne Bettin, Truman, MN; Dennis Michael, Yankton, SD; Jeff Galle, Pittsfield, IL; Eugene Nemechek, DVM, Wilson, NC; and Randy Brown, Nevada, OH. Serving a two-year term is Alan Wilhoite, Lebanon, IN.

Targeted Feeding Boosts Sow Prolificacy

Computer-based lactation feeder moves sow productivity to a higher plane.

If you could find someone to manage sow feeding during lactation and boost number of pigs born/mated female/year by two, would you hire them?

Alain Lefebvre, owner of Aldo Farms, Inc. in St-Lambert-de-Lauzon, Quebec, challenged a feeder manufacturer to develop a feed management system to improve sow feed intake during lactation. His theory — more feed equals more milk; more milk equals heavier pigs at weaning.

Nine years later, development, refining and testing the computerized feed distribution system has delivered more than Lefebvre bargained for.

Drawing on his most recent seven years of PigChamp data (Table 1), he's quick to point out the multiplying effects the feed management system has had on his 1,700-sow herd:

  • Sows leave farrowing crates in better condition, confirmed by sow weight and backfat measurements;

  • Better condition of newly weaned sows lowered feed demands in gestation by about 1/2 lb./day;

  • Wean-to-first service estrus was shortened by one day;

  • Pigs weaned/mated female/year climbed to 29, and currently stands near 28; and

  • Sow lifetime production was extended by one parity, now averaging 3.5.

Testing the Theory

Lefebvre's interest in sow condition piqued in 1999 while reviewing a French swine industry magazine article, which set optimum backfat levels between 16-20 mm. (0.62-0.78 in.).

Soon after, he began a sow condition study at Aldo Farms to establish the best backfat range to maximize sow performance. His ongoing study measures backfat thickness when sows enter and exit the farrowing crate. The measurement is taken at the last rib, 2.5 in. off the midline, with the location marked in permanent ink to ensure both measurements are taken at the exact location. Sows are weighed on the same schedule.

Lefebvre's challenge to develop a lactation feed management system went out to Jyga Concepts, Inc., St-Nicolas, Quebec. His goal was to record accurate feed intake during lactation and determine correlations to production records typically collected for PigChamp recordkeeping. Since 1999, the database reflects over 15,000 farrowings and over 30,000 sow-weighing and backfat measurement events.

Six months into the study, sows with backfat measurements between 14 and 20 mm (0.55-0.78 in.) had relatively stable total pig born averages, but sows with 21-32 mm (0.82-1.25 in.) backfat were much more erratic. He also realized the impact of lactation length on backfat depletion was more or less controlled by how much the sows ate.

Additionally, he noted that feed intake/day was affected slightly by number of piglets, but eventually it plateaued. It was that plateau that signaled the feed intake potential of the sow, he says.

Eighteen months into the study, Lefebvre noted the benefit of increased feed intake during lactation on total pigs born in the following litter was 0.3 pigs for each additional pound of feed consumed/day. He also observed that as daily feed intake in lactation stabilized at 14-15 lb./day, total pigs born in the subsequent litter stabilized, and backfat loss of 2 mm. (0.10 in.) during lactation was predictable.

At the outset of the study, Lefebvre noted sows that commonly lost 8 mm (0.30 in.) backfat during lactation, averaged 11.1-11.3 pigs born (10.2 live) in the next farrowing. Today, after several years on the computer-controlled feeders, sows average at least 13 pigs born (12.1 live) with backfat loss reduced to 2 mm (0.10 in.). Average age at weaning is just over 16 days (See PigChamp data, Table 1).

When backfat losses exceed the 2 mm. target, total pigs born in the subsequent litter drops 0.2 pigs/litter with each millimeter loss in backfat, he says. The Aldo Farm study also showed that sows entering the farrowing crate in excess of 20 mm. (0.78 in.) of backfat consumed 0.22 lb. less feed/day during their stay. “The lactation-gestation cycles are linked,” he reinforces.

System Refined

With numerous refinements made to the Gestal feed management system during nine years of development, Jyga Concepts electrical engineer Yves Drouin feels confident the system can effectively hit the backfat/sow condition and feed intake parameters needed to maximize performance in each lactation.

“This tool will help manage all of the sows in the herd on an individual basis,” he says.

The individual attention is delivered through computer-calibrated, daily feeding curves. At the heart of the feed management system is a patented, sealed, polyethylene farrowing crate feeder with a capacity to store 26-28 lb. of feed. Feed from the storage bin is rationed to a smaller hopper in 2-lb. increments. The sow calls for feed from the hopper by flipping an agitator in the feeder. A sensor in the trough will not allow the sow to call for more feed if some remains in the trough.

Feeding periods are commonly broken into four, three-hour time periods, beginning at 6 a.m. One-hour breaks are usually set between the feeding periods. The last feeding period for the day concludes at 9 p.m. No feed is available until the cycle starts over again the next morning. The feeding periods are flexible, allowing up to eight feeding periods per day.

Generally, the three-hour feeding periods are broken into 15-minute intervals. If a sow eats 2 lb. of feed in five minutes, she must wait 10 minutes before the hopper is replenished with two more pounds of feed. This “rationing” throughout the day ensures fresh feed is always available, and records the eating pattern for every sow, every day, through the system's software program.

A daily feed consumption report, available through a central computer, allows the manager to see each sow's feeding activity during the designated feeding periods.

