Staphylococcus Infection in Broiler Breeders
Staphylococcus aureus (Staph) is a common bacterium found in every poultry house, and yet some focks have problems with infection while others do not. S.a. can remain viable on inanimate objects for months. Infection can have a major impact of the productivity of a breeder flock, and significantly affect fertility. Staphylococcal infection, caused by S. aureus, is a major cause of lameness in breeders. This bacteria can infect any age of breeder, although occurance is most obvious in younger adult breeders.
Staph, a normal part of the poultry house environment, can be an opportunistic pathogen. Stress or injury provides the opportunity this bacteria needs to enter the birds body and cause an infection. Infection is most likely to occur when the immune status of the breeder pullets is compromised, such as at the time of beak trimming or moving.
Stress can cause immunosuppression in the flock, which allows the bacteria to enter the birds body and cause the disease. In normal, low stress situations, the immune system of the bird would be able to fight off potential infection by bacteria entering the body by routes such as the lungs, beaking trimming sites, de-toeing and de-spurring sites and injection sites.
Injury also provides a location for the bacteria to colonise, resulting in a localised infection. Immunosuppression is not necessary for this to occur. General management conditions and equipment maintenance should be carried out to reduce physical injury.
Infection by Staph can occur in the joints, or it can be a generalized (septicemic) infection. The most common problem in broiler breeders is infection of the foot (bumble foot) or the hock (swelling of the joint which is warm to the touch). Infection at either of these sites will lead tolameness of the bird and a decrease in production. If bumble foot occurs in the males, decreased mobility will result in a reduced number of mating attempts and decreased fertility. Decreased mobility in the hen would lead decreased fertility as well, since they would be less willing to leave the area feed and water are located. Production for affected birds would also decrease as they would be less able and willing to compete for feed during the feeding period.
Although there are treatments for Staph infections, prevention is the key to minimizing the economic impact of the disease. Since open injuries are the main route of entry, especially in the case of bumble foot, removal of all sharp edges within the house is essential. If the birds brush by these edges, causing a small abrasion, infection is almost inevitable. Injury can also be caused by excessive physical activity, an example in fierce competition for feed. Since stress increases the susceptibility of birds to this disease, reducing stress is a good approach to preventing it. Move birds as seldom as possible and supply stress relief (eg. Vitamins in the water) to help them deal with events such as moving, beak trimming and vaccination by injection.
Antibiotics can be used in the feed or water, which may clear up the infection, but any damage to the feet and legs of the bird will be permanent. Giving antibiotics in the drinking water for 1 – 2 days prior to and 1 – 2 days following vaccinations and beak trimming (consult with your veterinarian) is also a possibility where staphlococci infection is a major cause of leg problems.
If breeders exhibit a high incidence of staphylococcus infection then at flock depletion, the house must be thoroughly cleaned and disinfected with cresylic acid based disinfectants and then ideally fumigated.
Michael Leslie – Canadian Poultry Consultants Ltd.
S. Leeson and J.D. Summers – Broiler Breeder Production
Date published: 2003-12-01
C. Bowles; (References)
Leeson and Summers and Leslie