Enteric diseases of major impact in domestic hens

Infectious diseases are one of a number of factors that can affect flock performance. Modern industry practices such as strict hatchery hygiene programs widespread vaccinations use of feed additives and biosecurity precautions have evolved to provide a defense in most cases against serious losses caused by these diseases. However poultry producers must remain on guard against outbreaks of infectious diseases including colibacillosis coccidiosis and salmonellosis among the major enteric diseases of domestic poultry. Colibacillosis and salmonellosis can be transmitted from the hatchery to the facilities where the animals are raised because these agents are inside the egg and the chick is already infected when it is born (vertical transmission) as well as horizontally being the oral route the most frequent.