盲肠灌注不同SCFA对驴乳生产性能及乳脂肪酸组成的影响

Effects of Cecal Infusion of Different SCFA on Donkey Milk Performance and Milk Fatty Acid Profile

旨在了解驴盲肠发酵产物对乳成分合成的影响。本研究选择4头安装永久盲肠瘘管的泌乳母驴(体重(182±9)kg),在泌乳晚期((155±15)d),经盲肠用连续灌注法,采用4×4拉丁方设计,连续3h灌注3种不同比例和组合的短链脂肪酸(SCFA):乙丙组(乙酸150mmol·h^(-1)+丙酸50mmol·h^(-1))、乙丁组(乙酸170mmol·h^(-1)+丁酸30mmol·h^(-1))、乙丙丁组(乙酸130mmol·h^(-1)+丙酸50mmol·h^(-1)+丁酸20mmol·h^(-1)),对照组灌注相同体积的缓冲液。结果发现,不同处理组间乳产量无显著差异(P>0.10)。乙丁组乳脂、非脂固形物、乳糖和乳蛋白含量均显著高于乙丙丁组(P<0.10);乙丙和乙丁组中乳蛋白含量显著高于乙丙丁组(P<0.10),其余各指标差异不显著(P>0.10)。乙丙和乙丙丁组的中链脂肪酸比例显著高于对照组(P<0.05),乙丙、乙丁和乙丙丁组长链脂肪酸比例显著低于对照组(P<0.05)。结果显示,经盲肠灌注乙酸和丁酸有助于提高乳成分含量,灌注乙酸和丙酸有利于增加乳脂的中链脂肪酸比例,盲肠SCFA参与并影响驴乳脂合成。

To investigate the effects of cecal fermentation products on donkey milk synthesis,4donkeys installed permanently cecal fistula were selected（body weight（182±9）kg）at late lactation stage（（155±15）d）.Through continuous infusion method via cecum,using 4×4 Latin square design,3different proportions and combinations of short chain fatty acids（SCFA）were continuous infused for 3h：AP group（acetic acid of 150 mmol·h^（-1）＋ propionic acid of 50mmol·h^（-1））,AB group（acetic acid of 170 mmol·h^（-1）＋ butyric acid of 30 mmol·h^（-1））,APB group（acetic acid of 130 mmol·h^（-1）＋ propionic acid of 50 mmol·h^（-1）＋ butyric acid of 20mmol·h^（-1））,and the control group was perfused equivalent volume of buffer solution,to study the effects of different compositions and proportions of SCFA on donkey milk production and milk fatty acids.The results showed that there was no significant difference（P 〈0.10）in milk yield among different treatments.Milk fat,non-fat solid,lactose and protein contents were significantlyhigher in AB group than in APB group（P 〈0.10）;In AP and AB groups,milk protein contents were significantly higher than that in the APB group（P 〈0.10）,the other indices of milk constituents showed no significant difference among different groups（P 〉0.10）.Compared to control group,percent of middle-chain fatty acids in AP and APB groups were significantly increased（P 〈0.05）,while percent of the long-chain fatty acids in AP,AB and APB groups were lower than that in control group（P〈0.05）.It was concluded that infusion of acetic and butyric acids through cecum helped to improve contents of milk constituents,and infusion of acetic and propionic acids increased percent of middle-chain fatty acids of milk fat,SCFAs from cecum directly affected donkey milk synthesis.