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Market disruptions have forced swine producers into some unique situations in the past six months, such as slowing down pig growth and increasing stocking densities in barns.

Because of this, vice behaviors in finishing pigs have become a bigger concern for producers.

Vice behaviors such as tail biting, ear biting, ear base sucking, flank nudging/biting and vulva biting are not simple issues to solve. In fact, what causes vice behaviors is a pretty complex question, said Elise Toohill, DVM, with Carthage Veterinary Services during the 30th Annual Swine Health and Production Conference.

“Vice behavior is one of those things that has many root causes. As we continue to get better each day and learn more about what our pigs truly need, we continue to find more root causes,” Toohill said.

What Causes Vice Behaviors?

When pig production moved indoors, the pig’s natural tendency to forage in the dirt was reduced. Toohill said this is one reason pigs might redirect that behavior to nudging feeders, gates or even other pigs.

Another type of behavior that is typically limited to a few animals in the pen is “boss hog” behavior, when an individual is overly aggressive and moves from pig to pig to pig in the pen biting the other pigs. Although this is more common in gestating sows in pen gestation scenarios, she said it can occur in finishing barns.

“More often than not, vice behavior is aggressive behavior that’s an outcome to something that’s lacking in the pig’s environment or something that’s causing a significant amount of stress,” she said. “Rarely is there ever a single cause.”

These stackable stressors compound to create a large problem. This is why farmers may see that an out-of-feed event can trigger these underlying stressors and result in vice behavior problems.

Vice behavior in and of itself is not a disease, she added, but health is a component and pigs can get a disease or infections as a result of a vice behavior.

“Think about when you get a cold – you don’t feel well and it’s speculated that pigs can have similar uneasiness and discomfort that could lead to them exhibiting the aggressive behavior,” Toohill said. “A lot of diseases or infections, particularly viruses, cause indirect impacts to feed and water intake, which can lead to vice behavior.”

Diseases and infections can also occur secondary to trauma. Vice behaviors can create open wounds which could lead to skin infections that start after the vice behavior is initiated or cause local or systemic infections after the biting is started.

The most common pathogens that cause sepsis of skin disorders are circovirus, porcine reproductive and respiratory syndrome (PRRS), influenza, Actinobacillus, Streptoccocus, Escherichia coli, Erysipelothrix, Staphloccocus Hyicus, Sarcoptes scabiei and Demodex phylloides.

How Does the Diet Impact Vice Behaviors?

Some level of deficiency in nutrients could cause vice behavior. However, most producers work with great nutritionists who set up rations that would not result in deficiencies that could cause vice behaviors. But Toohill always asks if the pigs are being fed what they are supposed to be fed.

“There’s a lot of things that can happen from the time they formulate the ration until that ration hits the bin,” she said. “That could cause a deficiency that we don’t think is there.”

In addition, make sure feed intake matches what the nutritionist thinks they are getting fed. If this is off, they may not be consuming enough to get the nutrients that they need. Always evaluate mycotoxins, too, because some mycotoxins cause poor circulatory perfusion and subsequent necrosis that could lead to vice behavior, Toohill added.

“Remember that availability of resources varies by genetic lines,” she said. “Work with your geneticists or genetic company to make sure that you’re meeting the needs of that pig.”

Small out-of-feed events can be just as impactful as the large out-of-feed events because they all add up, Toohill explained. Individual pens might be out of feed versus the whole barn. If you have differences in stocking throughout barn, and your auger runtime is just a little bit too short, you could have an individual pen that’s running out of feed just for a few hours a day multiple times a day.

Pay attention to your pigs’ water supply. Make sure pigs can access a high enough volume of good quality water every time they drink and that you have the minimum needs of floor space.

“Pigs tend to all eat and drink at the same time per day,” Toohill said. “So if you’ve come in to evaluate feed or water availability in the middle of the afternoon on a really hot day when pigs are sleeping, it might look different when you go and evaluate it at night when it’s cool and all the pigs are going to the feed and water at the same time.”

Focus on Prevention

Vice behavior treatments are often unrewarding once an episode begins, she warned. Focus on prevention. Here are three ways to prevent vice behaviors from causing issues in your herd.

1. Create minimum standards for facilities.
2. Ensure you have appropriate stocking plans to distribute resources effectively.
3. Execute basic production protocols of feed, water, air care and comfort daily.

If a problem begins, react immediately by removing any stressor that you can from your pig’s environment. Stressors may include commingling, mixing of pigs, pen design that limits pigs’ ability to get away or get to available resources, humidity, drafts, poor air exchange rate, temperature fluctuation, wet floors and stray voltage.

Some producers have found success when they provide enrichment items such as chains or bowling balls in the pens, she said. Enrichment items provide pigs an outlet to release frustration and anger.

Finally, be on the lookout for problems. Isolate and treat individual pigs that have lesions so you can prevent systemic and local infections from forming.

Vice behaviors are often caused by multiple factors, so Toohill reminded producers that adjusting one factor may not be enough to prevent losses. Consult your veterinarian and nutritionist for help and focus on what you can control in your barn.

Farm Journal’s Pork | Jennifer Shike | September 02

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