Discussion of sow mortalities has been a recent hot topic, as losses have increased over the past five years.
Sow mortality can be crippling to a production system, but the production effects of sow death loss can be multiplied as producers may be forced to keep animals that would normally be culled to enable them to hit production numbers. When sow death loss continues to increase, producers become restricted to cull only the most severe animals rather than those that should be culled.
Brad Leuwerke and Henry Johnson, veterinarians with the Swine Vet Center in St. Peter, Minn., say often lameness, feet and legs are a huge driver of sow mortality on farms, and prolapses are also big factors for some farms, but Leuwerke and Johnson say no clear causes of prolapses have been found to date. “There doesn’t appear to be parity association,” Johnson says. “The highest risk timeframe is generally going to be five days pre-farrow to five days post-farrow, that’s when you’re going to catch the majority of the prolapses occur.”
Around this high-risk time for prolapses producers should look for constipation, a bulging perianal area, vulvar swelling and edema, and if the animal appears to be straining with no piglets showing, but Johnson admits that not all sows that end up prolapsing will show these symptoms. A typical profile of a prolapse sow is a highly productive sow, “ones with 18 total born alive, big healthy pigs, that kind of sow is your typical” sow that will suffer prolapse.
As mentioned above, there is no clear-cut reason for the increases in sow prolapse, but rather a potential multifactorial effect of several risk factors such as feed, mycotoxins, hormonal pressure, mineral imbalance and increased abdominal pressure from larger litters of increased birthweight pigs.
Leuwerke and fellow SVC veterinarian Laura Bruner recently summarized the cost of prolapses based on record analysis from a 2,500-sow farm of an SVC client. This analysis showed a cost of roughly $34 per inventoried sow or $850 per prolapsed sow.
Just as there is no main reason for prolapses, there also is not a silver bullet for intervention, but Johnson encourages producers to be willing to try multiple interventions on their farm, such as top-dressing a laxative plus a cal/phos supplement, or maybe a transition diet.
Leuwerke says lameness, feet and legs are still about 10 to 15% of a herd’s mortality base of the last five years. “So that’s still a big deal on farms. And it’s not only mortality from lameness, but we also know that those that get pregnant and farrow out have lower production and eventually will be culled out.”
It’s clearly been established that sow death losses have been on the rise, and for a variety of reasons, but what can be done. Leuwerke and Johnson cannot stress enough the importance of “getting the basics right.”
In that vein, the Swine Vet Center has established this list of 10 “non-negotiables” when it comes to sow care.
1. Make sow death loss a priority to farm staff
“This is just as important as pre-weaning mortality or any other production targets a farm sets,” Johnson says. Stressing to farm staff the specific steps to prioritize sow death loss is imperative to get the entire team on board of its importance. Johnson stresses that even one or two animals can be the difference in making the target for the week.
He says the cost of losing a sow is felt throughout the production chain, “the cost of replacing that productivity in the form of another gilt, and you also lose out on opportunity costs and cull value.”
Losing sows can cause a chain-reaction, or domino effect, by “tend to keeping lower quality breeding stock on your farm and replacing that production with keeping a larger pool of lower-producing animals and you can get in a downward spiral where you have to make targets, and to make those targets you end up keeping an animal that you would normally cull.”
Anecdotally producers have been sharing concerns about the rise in sow mortalities, but are those perceptions realized? According to data from the 830,000-sow database of SVC, sow death loss in 2013 was at about 8.5%, as where today that death loss comes in at about 11%. These percentages represent both death loss and euthanizations of sows.
2. Get every animal up, every day
High-risk animals get at least two daily health observations. Make a list every day of problem/trouble animals and make sure they get a follow-up health check or treatment that day, not tomorrow.
How much is enough time to spend with each sow? Observation time of 10 seconds per sow does not sound like much, but that adds up quickly when multiplied by a large number of sows. That’s over two-and-a-half hours spent just observing 1,000 sows. “On a larger farm, that’s almost a full-time employee plus just to make observations, treatments and re-observe the next day to make sure the treatment that you put in place has had some effect,” says Leuwerke.
3. Implement a gilt selection program
“Make sure you’re bringing in the highest quality breeding stock as possible onto your farm,” Johnson says.
Gilt selection, and the gilts themselves, have changed considerably in recent years. “You look at the gilts of today compared to even five, 10 years ago, she certainly is more lean, a lot less body fat and they grow faster,” Leuwerke says. “I’m not saying that drives, or is directly related to durability, but it does seem like when we’re talking about metabolic bone diseases, bone growth and bone strength that that faster growing gilt that if not managed correctly is more likely to become a lame animal and a future mortality.”
