Effects of extruded linseed dietary supplementation on milk yield, milk quality and lipid metabolism of dairy cows
ABSTRACT Twenty Italian Friesian dairy cows were used in an experimental trial to study the effects of extruded linseed dietary supplementation on milk production, milk quality and fatty acid (FA) percentages of milk fat and total plasma lipids and plasma phospholipids. Control cows were fed a corn silage based total mixed ration (TMR) while treated animals also received 700g/head/d of extruded linseed supplementation. Feed intake was similar between groups. Milk yields was tendentially greater for cows fed extruded linseed. Milk urea content (P<0.05) were reduced by treatment. Results showed a significant increase n-3 FA concentration (particularly alpha linolenic acid) and a significant reduction of n-6/n-3 FA ratio in milk fat, total plasma lipids and plasma phospholipids (P<0.001); moreover a reduction trend (P<0.1) of arachidonic acid concentrations was observed in milk fat, total plasma lipids and plasma phospholipids. At last, treatment enhanced milk fat conjugated linoleic acid (CLA) percentage (P<0.05).
Full-textDOI: · Available from: Paolo Pezzi, Aug 24, 2015
Click to see the full-text of:
Article: Effects of extruded linseed dietary supplementation on milk yield, milk quality and lipid metabolism of dairy cows
- SourceAvailable from: Stefano Schiavon
[Show abstract] [Hide abstract]
- "In agreement with the results of the current experiment , several authors (Kennelly and Khorasani, 1992; Pezzi et al., 2007; Martin et al., 2008) reported that dietary inclusion of flaxseed did not influence the DMI "
ABSTRACT: The aim of the study was to investigate whether the addition of extruded flaxseed (EF) in dairy cow diets had an effect on milk fat and individual fatty acids (FA) recovery in cheese after 90 d of ripening. Eighteen Holstein-Friesian cows, divided into 3 experimental groups (6 cows/group), were fed 3 isonitrogenous and isoenergetic diets with 0 (CTR), 500 (EF500), or 1,000 g/d (EF1000) of EF in 3 subsequent periods (2 wk/each), following a 3 × 3 Latin square design. Dry matter intake (DMI) and milk yield were recorded daily. Individual milk samples were collected on d 7 and 13 of each period to determine proximate and FA composition. Eighteen cheese-making sessions (2 for each group and period) were carried out, using a representative pooled milk sample obtained from the 6 cows of each group (10 L). At 90 d of ripening, cheeses were analyzed for proximate and FA composition. Cheese yield was computed as the ratio between the weights of ripened cheese and processed milk. Recoveries of fat, individual FA, and grouped FA were computed as the ratio between the corresponding weights in cheese and in milk. Inclusion of EF did not affect DMI, milk yield, or milk composition. Compared with CTR, the 2 diets containing EF increased the proportion of C18:3n-3 and total n-3 FA, in both milk and cheese. Cheese yield and cheese fat percentage did not differ among diets. Likewise, milk fat recovery in cheese was comparable in the 3 treatments and averaged 0.85. The recoveries of individual FA were, for the most part, not dissimilar from fat recovery, except for short-chain saturated FA (from 0.38 for C4:0 to 0.80 for C13:0), some long-chain saturated FA (0.56 and 0.62 for C20:0 and C21:0, respectively), and for C18:3n-6 (1.65). The recovery of saturated FA was lower than that of monounsaturated FA, whereas recovery of polyunsaturated FA was intermediate. Compared with medium- and long-chain FA, short-chain FA were recovered to a smaller extent in cheese. No differences in recovery were found between n-6 and n-3 FA. In conclusion, FA have different recoveries during cheese-making, with lower values for the short-chain compared with long-chain FA, and for saturated FA compared with unsaturated FA. The addition of EF in dairy cow diets did not influence cheese yield or fat recovery in cheese, irrespective of the inclusion level. The experiment confirmed that feeding cows with EF represents a successful strategy for improving the FA profile of dairy products, through an increase of n-3 FA.Journal of Dairy Science 11/2013; 97(1). DOI:10.3168/jds.2013-7213 · 2.55 Impact Factor
