Study on the relationship between weaning age,growth rate and milk production performance of calves

Chen Shiwei; Jiang Hui; Huang Wangzhou; Wang Hongbin; Li Xiaorui; Ma Tiaotiao; Tao Yongkang

doi:10.20154/j.cnki.issn1672-9692.2025.01.010

Abstract：The aim of the experiment was to investigate the effects of different weaning days on the growth performance and health status of calves in later period,and the effects of different average daily gain of 0～180 days of age on milk production in the first lactation of adult calves.A total of 1 105 Holstein female calves born from 2020 to 2022 on a large-scale dairy farm in Gansu Province were divided into seven groups according to their weaning age.The weight of the calves at weaning and 180 days of age and the average daily gain at the corresponding stage were calculated.And the incidence of diarrhea,pneumonia,or other diseases in female calves in each group during the trial.According to the average daily gain at 0～60 days of age and 61～180 days of age,cows were divided into five groups and six groups,respectively.The peak day of first fetal milk production,peak milk yield and 305 d milk yield of cows in each group with different average daily gain at the two stages were calculated respectively.The results showed that the average daily gain from birth to weaning and from birth to 180 days of age and the weight at 180 days of age were higher in Holstein female calves weaned at 56～58 days of age.Increasing weaning weight can significantly improve the health status of calves after weaning.The average daily gain of 0.86～0.90 kg/(calves·d)at 0～60 days of age could significantly increase the milk yield of Holstein female calves in the first lactation of adult(P<0.05).An average daily gain of 1.21 kg/(calves·d)or more at 61～180 days of age could achieve the highest milk yield in the first lactation and 305 days of adult Holstein female calves.The results showed that the selection of suitable weaning age and average daily gain at different stages in the breeding process of calves could not only improve the milk production performance in the first lactation period of adult calves,but also reduce the breeding cost of calves.The results could provide reference for the future reserve cattle breeding in Gansu Province.