This individual feeding information is presented two ways. One is the “farrowing sows' consumption” report (Figure 1), which lists each sow's identification number, crate number, the length of her lactation (to date), her assigned feeding curve, her feeding schedule, maximum projected feed consumption and the total amount of feed delivered (to date).

At the far right of the report are blocks representing feeding periods, which are colored in green, yellow, white and red. These colored blocks provide a quick update on each sow's daily feeding pattern.

A green block indicates the sow is eating at the targeted level.

White blocks indicate feed disappearance is exceeding the target. This means one of two things — either she can eat more than she's receiving and her daily allocation should be bumped up, or she is wasting the feed.

A yellow block signals that the sow is eating less than expected. This is an early warning. Successive yellow blocks warrant investigation.

A red block or an “x” indicates the sow did not eat during the allocated feeding period. Successive red blocks alert the manager to check the sow and the feeder. This may indicate she is farrowing.

Generally, the farrowing manager will review the sow eating patterns first thing each morning. If the first feeding period begins at 6 a.m., sows are usually hungry because they haven't eaten overnight. Arriving at 8 a.m., the manager will take note of the sow and crate numbers with white and red blocks. This allows him/her to pinpoint poor consumption patterns and those sows requiring more feed. If a sow is wasting feed, space between delivery periods can be extended so she learns that if she wastes it, it may be awhile before she gets her next meal.

Next, the manager calls up a second graph that provides a real-time snapshot of a sow's feed consumption each day during her lactation. (Figure 2). The red, yellow, green and white sections reflect feed intake during the four feeding periods. The blue line reflects the composite daily feed intake for Sow #0579, for example. The goal is to keep the blue line near the middle of the white section, thus meeting the sow's feed needs. If the blue line moves above the white section, her daily allocation should be increased. If it slips into the green, yellow or red areas, feed allocation should be adjusted accordingly. Severe slippage should be investigated.

After a herd has developed an adequate database, many have found it helpful to develop basic feeding curves for first parity, second parity and 3+ parity sows to serve as guidelines to allocate feeding levels for sows entering farrowing crates.

Ohio Experience

Tom and Galen Harrod of Greenville, OH, have been working with the Gestal prototype feeders in their 350-sow herd for just over a year.

“The first thing I do in the morning is check for the Xs,” explains Galen. He makes a list and checks those sows first. Some aren't eating because they're farrowing. Occasionally, a feeder will get plugged, so that's remedied. If a sow simply quit eating because she's not feeling well, remedies are sought.

Next the Harrods check the feed consumption graphs to ensure the blue line is within the upper parameters of the white section of the graph. If consumption slips, daily feed levels are lowered.

“The great thing about this feeder is the sows will tell you how fast they want to come back,” notes Galen.

Returning to Sow #0579, the graph (Figure 2) shows she's in her 14th day of lactation and 188 lb. has been dispensed to her, for an average of 13.5 lb./day.

The database allows the operator to check previous lactations, too. For example, he notes her feed consumption dropped between Days 7 and 9. Checking back, he can see this is a normal feeding pattern for this sow. “It's amazing how consistent they can be from lactation to lactation,” he observes.

Tom Harrod says weaning weights have stabilized at 11-12 lb. for pigs weaned at 15-16 days of age. “Being able to feed the sow according to her needs and wants actually helps improve pig weights at weaning,” he says. “The best sows, the top 5-8%, will stay in the white area (of the graph). Those are the sows you need to watch because they can eat more.

“The biggest thing I like about the feeder is I know what the sows are eating and they are getting all they want. And, when I'm busy in the fields, I know the sows are being taken care of, even if I can't check them until later in the evening or the next morning,” Tom adds.

No Time Off

Lefebvre says besides being an excellent sow management aid, the lactation feeder doesn't take weekends and holidays off.

“Oftentimes, your best manager is not feeding the sows on weekends and holidays, which actually accounts for 30-35% of the time,” he points out. “This system will do the job better and more consistently than anyone. It's like hiring the best feed management person you can find and putting him/her in your barns 24 hours a day.”

Returning to the PigChamp data, Lefebvre notes that the “pigs weaned/lifetime female” has risen from a range of 37-50 in the early days of testing the Gestal feeder, to the mid-60s in 2003-2004. Slippage in 2001 was caused by a porcine reproductive and respiratory syndrome (PRRS) outbreak.

The Gestal system has evolved through several modifications to improve the feeder's reliability and cut costs. Currently, the system can be installed for an average price of about $600/farrowing crate. A standard desktop computer drives the software feeding programs.

