English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/22710
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

Milk fatty acid profile and dairy sheep performance in response to diet supplementation with sunflower oil plus incremental levels of marine algae

AuthorsToral, Pablo G. ; Hervás, Gonzalo ; Gómez-Cortés, Pilar ; Frutos, Pilar ; Juárez, Manuela ; Fuente, Miguel Ángel de la
KeywordsCLA
Milk fat depression
ω-3
Trans fatty acid
Issue Date2010
PublisherAmerican Dairy Science Association
CitationJournal of Dairy Science 93: 1655-1667 (2010)
AbstractIn an attempt to develop strategies for enhancing the nutritional value of sheep milk fat, dairy ewe diet was supplemented with three incremental levels of marine algae (MA), in combination with sunflower oil, to evaluate the effects of these marine lipids on milk fatty acid (FA) profile and animal performance. Fifty Assaf ewes in mid-lactation were distributed in 10 lots of 5 animals each, and allocated to 5 treatments (2 lots per treatment): non-lipid supplementation (Control), or supplementation with 25 g of sunflower oil/kg DM plus 0 (SO), 8 (SOMA1), 16 (SOMA2), or 24 (SOMA3) g of MA (56.7 % ether extract)/kg DM. Milk production and composition, including FA profile, were analysed on days 0, 3, 7, 14, 21 and 28 on treatments. Neither intake nor milk yield were significantly affected by lipid addition but all MA supplements decreased milk fat content from d 14 onward, reaching a 30% reduction after 28 d on SOMA3. This milk fat depression might be related not only to the joint action of some putative fat synthesis inhibitors, such as trans-9 cis-11 C18:2 and probably trans-10 C18:1, but also to the limited ability of the mammary gland to maintain a desirable milk fat fluidity, that would have been caused by the noticeable rise in trans-C18:1 together with the lowered availability of stearic acid for oleic acid synthesis through the delta-9 desaturase. Furthermore, all lipid supplements, and mainly MA, reduced the secretion of de novo FA (C6:0-C14:0) without increasing the yield of pre-formed FA (> C16). SOMA supplementation resulted in larger increases in RA (cis-9 trans-11 C18:2) than those observed with SO alone, achieving a mean content as high as 3.22% of total FA, and representing more than a 7-fold increase compared to the control. Vaccenic acid (trans-11 C18:1) was also significantly enhanced (on average +794% in SOMA treatments), as was C22:6 ω-3 (DHA) content, although the transfer efficiency of the latter, from the diets to the milk, was very low (5%). All the same, the highest levels of MA inclusion (SOMA2 and SOMA3) reduced the milk ω-6/ω-3 ratio. On the other hand, MA supplements caused an important increase in trans-10 C18:1, which would disallow from considering that this milk has a healthier fat profile before unravelling the specific role of each individual FA and ensuring that this trans-FA is at least innocuous in relation to the cardiovascular disease risk.
Description13 pages, 3 figures, 4 tables.
Publisher version (URL)http://jds.fass.org/
http://dx.doi.org/10.3168/jds.2009-2769
URIhttp://hdl.handle.net/10261/22710
DOI10.3168/jds.2009-2769
ISSN0022-0302
Appears in Collections:(IGM) Artículos
(IF) Artículos
Files in This Item:
There are no files associated with this item.
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.