Università di Pisa, Facoltà di Medicina Veterinaria, Dipartimento di Produzioni Animali, Viale delle Piagge, 2, 56124, Pisa, Italy.
J Dairy Res. 2010 May;77(2):239-44. doi: 10.1017/S0022029910000038. Epub 2010 Mar 3.
The aim of this study was to evaluate the milk quality of Massese ewes receiving diets with different forage:concentrate ratios (FC ratio), specially on milk fat globules characteristics and fatty acids composition. The diet is one of the main environmental factors that influence the lipidic content of milk. A trial was carried out on twenty ewes, which had been subdivided into two homogeneous groups and kept indoors at 25 days post partum. The experiment lasted 60 days, from 40 to 100 days post partum and the animals were fed two diets that differed in terms of the FC ratio: 60:40 and 40:60, as fed. The results obtained in this study showed that a greater proportion of forage, compared with an higher percentage of concentrate, led to an increase in the percentage of fat (+8.66%) and to a decrease in the percentage of milk fat globules with a size between 2 and 5 microm (-17.32%). However, the average diameter was not affected. There was also a decrease in the percentages of some medium chain fatty acids (C12:0, C14:0; -14.89% and -4.03 respectively) and an increase in mono and polyunsaturated ones such as trans11-C18:1 (+31.71%), total CLA (+22%), EPA (+18.18%) and DHA (+66.67%). In conclusion, a greater proportion of forage seem to improve the milk fatty acid profile by the increase of some fatty acid identified has being beneficial for human health.
本研究旨在评估不同饲粮精粗比（FC 比）下 Massese 母羊的产奶质量，特别是对乳脂球特性和脂肪酸组成的影响。饲粮是影响乳脂含量的主要环境因素之一。试验选择 20 只产后 25 天的绵羊，分为两组，在室内饲养。试验期为 60 天，从产后第 40 天到第 100 天，两组绵羊分别饲喂两种精粗比不同的饲粮：60:40 和 40:60。本研究结果表明，与高比例精料相比，高比例粗料使乳脂率增加（+8.66%），2-5μm 乳脂球的比例降低（-17.32%）。但平均直径不受影响。一些中链脂肪酸（C12:0、C14:0；-14.89%和-4.03%）的比例下降，单不饱和和多不饱和脂肪酸（如反式 11-C18:1、CLA、EPA 和 DHA）的比例增加，分别为+31.71%、+22%、+18.18%和+66.67%。总之，增加粗料的比例似乎可以通过增加一些对人体健康有益的脂肪酸来改善乳脂肪酸组成。
