Does Egg Drop Syndrome exist in Mauritius?

Does Egg Drop Syndrome exist in Mauritius?

Egg Drop Syndrome (EDS) is a viral disease of poultry , affecting poultry and characterised by a sudden drop in egg production, abnormal eggs  (thin and soft shelled, discoloured) while the birds look otherwise healthy.

EDS is believed to occur worldwide although it has never been conclusively demonstrated in certain countries which include Mauritius.

Poultry breeders in Mauritius very often complain about drop in egg production in their laying flocks and claim that “treatments” seldom work. While most of them complain about 20-30% drop in production, some concede that laying resumes by itself after a few weeks. This is not in itself diagnostic of EDS as such signs are seen in other poultry diseases but it does point out that EDS may actually exist in Mauritius.

There is no official documentation supporting the presence of EDS virus in Mauritius although there seems to be an abundance of circumstantial evidence pointing to its existence.

The disease can be easily diagnosed using modern tests including PCR and viral isolation. In 1986, I was gifted some EDS antigens by the University of Georgia, USA in the context of my research as a Senior Fulbright Scholarship to enable me to conduct some diagnostic tests in Mauritius. Haemagglutination Inhibition tests carried out at the then Animal Health laboratory of the Ministry of Agriculture, conclusively demonstrated the presence of EDS infection in laying flocks in the island. However, the integrity of the antigen supposed to be preserved at -20 degrees could have been compromised during the air travel and hence the non publication of the results.

I am not personally aware of any further attempt to elucidate the presence of the virus in Mauritius. The disease has thus never been reported to the World Organisation for Animal Health (previously the OIE) or to the Food and Agriculture Organisation of the United Nations (FAO).

EDS is largely preventable by vaccination and many laying and breeding farms in Mauritius regularly vaccinate their flocks using the vaccine singly or in combination with other vaccines.

For all intents and purposes, it can safely be assumed that EDS virus exists in Mauritius and could be causing serious economic losses in poultry. Vaccination applied to layers and breeders a couple of weeks prior to lay can easily control the disease. Improved farm biosecurity including proper farm disinfection undoubtedly assists in the control programme.

Dr Dewan Sibartie