title: The avian major histocompatibility complex influences bacterial skeletal disease in broiler breeder chickens.
abstract: This study evaluated bacterial skeletal disease in conjunction with the major histocompatibility complex (MHC) in a genetically pure line of broiler breeder chickens. Chickens from six broiler breeder flocks were examined for skeletal lesions, bacterial pathogens, and MHC genotype. During a 10-week period, eighty-eight, 9- to 21-week-old lame chickens and 34 normal, age-matched controls were selected. Tenosynovitis, arthritis, and femoral or tibiotarsal (or both) osteomyelitis occurred in 86 of 88 (97.7%) lame chickens. Ninety-five bacterial isolates were obtained from 83 of 88 (94.3%) lame birds and 4 of 34 (11.8%) controls. Staphylococcus spp. was isolated from 72.6% of the skeletal lesions, predominantly Staphylococcus aureus (38.9%). MHC B complex genotypes were determined by hemagglutination for 88 lame birds, 34 controls, and 200 randomly selected birds from each of the six flocks (1,200 total). Combined chi-square analysis revealed that the homozygous MHC genotypes B(A4/A4) (chi(2) = 14.54, P = 0.0063) and B(A12/A12) (chi(2) = 42.77, P = 0.0001) were overrepresented in the sample of symptomatic birds compared with random samples from the same flocks. The homozygous A4 and A12 MHC genotypes influenced flock chi-square values more than the corresponding heterozygotes. An MHC B complex influence on bacterial skeletal disease was apparent in this line of broiler breeders.
authors.affiliation: Department of Pathobiology, College of Veterinary Medicine, 166 Greene Hall, Auburn University, Auburn, AL 36849, USA.
authors.forename: K S
authors.initials: KS
authors.lastname: Joiner
authors.forename: F J
authors.initials: FJ
authors.lastname: Hoerr
authors.forename: E
authors.initials: E
authors.lastname: van Santen
authors.forename: S J
authors.initials: SJ
authors.lastname: Ewald
mesh_terms: D000818:Animals; D001847:Bone Diseases / Q000235:genetics / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D002645:Chickens; D005838:Genotype; D006386:Hemagglutination Tests; D006652:Histological Techniques; D008285:Major Histocompatibility Complex / Q000235:genetics*; D011201:Poultry Diseases / Q000235:genetics* / Q000382:microbiology / Q000473:pathology; D013045:Species Specificity; D013203:Staphylococcal Infections / Q000235:genetics / Q000473:pathology / Q000662:veterinary*; D013210:Staphylococcus