Effect of energetic supplementation with coco-nut oil to lactating mares diets on blood and milk composition

Abstract

The effect of dietary supplementation with coconut oil (CO) with four levels (0, 4, 8 and 16%) on the variation of blood and milk composition of lactating mares were investigated. Sixteen lactating mares were used with average live weight of 441.2 kg. Mares were supplemented with 1,5% of live weight with concentrate composed of corn meal, wheat bran and soybean meal with 16% crude protein. Forage was Napier grass and mineral supplement and water supplied "ad libitum". Mares were allotted to 16 pens (4x5m) and randomly assigned to receive each of four diets once a day during 42 days. Samples of blood (50 ml) were collected for analysis of triglycerides and cholesterol. Samples of milk (250 ml) were collected manually for analyses of acidity, fat and cholesterol. At the end of the experiment the supplementation with CO showed respectively for blood: triglycerides, 24; 32; 28 and 25 mg dl-1; cholesterol, 107; 136; 126 and 129 mg dl-1 and for milk: acidity, 10; 9; 8 and 7 ºD; fat, 0,6; 1,1; 0,9 and 0,9%. Cholesterol in the fat of the milk, 366.5; 308.6; 447.9 and 491.0 mg.100g-1. The supplementation with CO, increased the triglycerides levels and plasmatic cholesterol, with linear effect; they reduced the level of acidity and increased fat content of milk with linear effect and they had no effect on cholesterol content in the milk.