反刍动物营养 Ruminant nutrition

不同牛奶体细胞数下牛奶体细胞分型及奶牛泌乳性能变化

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  • 1. 北京农学院动物科学技术学院, 奶牛营养学北京市重点实验室, 北京 102206;
    2. 中国农业科学院北京畜牧兽医研究所, 北京 100193
汪悦(1993-),女,青海西宁人,硕士研究生,研究方向为动物营养与免疫。E-mail:wangyue9313@163.com

收稿日期: 2017-10-18

  网络出版日期: 2018-04-03

基金资助

十三五国家重大科技专项(2016YFDO700201);北京市农业局北京市现代农业产业技术体系奶牛创新团队

Milk Somatic Cell Classification and Changes in Lactation Performance of Dairy Cows under Different Somatic Cell Counts

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  • 1. Key Laboratory of Dairy Nutrition in Beijing, College of Animal Science and Technology, Beijing Agricultural College, Beijing 102206, China;
    2. Beijing Institute of Animal Science and Veterinary Medicine, Chinese Academy of Agricultural Sciences, Beijing 100193, China

Received date: 2017-10-18

  Online published: 2018-04-03

摘要

本试验旨在通过研究不同牛奶体细胞数(SCC)下牛奶体细胞分型特点,进而评估奶牛泌乳性能。选择102头荷斯坦奶牛进行牛奶样品采集,检测SCC、产奶量和乳成分。根据SCC检测结果将这102份牛奶样品分为3组,低SCC组(SCC<100 000个/mL)、中等SCC组(SCC为100 000~400 000个/mL)和高SCC组(SCC>400 000个/mL)。通过流式细胞仪对牛奶样品中的体细胞进行分选,检测淋巴细胞、巨噬细胞和多形核嗜中性白细胞(PMN)的比例。采用标准平板计菌法对菌落总数进行计数,并通过细菌学检查对牛奶样品中的细菌进行分类鉴定。结果表明:1)在SCC<100 000个/mL范围内,SCC在13 000~76 000个/mL时,淋巴细胞比例为89.43%,是健康乳腺中的主要细胞群体,当SCC增加到76 000~100 000个/mL时,PMN比例极显著增加(P<0.01),达到79.68%,成为乳腺内主要细胞群体,表明早期炎症已经开始发生。SCC>200 000个/mL时,PMN比例与SCC呈正相关;淋巴细胞比例与SCC呈负相关;巨噬细胞比例与SCC无明显相关性。2)鉴别出的主要病原体有金黄色葡萄球菌、凝固酶阴性葡萄球菌(CNS)、无乳链球菌等;次要病原体有绿脓杆菌、芽孢杆菌、乳酸乳球菌等。主要病原体组的牛奶样品中PMN比例(48.93%)极显著高于无病原体组(17.23%)(P<0.01),显著高于次要病原体组(P<0.05)。3)细菌培养阳性的牛奶样品中,感染传染型病原体的奶牛,产奶量显著下降(P<0.05),酪蛋白/乳蛋白及乳糖含量显著减少(P<0.05);在细菌培养阴性牛奶样品中,中等SCC(10 000~40 000个/mL)和高SCC(SCC>40 000个/mL)牛奶样品中观察到酪蛋白与和乳糖含量显著降低(P<0.05),高SCC牛奶样品中观察到乳蛋白含量显著降低(P<0.05)。由此可见,体细胞分型可用于对奶牛乳腺健康状况做出更详细分析,特别是在低SCC的牛奶中更早地识别炎症起始发生。乳腺早期炎症反应的发生明显低于目前公认的健康乳腺牛奶SCC阈值(<100 000个/mL),并且CNS可能是诱发早期乳腺炎症的潜在病原体。细菌培养阴性样品中,炎症导致高SCC牛奶中酪蛋白/乳蛋白和乳糖含量的显著降低。

本文引用格式

汪悦, 蒋林树, 熊本海 . 不同牛奶体细胞数下牛奶体细胞分型及奶牛泌乳性能变化[J]. 动物营养学报, 2018 , 30(4) : 1353 -1366 . DOI: 10.3969/j.issn.1006-267x.2018.04.018

