EVALUATION OF ALFAGLANDIN C AND ASSOCIATED FACTORS ON EFFICIENCY OF COWS’ ESTRUS SYNCHRONIZATION AND ARTIFICIAL INSEMINATION IN NORTH SHOA OROMIA, ETHIOPIA

Synchronization of estrus involves handling the estrus cycle so that a large number of cows can be bred at approximately the same time. Proper cow/heifer selection as well as efficient coordination are all key elements for the success of synchronization programs which were lacking in the study area. The study was conducted with the objective to evaluate the effect of Alfaglandin C and fixed factors on estrus synchronization and efficiency of Artificial Insemination (AI) in North Shoa zone of the Oromia region. The study population encompassed indigenous and crossbred cows and heifers found in six purposively selected kebeles (smallest administrative unit within a district) from the three selected districts (Wucale, Dagam and Kuyuu). Multistage sampling procedure was used to select target districts, kebeles and experimental cows/heifers. A total of 180 cows and heifers fulfilling estrus synchronization criteria were selected purposively and injected with synchronizing hormone (Alfaglandin C). The level of significance among categorical variables was determined using the chi-square (x2) test. About 70.6% of the cows and heifers injected with Alfaglandin C exhibited estrus. Exhibition of estrus following hormone injection was significantly (p&lt;0.05) lower in Wuchale district compared with that of the other two districts. Likewise, the agroecology, farming system, herd group, and breed had a significant (p&lt;0.05) effect on estrus exhibition. Among cows and heifers inseminated following estrus exhibition, 62.2% conceived as confirmed by pregnancy diagnosis (PD) test conducted at 45-day post AI, which dropped to 58.3% as observed by the PD test conducted three months’ post AI. Agroecology, farming system, herd group, and genotype of cows and heifers showed significant (p&lt;0.05) influence on the conception rate (CR). The highest CR was observed among cows of Kuyuu district, which was significantly (p&lt;0.05) different from that of the other two districts. The overall calving rate was 91.1%. The semi-intensive part of the study also showed better estrus synchronization response and better reproductive performances which directly associated with the management practices. Treating industrial byproducts, better management, and promoting AI can achieve better estrus synchronization and efficiency of artificial insemination.发情同步化指通过调控发情周期，使大量母牛能够在大致相近的时间内完成配种。合理的母牛与青年母牛筛选、高效的流程协调，均为发情同步化方案成功实施的关键要素，而这些要素在本研究覆盖区域均存在不足。本研究于埃塞俄比亚奥罗米亚州北绍阿地区开展，旨在评估阿法前列素C（Alfaglandin C）及固定因子对发情同步化效果与人工授精（Artificial Insemination，AI）效率的影响。研究群体涵盖选自3个选定地区（武查莱、达加姆与库尤）中6个经目的抽样选取的凯贝莱（kebele，地区内最小行政单元）内的本地母牛、杂交母牛及青年母牛。本研究采用多阶段抽样法选取目标地区、凯贝莱及试验用母牛与青年母牛，最终共筛选出180头符合发情同步化判定标准的个体，并为其注射同步化激素阿法前列素C（Alfaglandin C）。本研究采用卡方（χ²）检验对分类变量的组间显著性差异进行分析。结果显示，注射阿法前列素C后，约70.6%的受试母牛与青年母牛表现出发情症状；武查莱地区的发情表现率显著低于另外两个地区（P<0.05）。此外，农业生态区类型、养殖系统、畜群组别与品种均对发情表现率存在显著影响（P<0.05）。在表现出发情症状后接受人工授精的个体中，62.2%在人工授精后45天通过妊娠诊断（pregnancy diagnosis，PD）试验确认妊娠；而在人工授精3个月后开展的PD试验中，这一妊娠比例降至58.3%。农业生态区类型、养殖系统、畜群组别及母牛与青年母牛的基因型对受胎率（conception rate，CR）均存在显著影响（P<0.05）；库尤地区母牛的受胎率最高，且与另外两个地区存在显著差异（P<0.05）。本研究整体产犊率为91.1%，其中半集约养殖模式的受试群体展现出更优的发情同步化响应与繁殖性能，这与对应的养殖管理措施直接相关。综上，通过合理处理工业副产品、优化养殖管理并推广人工授精技术，可实现更优异的发情同步化效果与人工授精效率。