مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

This study was designed to determine the culling rates of 23 Holstein dairy herds (with an average size of 180 cows per herd) in Neyshabur area in northeastern Iran over a period of three years from 2001 to 2003. The average annual culling rate was 13.1%, (98.5% involuntary and 1.5% voluntary). Of the total disposals (1612 cows), 53.48% were culled by the end of five years of age. Poor fertility was the most important reason for culling (34.9% of disposals), followed by digestive disorders (12.6%), alimentary problems (10.85%), mastitis (9.6%) and lameness (8.3%). More detailed epidemiological studies are needed to plan and implement healthcare programs. These programs targeted toward diseases that lead to culling would be prerequisite for a profitable farming.