Table 1. PigChamp Performance Monitor for Aldo Farms, Inc.
Jan 991
Jun 99
Jul 99
Dec 99
Jan 00
Jun 00
Jul 002
Dec 00
Jan 01
Jun 01
Jul 01
Dec 01
Jan 02
Jun 02
Jul 02
Dec 02
Jan 03
Jun 03
Jun 03
Dec 03
Jan 04
Jun 04
Jan 052,3
Dec 05
Breeding Performance
Total number of services 2,647 2,515 2,460 2,447 2,442 2,598 2,399 2,404 2,399 2,385 2,380 4,986
Weaning-1st service interval 5.6 6.6 5.7 6.8 6.5 6.1 4.9 4.8 4.7 4.7 4.9 4.8
Percent sows bred by 7 days 93.6 87.7 92.8 86.0 90.4 92.1 96.4 96.0 97.0 97.0 95.5 96.4
Farrowing Performance
Number of sows farrowed 1,956 2,119 2,079 2,068 2,121 2,064 2,147 2,141 2,142 2,177 2,150 4,224
Avg. parity of farrowed sows 5.1 5.6 5.8 4.6 3.6 3.9 4.3 4.5 4.6 4.5 4.5 4.3
Average total pigs/litter 11.3 11.1 11.1 11.5 12.1 11.9 12.6 13.0 13.0 13.0 13.0 13.1
Average pigs born alive/litter 10.3 10.2 10.2 10.7 11.3 11.1 11.7 12.1 12.0 12.1 12.1 12.1
Farrowing rate 75.2 79.1 84.3 84.3 86.4 82.9 86.2 88.4 90.2 89.3 90.4 84.2
Litters/mated female/year 2.45 2.48 2.50 2.50 2.51 2.47 2.56 2.56 2.60 2.58 2.59 2.52
Weaning Performance
Pigs weaned/mated female/year 22.8 22.9 23.2 24.6 26.7 25.5 27.2 27.8 28.5 28.7 28.0 27.6
Pigs weaned/lifetime female 37 50 62 59 42 41 53 53 60 64 64 61
Population
Average parity 4.5 4.9 4.0 2.7 2.9 3.3 3.5 3.7 3.5 3.5 3.5 3.4
Avg. female inventory 1,649 1,666 1,668 1,676 1,712 1,700 1,690 1,688 1,698 1,683 1,695 1,752
Avg. non-productive sow days 43.1 39.5 40.5 44.2 39.9 44.2 32.5 33.6 31.5 30.9 31.5 36.0
1 January 1999 to June 2000 adjustment period as original Gestal feeders were installed.
2 July 2000 to June 2001 and Jan.-Feb. 2005 outbreaks of porcine reproductive and respiratory syndrome impacted breeding herd performance.
3 2005 presented for 12-month period; all other data presented in six-month increments.
Figure 1. Farrowing Sows' Consumption
Sow Crate Day % Curve Schedule Received Maximum Distribution %
0579 W6 14 100 High Litter 2 1 hour 12.25 15.09 93
0577 W7 10 100 High Litter 2 30 min. 8.34 14.40 66
0584 W8 9 110 High Litter 2 30 min. 11.72 15.36 87
0692 W9 14 100 High Litter 1 30 min. 10.06 11.81 97
0612 W10 8 100 High Litter 2 30 min. 11.28 13.62 95
0539 W11 9 100 High Litter 3+ 30 min. 8.73 13.11 76
W12 0 0 0 0
0542 W13 6 100 High Litter 3+ 30 min. 9.94 11.64 98
0540 W14 5 100 High Litter 3+ 30 min. 9.94 11.64 98
0620 W15 6 105 High Litter 2 30 min. 10.95 13.13 95
0400 W16 6 100 High Litter 3+ 30 min. 7.77 11.64 76
0543 W17 6 100 High Litter 3+ 30 min. 9.94 11.64 98
0329 W18 6 100 High Litter 3+ 30 min. 6.07 11.64 60
0705 W19 7 100 High Litter 1 1 hour 5.47 9.83 64
0110 W20 7 100 High Litter 3+ 30 min. 7.18 12.41 66
0348 W21 4 100 High Litter 3+ 30 min. 2.20 11.47 22
0229 W22 4 100 High Litter 3+ 30 min. 6.64 11.47 66

FDA Removes Weight Restriction on Paylean

The change to the feed label provides added marketing flexibility.

The U.S. Food and Drug Administration (FDA) has approved a label change for Paylean, a Type A medicated feed article for swine.

The new approval permits Paylean to be fed to pigs weighing at least 150 lb. during their final 50 lb. to 90 lb. of gain, regardless of market weight. Prior to the change, the label allowed the use of Paylean in pigs weighing up to 240 lb.

The new label (available at www.elanco.us or 800-428-4441) also stipulates Paylean be fed between 4.5 g. to 9 g./ton of feed in a complete ration containing at least 16% crude protein. The label also notes that recent clinical registration data suggests no statistical difference between the effects of the 4.5- and 9-g. level. Also, the 18-g./ton feeding level has been removed.

The change to the Paylean label provides increased marketing flexibility for producers seeking to match packer weight preferences, according to Elanco. It also reaffirms the product's efficacy at the 4.5- and 9-g. level when fed to any market weight.

Paylean has a zero withdrawal time prior to slaughter.

Liquid Solutions for Weaned Pigs

TechMix, Inc. introduces two new liquid solutions for transitioning weaned pigs to dry feed. Blue 2 liquid provides energy, electrolytes and acidification by replenishing critical nutrients when pigs are stressed, sick, being weaned or just not eating. Enriching the pig's water with Blue 2 stimulates intake and helps rehydration. The solution may be administered through standard medicators. Also released recently is Blue Mist, a unique aromatic, spray-on attractant to help pigs make the move to dry feed, improve feed intake and adapt to their new source of water at weaning. Hand-held sprayers make application to feed and water quick and easy. Go to www.techmixinc.com or call the TechMix Swine Hot Line at (320) 562-2740.

Ultrasound Pregnancy Scanner

The PalmTop Ultrasound Scanner from Veterinary Sales & Service, Inc. features 3.5 and 5.0 MHz sector probes with freeze buttons. Scanning depth is variable up to 7.6 in. The new, removable battery eliminates the external battery and cable and has a two-hour, continuous-run capacity. Convenient handle design provides for easy transport and viewing. The PalmTop has enhanced durability, weighs less than 2 lb., and provides high resolution images for quick and easy diagnosis. Call (888) 234-5999 or visit www.vetsales.net.