Abstract

The aim of this study was to evaluate lactation performance of dairy cows by studying the characteristics of somatic cell classification under different milk somatic cell counts (SCC). A total of 102 Holstein dairy cows were selected for milk sample collection and tested for SCC, milk production and milk composition. According to the results of SCC test, 102 samples were divided into three groups, which were low SCC group (SCC<100 000 cells/mL), medium SCC group (SCC was 100 000 to 400 000 cells/mL) and high SCC group (SCC>400 000 cells/mL). The proportion of lymphocytes, macrophages and polymorphonuclear neutrophils (PMN) were detected by flow cytometry. The total number of bacteria in milk samples was counted by standard plate count method, and the bacterial species in milk samples were classified and identified by bacterial routine identification method. The results showed as follows:1) The proportion of lymphocytes was 89.43% when SCC was between 13 000 and 76 000 cells/mL in the range of SCC<100 000 cells/mL, which was the main cell population in healthy breast. When the SCC increased to 76 000 to 100 000 cells/mL, the proportion of PMN significantly increased (P<0.01), reached 79.68%, and became the main cell population in the breast, indicating that early inflammation has begun to occur. When SCC>200 000 cells/mL, the proportion of PMN was positively correlated with SCC; the proportion of lymphocytes was negatively correlated with SCC; there was no significant correlation between the proportion of macrophages and SCC. 2) The main pathogens identified were Staphylococcus aureus, coagulase-negative Staphylococcus (CNS), Streptococcus agalactiae, etc.; secondary pathogens were Pseudomonas aeruginosa, Bacillus, Lactococcus lactis and so on. The proportion of PMN in the milk samples of the major pathogens (48.93%) was significantly higher than that of the non-pathogens (17.23%) (P<0.01), and was significantly higher than that of the secondary pathogens (P<0.05). 3) Milk yield of cows infected with contagious pathogens decreased significantly (P<0.05), and casein/milk protein and lactose content decreased significantly (P<0.05); in culture-negative milk samples, casein and lactose contents were significantly reduced in medium SCC (10 000 to 40 000 cells/mL) and high SCC (SCC>40 000 cells/mL) milk samples (P<0.05), and milk protein content was significantly reduced in high SCC (SCC>40 000 cells/mL) milk samples (P<0.05). From this, it can be seen that somatic cell classification can be used to make a more detailed analysis for mammary gland health status of dairy cows, especially early onset of inflammation in low-SCC milk. The incidence of early breast inflammation is significantly lower than the currently accepted threshold for healthy breast milk (<100 000 cells/mL), and CNS may be a potential pathogen for early breast inflammation. In bacterial culture-negative milk samples, inflammation leads to a significant decrease in casein/milk protein and lactose content in high SCC milk.

参考文献

[1] HARMON R J.Physiology of mastitis and factors affecting somatic cell counts[J].Journal of Dairy Science,1994,77(7):2103-2112.  

[2] HOWARD C J,NAESSENS J.Summary of workshop findings for cattle (tables 1 and 2)[J].Veterinary Immunology and Immunopathology,1993,39(1/2/3):25-47.

[3] KEHRLI K M,Jr.,SHUSTER D E.Factors affecting milk somatic cells and their role in health of the bovine mammary gland[J].Journal of Dairy Science,1994,77(2):619-627.  

[4] KOESS C,HAMANN J.Detection of mastitis in the bovine mammary gland by flow cytometry at early stages[J].Journal of Dairy Research,2008,75(2):225-232.

[5] LEE C S,WOODING F B P,KEMP P.Identification,properties,and differential counts of cell populations using electron microscopy of dry cows secretions,colostrum and milk from normal cows[J].Journal of Dairy Research,1980,47(1):39-50.  

[6] LEITNER G,ELIGULASHVILY R,KRIFUCKS O,et al.Immune cell differentiation in mammary gland tissues and milk of cows chronically infected with Staphylococcus aureus[J].Journal of Veterinary Medicine,2003,50(1):45-52.  

[7] LOKEN M R,STALL A M.Flow cytometry as an analytical and preparative tool in immunology[J].Journal of Immunological Methods,1982,50(3):R85-R112.

[8] AULDIST M J,COATS S,SUTHERLAND B J,et al.Effects of somatic cell count and stage of lactation on raw milk composition and the yield and quality of Cheddar cheese[J].Journal of Dairy Research,1996,63(2):269-280.  

[9] AULDIST M J,HUBBLE I B.Effects of mastitis on raw milk and dairy products[J].Australian Journal of Dairy Technology,1998,53(1):28-36.

[10] BANNERMAN D D,PAAPE M J,LEE J W,et al.Escherichia coli and Staphylococcus aureus elicit differential innate immune responses following intramammary infection[J].Clinical and Diagnostic Laboratory Immunology,2004,11(3):463-472.

[11] MAURMAYR A,CECCHINATO A,GRIGOLETTO L,et al.Detection and quantification of αs1-,αs2-,β-,κ-casein,α-lactalbumin,β-lactoglobulin and lactoferrin in bovine milk by reverse-phase high-performance liquid chromatography[J].Agriculturae Conspectus Scientificus,2013,78(3):201-205.

[12] LI N,ROMAIN R,MARIE-HÉLÈNE P,et al.Flow cytometry approach to quantify the viability of milk somatic cell counts after various physico-chemical treatments[J].PLoS One,2015,10(12):e0146071.

