Abstract：
This study investigates the relationships between subclinical mastitis and milk quality with selected microRNAs in cow milk. California Mastitis Test (CMT)-positive (n = 20) and negative (n = 20) samples were compared (Experiment I). Additionally, samples with CMT-positive but microbiological-negative, as well as positive for only Staphylococcus subspecies (Staph spp.) and only Streptococcus subspecies (Strep spp.) were examined (Experiment II). Four groups were formed in Experiment II: Group I (CMT and microbiological-negative) (n = 20), Group II (CMT-positive but microbiological-negative) (n = 10), Group III (Staph spp.) (n = 5), Group IV (Strep spp.) (n = 5). While electrical conductivity, somatic cell count (SCC), malondialdehyde (MDA) increased, miR-27a-3p and miR-223 upregulated and miR-125b downregulated in the CMT-positive group in Experiment I. SCC and MDA were higher in CMT-positive groups. miR-27a-3p and miR-223 upregulated in Groups III and IV. While miR-155 is upregulated, miR-125b downregulated in Group IV. Milk fat is positively correlated with miR-148a and miR-223. As miR-27a-3p positively correlated with SCC and MDA, miR-125b negatively correlated with electrical conductivity and SCC. miR-148a and MDA were positively correlated. miR-155 was correlated with fat-free dry matter, protein, lactose, and freezing point. miR-223 was positively correlated with SCC and miR-148a. Results particularly highlight miR-27a-3p and miR-223 as potential biomarkers in subclinical mastitis, especially those caused by Staph spp. and Strep spp., while miR-148a, miR-155, and miR-223 stand out in determining milk quality.
摘要：
这项研究调查了亚临床乳腺炎与牛奶质量之间的关系，并选择了牛奶中的microRNA。比较加利福尼亚乳腺炎测试(CMT)阳性(n=20)和阴性(n=20)样品(实验I)。此外,CMT阳性但微生物阴性的样品，以及仅对葡萄球菌亚种呈阳性（葡萄球菌属。）和仅链球菌亚种（Strepspp。)进行了检查(实验二)。在实验II中形成四组：I组（CMT和微生物阴性）（n=20），II组（CMT阳性但微生物阴性）（n=10），第三组（葡萄球菌属。)(n=5)，第四组（链球菌属。)(n=5)。虽然导电性，体细胞计数（SCC），丙二醛（MDA）增加，实验I中CMT阳性组中miR-27a-3p和miR-223上调,miR-125b下调,CMT阳性组中SCC和MDA较高。miR-27a-3p和miR-223在组III和IV中上调。虽然miR-155上调，miR-125b在IV组中下调。乳脂与miR-148a和miR-223呈正相关。由于miR-27a-3p与SCC和MDA呈正相关,miR-125b与电导率和SCC呈负相关。miR-148a与MDA呈正相关。miR-155与无脂干物质相关，蛋白质，乳糖,和冰点。miR-223与SCC和miR-148a呈正相关。结果特别强调miR-27a-3p和miR-223是亚临床乳腺炎的潜在生物标志物。尤其是那些由葡萄球菌引起的。和Strepspp.,而miR-148a,miR-155和miR-223在确定牛奶质量方面脱颖而出。