Electronic Tracking System

Available from Farnam Companies, Inc. is the new Farnam portable Radio Frequency Identification (RFID) Tag Recorder. The unit is a rugged, sealed Palm-based Personal Digital Assistant with an integrated RFID reader and data accumulator designed for a variety of applications in livestock identification. It functions as a stand-alone unit in the field and comes with a user-definable software interface that can be customized with multiple sets of data collection fields to suit individual needs. Data collection fields can be switched without downloading data to a PC or laptop first. Getting data from the reader into a computer is easily done through the Palm HotSync software. Call (800) 511-4744 or visit www.farnam.LTs.com.

GPS Irrigation Systems

Reinke Manufacturing, Inc. has received patent certification for two of its Navigator Series of global positioning system (GPS) controls. The Navigator Swing Arm Corner and the End of System GPS systems offer the only GPS-controlled option available for irrigation systems in the industry today. The controllers increase accuracy, resulting in more precise irrigation practices. Reinke has also applied for certification of its GPS guidance for lateral move systems. Call (866) 365-7381 or visit www.reinke.com.

Breeding Solutions

Newsham Genetics has teamed with Gentec NV to manage the IGF2 gene for enhanced reproduction in the breeding herd and desirable lean traits in market animals. IGF2 is the first genetic marker that aids the selection of both dam and sire line traits in different directions to enhance dam line selection for the production of larger litters or the selection of a greater muscle mass in sire lines. The management of the IGF2 genotype in the SuperMom female and the SuperSire terminal boar lines will provide positive benefits to the maternal production herd and the terminal offspring sold to market. Contact Fields Gunsett at Newsham at (515) 225-9420 or e-mail Fields_Gunsett@newsham.com.

Send product submissions to Dale Miller, Editor (952) 851-4661; dale.miller@penton.com

Unraveling the Litter Size Riddle

Farrowing managers measure success by the number of live pigs produced for each pregnancy.

Confounding this measure of success is the miracle of physiology, which requires the harmonious functions of the sow, the boar, the sow's uterus, the fetal piglets' placentas and the fetal piglets themselves. Adding to the mystery, much of the process is invisible to the producer.

Knowledge of the contribution of each can improve sow performance.

The number of live piglets produced by a sow is limited by ovulation rate, the number of ova or eggs shed during each estrous cycle. From this upper limit, the number of live born piglets is progressively whittled away due to failure of sperm to fertilize the ova (5-10%) and loss of developing embryos before the 30th day of pregnancy (about 20%).

Although fertilization failure and embryo death represent losses of live pigs, both can be overcome by increased ovulation rate — through genetic selection for the trait, for example — resulting in more live embryos in the uterus on Day 30 of pregnancy.

In contrast, uterine capacity — defined as the number of piglets a sow can support during pregnancy — also limits the number of live piglets born. This limitation cannot be overcome simply by increasing ovulation rate.

So, for practical purposes, the number of piglets born alive is determined by the least limiting of two factors — ovulation rate or uterine capacity.

The sow's uterus, the fetal piglets' placentas and the fetal piglets themselves combine to influence the number of fetal piglets the sow can support during pregnancy.

The uterus provides the nutrients needed to support the fetal piglets. The placentas transport those nutrients from the sow to each developing piglet. The efficiency of each function influences the number of piglets born alive.

Improvements in any of these functions improves litter size, as long as ovulation rate is greater than uterine capacity. For maternal line sows available today, the average ovulation rate is typically greater than the average uterine capacity, even after accounting for losses due to fertilization failure and embryo death.

Piglet Blood Supply Study

For the last 10 years, our research has focused on the contribution of the fetal piglet blood supply to uterine capacity. Fetal piglet red blood cells carry oxygen from the placenta to the various parts of the fetal piglet, and return carbon dioxide from those parts to the placenta, where it is transferred back to the sow for disposal.

Our results have shown that individual fetal piglets differ in their hematocrit, which is a measure of the proportion of blood made up of red blood cells. More importantly, we have shown that hematocrits are lower in small fetal piglets during pregnancy.

The size of the fetal piglet is progressively reduced as litter size increases. Therefore, fetal piglet red blood cells are fewer in small fetal piglets from large litters during pregnancy.

Since the availability of oxygen and the removal of carbon dioxide are essential to piglet survival during pregnancy, based on these results, we suggested that suppression of the fetal piglet red blood cell supply in large litters contributes to piglet losses due to limitations in uterine capacity.

We reasoned that if impaired fetal piglet blood supply contributes to decreased uterine capacity, differences in genes that increase fetal piglet blood supply would increase uterine capacity and litter size.

A hormone called erythropoietin, which interacts with a hormone receptor called the erythropoietin receptor, primarily controls blood supply to the fetal piglet, like other mammals. Together the two proteins, increase the production of red blood cells.

We explored the erythropoietin receptor gene for genetic differences that might increase its function. We found a change in the gene that we predicted would increase production of the receptor and, subsequently, lead to increased red blood cell production, greater uterine capacity and litter size.

Recently, we've shown this change in the gene is associated with increased uterine capacity and the number born alive in two different pig populations at the U.S. Meat Animal Research Center. The change in the gene was relatively rare in both populations.

The increase in uterine capacity and litter size was found to average between one and two piglets/litter, depending on the experiment and population. These results indicate that this change in the erythropoietin receptor gene could be used as a genetic marker to select for improved uterine capacity and litter size.

