Zapata Rizaldy C, Salehi Reza, Ambrose Divakar J, Chelikani Prasanth K
Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta T2N 4N1 Canada.
Department of Agricultural, Food and Nutritional Science, University of Alberta, 410 Agriculture/Forestry Centre, Edmonton, Alberta T6G 2P5 Canada.
J Dairy Sci. 2015 Oct;98(10):6876-85. doi: 10.3168/jds.2014-9283. Epub 2015 Jul 22.
Dietary fat supplementation during the periparturient period is one strategy to increase energy intake and attenuate the degree of negative energy balance during early lactation; however, little is known of the underlying hormonal and metabolic adaptations. We evaluated the effects of prepartum fat supplementation on energy-balance parameters and plasma concentrations of glucagon-like peptide-1, peptide tyrosine-tyrosine (PYY), adropin, insulin, leptin, glucose, nonesterified fatty acid, and β-hydroxybutyric acid in dairy cows. Twenty-four pregnant dairy cows were randomized to diets containing either rolled canola or sunflower seed at 8% of dry matter, or no oilseed supplementation, during the last 5 wk of gestation and then assigned to a common lactation diet postpartum. Blood samples were collected at -2, +2, and +14 h relative to feeding, at 2 wk after the initiation of the diets, and at 2 wk postpartum. Dietary canola and sunflower supplementation alone did not affect energy balance, body weight, and plasma concentrations of glucagon-like peptide-1, PYY, adropin, insulin, leptin, nonesterified fatty acid, and β-hydroxybutyric acid; however, canola decreased and sunflower tended to decrease dry matter intake. We also observed that the physiological stage had a significant, but divergent, effect on circulating hormones and metabolite concentrations. Plasma glucagon-like peptide-1, PYY, adropin, nonesterified fatty acid, and β-hydroxybutyric acid concentrations were greater postpartum than prepartum, whereas glucose, insulin, leptin, body weight, and energy balance were greater prepartum than postpartum. Furthermore, the interaction of treatment and stage was significant for leptin and adropin, and tended toward significance for PYY and insulin; only insulin exhibited an apparent postprandial increase. Postpartum PYY concentrations exhibited a strong negative correlation with body weight, suggesting that PYY may be associated with body weight regulation during the transition period. These novel findings demonstrate that the transition from pregnancy to lactation is a stronger determinant of circulating gut hormone concentrations than dietary lipid in transition dairy cows.
围产期补充膳食脂肪是增加能量摄入并减轻泌乳早期负能量平衡程度的一种策略；然而，对于潜在的激素和代谢适应性变化知之甚少。我们评估了产前补充脂肪对奶牛能量平衡参数以及胰高血糖素样肽 -1、肽YY（PYY）、内脂素、胰岛素、瘦素、葡萄糖、非酯化脂肪酸和β - 羟基丁酸血浆浓度的影响。24头怀孕奶牛在妊娠最后5周被随机分配到含有占干物质8%的压碎油菜籽或向日葵籽的日粮组，或不补充油籽的日粮组，产后则采用共同的泌乳日粮。在喂食后 -2、+2和 +14小时、日粮开始2周后以及产后2周采集血样。单独补充油菜籽和向日葵籽日粮对能量平衡、体重以及胰高血糖素样肽 -1、PYY、内脂素、胰岛素、瘦素、非酯化脂肪酸和β - 羟基丁酸的血浆浓度没有影响；然而，油菜籽组降低了干物质摄入量，向日葵籽组有降低干物质摄入量的趋势。我们还观察到生理阶段对循环激素和代谢物浓度有显著但不同的影响。产后血浆胰高血糖素样肽 -1、PYY、内脂素、非酯化脂肪酸和β - 羟基丁酸浓度高于产前，而葡萄糖、胰岛素、瘦素、体重和能量平衡则产前高于产后。此外，处理和阶段的相互作用对瘦素和内脂素具有显著意义，对PYY和胰岛素有显著趋势；只有胰岛素表现出明显的餐后增加。产后PYY浓度与体重呈强负相关，表明PYY可能与过渡期奶牛的体重调节有关。这些新发现表明，从怀孕到泌乳的转变比围产期奶牛日粮中的膳食脂质更能决定循环肠道激素浓度。
