Nature and cause of bilateral ocular dermoids in Hereford cattle

Nature and cause of bilateral ocular dermoids were investigated by field studies, pedigree analysis, clinical examination, light microscopy, scanning electron microscopy, and transmission electron microscopy. It was determined that ocular dermoids in Hereford cattle are a genetically transmitted defect; characteristics of autosomal recessive and polygenic inheritance were observed. Calves typically were affected bilaterally with multiple, connected ocular growths that clinically, histologically, and ultrastructurally mimicked normal haired skin. Sites most commonly involved included ventro-lateral limbus, third eyelid, medial canthus, eyelid and conjunctiva. Centro-corneal and anterior segmental dermoids also were observed.     

Chlamydial infection and perinatal mortality in a swine herd

Chlamydia psittaci was believed responsible for an episode of high perinatal death loss in a swine herd in which 8.5 pigs per litter normally were weaned. In this episode, 18 sows produced 186 pigs, with 50 survivors. Chlamydia was found in tissue samples, and other bacterial or viral pathogens could not be identified. Chlamydia was diagnosed by isolation (ELISA), histologic examination using immunoperoxidase staining techniques, and electron microscopy. Previously, C psittaci has not been considered in the differential diagnosis of swine perinatal mortality.