Managing Mycoplasma’s persistence in finishing

A dry cough heard in a finishing unit usually indicates Mycoplasma hyopneumoniae (M. hyo) is causing respiratory distress and reducing growth in pigs almost ready for market.

“We’ve been seeing M. hyo in finishing where it pops up in mid- to late-finishers,” reported Bryant Chapman, DVM, Four Star Veterinary Service (FSVS). “It decreases feed intake and potentially causes mortality, especially if it has a secondary disease with it as well.”

Working from the FSVS clinic in Chickasaw, Ohio, Chapman helps clients reduce the effects M. hyo can exert on a farm if left unchecked. The cost of finishing pigs infected with M. hyo is estimated at $3 to $5 per head more than pigs without the disease.

Immediate response

“Mycoplasma is a slow-moving bug and is slow to show itself, which is why we see it in finishing,” he explained. “Clients will call and say ‘I have healthy-looking finishing pigs, but they have this dry, non-productive cough.’

“Depending on when the hogs will be marketed, we rely on antibiotics. Feed-grade and water-grade medications given over a period of time do fairly well to decrease the symptoms at the finishing level. And we do follow-up with injectables on a few animals needing it.”

Because M. hyo is a respiratory pathogen, dusty conditions and poor ventilation will exacerbate the symptoms. It also appears more in the winter when buildings are closed up.

Seeking the source

“Some farms we work with on finishing, the clinical signs show up at the end stage when they get compounding factors like porcine reproductive and respiratory syndrome (PRRS) or the flu and we find M. hyo via testing,” he added.

To test M. hyo in finishing, Chapman recommends using lung tissue from freshly euthanized pigs rather than oral fluids from live pigs, which is a less sensitive test.

Typically, the source for an M. hyo outbreak is at the sow farm. Sometimes, the outbreak in finishing is the first indication that a sow unit may be infected with M. hyo, especially if the sow unit went through an elimination for the disease. Tracheal or laryngeal swabs for testing verify the disease outbreak.

Depending on the severity of the outbreak and the herd’s health status, sow farms may work out a control program with their veterinarian to use vaccinations and exposures. Or they may decide to undergo an elimination of M. hyo.

Pros, cons of elimination

“Many farms choosing to go through an M. hyo elimination have either been exposed to or associated with PRRS,” Chapman said. “If they are going to do a PRRS elimination, they will just go that extra length of time to eliminate mycoplasma.”

Eliminating two diseases at once is a positive, but the time needed to eliminate both is 8 to 9 months.

A successful elimination is also helped by the farm setup. “If you have the availability and resources to stock enough females for a closure, or you can have off-site breeding facilities for a closure, it might be feasible,” he explained. “But if you have to completely shut down females for 8 or 9 months without any prep for a pause in production, that would be pretty painful for a farm.”

Hog farms have used different methods to eliminate M. hyo and other disease from their herds. Generally, all methods are costly, and the level of success is 50% to 80%, Chapman said.

Some farms have been able to keep M. hyo out of the system. He works with a few farms that are negative and have not found it in their finishers.

In the end, producers dealing with M. hyo will need to decide based on a cost/benefit analysis what path will be best to handle the pathogen in their own unit, he added.

 

Check with your Four Star veterinarian to determine the best steps forward following a mycoplasma outbreak on your farm.

Early intervention minimizes health issues caused by calf scours

Early identification and treatment of calf scours is the best way to prevent serious health issues in newborn calves, according to Trey Gellert, DVM, Four Star Veterinary Service in Chickasaw, Ohio.

Scours are the leading cause of death for calves during their first 35 days of life. The major causes include bacteria (Clostridium, Escherichia coli and Salmonella), viruses (rotavirus and coronavirus) and parasites (Cryptosporidium parva, coccidiosis and Giardia).

“It’s not necessarily the scours we worry about but the symptoms the scours can cause,” Gellert said. “Calves possess the capacity to fight most types of scours. It’s the dehydration due to scours that will kill a calf.”

He recommends several management tips to help keep calves healthy.

Identify early

“The focus during the first 2 weeks of life should be looking for signs of dehydration because you expect calves to be scouring,” he said. “If I expect it, then I’m more likely to intervene earlier.”

Caregivers should check calves daily, looking at manure and watching for slow or lethargic calves. “If a calf is just a little slower than usual, that’s the calf you need to pay attention to,” Gellert explained. “It might not be scours, but it’s important to figure out why that calf is a little off.”

He recommends doing a skin-pinch test on the calf’s neck to see if the animal is dehydrated. If the skin does not snap back quickly, the calf is dehydrated and needs rehydration. Other signs of dehydration are a dry nose or gums.

Sunken eyes also indicate a problem. “The more sunken the eyes, the more dehydrated the animal will be,” he said. “This is a later stage of dehydration and a lot of people will notice it. The calf also may be lying down and very dull because it doesn’t have enough energy to get up. We have to do a lot of fluid replacement to get these calves back to a correct status.”

Rehydration treatments

Many different oral electrolyte products are available to rehydrate calves. Gellert suggests working with a veterinarian to find the correct electrolyte balance to help the calf absorb and hold water. These compounds also have alkalizing agents to buffer acidosis that occurs with scours.

The replacement fluids are administered orally, subcutaneously or intravenously. Oral fluids are most easily given but work the slowest of the three methods. Fluids given subcutaneously under the skin work faster than oral, but the fluid must still be absorbed.

“I like to use a combination of oral and subcutaneous in cases that are severe enough to call for more than just oral rehydration,” Gellert said. “This method will give you your best success.”

Intravenous fluids given directly into the blood stream work rapidly but are generally given by a veterinarian.

Some cases of scours like bloody scours will require more than rehydration. Gellert recommends bringing in a fecal swab or feces to be tested to help determine the causative agent. Depending on the results, an appropriate treatment plan will be determined.

Preventing scours

A pre-calving or pre-freshening vaccination protocol will help protect newborn calves against major causes of scours like E. coli, rotavirus and coronavirus.

“Cow-calf herds should look for good colostrum protection,” Gellert said. “It will give systemic immunity and local gut immunity against early calf scours.”

Oral products are also available for the newborn calf to help protect against bacterial causes of scours. These need to be administered in the first 24 hours after birth to be effective.

Basic biosecurity also helps reduce scours. Gellert recommends making sure calves are born in clean, dry environments to decrease disease pressure from scour-causing pathogens.

“For dairy beef calves, make sure everything is clean and disinfected including nipples, bottles and pens,” Gellert added. “Simple things like that will help decrease disease pressure.”

Other basic biosecurity safeguards apply, like disinfecting a nipple bottle when shared between calves. Boots can pick up scours, and the caregiver will walk the pathogen through the barn. Make sure caregivers wear clean clothing and boots.

“A good-quality milk replacer also gives the calf the energy it needs to fight scours so the calf can mount its own immunity to these diseases,” he added.