Physical exercise prepartum to support metabolic adaptation in the transition period of dairy cattle: A proof of concept
Physical exercise prepartum to support metabolic adaptation in the transition period of dairy cattle: A proof of concept
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DOI：
10.1111/jpn.13330
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发表时间：
2020-02-25
影响因子：
2.7
通讯作者：
Hendriks, Wouter H.
中科院分区：
文献类型：
--
作者：
Goselink, Roselinde M. A.;Schonewille, Jan Thomas;Hendriks, Wouter H.
在奶牛中，产奶前后的荷尔蒙变化会引起大量的代谢变化，以支持产奶量。脂肪储备的调动是涉及的变化之一，对肝脏施加新陈代谢负荷。我们假设，在产前通过体育锻炼开始脂肪动员和加工，可以降低产后过度脂肪分解和肝脏脂肪沉积的风险，特别是在身体状况评分(BCS)较高的奶牛中。作为概念验证，32头怀孕的荷斯坦-弗里斯奶牛被选为2×2的实验设计。16头奶牛的BCS<；=3.25(低组)和16头牛的BCS>；=3.25(高组)。每组奶牛被随机分配到两个处理中的一个：STEP组在干旱期每天散步两次，持续45min，而CON组留在室内。治疗在产犊时停止，奶牛被监测到产犊后6周。对16头奶牛进行了肝脏活检，以确定肝脏甘油三酯(TG)浓度。我们发现，计算的能量平衡对分步组产前更负，导致血浆非酯化脂肪酸和β-羟丁酸浓度较高。在产后6周内，运动对干物质摄入量和产奶量均无影响。正如预期的那样，与低组相比，高组奶牛产后肝脏甘油三酯浓度升高，产后直接血浆非酯化脂肪酸含量增加。干燥期的运动可减轻产后肝脏甘油三酯的蓄积，但这似乎与血浆脂蛋白转运增加无关。我们的结论是，产前大量的体力活动可以诱导脂肪分解和脂肪利用，从而开始对哺乳的早期适应。这可能有助于降低产后肝脏甘油三酯过度积聚的风险，特别是在BCS较高的奶牛。
In dairy cattle, the hormonal changes around calving induce large metabolic changes to support milk production. Mobilization of adipose reserves is one of the changes involved, imposing a metabolic load on the liver. We hypothesized that the risk for excessive lipolysis and hepatic lipidosis postpartum can be reduced by starting fat mobilization and processing during the prepartum period by physical exercise, especially in cows with a high body condition score (BCS). As a proof of concept, 32 pregnant Holstein-Friesian dairy cows were selected for a 2 x 2 experimental design. Sixteen cows had a BCS < 3.25 (group LOW) and 16 cows a BCS >= 3.25 (group HIGH). Cows within each group were randomly allocated to one of two treatments: group STEP was walked twice daily for 45 min during the dry period while group CON remained indoors. Treatment was stopped at calving and cows were monitored until 6 weeks after calving. Liver biopsies were taken in a subset of 16 cows to determine liver triglyceride (TG) concentration. We found that calculated energy balance was more negative for group STEP prepartum, resulting in higher plasma non-esterified fatty acids and beta-hydroxybutyrate concentrations. During the first 6 weeks postpartum, neither dry matter intake nor milk yield was affected by exercise. As expected, the cows in group HIGH had increased liver TG concentrations postpartum relative to group LOW with increased plasma non-esterified fatty acids directly after calving. Exercise during the dry period mitigated postpartal liver TG accumulation, but this did not seem to be related to increased plasma lipoprotein transport. We conclude that substantial physical activity prepartum can induce lipolysis and lipid utilization, thereby starting an early adaptation to lactation. This may be instrumental to reduce the risk for excessive liver TG accumulation postpartum, especially in cows with a high BCS at dry-off.