Energy, Corn Concerns

Livestock producers could soon face a double whammy: continued high energy prices and a shortage of corn for feed.

“The corn surplus will be gone with the 2006 crop, as expected total corn use may exceed production by about one billion bushels,” says Chris Hurt, Purdue University Extension marketing specialist.

Animal agriculture will also face increasing competition for the use of that corn as more corn is diverted to fuel.

“The rapid growth of the use of corn for ethanol in the coming months and years means that the livestock industry has a new major competitor, at least for corn,” notes Hurt, meaning that low-priced sources of feed may be fading, but uncertainties remain.

The New War on PRRS

The American Association of Swine Veterinarians (AASV) assumes the leadership role in trying to wipe out this devastating pig virus.

AASV President Scott Dee of the University of Minnesota says the group's stance stems from last fall's position statement calling for eradication of the porcine reproductive and respiratory syndrome (PRRS) virus as a long-term goal.

Economics justify action, he says. A National Pork Board study projects PRRS costs the pork industry an estimated $560 million annually (in 2004 dollars). That's not new. Less well known is that 88% of the costs occur postweaning, he says.

Four Key Points

Dee also cites four key PRRS points:

  1. “This action is a long-term goal, led by pork producers and the AASV.”

    The voluntary effort might take 20 years to complete. The first five years will focus on answering research questions that he believes “will lead to elimination of this pathogen and keep it out of farms at a higher rate of success.”

  2. “This will definitely be an industry-driven and not a federal government, regulatory-driven approach,” he says.

    “We think if producers and practitioners work together, we can do this (eradication) as a team, without the regulations imposed on us,” says Dee, co-director of the university's Swine Disease Eradication Center.

    But the next five years will be critical as a time to build teams and confidence needed to accomplish the task ahead, he says.

  3. Continuation of small-scale regional eradication projects will provide a testament to producers' ability to work together, as is being done in Minnesota and North Carolina.

    “Producers need to work together in designated areas, communicating and sharing information and talking about cleaning up areas rather than individual farms,” says Dee.

  4. A model for successful team-building started in Ontario, Canada. Dee visited producer and veterinary groups there while serving as president-elect of the AASV. He returned to set up similar models in Minnesota, which is now the first state to have developed an industry-wide PRRS eradication task force.

PRRS Eradication Task Force

From that start, came consensus for broader formation of the North American PRRS Eradication Task Force, approved by the AASV PRRS Committee at its recent annual meeting in March in Kansas City, MO.

AASV PRRS Committee chair Monte McCaw, DVM, North Carolina State University, led the group's first official meeting at World Pork Expo in early June in Des Moines, IA, in mapping out goals and a plan of action. The task force will act as an oversight group for maintaining and enhancing communications between the United States, Canada and Mexico, says Dee.

Also during the meeting, updates were presented on eradication efforts in Minnesota, North Carolina and Ontario.

Bob Rowland of the University of Minnesota discussed the role of university research in PRRS elimination.

In that regard, Dee and Jeff Zimmerman, DVM, of Iowa State University began a year-long collaborative research project on June 1 at the University of Minnesota's research farm in the west central part of the state.

“The objective really is to see if we can raise negative pigs in an endemically infected region,” says Dee. The farm will have PRRS-infected populations of pigs in facilities, with negative groups of pigs only about 300 ft. away. Research will measure the effectiveness and impact of different levels of biosecurity on the PRRS-negative pigs.

“We are going to see if we really know how the virus is spread, and if we can keep it out with these different facilities practicing different levels of biosecurity,” he notes.

“We should obtain results that will help us to better define aerosol spread and area spread and also transmission specifically by insects, fomites, personnel — all the routes we feel are important, while identifying the routes that are the most high-risk.”

The study is not only unusual in its length (one year), but also in that it involves 2,000 pigs, a large number for a research study, suggests Dee. He is taking a six-month leave to focus exclusively on this research endeavor.

“We hope to develop concrete answers on how the virus spreads and how to keep it out,” he says.

Another means for deriving those answers is a PRRS risk assessment tool provided to AASV members by Boehringer Ingelheim Vetmedica, Inc. The computer-driven tool will be used in research projects this summer to evaluate risk factors in spread between farms, and could prove to be a valuable key in assessing farm biosecurity and management in deterring exposure to the PRRS virus.

Animal ID Setback

The National Animal Identification System (NAIS) suffered a setback in May.

When members of the U.S. House of Representatives passed an $18.4 billion agriculture appropriations bill for 2007, they effectively presented the USDA with a caveat — no money will be allocated to the NAIS until the House Agriculture Appropriations Committee receives more details on the proposed program's costs, evaluation procedures and the need for legislative changes.

At this writing, the Senate had not voted on ag appropriations for 2007. If they fund NAIS, the appropriations committees from the House and Senate will eventually have to reconcile the differences.

Frustration Prevails

“Frustrating” pretty well sums up the feelings on both sides of the animal identification (ID) debate.

Several House members blame USDA for dragging their feet in providing the costs and working procedures for a national animal ID program. Some have implied that certain not-to-be-named sectors in the livestock industry lobbied for the hoop-jumping exercise to slow the progress of the national program.

Secretary of Agriculture Mike Johanns has publicly stated that a livestock identification program could be voluntary, with two big “ifs.”

If too few livestock owners chose to participate, the program may become mandatory. And, if most livestock owners chose to participate, but some laggards remain, the program may become mandatory.

