Effects of Breed and Dietary Experience on Juniper Consumption by Goats

Abstract

Low nutritional quality and high levels of essential oils result in low consumption of juniper by goats. In this study we examined: (1) if juniper consumption could be increased by exposing goats to essential oils early in life; (2) if goat breeds (Spanish vs Angora) differed in juniper consumption; (3) if differences in juniper consumption were related to detoxification abilities of goats; and, (4) if differences in digestibility and nitrogen or energy balance could explain juniper consumption patterns. In the first experiment, Spanish and Angora goats 6-7 weeks old, were bolused every other day for 1 month with essential oils distilled from redberry juniper (Juniperus pinchotii Sudw.), while control animals received empty capsules. Goats were then offered redberry juniper branches in a 5-day acceptance trial. Spanish goats consumed more (1 < 0.01) juniper during the trial than Angoras. Goats previously dosed with essential oils ingested marginally less (0 < 0.086) juniper than controls. Liver-specific enzymes in blood serum (aspartate aminotransferase and gamma glutamyltransferase) were compared before and after acceptance testing to examine potential liver damage. Spanish goats apparently experienced less tissue damage in response to juniper consumption than Angora goats. A second experiment examined the digestion and metabolism of juniper. Spanish goats consumed more (0 < 0.01) juniper than Angora goats though Angoras digested juniper more completely; probably a result of their lower consumption. The metabolic fate of dietary nitrogen and energy was similar for both breeds and unaffected by exposure to essential oils early in life.