成母牛配种前发病对配种受胎率的影响分析

Analysis of the Influence of Disease before Insemination the Conception Rate of Cows

[目的]分析2020—2022年318个奶牛场3403957条成母牛配种事件及配种受胎率,旨在分析不同胎次、配种次数、产后天数下不同发病间隔天数分组对应受胎率情况。[方法]对牛只配种前发病间隔天数进行分组,根据各分组内牛只配种事件与配种结果进行统计,并计算受胎率,配种怀孕事件数占配种实际总数(已知孕检结果)的比例,对比不同维度下发病间隔天数分组对应受胎率的差异。[结果](1)配种前发病间隔天数>30天分组对应1胎、2胎、3胎、4胎、5胎及以上受胎率分别为43.6%、41.1%、40.6%、39.4%、37.8%;配种前发病间隔天数0~5天、6~10天分组各胎次对应受胎率24%~30%,29%~33%,较基准低10~14个百分点。(2)配种前发病间隔天数>30天分组对应产后120天以内,121~210天,211~300天,300天以上受胎率分别为41%~48%,35%~40%、33%~34%、32.6%;配种前发病间隔天数0~5天、6~10天分组各胎次对应受胎率22%~28%,25%~33%。(3)配种前发病间隔天数>30天分组对应第1次,第2次,第3次,第4次,第5次,第6次,第7~9次,第10次及以上配种受胎率分别为47.8%、42.6%、40.8%、37.4%、33.8%、30.8%、23%~28%、17.9%;配种前发病间隔天数0~5天、6~10天分组各配种次数对应受胎率17%~30%,16%~33%。(4)当牛只配次超过7次及以上,配种受胎率均低于30%。[结论]为精细化繁殖管理,奶牛场可以设定自己的最低可接受的受胎率标准,如以受胎率30%为界限判断是否配种,2胎及以上牛只发病后0~5天不适合配种,可以主动停配;不同泌乳天数和不同配种次数下牛只发病后0~5天,均不适合配种,可以主动停配。从而根据奶牛场牛只发病后实际情况,做到精细化配种方案,提高配种受胎率,节省人工和冻精成本。

[Objective]By analyzing dairy cows’3403957 breeding events in 318 dairy farms from 2020 to 2022,the aim was to analyze the corresponding conception rate of different parity,breeding times,and days after calving in different disease interval groups.[Method]By grouping the days between onset of diseases before breeding(disease interval),and calculating the conception rate based on the breeding events and results within each group.Conception rates was equal to the proportion of breeding pregnancy events to the actual total number of breeding events(known pregnancy test results),and the differences of conception rate corresponding to the disease interval under different dimensions were compared.[Result]The results showed that:(1)The conception rates of first pairty,second pairty,third pairty,forth pairty,and more than fifth pairty were 43.6%,41.1%,40.6%,39.4%and 37.8%in the group with a disease interval of more than 30 days before insemination.The corresponding conception rates of each pairty in the group with a disease interval of 0~5 days and 6~10 days before insemination were 24%~30%,29%~33%and 10~14 percentage points lower than baseline.(2)The conception rates within 120 days after calving,121~210 days after calving,211~300 days after calving,and over 300 days after calving were 41%~48%,35%~40%,33%~34%and 32.6%in the groups with a disease interval more than 30 days before insemination.The corresponding conception rates with a disease interval of 0~5 days and 6~10 days before insemination were 22%~28%,25%~33%,respectively.(3)The conception rates of the first,second,third,fourth,fifth,sixth,7~9th and more than 10th breed times with a disease interval more than 30 days before insemination were 47.8%,42.6%,40.8%,37.4%,33.8%,30.8%,23%~28%and 17.9%,respectively.The corresponding conception rates with a disease interval of 0~5 days and 6~10 days before insemination were 17%~30%,16%~33%,respectively.(4)When cows’breed times more than 7,the breeding conception rate is lower than 30%.Therefore,in order to refine breeding management,farmers can set their own minimum acceptable conception rate standards,such as judging whether to breed a cow based on a conception rate of 30%.[Conclusion]Cows’parity more than two are not suitable for breeding within 0~5 days after suffering a disease,and stop breeding initiatively.Under different days after calvings and different breeding times,cows are not suitable for breeding from 0 to 5 days after suffering a disease,and can stop breeding initiatively,and so on.Based on the actual situation of cows in the farm after suffering a disease,a refined breeding plan can help the famer improve cows’conception rate,save labor and frozen semen costs.