Somewhere in the middle, the livestock industries probably can buy some time, but the message is clear — the U.S. livestock sector needs an identification program that provides quick, effective traceback capabilities, and the agriculture secretary is committed to delivering one.

Bottom line — it's really not optional; it's essential.

In an odd way, the resistance to individual animal identification reminds me of a card I recently received from the state department of transportation. The notification reminds me it's again time to renew my driver's license. Truth is, it's a hassle. But, to their credit, they want to make sure I can still see well enough to drive, to document my insurance coverage, and (groan), to get a new picture, sure to verify that I am not aging all that gracefully.

Yea, it's a hassle, but it's essential.

By comparison, the first step in the national animal ID program is no hassle at all. Simply go to http://animalid.aphis.usda.gov/nais/index.shtml for more information about the NAIS and for premises registration.

The USDA's goals are straightforward and worthwhile — establishment of a fully functional animal identification system to safeguard U.S. animal health. And, in the event of a disease outbreak, the system must be capable of pinpointing where a disease was detected, then trace all movements of any animal back to the farm of origin within 48 hours.

Beware the Nay-Sayers

There are certain factions in the pork industry that do not support a national ID program because they see it as a financial and management “burden” with little or no financial reward.

In a few cases, these anti-ID folks are breeders and caretakers of minor and/or rare breeds of animals and poultry at risk of extinction.

On the hog side, some simply supply pork to a niche market with no aspirations to expand their market. That's fine, but their limited aspirations seem to have obstructed their view of the potential disease risks lurking out there.

Preservation of a broad genetic base is important as our growing knowledge of gene markers and the potential for selection for productivity gains, meat quality and disease resistance advances.

In the event of a foreign animal disease outbreak, containment and rapid response are keys to restricting the spread. Yes, it could create a real expense — genetically and financially — to those experiencing an outbreak, but it pales in comparison to the costs of a disease left to spread unchecked.

Surveillance and a highly connected reporting network are the first steps to disease containment. Willingness and ability to impose and undergo quarantines will determine the effectiveness of containment efforts.

Moving On

A primary area of contention is data confidentiality of NAIS information.

Understood. We all live in fear of identity theft or “big brother” gaining too much access to our personal lives. A recent failure to safeguard the personal identification information of our armed services veterans certainly doesn't build confidence.

But I agree with the National Institute of Animal Agriculture's (NIAA) stance on the confidentiality matter, which is: “NIAA supports the exemption of NAIS data information from public release under the Freedom of Information Act so livestock stakeholders are assured their business in formation is kept private.”

For your benefit, and that of your industry, support the national ID program.

Lessons in Perfecting Pig Survival

Raised decks improve weaning weights — including the pigs left on the sows.

For 52 consecutive weeks, Pig Palace of Defiance, IA, has set the pace, ranking first out of 212 farms with 400,000 breeding females in Swine Management Services' Swine Smart Farm Benchmarking program for reproductive performance.

In the last year, Pig Palace has led the way by averaging 27.63 pigs weaned/mated female/year, proudly reports Steve Huegerich, general manager of the swine division of Juergens Produce & Feed Co., based in Carroll, IA.

And the 1,200-sow, farrow-to-wean farm achieved that top performance without extending weaning age. Average age and weight at weaning are 19.5 days and 14.6 lb., respectively.

Huegerich believes it is within their reach at Pig Palace and Pig Haven, a 3,000-sow, farrow-to-wean farm at Glidden, IA, to achieve nearly 30 pigs weaned/mated female/year by bumping weaning age to around 21 days.

Starts with Gilts

PigChamp data in Table 1 amplifies the solid performance at Pig Palace. “For the last 12 months, our born alive was 12.1 and our weaning average was 11.1,” states Huegerich.

It all starts with the gilts, he professes. Single-source Danbred gilts are purchased from an isolated farm in Kansas. “We treat the girls right and bring them in as selects at 240-250 lb. We hold them for 90 days before we breed them at 325 to 340 lb.”

All gilts are given a serum injection for porcine reproductive and respiratory syndrome (PRRS) upon arrival, and a killed, autogenous vaccine booster for PRRS upon herd entry. Gilts/sows are also vaccinated periodically for swine influenza virus, which cycles through the herd occasionally, he explains.

Gilts are never bred early. “If they are bred too young, they will not stay in the herd as long, and they will never produce as many pigs over a lifetime,” Huegerich observes.

Proper gilt management has resulted in a 96% farrowing rate; all gilts are artificially inseminated.

CLICK HERE TO VIEW TABLE 1 IN A NEW WINDOW

Decks Elevate Performance

Huegerich stresses that having a 12.1 born live average is the key to successful pig production: “You can't raise them if you don't have them.”

That high birth rate presents challenges, however. “It is difficult to expect those gilts to raise that many pigs,” he says.

Pig Palace sow manager Mike Rauch recalls employee efforts to save pigs.

“There has been a lot of bump weaning to do, sometimes moving hundreds of pigs from room to room. We got to the point where we were putting pans of milk in the farrowing crates to try to get extra nutrition into the pigs without having to do all of that extra work of moving pigs,” he says.

Even with the extra effort, the results were fairly poor, he laments. Preweaning mortality still hovered around 11-12%.

Instead of moving groups of newborn pigs to different sows, Pig Palace staff tried three different raised deck systems before finally settling on The Birthright Deck from Ralco Nutrition, Inc., in January 2005.

