Faculty of Veterinary Medicine, Department of Animal Production, Aristotle University of Thessaloniki, PO Box 393, 54124 Thessaloniki, Greece.
Animal. 2010 Oct;4(10):1628-33. doi: 10.1017/S1751731110000832.
This simulation study investigated the farm-level economic benefits of a genetic improvement scheme using artificial insemination (AI) with fresh ram semen in dairy sheep of the Chios breed in Greece. Data were collected from 67 farms associated with the Chios Sheep Breeders' Cooperative 'Macedonia', describing the percentage of ewes that would be artificially inseminated in the flock, pregnancy rate, annual ram costs that could be saved using AI rather than natural mating, expected improvement in milk production, annual costs of semen and feed, milk price and number of years of AI usage. The study considered 77 760 possible scenarios in a 3 × 4 × 4 × 3 × 3 × 3 × 4 × 15 factorial arrangement. Analysis of variance was used to investigate the effect of each factor on farm profitability. All factors considered were statistically significant (P < 0.001), but their effect varied. The number of years using AI had the greatest effect on profitability and farmers should become aware that using AI is a long-term investment. Semen price, pregnancy rate and improvement in milk production also had substantial effects. The price of milk and feed had a considerably lower effect on profitability, as did the annual cost of maintaining rams that would be replaced by AI. A positive annual and cumulative return was achieved in the model within the first 6 years. The cost of semen was estimated at 8€ to 10€ per dose for the first 5 years. Where the annual improvement in milk production was 1% of annual phenotypic mean (e.g. 3.0 kg) profitability of the scheme was improved greatly.
本模拟研究调查了在希腊基奥绵羊中使用新鲜公羊精液进行人工授精(AI)的遗传改良计划对农场层面经济效益的影响。数据来自与基奥绵羊饲养者合作社“马其顿”相关的 67 个农场,描述了羊群中需要进行人工授精的母羊比例、受胎率、使用 AI 而不是自然交配可节省的公羊年度成本、预期的产奶量提高、精液和饲料的年度成本、牛奶价格以及 AI 使用年限。该研究在 3×4×4×3×3×3×4×15 阶乘排列中考虑了 77760 种可能的情况。方差分析用于研究每个因素对农场盈利能力的影响。所有考虑的因素均具有统计学意义(P < 0.001),但其影响不同。使用 AI 的年限对盈利能力的影响最大,农民应该意识到使用 AI 是一项长期投资。精液价格、受胎率和产奶量的提高也有很大影响。牛奶和饲料的价格对盈利能力的影响相当低,而通过 AI 取代的公羊的年度维护成本也有一定影响。在模型中,前 6 年内实现了正的年度和累计回报。在最初的 5 年内,精液的成本估计为每剂 8 至 10 欧元。如果每年产奶量提高 1%,即年表型均值的 1%(例如 3.0 公斤),则该计划的盈利能力将大大提高。