The effect of supplemental n-3 fatty acids during pre- and post-partum diets on health and production of Holstein dairy cows

The aim of this experiment was evaluating effect of fish oil versus palm oil on mammary gland health and milk production in Holstein cows. Ten multiparous Holstein cows were used from six week before up to 63 days after parturition. Feed intake and milk production were recorded daily، milk composition، body weight and body condition score were measured weekly and blood metabolites were determined 21 day intervals. Milk production with fish oil consumption was increased from 6th weeks of lactation (P<0. 05). Among milk composition، only percentage and yield of milk fat were decreased in FO group (P<0. 05). Milk somatic cell count (P=0. 06) and score (P<0. 05) were decreased with fish oil consumption. Among blood metabolites، serum total cholesterol، LDL-cholesterol and LDL to HDL-cholesterol ratio were decreased in FO group (P<0. 05). Results indicated that consumption of fish oil in transition period besides conserving milk production can alleviate undesirable effects of negative energy balance in early lactation، and decrease milk somatic cell count.