The deck consists of a totally enclosed, corrugated plastic box bolted on a frame above two farrowing crates. It provides a comfortable, heated environment, much like the home that newborn pigs just left, according to the Marshall, MN-based company. It features a front sliding door for pig entry, one or two heat lamps and plastic-coated, woven wire flooring. Two milk replacer cups are located at the front of the deck, along with adjacent nipple waterers. Decks have side vents for airflow.

Due to the Birthright Deck and other management factors, preweaning mortality quickly dipped to 7-8% and stayed there. Rauch's goal is 6%.

Huegerich and Rauch calculate the raised deck technology is responsible for at least 2-3% of the drop in preweaning mortality. Figure 1 shows a history of the farm's preweaning mortality rates before and after the decks were installed.

Deck Management

At Pig Palace, smaller pigs that are not competitive are pulled from a litter and placed in the raised decks at 3-4 days of age, says Huegerich.

“It allows us to save 95% of those pigs; we are saving 21 extra pigs a week, and we are getting a half-a-pound heavier weaning weight on the pigs that are not on the raised decks,” he adds.

There are several reasons for waiting until Day 3 or 4 to pull pigs:

  • It gives staff time to discern which pigs are truly becoming disadvantaged and in danger of falling behind, says Huegerich.

  • At Day 4, pigs are castrated, so it prevents handling pigs twice.

  • And, compared to hours moving pigs for bump weaning and crossfostering, it only takes 10-15 minutes to transfer them to the raised decks, notes Rauch. Most pigs are moved to decks in the same or adjacent farrowing rooms to try to maintain group identity.

Rauch warns against waiting too long to move small pigs to decks. Once pigs get gaunt in the flank, they need to be transferred.

“If we wait until they get thin in the back legs, then it is hard to make a decent pig out of them,” he comments.

At Pig Palace, there are 1-2 decks located in each of the eight, 20-crate farrowing rooms and 3-4 decks positioned in each of the two, 40-crate farrowing rooms. Ralco Nutrition suggests placing 12-15 pigs/deck. Huegerich says they've had no problems with 15 pigs/deck.

Milk Replacer

The Pig Palace uses Ralco's milk replacer, Birthright Baby Pig Milk supplement. They are also testing Solustart milk replacer from Purina Mills, explains Huegerich.

The milk product is plumbed to the decks from a mixer tank in the farm's office. Milk flows continuously through tubes to cups in the decks to provide pigs with 24-hour access.

Because of cost of the milk, and to speed transition to dry feed, the milk cups are removed and pigs are switched to creep feed at 10-12 days of age (about 10 lb.) as depicted in the picture above.

“We don't normally creep feed in the farrowing crate, so the little guys actually get access to dry feed before their bigger littermates,” points out Huegerich.

Managing pigs in decks is fairly simple, he says. Make sure the milk stays fresh. Keep pigs warm and as dry as possible. Adjust heat lamps and add drying powder as necessary, he says. Dip incoming pigs' noses into the cup once so they know where the milk is. Pigs in decks retain group behavior and all want to drink at the same time.

With the cups, pigs always have access to milk, so even the most timid pig gets a chance to drink the milk supplement, states Rauch.

Milk is mixed daily to keep it fresh and stirred automatically about every half hour in the tank to keep it from settling out, says Rauch.

The milk is also supplemented with Regano, an oregano product from Ralco, to help keep the milk stable and fresh, adds Huegerich.

“It provides extra insurance, and we haven't had any trouble with scours in the decks, so we feel the Regano is working,” notes Rauch.

Milk lines are cleaned weekly, including a regimen of soaping, disinfecting with acid and rinsing, Rauch explains. Decks are washed out and sanitized between groups.

Tracking Pig Quality

Huegerich says some groups of pigs from the decks are marked with a special notch or hole punch in their ears so they can be tracked for performance through grow-finish. Without the identification, it would be nearly impossible to spot these formerly small pigs, he says.

“It doesn't do any good to save those pigs in farrowing if they are not going to meet your standards when they go to the nursery or grow-finish site,” he adds.

Economics of Pig Decks

Adding the decks benefited overall weaning weights, including the pigs left on the sows. “Every pig in the system last year was a half a pound heavier at weaning. We are now at 14.6 lb. on 19.5 days weaning. We were at about 14 lb. before we instituted the decks,” says Huegerich.

The additional half-pound weight gain translates to a $9,100 advantage. Calculating the value of the pigs saved, minus the cost of the milk program, provides nearly a $14,000 net benefit/year from using the raised deck system (Table 2). The capital cost of the deck system is not included in the calculations. He estimates the decks will pay for themselves in about two years.

Additional Benefits

Feeding the small pigs in decks has created other benefits that Huegerich hasn't placed a value on.

“Our wean-to-service estrus interval went down by one-half day to a day because there were less pigs on the sows during lactation. Sows are maintaining their bodyweight better, increasing their born alive the next turn and increasing their farrowing rate, and we are just ending up with a better-conditioned sow going back into breeding,” he says.

Wean-to-estrus interval is 4.9 days, with 96.4% of sows bred back by seven days.

Other Factors for Productivity

Pig Palace feeds a highly fortified Purina premix to the breeding herd, including added levels of organic selenium and chromium to enhance performance.

It doesn't often pay to cut feed costs because it can also hurt feed quality, which will in turn hurt reproductive performance.

“A sow eats a ton of feed a year, and spending $5-6 extra on a ton of feed is not a big-dollar issue, especially if you spread that cost out over a number of pigs produced,” says Huegerich.