[Show abstract] [Hide abstract]
- "Our results confirm that t11c15 is the major trans isomer of 18:2 produced by hydrogenation of 18:3n-3 (Chilliard et al., 2007). The EL supplementation strongly decreased the milk fat percentage of arachidonic acid, as reported by Pezzi et al. (2007), suggesting an inhibitory effect of 18:3n-3 or its metabolites on synthesis or milk secretion of this n-6 FA. "
ABSTRACT: The aim of this study was to evaluate the effects on dairy performance and milk fatty acid (FA) composition of (i) supplementation with extruded linseed (EL), (ii) supplementation with synthetic or natural antioxidants, namely vitamin E and plant extracts rich in polyphenols (PERP), (iii) cow breed (Holstein v. Montbéliarde) and (iv) time of milking (morning v. evening). After a 3-week pre-experimental period 24 lactating cows (12 Holstein and 12 Montbéliarde) were divided up into four groups of six cows: the first group received a daily control diet (diet C) based on maize silage. The second group received the same diet supplemented with EL (diet EL, fat level approximately 5% of dietary dry matter (DM)). The third group received the EL diet plus 375 IU/kg diet DM of vitamin E (diet ELE). The fourth group received the ELE diet plus 10 g/kg diet DM of a PERP mixture (diet ELEP). Compared with the diet C, feeding EL-rich diets led to lower concentrations of total saturated FA (SFA) and higher concentrations of stearic and oleic acids, each trans and cis isomer of 18:1 (except c12-18:1), non-conjugated isomers of 18:2, some isomers (c9t11-, c9c11- and t11t13-) of conjugated linoleic acid (CLA), and 18:3n-3. The vitamin E supplementation had no effect on milk yield, milk fat or protein percentage and only moderate effects on milk concentrations of FA (increase in 16:0, decreases in 18:0 and t6/7/8-18:1). The addition of PERP to vitamin E did not modify milk yield or composition and slightly altered milk FA composition (decrease in total saturated FA (SFA) and increase in monounsaturated FA (MUFA)). The minor effects of vitamin E may be partly linked to the fact that no milk fat depression occurred with the EL diet. During both periods the Holstein cows had higher milk production, milk fat and protein yields, and milk percentages of 4:0 and 18:3n-3, and lower percentages of odd-branched chain FA (OBCFA) than the Montbéliarde cows. During the experimental period the Holstein cows had lower percentages of total cis 18:1, and c9,c11-CLA, and higher percentages of 6:0, 8:0, t12-, t16/c14- and t13/14-18:1, and 18:2n-6 than Montbéliarde cows because of several significant interactions between breed and diet. Also, the total SFA percentage was higher for morning than for evening milkings, whereas those of MUFA, total cis 18:1, OBCFA and 18:2n-6 were lower. Extruded linseed supplementation had higher effect on milk FA composition than antioxidants, breed or time of milking.animal 04/2010; 4(4):627-40. DOI:10.1017/S1751731109991224 · 1.78 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: In the first of this three-part series of articles, the debate in the clinical literature over the reality or extent of particular positive health benefits of a putative nutraceutical, conjugated linoleic acids (CLAs), in human subjects was reviewed. In the second part, we explored the means by which animal scientists and farmers—responding as much to annual sales in the hundreds of millions of dollars in health food stores of seed oil capsules rich in CLAs, as opposed to any conclusive clinical science—are aggressively pursuing ways to feed livestock and fowl that would naturally increase the concentration of CLAs per conventional consumer dietary portions of beef, lamb, goat, pork, and broiler chicken meat so as to be to be marketed as functional foods. In this third and final installment, animal nutrition means of enhancing CLAs in eggs and in fluid milk, cheese, yogurts, and butter are recorded. As in the prior parts of this series, the core journals covering this third chapter in the CLA research story are identified for agricultural and food science librarians.Journal of Agricultural & Food Information 05/2009; 10(2):124-148. DOI:10.1080/10496500902802718