High herd health is a goal of every producer and the replacement gilts should be no different. Sourcing gilts with high health status is important, but Leuwerke says it is imperative to acclimate the incoming gilts to the production farm that they will call home for their productive life. “Gilts that are brought into a farm at a mature stage, or even the growing phase, they do have a lot of bugs that they need to get acclimated to,” he says. “Some of those bugs, the bacterial ones certainly cause dramatic arthritis and that is damage that we might not see that first parity and second parity, but eventually can catch up to them and lead to lameness and sows that we end up euthanizing or dying from joint infections.”
As farms move away from the use of antibiotics, Leuwerke says that may open opportunities for bacterial pathogens to move in and cause arthritis and joint infections and take over that you may not see in the growing gilt.
Today’s faster growing, leaner gilts also comes with nutritional limitations. “with nutritional needs that we probably haven’t fully understood what those are,” Leuwerke says. “we probably don’t feed the gilt right for its growth potential and in herds where we don’t have the right number of gilt developer diets, or due to facilities we just can’t feed that gilt right, or after that gilt enters the sow farm we limit feed her unknowingly or intentionally we limit her growth. … that gilt is still growing at that time, so it does lead to structure issues or bone strength issues that catch up with that gilt later down the road as that gilt is a later parity sow.”
Leuwerke questions the gilt selection criteria that farms have in place, feeling the “art” of gilt selection has been lost. “What are your criteria for entering gilts into your farm?” he asks. “Is it just the ones that can walk come in, or do you have a method of evaluating feet and legs and structure as we’re selecting gilts, because that is huge in detecting issues that might arise later.”
The move to pen gestation has also contributed to an increase in lameness issues, but Leuwerke says proper management can reduce lameness in any type of production model. Part of that management is that producers closely monitor the gilts being introduced into a gestation pen, to make sure that lame animals are not moved into a group pen, to only have the issue exacerbated. “We need to have space available that you can pull lame animals out, and even have space for lame animals to gestate,” he says.
4. Ensure every animal has access to fresh food and water
Leuwerke says feed intake is one of the only indicators of how that sow is feeling day-to-day. “Today’s facilities allow producers to monitor each sow’s feed intake, and be able to provide fresh feed, and we should have the abilities to provide ad lib feeding to those sows that less than ideal body condition. … so it gets back to the basics: did she eat today, and if she didn’t what’s the treatment plan in place to address that and then how do we reevaluate that to see if we had an effect.”
The same goes for water, even though the importance is often overlooked. “Hydration is a big deal for overall sow health,” he says. “Water intake leads to feed intake.”
Gilts being moved into a farrowing crate may need to be shown the location and use of the nipple water, as this may be the first time that her water source is located above her head, again stressing the importance of basic husbandry practices.
5. Post sows as often as possible
Someone on your farm’s staff should be accustomed and comfortable with doing post-mortem inspections on a dead sow. Posting sows can be discouraging because sometimes we don’t determine the cause of death. That doesn’t mean it’s not valuable to do this. Post-mortem exam doesn’t have to be perfect. Leuwerke suggests developing a checklist of what to look at for abnormalities:
If something doesn’t look right, alert your veterinarian. Keep in mind that a single post-mortem finding doesn’t necessarily represent an ongoing issue. For that reason it is important to post multiple sows when necessary to determine if there is a health trend, or just an anomaly. Not only do post-mortem exams seek to find answers to a sow’s death, they are also a good learning opportunity for the farm staff to gain information on pigs’ health.
“We really are blind unless we start opening up some sows and understanding why we are seeing some deads,” Leuwerke says. “As you start opening up some sows, and taking pictures and sending them to your veterinarian, and you can start to see some commonalties.”
6. Timely treatment of sick animals
It is best to treat the animal immediately when symptoms of illness first are observed. Putting it off until later in the day may be too late. Proper documentation of treatment and follow-up reevaluation are important to get the sow on the road to recovery.
While the daily observation of sows is imperative and just makes good herdsmanship sense, Leuwerke and Johnson realize that employees are tasked with completing many different jobs each day. “It’s easy to say ‘every sow every day and everything will be better,’ but that may not be the case,” Leuwerke says, “but what we really want to look at, are there subsets of sows in the herd that are at higher risk of mortality compared to others?”
Data show that the highest risk periods for mortality of sows are the last couple weeks of gestation and the first week to 10 days after farrowing. This provides producers a specific timeframe to place extra emphasis on early disease identification and treatment.
