English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/10545
logo share SHARE   Add this article to your Mendeley library MendeleyBASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Effect of rumen protected conjugated linoleic acid on energy metabolism of dairy cows during early to mid-lactation

AuthorsShingfield, Kevin J.; Beever, David E.; Reynolds, Christopher K.; Gulati, S. K.; Humphries, D. J.; Lupoli, Berrit; Hervás, Gonzalo ; Griinari, J. Mikko
KeywordsConjugated Linoleic Acid
Energy Metabolism
Dairy Cows
Issue Date2004
PublisherAmerican Society of Animal Science
American Dairy Science Association
CitationJoint Annual Meeting ASAS ADSA PSA. Journal of Animal Science 82(Suppl 1): 307
AbstractTrans-10, cis-12 conjugated linoleic acid (CLA) inhibits milk fat synthesis and reduces milk energy content. Controlled decreases in milk energy secretion could be used to improve energy balance of the dairy cow during early lactation. Twelve multi-parous Holstein-British Friesian cows were used in a randomized block study to evaluate the effects of rumen protected CLA (RCLA) on energy metabolism in early lactation. Supplements were prepared by casein-formaldehyde treatment of CLA methyl esters containing equal amounts of cis-9, trans-11 and trans-10, cis-12. At calving, cows were paired and allocated at random to a control diet (C) or the same diet supplemented with 110 g of RCLA that supplied 14.3 g trans-10, cis-12 CLA/d. Energy balance (MJ/d) was estimated during weeks 3, 7, 11 and 15 of lactation using 6d excreta collection and respiration calorimetry. On average, RCLA reduced milk fat content (34.9 vs. 19.2 g/kg; P<0.001) and milk fat yield (1395 vs. 901 g/d; P<0.001), increased (P<0.05) milk yield (40.3 vs. 47.4 kg/d) and milk protein output (1.25 vs. 1.42 kg/d) and tended to increase DMI (22.2 vs. 24.6 kg/d; P=0.06) and BW (614 vs. 661 kg; P=0.11). The effects on DMI and production occurred within one week of lactation. RCLA increased (P=0.08) energy intake (389 vs. 434, for C vs. RCLA, respectively), but had no effect (P>0.10) on estimated heat energy (155 vs. 169), milk energy (112 vs. 103) or energy excreted in methane (25.0 vs. 26.0), urine (11.1 vs. 11.0) or feces (108 vs. 119). However, RCLA improved (P<0.05) tissue energy balance (-17.1, 8.5, 6.6 and 24.4 at weeks 3, 7, 11 and 15 of lactation, respectively) compared with C (-53.1, -19.3, -8.2 and -6.5). In conclusion, RCLA decreased milk fat content, increased milk production and improved tissue energy balance of dairy cows during the first 15 weeks of lactation, with evidence of improved tissue N retention (19 vs. 42 g/d; P = 0.05). In contrast to the effects in growing mice, heat energy/BW.75 was not affected (1.26 vs. 1.30).
DescriptionContributed to: Joint Meeting of the American Society of Animal Science (ASAS), the American Dairy Science Association (ADSA) & the Poultry Science Association (PSA), St. Louis, Missouri, USA, Jul 25-29, 2004.
Appears in Collections:(IGM) Comunicaciones congresos
Files in This Item:
File Description SizeFormat 
Shingfield_2004-ADSA.pdf56,07 kBAdobe PDFThumbnail
Show full item record
Review this work

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