Rotavirus severity increases in the presence of other pathogens.
Rotavirus type C is currently being diagnosed in multiple diarrhea outbreaks of neonatal and postweaning pigs. Severity of the diarrhea can be moderate to high, but clinical signs typically consist of watery, loose yellow stools lasting for several days, with no response to common antibiotic therapies.
Death loss is not high, although morbidity may be. Mortality is greater when other disease agents are found with Rotavirus type C.
Case Study No. 1
The manager of a 2,500-sow, weaner pig facility dropped off fecal swabs and tissues from 3- to 5-day-old piglets with diarrhea. Necropsy samples were confirmed by an outside laboratory as Clostridium type A + Beta 2 Toxin and Rotavirus type C.
Clinically, 10 to 15% of recent farrowings exhibited watery-to-pasty-yellow diarrhea. Response to our standard clostridium treatments was ineffective. Feedback procedures containing feces and intestines from scouring piglets were reviewed and reimplemented to sows at six, five and four weeks prefarrowing, and to gilts in isolation/acclimation. Five to 10 samples were placed in a 5-gal. bucket of cool water to make a slurry that is fed back at a rate of 1 pint per sow. This process is repeated several times to maximize colostral immunity and help control rotavirus and other pathogens.
After feedback was reinstituted, new farrowings exhibited fewer scours and those with clinical signs responded to our clostridium control treatments.
Case Study No. 2
While visiting a 600-sow, farrow-to-finish operation, multiple pasty stools were noted in farrowing, along with pigs having a “caramel coated” appearance and rough hair coats. When entering the farrowing rooms, there was a distinct odor and many litters had pigs piling on top of sows, even though heat pads and heat lamps were provided.
Due to summer temperatures, drippers were running and fans were ramped up. The flooring remained wet due to the drippers and high humidity and drafts also affected crates near the inlets.
Diagnostic samples revealed E.coli, Clostridium type A and rotavirus. The herd was using a commercial vaccine containing Rotavirus type A, E. coli and Clostridium type C, at five and two weeks, prefarrowing.
These changes were made:
1. Ventilation adjustments and temporary hovers reduced drafts on the piglets. Dripper settings were adjusted to allow the sows and flooring to remain completely dry in between water administration.
2. Crossfostering of piglets with diarrhea was not allowed.
3. New sets of gloves were required when processing each litter. Employees were advised not to step into the crates when catching piglets. Scraping fecal material behind sows was stepped up for seven days postfarrowing.
4. The aggressive use of a drying agent was implemented at birth and in litters with diarrhea.
5. Feedback procedures were reviewed and implemented.
6. More detailed plans to split suckle and insure all piglets suckle colostrum were implemented.
This multi-pronged management approach reduced Rotavirus type C and diarrhea almost immediately.
Case Study No. 3
A 4,000-head nursery struggled with diarrhea 5-10 days postweaning. From previous culturing, we knew F4 E.coli (K88) was present. The bacterium was resistant to nearly all antibiotics tested and treatments were becoming less effective. Mortality had risen from 2% to 4.5%.
A visit to the site revealed gaunt and fall-behind pigs with severe diarrhea. Necropsies demonstrated a variety of different lesions, including Hemolytic E.coli. Final diagnostics revealed coccidiosis, Rotavirus type C and Hemolytic E. coli.
Coccidiosis issues were addressed via sanitation in the farrowing rooms. Feedback to sows prefarrowing was implemented to reduce Rotavirus type C. An acidifying agent with prebiotics was added to the water, postweaning, for five days. A drying agent was applied to the rooms prior to pig arrival and once weekly for the first two weeks postweaning.
Mortality and morbidity returned to normal levels in this nursery flow in about 4-6 weeks.
Rotavirus type C has certainly been getting more attention, although in our practice, it has always been found in the presence of other more pathogenic organisms. Appropriate management techniques and good feedback procedures in the sow herd have helped.
If you notice diarrhea in farrowing or nursery age pigs, consult with your veterinarian for appropriate diagnosis and treatment.