Fatty acid composition and milk quality related to feeding Ca-saponified palm acid oil to different breeds of dairy cows

Abstract

SummaryThe effect of supplementing a normal dairy feed ration (3–4% fatty acid of DM) with saponified palm acid oil (soap) was investigated in two experiments. The first experiment was carried out in eight herds (four Jersey, four heavy breeds), where the diet was supplemented with 1·0 and 0·5 kg soap for cows in the first and last part of lactation, respectively. Taste and acid degree of milk were not affected, and no breed × soap interaction was found. Fatty acid composition in milk was only slightly but significantly affected. The content of short and medium chain fatty acids was reduced (3·5% unit) and was followed by an increase in the content of 16:0 and 18:1. The increase in 16:0 by the soap supplementation was smaller in Jersey cows than in the other breeds. In the second experiment the effect of supplementing diets either with 0·5 or 1·0 kg Ca-soap to cows in the first part of lactation was investigated in two herds of Danish Black and White cows. Acid degree and time for curd formation on renneting (K20) were significantly lowest at the highest soap inclusion. No general effect on the proportion of short and medium chain fatty acids in the milk fat was observed as a function of level of Ca-soap, but the proportion of 16:0 was increased. It is assumed that the very small effect on milk fatty acid composition obtained when the daily allowance of fatty acids was increased from 600 to ~ 1400 g per cow, is more or less a specific effect of dietary fat rich in palmitic acid and given in excess to the basic diet.