Development of bovine estrous synchronization program adapted for small scale Japanese livestock industry

为了恢复分娩后的生殖功能，采用激素治疗恢复卵巢功能，并对未怀孕奶牛进行早孕诊断和再同步。这些同步方法适用于小规模的日本畜牧业。日本黑牛（n=50）在分娩后第30天进行生殖器官新鲜检查，有黄体（CL）的奶牛用前列腺素F2 arufa （PGF2a）治疗，没有黄体（CL）的奶牛用GnRH治疗。7 d后，阴道内插入孕酮装置（prd、CIDR） 7-9 d，拔出时注射PGF2a。24 h注射雌二醇- 17 β (E2)或48h注射GnRH， 16 ~ 20 h后进行定时人工授精（AI）。术后第10天行CL同步顺应性检测，术后第28天行超声早期妊娠试验。在荷斯坦奶牛（n=40）中，进行了类似的方案……进行了更多的ol，但2周后进行了初始治疗，7天后进行了黄体酮注射。结果表明，日本黑牛和荷斯坦牛新鲜检查时卵巢中CL含量分别为35 ~ 40%和45 ~ 70%，不同奶牛组的CL含量不同。在prd或CIDR拔除后进行定时人工智能的占97.5%，10 d后确诊CL的占90-95%，无品种差异。早孕试验受孕率日本黑牛为35 ~ 60%，荷斯坦牛为27 ~ 53%，GnRH处理优于E2处理。妊娠试验中未妊娠奶牛卵巢表现为退情46%、早潮15%、发情前期22%、卵巢囊肿14%、退情3%。对未怀孕奶牛进行再同步，对有CL的奶牛注射PGF2a，对没有CL或卵巢囊肿的奶牛注射CIDR。再同步后1周内观察发情，40%受孕率进行人工授精。受孕率与对照奶牛相当，但第二次人工智能是在第31.2天进行的，而对照组是在第56天进行的。结论：早期恢复生殖道和卵巢功能是提高奶牛妊娠率的关键。发情或发情同步检测和定时人工智能是现代畜牧业的必要条件。人工智能后，超声早期妊娠试验对未怀孕奶牛的检测具有重要意义，对未怀孕奶牛进行再同步和人工智能。少

In order to recover the reproductive function from parturition, hormonal treatment was developed for resumption of ovarian function, and early pregnancy diagnosis together with resynchronization for non-pregnant cows was conducted. These synchronization methods were adapted for the small scale Japanese livestock industry.In Japanese black cows (n=50), fresh check of reproductive organs was conducted on day 30 after parturition, and cows with corpus luteum (CL) was treated with Prostaglandin F2 arufa (PGF2a) and cows without CL was treated with GnRH. 7 days later, progesterone devices (PRID, CIDR) was inserted for vagina for 7-9 days and PGF2a was injected when they were pulled. Estradiol - 17 beta (E2) on 24 h or GnRH on 48h was injected and timed artificial insemination (AI) was performed 16-20 h later. On day 10 after AI, CL was detected for synchronization compliance and early pregnancy test by ultrasonography was conducted on day 28 after AI. In Holstein cows (n=40), similar protoc … More ol was performed, but initial treatment was conducted 2 weeks later followed with progesterone insertion seven days later.In the results, CL was existed in the ovary at fresh check for 35-40% in Japanese black cows and 45-70% in Holsteins, and these were varied depend on the cow group. Timed AI was performed for 97.5% after pull of PRID or CIDR, CL was confirmed 10 days later for 90-95%, and there was no breed difference. Conception rate at early pregnancy test was varied for 35-60% in Japanese black cows and 27-53% in Holsteins, and GnRH treatment was superior to E2 treatment.Ovarian findings in non-pregnant cows at pregnancy test were diestrus 46%, metestrus 15%, proestrus 22%, ovarian cysts 14% and anestrus 3%. Resynchronization was performed for non-pregnant cows in which PGF2a was injected for cows with CL while as CIDR was inserted for cows without CL or ovarian cysts. Estrus was observed within a week after resynchronization, and AI was performed with 40% conception. Conception rate was comparable to control cows, but second AI was performed on day 31.2 after initial AI in resynchronized cows compared to day 56 in controls.In conclusion, early resumption of reproductive tract and ovarian function were keys for the improvement of pregnancy rate in cow herd. Detection of estrus or estrous synchronization and timed AI were necessary for the modern livestock industry. After AI, early pregnancy test by ultrasonography was important for detection of non-pregnant cows, which were subjected for resynchronization and AI. Less