Coccidiosis Remains Hot Weather Threat in Young Pigs

In our practice, piglet diarrhea due to coccidiosis, an intracellular protozoan parasite, is typically seen in the hot summer months. This corresponds with the caseload at Iowa State University’s Veterinary Diagnostic Laboratory.

During its intricate life cycle, oocysts are found in the environment, and contain a thick outer coating very difficult to destroy with disinfectants. These oocysts are ingested by piglets, which leads to the release of sporozoites. The sporozoite enters cells lining the intestinal wall and cause destruction and diarrhea as they continue their life cycle.

Through the years, multiple treatments and preventions have been tried with various levels of success. Involve your veterinarian in diagnosing and treating neonatal diarrhea.

Case Study No. 1

During a monthly herd visit to a 1,200-sow weaner pig farm, I noticed the older pigs (18-21 days) ready for shipment, were not as “thrifty” in their typical appearance.

It was a hot, humid August afternoon. Drippers were running continuously on the sows, leading to wet mats and wet-greasy pigs. The owner had not noticed the yellow pasty-to-watery stools in the corners of the crate. The pigs had long hair coats and appeared slightly gaunt and dehydrated.

Necropsy findings demonstrated a white “cottage cheese” appearance in the small intestine. The lining of the intestine was severely damaged. Coccidiosis was suspected and confirmed at the diagnostic lab.

The following therapies were quickly established:

• Mats were removed from the crates at seven days postfarrowing so moisture was not retained. Mats were soaked in bleach and air dried in the sun.
• Drippers were set to turn on for short periods of time (3-5 minutes) and off for longer periods (20-30 minutes) to improve evaporative cooling and keep piglets drier.
• Detergent was added to the cleaning and disinfection procedures. The detergent helped remove the biofilm found on crates and equipment and reduced the level of oocysts in the environment ingested by the piglets.
• Feedback of piglet feces to sows prefarrowing was halted during the summer months to reduce shedding from the sow into the environment.
• Drying powder was applied to piglets, mats, and sow udders twice daily for the first seven days postfarrowing. Any scouring litters were powdered 2-3 times/day.

Symptoms improved as the protocols were implemented, and disappeared with cooler weather in October.

Case Study No. 2

A producer selling antibiotic-free pork called complaining of diarrhea in 5-7 day-old pigs. Some sows were farrowed on pasture in metal huts with no floors. Other sows were farrowed in wood huts with wood floors. Mortality was not high, but nearly all litters had yellow, pasty or yellow, watery diarrhea. Antibiotic treatment was not an option.

Diagnostic results yielded coccidiosis as well as rotavirus. Steps included:

• Rotavirus was handled through the implementation of rotavirus vaccine given prefarrowing to sows and gilts.
• Wooden houses with wooden floors were cleaned with detergent and disinfected. A wood “water sealant” was then applied to help seal up the oocysts in the wood. Houses were also powdered with lime.
• Sow huts on pasture were moved so that sows would farrow on cleaner soil. Old bedding was burned and the huts were doused with lime.
• Prescription antiprotozoal paste was given to piglets at first processing.

Clinical signs began to improve and no antibiotics were utilized.

Case Study No. 3

A producer who purchases weaner pigs called complaining of diarrhea, “rail-back” and poor-doing pigs delivered to his nursery. Necropsy lesions were consistent with coccidiosis and confirmed at the diagnostic lab.

An acidifying agent and antibiotic for secondary E.coli bacteria were placed in the water for seven days. The majority of pigs rebounded nicely.

The sow farm was notified, and preventative protocols for coccidiosis were implemented.

Summary
A recent study from Greece revealed other management practices to help reduce coccidiosis:

• Thorough cleaning of farrowing rooms and running them all-in, all-out.
• Eliminate crossfostering after 1 day of age.
• Plastic flooring showed less incidence of coccidiosis than metal flooring.
• Caretakers should avoid walking in farrowing pens.
• Prescription antiprotozoal agents can help reduce coccidiosis.