Avian tibial dyschondroplasia: the interaction of genetic selection and dietary 1,25-dihydroxycholecalciferol.

Abstract

The effects of dietary 1,25-dihydroxycholecalciferol on the incidence and severity of tibial dyschondroplasia (TD) were assessed in broiler fowl selected for TD (high-TD line) and against TD (low-TD line). Assessment was by examination with a portable Lixiscope to identify lesions in live birds, gross pathology and histopathology. Eighty broilers in four groups of 20 were examined. When fed on standard diets the low-TD line had a 15% incidence whereas the high-TD line had a 63% incidence. The chicks in the high-TD line, when fed on a diet supplemented with 5 mug or with 10 mug 1,25-dihydroxycholecalciferol/kg diet, showed a marked reduction in the incidence of TD, to 21% and 0% respectively. The growth plate in the proximal tibiotarsi of the high-TD line showed accumulations of transitional chondrocytes, supporting the hypothesis that a failure of chondrocyte differentiation is the cause of dyschondroplasia. This hypothesis is further supported by studies which indicate 1,25-dihydroxycholecalciferol has a major role in chondrocyte differentiation.

• Authors: B H Thorp, B Ducro, C C Whitehead, C Farquharson, P Sorensen
• Journal: Avian pathology : journal of the W.V.P.A (Avian Pathol) Vol. 22 Issue 2 Pg. 311-24 (Jun 1993) ISSN: 0307-9457 [Print] England
• PMID: 18671020 (Publication Type: Journal Article)