A comprehensive characterization of longevity and culling reasons in Canadian Holstein cattle based on various systematic factors

Abstract The decision of premature culling cows directly impacts the profitability dairy farms. A comprehensive characterization primary causes reasons would greatly improve both management and selection objectives in cattle breeding programs. Therefore, this study aimed to analyze temporal frequencies 34 Canadian Holstein cows. After data editing quality control, records from 3,096,872 culled 9,683 herds spread across Canada were used for analyses covering periods 1996 2020. Reproductive issues main reason accounting 23.02%, followed by milk production (20.82%), health (20.39%), conformation problems (13.69%), economic factors (13.10%), accidents (5.67%), age-related (1.67%), workability (1.63%). Nearly fifty-eight percent after 47 months age. observed due lower than expected 2014 higher between 2015 Reproduction had highest during fall (24.54%), winter (24.02%), spring (22.51%), while most frequent (22.51%) summer season. Health (25.50%) (27.71%) provinces Quebec Ontario, respectively. showed frequency climates based on Köppen climate classification, except Csb (Dry-summer subtropical or Mediterranean climate) Bsk (Middle latitude steppe climate), which correspond small regions Canada, where was (29.42% 21.56%, respectively). performance two ecozones, Boreal Shield Atlantic Marine, (25.12 23.75%, These results will contribute improving practices selective decisions reduce involuntary