Effects of oil and natural or synthetic vitamin E on ruminal and milk fatty acid profiles in cows receiving a high starch diet - INRAE - Institut national de recherche pour l’agriculture, l’alimentation et l’environnement Accéder directement au contenu
Article Dans Une Revue Journal of Dairy Science Année : 2012

Effects of oil and natural or synthetic vitamin E on ruminal and milk fatty acid profiles in cows receiving a high starch diet

Résumé

Among trans fatty acids, trans-10,cis-12 CLA has negative effects on cow milk fat production and can affect human health. In high-yielding dairy cows, a shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of cows receiving high-concentrate diets, especially when the diet is supplemented with unsaturated fat sources. In some but not all experiments, vitamin E has been shown to control this shift To ascertain the effects of vitamin E on this shift of BH pathway, 2 studies were conducted. The first study explored in vitro the effects of addition of natural (RRR-alpha-tocopherol acetate) and synthetic (DL-alpha-tocopherol acetate) vitamin E. Compared with control and synthetic vitamin E, the natural form resulted in a greater trans-10 I trans-11 ratio; however, the effect was very low, suggesting that vitamin E was neither a limiting factor for rumen BH nor a modulator of the BH pathway. An in vivo study investigated the effect of natural vitamin E (RRR-alpha-tocopherol) on this shift and subsequent milk fat depression. Six rumen-fistulated lactating Holstein cows were assigned to a 2 x 2 crossover design. Cows received 20-kg DM of a control diet based on corn silage with 22% of wheat, and after 2 wk of adaptation, the diet was supplemented with 600 g of sunflower oil for 2 more weeks. During the last week of this 4-wk experimental period, cows were divided into 2 groups: an unsupplemented control group and a group receiving 11 g of RRR-alpha-tocopherol acetate per day. A trans-10 shift of ruminal BH associated with milk fat depression due to oil supplementation of a high-wheat diet was observed, but vitamin E supplementation of dairy cows did not result in a reversal toward a trans-11 BH pathway, and did not restore milk fat content.

Dates et versions

hal-02644516 , version 1 (28-05-2020)

Identifiants

Citer

Asma Zened, Annabelle Troegeler-Meynadier, Taha Najar, Francis Enjalbert. Effects of oil and natural or synthetic vitamin E on ruminal and milk fatty acid profiles in cows receiving a high starch diet. Journal of Dairy Science, 2012, 95 (10), pp.5916-5926. ⟨10.3168/jds.2012-5326⟩. ⟨hal-02644516⟩
7 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More