Effects of all-milk diet on weight gain, organ development, carcass characteristics and tissue composition, including fatty acids and cholesterol contents, of growing male goats

Abstract

Effects of two dietary treatments in 16 Alpine buck kids were studied on live weight gain, organ development, carcass characteristics, free fatty acid (FFA) composition, and cholesterol content of adipose and muscle tissues. The control group (CG) was placed on a standard milk and weaning program. Milk was fed ad libitum for 4 weeks and reduced to 50% in week 5, 25% in week 7, and 0% in week 9. A solid feed (15.8% CP and 3.0 Mcal ME/kg DM) was provided ad libitum in week 5 until slaughter at week 20. The milk group (MG) was given only goat milk ad libitum for 20 weeks. Final weight and average daily gain tended to be higher ( P>0.05) for CG than MG. Weights of liver, lung, rumen, reticulum, and omasum were lower ( P<0.01) and cecum weight was higher ( P<0.05) in MG kids. Leg conformation score ( P<0.01), overall conformation score ( P<0.01) and lean maturity ( P<0.05) were higher for CG. Content of unsaturated fatty acids (UFA)( P<0.01) and polyunsaturated (PUFA) fatty acids 9 P<0.001) were higher in tissues of CG than in those of MG, reflecting higher percentages of oleic and linoleic acids observed in CG tissues. Oleic acid was the most abundant in CG, whereas palmitic acid was the most abundant in MG tissues. Muscle cholesterol was lower ( P<0.05) in CG (75.9 mg/100 g) than in MG (101.5 mg/100 g). Goat meat from CG kids contained higher PUFA to SFA ratios.