Gross J J, Grossen-Rösti L, Héritier R, Tröscher A, Bruckmaier R M
Veterinary Physiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
BASF SE, Lampertheim, Germany.
J Anim Physiol Anim Nutr (Berl). 2018 Apr;102(2):e838-e848. doi: 10.1111/jpn.12843. Epub 2017 Nov 26.
Supplementation of dairy cows with trans-10, cis-12 conjugated linoleic acid (CLA) allows nutrient repartitioning despite an energy deficiency in early lactation, which might be a benefit for the immune system, too. In this study, we investigated potential nutrient sparing effects of CLA in early lactating cows with low plasma glucose concentrations exposed to an intramammary lipopolysaccharide (LPS) challenge. Fifteen multiparous Holstein cows were exposed to an intramammary LPS challenge in week 4 p.p. Eight cows (CLA) were supplemented daily with 70 g of lipid-encapsulated CLA (6.8 g trans-10, cis-12 and 6.6 g of the cis-9, trans-11 CLA isomer; CLA) and seven cows with 56 g of control fat (CON). Blood samples were obtained every 30 min along with rectal temperature, heart and respiratory rate, and milk samples were taken hourly until 10 hr after the LPS application. Plasma was analysed for concentrations of glucose, free fatty acids, beta-hydroxybutyrate (BHB), cortisol, insulin and glucagon. In milk, somatic cell count and activity of lactate dehydrogenase were determined. Initial plasma glucose concentration was lower in CLA than in CON. During the immunostimulation, CLA had higher glucose concentrations than CON, and BHB decreased distinctly in CLA, whereas CON cows maintained BHB concentration at a lower level. Body temperature in CLA increased earlier, the difference between peak and basal temperature was higher, and the decline thereafter occurred earlier. In conclusion, CLA supplementation of early lactating cows exposed to an intramammary LPS challenge affected local and systemic immune responses. We assume that CLA supplementation triggered glycogen storage. Cows supplemented with CLA provided more glucose and preferentially used BHB as an energy source during the immune response. The more intense metabolic and more concentrated endocrine responses support an immunomodulatory effect of CLA supplementation.
给奶牛补充反式-10，顺式-12共轭亚油酸（CLA），尽管在泌乳早期存在能量不足，但仍能实现营养重新分配，这可能对免疫系统也有益处。在本研究中，我们调查了CLA对血浆葡萄糖浓度较低的初产奶牛在接受乳房内脂多糖（LPS）刺激时潜在的营养节约效应。15头经产荷斯坦奶牛在产后第4周接受乳房内LPS刺激。8头奶牛（CLA组）每天补充70克脂质包封的CLA（6.8克反式-10，顺式-12和6.6克顺式-9，反式-11 CLA异构体；CLA），7头奶牛补充56克对照脂肪（CON组）。每隔30分钟采集一次血样，同时记录直肠温度、心率和呼吸频率，并每小时采集一次奶样，直至LPS注射后10小时。分析血浆中葡萄糖、游离脂肪酸、β-羟基丁酸（BHB）、皮质醇、胰岛素和胰高血糖素的浓度。测定牛奶中的体细胞计数和乳酸脱氢酶活性。CLA组的初始血浆葡萄糖浓度低于CON组。在免疫刺激期间，CLA组的葡萄糖浓度高于CON组，且CLA组的BHB明显下降，而CON组奶牛的BHB浓度维持在较低水平。CLA组的体温升高更早，峰值与基础体温之间的差异更大，随后体温下降也更早。总之，给初产奶牛补充CLA并接受乳房内LPS刺激会影响局部和全身免疫反应。我们推测补充CLA会触发糖原储存。补充CLA的奶牛在免疫反应期间提供了更多葡萄糖，并优先将BHB用作能量来源。更强烈的代谢和更集中的内分泌反应支持了补充CLA的免疫调节作用。
