Annual variation in milk fatty acid composition in buffalo

The aim of this research was to monitor milk fatty acid (FA) composition over the year in severa) buffalo herds. In this paper the preliminary results obtained on a buffalo dairy farm (on average, 287 cows in milk, milk pro¬duction 7.8 kg/head/d, 8.04 % fat and 4.66 % protein) are reported. Our research lasted one year (from May to April). Weekly milk production (kg/d), number of milked animals, feed administered and refusals were record¬ed. Feed and bulk milk samples were also collected. Feeds were analysed according Weende and Van Soest. The milk samples were analysed for composition, somatic celi count and FA composition. Over the year, from September to April a standard TMR based on corn silage (St-TMR) was used. The standard ration was supplemented in May - June, by 1 kg of whole sunflower seeds (diet Su-TMR), and in July - August, by 1 kg of flaked soybeans (diet So-TMR). As expected, the addition of whole seeds substantially modified the FA profile. The concentrations of short-chain (C4:0 to C10:0)) and medium-chain (C12:0 to C16:1) FA decreased while those of long chain FA (C18:0 to C20:0) increased in the milk of cows fed St-TMR. Cows fed sunflower seed compared with soybean showed higher levels of long chain FA, especially C18:0 and C18:1 The CLA content was affected by diet, with the highest level observed for Su-TMR. Diet with sunflower seeds resulted in the lowest omega 6 to omega 3 FA ratio. The data suggest that both sunflower and soybean seed are acceptable fat sources for buffalo cows and that sunflower allows the production of milk with a healthier FA profile. Non diet related differences were also observed in FA composition. Indeed from September to April when the same St-TMR diet was used, progressive increments in medium-chain FA and saturation degree were observed. The reasons for these variations are still unclear, but DIM average, age of the herd and climate are probably involved.