[13] 王素英.细菌平板菌落计数的改进方法[J].生物学通报,2003,28(2):41.

[14] 陈艳.微生物鉴定方法的比较[J].中国水产,2005(1):69.

[15] HISS S,MUELLER U,NEU-ZAHREN A,et al.Haptoglobin and lactate dehydrogenase measurements in milk for the identification of subclinically diseased udder quarters[J].Veterinarni Medicina,2007,52(6):245-252.

[16] HORTET P,SEEGERS H.Calculated milk production losses associated with elevated somatic cell counts in dairy cows:review and critical discussion[J].Veterinary Research,1998,29(6):497-510.

[17] KESTER H J,SORTER D E,HOGAN J S.Activity and milk compositional changes following experimentally induced Streptococcus uberis bovine mastitis[J].Journal of Dairy Science,2014,98(2):999-1004.

[18] KITCHEN B J.Review of the progress of dairy science:bovine mastitis:milk compositional changes and related diagnostic tests[J].Journal of Dairy Research,1981,48(1):167-188.  

[19] GEARY U,LOPEZ-SHALLOO L,O'BRIEN B,et al.Meta-analysis to investigate relationships between somatic cell count and raw milk composition,Cheddar cheese processing characteristics and cheese composition[J].Irish Journal of Agricultural and Food Ressearch,2013,52(2):119-133.

[20] LABEN R C.Factors responsible for variation in milk composition[J].Journal of Dairy Science,1963,46(11):1293-1301.  

[21] MILLER R H,PAAPE M J,FILEP R,et al.Flow cytometric analysis of neutrophils in cows' milk[J].American Journal of Veterinary Research,1993,54(12):1975-1979.

[22] LE MARÉCHAL C,THIÉRY R,VAUTOR E,et al.Mastitis impact on technological properties of milk and quality of milk products-a review[J].Dairy Science & Technology,2011,91(3):247-282.  

[23] LE ROUX Y,GIRARDET J M,HUMBERT G,et al.Proteolysis in samples of quarter milk with varying somatic cell counts.2.component PP3 and β-casein-lP (f29-105 and f29-107) of the proteose-peptone fraction[J].Journal of Dairy Science,1995,78(6):1298-1305.  

[24] LEITNER G,MERIN U,SILANIKOVE N.Effects of glandular bacterial infection and stage of lactation on milk clotting parameters:comparison among cows,goats and sheep[J].International Dairy Journal,2011,21(4):279-285.  

[25] DOS REIS C B M,BARREIRO J R,MESTIERI L,et al.Effect of somatic cell count and mastitis pathogens on milk composition in Gyr cows[J].BMC Veterinary Research,2013,9:67.

[26] MAZAL G,VIANNA P C,SANTOS M V,et al.Effect of somatic cell count on Prato cheese composition[J].Journal of Dairy Science,2007,90(2):630-636.  

[27] MERIN U,FLEMINGER G,KOMANOVSKY J,et al.Subclinical udder infection with Streptococcus dysgalactiae impairs milk coagulation properties:the emerging role of proteose peptones[J].Dairy Science & Technology,2008,88(4/5):407-419.

[28] NEWBOULD F H S,NEAVE F K.The recovery of small numbers of Staphylococcus aureus infused into the bovine teat cistern[J].Journal of Dairy Research,1965,32(2):157-162.  

[29] PARADIS M È,BOUCHARD É,SCHOLL D T,et al.Effect of nonclinical Staphylococcus aureus or coagulase-negative staphylococci intramammary infection during the first month of lactation on somatic cell count and milk yield in heifers[J].Journal of Dairy Science,2010,93(7):2989-2997.  

[30] POLITIS I,NG-KWAI-HANG K F.Effects of somatic cell count and milk composition on cheese composition and cheese making efficiency[J].Journal of Dairy Science,1988,71(7):1711-1719.  

[31] PYÖRÄLÄ S.Indicators of inflammation in the diagnosis of mastitis[J].Veterinary Research,2003,34(5):565-578.  

[32] REKSEN O,SØLVERØD L,ØSTERÅS O.Relationships between milk culture results and milk yield in Norwegian dairy cattle[J].Journal of Dairy Science,2007,90(10):4670-4678.  

[33] PICCININI R,BINDA E,BELOTTI M,et al.Comparison of blood and milk non-specific immune parameters in heifers after calving in relation to udder health[J].Veterinary Research,2005,36(5/6):747-757.

[34] RIOLLET C,RAINARD P,POUTREL B.Cells and cytokines in inflammatory secretions of bovine mammary gland[M]//MOL J A,CLEGG R A.Biology of the Mammary Gland.Advances in Experimental Medicine and Biology.Boston,MA:Springer,2000.
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