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为了研究脂肪酸的含量、种类及变化规律,试验采用气相色谱-质谱法对20头牦牛在哺乳期内(1~180 d)12个时间点的乳样进行了分析测定。结果表明:在牦牛乳样内共检测出30余种脂肪酸,其中含量最高的为十六烷酸即软脂酸/棕榈酸,其次为十八碳烯酸,含量最低的是十三碳酸和全顺式-5,8,11,14-二十碳四烯酸即花生四烯酸。相对产犊后第15天而言,长链脂肪酸在整个哺乳期无显著差异;中链脂肪酸在产犊后3~7天及120天与其他时间点相比有显著差异(P<0.05);单不饱和脂肪酸则在产犊后第3,4天有显著差异,在5,6,7天有极显著差异(P<0.01);而多不饱和脂肪酸仅在120天与其他时间点有显著差异。
In order to study the content, types and variation of fatty acids, the milk samples of 20 yaks during lactation (1 ~ 180 d) were analyzed by gas chromatography-mass spectrometry at 12 time points. The results showed that more than 30 kinds of fatty acids were detected in milk samples of yak, among which palmitate was palmitic acid, palmitic acid was the highest, octadecenoic acid was the next, and tridecanoic acid was the lowest. -5,8,11,14 - arachidonic acid that arachidonic acid. Relative to the 15th day after calving, there was no significant difference in long chain fatty acids during the whole lactation period. There was a significant difference (P <0.05) in medium chain fatty acids between 3 and 7 days and 120 days after calving compared with other time points. The monounsaturated fatty acids showed significant difference on the 3rd and 4th days after calving, and there was a significant difference on the 5th, 6th and 7th days (P <0.01), while the PUFAs were significant at 120 days and at other time points difference.