Facilities at Pig Palace are well maintained. Most of the buildings were rebuilt or remodeled following a fire in 1991. Farrowing areas are converted from nurseries. When the site doubles to 2,400 sows this summer, farrowing will be done in new buildings that will enhance pig production, he says.

CLICK HERE TO VIEW TABLE 1 IN A NEW WINDOW

Rescue Decks Save Unthrifty Pigs

Litter sizes are on the rise, in some cases dramatically. But when that occurs, it can lead to lower birthweights and more starving pigs, says Kevin Cera, swine nutritionist and director of Technical Services for Akey Feeds, headquartered in Lewisburg, OH.

If they do survive, they often end up being lightweight or compromised pigs at weaning simply because of the competition for milk, exacerbating preweaning mortality, he adds.

Crossfostering and bump weaning can become excessive and tie up crates, and moving to an older weaning age doesn't eliminate the problem of excessive preweaning mortality, says Cera.

Fallout Pigs

Two classes of fallout pigs impact preweaning mortality and number of high-quality pigs weaned: compromised (low birthweight) pigs and starveouts, he says.

Akey is cooperating closely with S&R Resources, which makes and sells Rescue Decks, to focus on saving those pigs and producing more full-value pigs through to market. These compromised pigs will average .5 lb. or more gain/day on milk, and achieve 10 lb. or more in 14-15 days in the deck, according to Cera.

For proper use of the decks, focus on placing only the small, compromised pigs in the decks, not whole litters, to achieve heavier pigs after weaning. Maximum recommendation for the Rescue Decks is 12 pigs, he says.

Rescue Decks are plastic-molded, enclosed structures that are bolted on a frame between two farrowing crates. It includes two front milk cups, a continuous circulating loop milk line, plastic-coated woven wire flooring and a partial lid that stays partially open or closed depending on air quality. A third cup provides fresh water to the pigs. A heat lamp above the deck features a dimmer switch to adjust the temperature, explains Cera.

The milk replacer made by Akey for the decks is called Nurse-On. Pigs can transition to Akey's preweaned pig feed product, called Pig Creep, as early as 9-10 days of age, providing both wet and dry sources of nutrition while saving the cost of exclusively feeding pigs milk replacer.

Results

Piglet survival rate in company research and producer trials has averaged at least 90%, says Cera. Lowering preweaning mortality by 3% pays for the equipment in less than six months.

Find out more about Rescue Decks by clicking on www.rescuedecks.com. For more on Akey's milk replacer products, click on www.akey.com.

Table 2. Raised Deck Economics for the Pig Palace
Milk cost (annual basis)
Death loss benefit — 3%
Pigs saved/week — 21
Pigs saved/year — 1,092
Value of pigs saved — $42,588.00/1
Overall weight benefit — .5 lb./pig
Value of weight benefit — $9,100/2
Total benefit — $51,688.00
Total cost — $37,777.50
(Excludes capital cost for raised deck systems estimated to be paid for in two years or less)
Net benefit — $13,910.50
1This figure is based on 1,092 pigs multiplied by a formula price of $39 for 20-day-old weaned pigs.
2This value comes from how pigs are priced out of the sow unit. They are priced $.50 higher for every pound of weight over 12 lb. Therefore, Pig Palace is getting an extra $.25/pig for every pig because they weigh a half pound more.

When to Consider Raised Decks

Mike Eisenmenger, DVM, Swine Vet Center, St. Peter, MN, serves as the consulting swine veterinarian for Pig Palace. He advised owner Ron Juergens and swine division general manager Steve Huegerich to install the raised farrowing decks after viewing their successful use in Canada.

Eisenmenger is quick to point out that the decks aren't for everyone, and that management must be committed to make them work.

Two factors should be considered when using raised farrowing decks: the number of pigs born alive and the milking ability of your sow herd. If born alive is 10 or below, there should be adequate teat space; therefore, other management steps may be needed to save pigs.

If the milking ability of your herd is really poor, then pig-saving methods may not be enough. Changing the sow herd may be your best bet.

Eisenmenger stresses the best barometer of whether to use raised farrowing decks is if the total number of liveborn pigs exceeds teat capacity.

Those pigs add value to an operation. “What I generally tell people is that we figure each extra pig they wean is worth $34-35,” he says.

There are a growing number of farms producing high born-alive numbers of pigs, says Eisenmenger.

“We are going to have to be more creative on how to save all of the pigs we produce,” he emphasizes.

“The genetic companies have done a fantastic job of getting born alive and total born to very high levels. Now we've got to figure out ways to save the pigs that we create through total borns. And raised decks might be one way for people to go,” says Eisenmenger.

Triumph Foods Awarded Grant for Illinois Plant

The state of Illinois has awarded almost $16 million in economic development funds for Triumph Foods to build a new, state-of-the-art pork processing plant in East Moline, IL.

“We are always looking for opportunities to attract new companies and new jobs to Illinois,” says Illinois Gov. Rod R. Blagojevich. “Triumph Foods is investing $135 million to build this state-of-the-art facility that will eventually bring 1,000 new jobs to northwest Illinois (by 2010).”

Triumph Foods, a pork processing company based in St. Joseph, MO, plans to start construction in the spring of 2007 on a 620,000-sq.-ft. plant on 116 acres in East Moline, IL. Completion is slated for the first quarter of 2009. The new plant is a pork processing facility only.

“With its large, available workforce, central location and great road and air access, the Quad Cities region is an excellent fit for us and was the best choice for our new, state-of-the-art pork processing plant,” says Rick Hoffman, CEO of Triumph Foods.