7. Provide supplemental care when needed
“This is more than just looking at antibiotics,” Johnson says. If you notice that your sows are developing shoulder sores or are showing lameness, providing a mat for their pens or stalls may alleviate issues. If a crate floor is slippery, providing the sow with mats with holes can help prevent them from splaying and injuring themselves.
Leuwerke says sows are good at guarding that pain or inflammation that’s going on, “so that by the time that they are a noticeable lame animal there is already a lot of damage being done.” Once lameness is noticed, antibiotics may not be the answer due to the difficulty of getting that into the joint, and “the infectious part may be out of the joint already, so there may not be a whole lot of benefit there.” Though there may not be a lot of anti-inflammatory options available, that may be a solution to relieve some of the pain to benefit the animal.
Gilts and sows that have been identified as lame need to receive special care, as well as reassessing their care and hopeful progress over multiple days.
One facet of sow, gilt care that Leuwerke says producers as a rule do a poor job of is paying attention to their feet, and the proper trimming of the pig’s claws. Proper hoof trimming can alleviate a lot of foot and leg issues down the road.
8. Rectal temperature sows post-farrow
Another tool that Leuwerke admits that doesn’t get used near enough on farms is the regular taking of rectal temperatures of sows soon after they have farrowed. “It’s great to say, yup we’ve got a fever so there’s some infection or something going on, and then determine what intervention should be in place.”
Intervention with nonsteroidal anti-inflammatory drugs or antibiotics can help the fever subside, but don’t just treat and forget. It is important to perform a second health check later in the day to determine the success of the intervention, and if further treatments are needed. “Get her up and walk her, whatever you’re comfortable with on your farm,” Johnson says, will also help.
New PRRS strains, as well as many of the other pathogens that can infect herds, bring with them higher fevers that can lead to mortality if not properly treated in time.
9. Get body condition right
“It’s really important on your farm to implement a program that we’re going to check sows at this timeframe, and then we’re going to recheck the sows after we adjust feeders and make sure we get sows where they need to be body condition wise,” Johnson says.
Under-conditioned sows run an increased risk for lameness, and if that problem persists they may become downers, possibly resulting in euthanization. “A thin sow, or an under-conditioned sow, we need to do everything that we can to bring that animal back into condition or it’s going to be a higher mortality for the farm,” Leuwerke says. Putting under-conditioned sows on a self-feeder providing that animal to be on full feed or ad lib feed at all times to get that condition right, “because if we don’t that sow will become a mortality.”
Body conditioning can be quite subjective so Leuwerke suggests using tools such as a caliper to make sure the body condition is consistently measured and accounted for on farms. “Having a conditioning plan in place, whether it’s at breeding, 30-day, 60-day or pre-farrow, or whatever works on your farm, just make sure it’s done every week, and make sure that much like treatment we have a plan in place for those sows that become thin, or are over-conditioned, what things can we do to get them back into condition in the shortest amount of time.”
10. Stabilize herd health
“Probably the most important on our list, but also the hardest to do sometimes,” Johnson says, “but a bad PRRS break can double your mortalities for the year, so it’s essential.”
Producers can do all things possible to keep their herds healthy, but there are a number of bacterial and viral infections that lead to mortality in adult animals, and “and the big one continues to be PRRS, and we continue to be humbled by PRRS this time of year, and it seems like new strains have an ability to cause higher fever and more sick animals than they have in the past,” Leuwerke says. “We have seen farms that can double their mortalities in just a manner of weeks due to this higher fever of these new strains.”
Multiple control strategies exist to combat PRRS in your herd — elimination, vaccine, serum exposure or gilt acclimation, “but the big one to me is doing everything that we can from a biosecurity standpoint and a testing standpoint to limit the introduction of the virus, especially the strains of today that seem to cause that dramatic fever event and mortality,” Leuwerke says. “That seems like it gets out of control before we can get ahead of it.”
In addition to PRRS, producers also need to be alert for circovirus, influenza, ileitis, mycoplasma, erysipelas and the suises: Haemophilus parasuis, Actinobacillus suis and Streptococcus suis.
Stress the basics
Producers who are present, observant and attentive to the needs of their producing females will be ahead in the long run at reducing sow mortalities, and as Leuwerke and Johnson, stress getting back to the basics of animal care. Some opportunities to reduce mortalities exist when producers assist the sows farrowing and document the completion of the farrowing.
Don’t forget about the sow once she is done farrowing. “Be sure to get them up to eat and drink post-farrowing,” Leuwerke says. “I think in general with the automated feeding systems, maybe we don’t do a good enough job of making sure they are eating after farrowing.”
Johnson and Leuwerke led a session on sow mortality during the Minnesota Pork Congress in January.