In Spain, ewe milk is mainly used for cheesemaking, and farming systems have traditionally been based on the use of autochthonous breeds. However, in recent years, the progressive introduction of highly productive foreign breeds in Spanish farms has led to an increasing interest in the characterization of dairy sheep breeds to evaluate whether genetic selection schemes should focus on productivity or milk technological aptitude. The purpose of this work was to explore milk composition and coagulation to classify 4 of the main dairy sheep breeds used in Spain. This study included 832 individual ewe milk samples from the breeds Manchega, Assaf, Merino de Grazalema, and Merino de Los Pedroches. Samples were analyzed for native pH, composition (fat, protein, lactose, and total solids), coagulation properties, and individual laboratory curd yield. An indicator of coagulation efficiency was also determined. Canonical discriminant analysis was performed to establish differences and similarities among breeds based on the measured variables. In addition, cluster analysis was performed to study and quantify the concrete relationships among the discriminated groups. Discriminant analysis proved to be a powerful tool to accurately draw distinctions between breeds. In all cases, discrimination among breeds was evident and the 4 breeds could be easily differentiated. Cluster analysis showed greater similarity between Merino de Grazalema and Assaf compared with the other breeds, and F-statistics indicated a higher discriminating ability for the variables related to milk composition. However, Merino de Grazalema and Manchega were difficult to separate according to milk composition, but the coagulation process differenced them clearly. Coagulation also evidenced similarities between Manchega and Merino de Los Pedroches, although the latter was revealed to be the most different breed of all 4, which could lay the ground for its differentiation as an independent breed in the Official Catalogue of Spanish Livestock Breeds.

在西班牙，母乳牛奶主要用于奶酪生产，传统上，养殖系统是基于土生品种的使用。然而，近年来，西班牙农场逐渐引进高产外国品种，从而引起了人们对表征奶牛羊品种以评估基因选择方案是否应侧重生产力或牛奶技术能力的兴趣。这项工作的目的是探索牛奶的成分和混凝作用，以对西班牙使用的4种主要奶牛羊品种进行分类。这项研究包括来自Manchega，Assaf，Merino de Grazalema和Merino de Los Pedroches品种的832个母羊奶样品。分析样品的天然pH值，组成（脂肪，蛋白质，乳糖和总固体），混凝特性以及各个实验室的凝乳收率。还确定了凝血效率的指标。进行典型判别分析以根据测得的变量确定品种之间的差异和相似性。另外，进行了聚类分析以研究和量化被区分的群体之间的具体关系。判别分析被证明是准确区分品种之间的有力工具。在所有情况下，品种间的区别都是明显的，并且可以容易地区分这4个品种。聚类分析显示，与其他品种相比，美利奴德格拉扎莱玛和阿萨夫之间的相似度更高，并且 进行聚类分析以研究和量化被区分的群体之间的具体关系。判别分析被证明是准确区分品种之间的有力工具。在所有情况下，品种间的区别都是明显的，并且可以容易地区分这4个品种。聚类分析显示，与其他品种相比，美利奴德格拉扎莱玛和阿萨夫之间的相似度更高，并且 进行聚类分析以研究和量化被区分的群体之间的具体关系。判别分析被证明是准确区分品种之间的有力工具。在所有情况下，品种间的区别都是明显的，并且可以容易地区分这4个品种。聚类分析显示，与其他品种相比，美利奴德格拉萨莱玛和阿萨夫之间的相似度更高，并且F统计量表明，与牛奶成分有关的变量具有较高的判别能力。然而，根据牛奶成分很难分离出美丽诺（Merino de Grazalema）和曼奇加（Manchega），但是在凝结过程上却有明显区别。凝结也证明了曼切加和美利奴德洛斯佩德罗什之间的相似性，尽管后者被认为是所有4种中最不同的品种，这可能为其在西班牙畜牧品种官方目录中作为独立品种的分化奠定了基础。