Abstract: [Objective] By analyzing dairy cows’ 3 403 957 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.

Key words: dairy cow, conception rate, disease, insemination