By Dr Andrew Tucker, CS Vet
What is Rotavirus?
There are many different types of Rotaviruses affecting various species of animal. Some types of Rotavirus also affect pigs. These viruses are very resistant outside of their hosts, living up to nine months in manure, at 20˚C. This means that they are difficult to rid from the environment and hence are thought to be present in all pig rearing areas.
Rotavirus spreads on farm, from the sow to her litter, directly after farrowing. It then also spreads between litter mates up until they are about 40 days old. The virus enters via the mouth, moves down and colonises the small intestine, where it then does its damage.
How do you know if it’s on your farm?
The virus mainly affects suckling piglets although it can cause less severe weaner house scours. The main clinical sign is profuse yellow diarrhoea. The first signs seen can be vomiting, piglet not eating and reluctance to move. The clinical signs last for four to six days and in this time up to 30% of affected piglets may die.
Clinical signs as well as post mortem findings can point towards a Rotavirus infection but further laboratory testing is needed to confirm the diagnosis. Rotavirus is often part of a mixed infection that causes the scour, so simply confirming its presence does unfortunately not mean that it is the pathogen causing the problem.
How do you treat or prevent it?
When treating, it is crucial to firstly deal with any bacterial or protozoal co-infections. Providing water is very important. Fluid replacement with glucose and electrolyte solution may be of value.
Prevention and control are really focussed on disinfection and hygiene. In severe cases it may be necessary to stimulate maternal immunity by feed-back or vaccination (no registered vaccine currently available in RSA) but the risks of these procedures should first be investigated and considered.
Pig Diseases – D.J. Taylor; Diseases of Swine – Straw, Zimmerman, D’Allaire, Taylor