What is Rotavirus?
Rotavirus is an infection which damages the intestines of birds, resulting in a yellow watery scour.
Implications of Rotavirus
Dehydration also occurs, and mortality can be as high as 50%; however, it’s usually between 5-20%. If birds recover, they can become stunted and this can lead to uneven batches of poults. There is a link between rotavirus and an increased susceptibility to chilling and other diseases. This viral infection is most often seen in birds between 7 and 10 days old and can come from contamination at the hatchery or from infection on the rearing site. Rotavirus is very infectious and will spread rapidly between chicks. Once it is on site, it is very difficult to shift that season.
There are a few different ‘strains’ of rotavirus and gamebirds are usually affected by group A rotaviruses, but non-group A (atypical) rotavirus infections also occur, such as type D. The virus replicates in the cells of the lining of the gut destroying them in the process, and severely reducing the surface area available for absorption of water and nutrients.
Clinical signs
- Birds are likely to be depressed/inactive
- Passing loose droppings
- Their wings will droop
- Ruffled feathers
- Wet bedding
- They may show signs of emaciation and wasting
- Unevenness
Dehydration, septicaemia and toxaemia may follow rotavirus.
Diagnosing rotavirus
Diagnosis is usually via a postmortem and testing of intestinal contents through an external laboratory.
Treatment and control
There is no specific treatment for viral infections however supportive care and reducing the viral load will minimise the effects of the virus. Fogging of antiviral solutions like Halamid both onto chicks at a low dose and in the hatchery are a key tool.
Electrolytes can be used to counter dehydration (especially worthwhile in the acute stages of infection), and antibiotics may be useful to prevent secondary bacterial infections. However, often there is a poor response from infected birds to antibiotics.
Birds tend to be dull and do not drink and eat and therefore any uptake of medication can be compromised.
There are some proprietary products, such as an egg powder, from chickens that have been vaccinated against type A rotavirus and there is some evidence of its efficacy. A virucidal powder in the drinking water such as Virkon H2O can also aid control.
Good gut bacteria seem to help in outbreaks of disease and the use of probiotics as a chick starter medication can help to establish a good flora and makes the chicks better able to fight disease.
As always bio-security is important as the disease is very easily spread by contaminated personnel and equipment. It is also important not to mix ages of chicks as the older birds can be carrying the disease without many outward signs but be able to pass it on to the susceptible immature younger chicks.
If you have any concerns about the health and welfare of your birds call us on 01392 872932 or email info@stdavids-gamebirds.co.uk
