Cobalt reduces the Δ 9-desaturase index of sow milk

Abstract

The main objective of this study was to examine if cobalt (Co) reduces Δ 9-desaturase indices in milk and blood lipids in sows. The experimental design consisted of a repeated measurement consisting of a pre-treatment period of a minimum of 9days, a treatment period of 5days and a post-treatment period of 6days. Experimental animals consisted of 10 lactating sows; five sows had an intramuscular injection of 59mg Co diluted in 5ml 0.9% saline solution twice a day, whereas the other five had an intramuscular injection of 5ml 0.9% saline solution twice a day as a control. Milk Δ 9-desaturase indices for cis-9 18:1, cis-9 16:1 and cis-9 14:1 were significantly reduced (p<0.0001) as a result of the Co-treatment, contrasting with the plasma Δ 9-desaturase indices, which were unaffected. Potential mechanisms explaining how Co might reduce milk Δ 9-desaturase indices are discussed. Moreover, the toxicological level of Co and potential implications of using Co-ethylenediaminetetraacetic acid as a liquid marker in digestibility experiments are addressed. © 2010 Blackwell Verlag GmbH.