Ferro M M, Tedeschi L O, Atzori A S
Department of Animal Science, Texas A&M University, College Station 77843-2471.
Departmento de Zootecnia, Universidade Federal de Mato Grosso, Cuiabá 78020, Brazil.
Transl Anim Sci. 2017 Dec 1;1(4):498-506. doi: 10.2527/tas2017.0056. eCollection 2017 Dec.
The objective of this study was to characterize the milk yield (MY) and milk composition of relevant sheep and goat breeds raised around the world to be used with nutrition models for diet formulation and nutrient balancing. A 2-step approach was used. First, a database developed by the Food and Agriculture Organization was used to identify relevant breeds (i.e., frequently raised) by comparing the occurrence of transboundary breed names across countries. We selected transboundary breeds that occurred more than 3 times and other relevant breeds obtained from the specialized literature that had milk production information (e.g., MY, days in milk, and milk fat, protein, and lactose). The majority of sheep breeds were classified as nondairy (76%) because they lacked milk production information. Karakul and Merino accounted for up to 2.4% of sheep breeds raised around the world, whereas the other individual breeds accounted for less than 1%. In contrast, nondairy breeds of goats accounted for 46.3% and of the remaining 53.7%, Saanen, Boer, Anglo-Nubian, Toggenburg, and Alpine accounted for 6.5, 5, 4.4, 4, and 3%, respectively, of the transboundary breeds. Second, a database compiled from published studies for the selected sheep ( = 65) and goats ( = 78) breeds were analyzed using a random coefficients model (studies and treatments within studies as random effects). For sheep breeds, the average and SD were 1.1 ± 0.3 kg/d for MY, 6.9 ± 1% for milk fat, 5.4 ± 0.4% for milk protein, 5 ± 0.3% for milk lactose, 17.7 ± 1.4% for milk total solids, and 1,073 ± 91 kcal/kg of milk energy. Lacaune had the greatest MY compared to Comisana and Tsigai (1.65 versus 0.83 and 0.62 kg/d; respectively, < 0.05), but milk components were not different among breeds. For goats breeds, the average and SD across breeds were 1.7 ± 0.6 kg/d for MY, 4.2 ± 0.9% for milk fat, 3.3 ± 0.4% for milk protein, 4.4 ± 0.4% for milk lactose, 12.7 ± 1.1% for milk total solids, and 750 ± 75 kcal/kg of milk energy. Alpine had similar MY to Saanen (2.66 versus 2.55 kg/d, respectively; > 0.05), but greater ( < 0.05) than other breeds. The Boer breed had the greatest milk fat, protein, lactose, and total solids than several other breeds, leading to the greatest milk energy content (907 kcal/kg). Because there are many factors that can alter MY and milk composition, averages provided in this study serve as guidelines, and nutritionists must obtain observed values when using nutrition models.
本研究的目的是描述世界各地养殖的相关绵羊和山羊品种的产奶量（MY）和乳汁成分，以便用于日粮配方和营养平衡的营养模型。采用了两步法。首先，利用联合国粮食及农业组织开发的数据库，通过比较各国跨界品种名称的出现情况来确定相关品种（即养殖频繁的品种）。我们选择了出现次数超过3次的跨界品种以及从有产奶信息（如产奶量、泌乳天数、乳脂肪、蛋白质和乳糖）的专业文献中获取的其他相关品种。大多数绵羊品种被归类为非乳用品种（76%），因为它们缺乏产奶信息。卡拉库尔羊和美利奴羊占全球养殖绵羊品种的2.4%，而其他单个品种占比不到1%。相比之下，非乳用山羊品种占46.3%，其余53.7%中，萨能山羊、波尔山羊、盎格鲁-努比亚山羊、吐根堡山羊和阿尔卑斯山羊分别占跨界品种的6.5%、5%、4.4%、4%和3%。其次，使用随机系数模型（将研究和研究内的处理作为随机效应）对从已发表研究中汇编的所选绵羊（n = 65）和山羊（n = 78）品种的数据库进行分析。对于绵羊品种，产奶量的平均值和标准差分别为1.1±0.3千克/天，乳脂肪为6.9±1%，乳蛋白为5.4±0.4%，乳糖为5±0.3%，总固体为17.7±1.4%，每千克乳能量为1073±91千卡。与科米萨纳羊和齐盖羊相比，拉科讷羊的产奶量最高（分别为1.65千克/天对0.83千克/天和0.62千克/天；P < 0.05），但各品种间的乳汁成分无差异。对于山羊品种，各品种的产奶量平均值和标准差分别为1.7±0.6千克/天，乳脂肪为4.2±0.9%，乳蛋白为3.3±0.4%，乳糖为4.4±0.4%，总固体为12.7±1.1%，每千克乳能量为750±75千卡。阿尔卑斯山羊的产奶量与萨能山羊相似（分别为2.66千克/天对2.55千克/天；P > 0.05），但高于其他品种（P < 0.05）。波尔山羊的乳脂肪、蛋白质、乳糖和总固体含量高于其他几个品种，导致其乳能量含量最高（907千卡/千克）。由于有许多因素会改变产奶量和乳汁成分，本研究提供的平均值仅作为指导，营养学家在使用营养模型时必须获取实测值。
