Emaciation and Sporadic Mortality in Older Laying Hens Caused by Intussusception of the Proventriculus.

Laying hens ( = 2267) ranging in age from 2 to 4 yr in a study evaluating ovarian cancer prevention were necropsied. Those that died or were culled during the 2-yr study ( = 1591) were necropsied weekly to determine the most probable cause of death or culling and cancer status. Hens surviving until the end of the study ( = 676) were euthanized and necropsied.

Avian Encephalomyelitis in Layer Pullets Associated with Vaccination.

Avian encephalomyelitis (AE) was diagnosed in three flocks of leghorn layer pullets following AE vaccination. Ages of the birds were 11, 12, and 14 wk. The submissions came from three different companies located in two geographic areas of the Central Valley of California.

A persistent outbreak of ulcerative enteritis in bobwhite quail (Colinus virginianus).

Ulcerative enteritis is a disease that typically responds well to medication. An outbreak of ulcerative enteritis that was persistent and unresponsive to treatment is described. The outbreak started in semimature birds and progressively spread to younger birds.

Strain persistence and fluctuation of multiple-antibiotic resistant Campylobacter coli colonizing turkeys over successive production cycles.

The dynamics of colonization of turkeys by thermophilic campylobacters that are resistant to multiple antibiotics is poorly understood. In this study, we monitored cecal colonization of turkeys by Campylobacter over three successive production cycles at the same farm. Campylobacter isolated from the ceca was predominantly C.

Campylobacter colonization of sibling turkey flocks reared under different management conditions.

Uncertainty exists concerning the key factors contributing to Campylobacter colonization of poultry, especially the possible role of vertical transmission from breeder hens to young birds. A longitudinal study of Campylobacter colonization was performed in two sibling pairs of turkey flocks (four flocks total). Each pair of sibling flocks shared breeder hen populations and was obtained from the same hatchery.