Rotavirus infection

Rotavirus infections present clinically as diarrhea in nursing piglets or in the first 2 weeks after weaning

Alternative names: Rotavirus, rotavirosis

The virus is seen globally throughout swine populations. Four different serotypes (A, B, C and D) affect pigs. Usually, diagnoses focus only on rotavirus serotype A (due to the difficulty to culture the rest of the serotypes). However, there is a PCR test available that can classify all the serotypes. Infections in which two serotypes are involved are frequent. Rotavirus is present on most farms with almost a 100% seroconversion in the adult population. Another epidemiological feature is its persistence outside the pig, where it is resistant to environmental changes and to several disinfectants. Exposure to the virus does not necessarily indicate disease. It is estimated that only 10 to 15% of diarrhea in pigs is caused primarily by a rotavirus infection. 

Sows

• Transient or subclinical diarrhea.

Nursing piglets

• Severe, watery diarrhea in young animals.
• Villi atrophy is a frequent characteristic together with dehydration and malabsorption.
• Diarrhea can persist 3 to 4 days.
• Sunken abdomen.
• Sunken eyes due to dehydration.
• Wet skin around the anus.

Wean pigs and growers

• Variable diarrhea. The disease becomes less significant as pigs grow older. However, if pathogenic strains of E. coli are present, a severe disease with mortality can occur.
• Dehydration.
• Diarrhea persists 3 to 4 days.
• Sunken eyes due to dehydration.

• Poor pen hygiene.
• Continuous use of pens. Adopting an all-in/all-out system is recommended.
• Pig movement.
• Temperature fluctuations.
• Contaminated boots and clothes. 

As with any diarrhea problem in pigs 10 to 14 days old, it is important to make sure - through histological changes and PCR - that rotavirus is the main factor causing the diarrhea. Soak a pH indicator strip in a sample of diarrhea; if the strip turns blue it is a diarrhea caused by E. coli, if the strip turns red it is caused by a viral infection.

• There is no specific treatment.
• Give antibiotics- injected, orally, or in the drinking water to control secondary infections such as E. coli.
• Administrate dextrose/glycine (electrolytes) to avoid dehydration.
• Supply dry, warm, and comfortable resting areas.
• Vaccinating gestating sows 5 to 3 weeks before farrowing can be helpful.
• Sow vaccination is recommended to control diarrhea caused by E. coli, Clostidium, transmissible gastroenteritis, or porcine epidemic diarrhea.