Milk and Cheese Fatty Acid Composition in Sheep Fed Mediterranean Forages with Reference to Conjugated Linoleic Acid cis-9,trans-11

Abstract

Two experiments were undertaken to evaluate the effect on milk and cheese fatty acid composition of feeding different fresh forages to dairy sheep both in winter (experiment 1, growing stage of the forages, early lactating ewes) and in spring (experiment 2, reproduction stage of the forages, midlactating ewes). Four forage species were compared: annual ryegrass (RY, Lolium rigidum Gaudin), sulla (SU, Hedysarum coronarium L.), burr medic (BM, Medicago polymorpha L.), and a daisy forb (CH, Chrysanthemum coronarium L.). The forages were cut twice daily and offered ad libitum to 4 replicate groups of Sarda dairy sheep (groups RY, SU, BM, and CH). The CH forage was particularly rich in linoleic acid in both periods, whereas BM and SU forages were rich in linolenic acid in winter and spring, respectively. Milk fatty acid composition was affected by the forage in both experiments. Milk conjugated linoleic acid and vaccenic acid contents were higher in CH and BM groups (winter) and CH group (spring) than in the other groups. No differences were observed when comparing fatty acid profile between milk, 1-d-old cheeses, and 60-d-old cheeses within experimental groups, suggesting that the fatty acid recovery rates during cheese making and ripening were not affected by the feeding regimens. After stepwise discriminant analyses of the pooled data, the milks and cheeses sourced in the different feeding regimens differed among them. Based on these results, we conclude that it is possible to manipulate the fatty acid profile of sheep dairy produce to maximize the content of beneficial fatty acids by the use of appropriate fresh forage-based regimens.

Fatty acid composition of muscle and internal fat depots of organic and conventional Payoya goat kids

“…Except for pelvic fat, in this study there were no significant differences between the atherogenicity index in goat kid from organic or conventional managed dams. There are no known values of this index in studies of goats, nevertheless, the index values for both groups were lower that those reported in milk of sheep fed Mediterranean forages (Addis et al, 2005). The low fat content and FA profile (especially the PUFA content and the n-6:n-3 PUFA ratio) of meat from kids reared in both production systems indicates the beneficial characteristics of this meat with respect to human health.…”

Effects of a dairy product (pecorino cheese) naturally rich in cis-9, trans-11 conjugated linoleic acid on lipid, inflammatory and haemorheological variables: A dietary intervention study

“…Actually, sheep cheese is naturally rich in CLA because it is made with milk from grazing ewes. In fact, it is well known from the literature that it is possible to manipulate the fatty acid profile of sheep dairy products, in a higher extent than that of the cows, to maximize the content of beneficial fatty acids by the use of appropriate fresh forage-based regimens [13]. CLA has been recently reported to have antiatherogenic and antineoplastic properties [4e6].…”

Effects of a tannin-rich legume (Onobrychis viciifolia) on in vitro ruminal biohydrogenation and fermentation

“…In any case, responses at both time points may be attributed to the effect of sainfoin on ruminal lipid metabolism, given that the inhibition of trans C18 saturation would accumulate vaccenic acid and trans-11 cis-15 18:2, but a negative influence on the first BH steps would decrease their production. This latter response, linked to a lower or slower disappearance of dietary PUFA, appears to better reflect the in vivo effects reported for other tannin-rich legumes, such as the lower milk proportion of trans-11 18:1 and cis-9 trans-11 CLA together with increases in 18:3n-3 and 18:2n-6 in ewes fed sulla (Addis et al, 2005;Cabiddu et al, 2009). In line with this, Turner et al (2005) pointed toward a general inhibition of BH, and not only on the last step, when examining the effects of Lotus corniculatus in- Sainfoin, fatty acid biohydrogenation and ruminal fermentation tation and compromise its practical application in ruminant feeding.…”