We investigated the effect of glutathione supplementation on feed intake, body weight loss, behavior change and economic analysis of elk bull in breeding season. Sixteen elk bulls (5-year-old, average weight; 330 kg) after antler cutting were divided into 2 groups. Eight bulls in each group (control and glutathione group) were fed experimental diet at a level of 0.85 percent of body weight and 6 mg glutathione per kg body weight. As a result, weight-loss of control animal during experimental study (from September to November) was 42.6±19.2 kg while that of glutathione-supplemented group was 20.6 ±19.9 kg. Compared to control group, glutathione-fed group had prevented the body weight loss by 5.2% (p<0.05). Although the feed intake of elk voluntarily decreases during breeding season, daily DM intake per head was 5.59 and 5.80kg in control and glutathione-fed group, respectively. While the statistical difference in feed intake between two groups was not observed, feed intake tended to increase in glutathione-fed group. In economic analysis, additional cost of 99,000 KRW per head was spent due to the cost of glutathione because of its import. Changes in behavior such as crying, deer whistles, whistling intensity and frequency of accident were lower in glutathione-fed group compared to control. During breeding season, use of glutathione as feed supplement could suppress body weight loss and accidents in deer farm.

We investigated the effect of glutathione supplementation on body weight gain, feed intake, velvet antler yield and economic analysis in elk bulls. A total 14, 2-year old male elks were divided into 2 groups with control or glutathione treatment. Elks were fed concentrate feed at the level of 1.5% relative to body weight (3.1 kg). and allowed to consumed hay as roughage ad libitum. Glutathione was supplemented at the level of 6 mg/kg. Average daily gains (ADG) for 2-years old elks were 234.1± 7 and 247.6±22 kg in control and glutathione fed groups, respectively. Treated group had higher ADG than control (p<0.05). Individual daily DM intakes were 5.34±0.70 and 5.64±0.71 kg in control and glutathione supplemented groups, respectively. Glutathione-fed group showed an additional intake of 298 g on an average. Production of velvet antlers for elk yearlings was 4,229±720 g and 4,653±960 g in control and glutathione supplemented groups respectively. Analysis of economics efficiency revealed 8% higher revenue index in glutathione supplemented groups. In conclusion, glutathione supplementation showed increase of DM intake and ADG in elk bulls, and could also increase velvet antler production.

We investigated the effect of glutathione supplementation on feed intake, body weight gain, velvet antler yields and economics of elk yearling. Fourteen elk yearlings were divided into 2 groups. Seven yearlings in each group (control and treatment) were fed with 1.5-2.5 percent body weight (%BW) of concentrate feed for elk, voluntary intake of hay as roughage and 6 mg/kg body weight (KBW) of glutathione. The results were as follows. Average daily gain (ADG) for control elk yearlings for first 1.5 month was 0.46 kg, while that of glutathione supplemented was 0.55 kg. Although glutathione fed group had higher ADG compared to control group (p<0.05), ADG after 1.5 month showed no difference. In spring, daily DM intake per elk yearlings was 3.98 and 4.24 kg for control and glutathione supplemented groups, respectively. The statistical differences in feed intake between two groups were not observed. However, feed intake tends to increase in glutathione fed group. Production of velvet antlers for elk yearlings were 911±256 and 1066±357 g for control and glutathione supplemented groups, respectively. Statistical difference between two groups was not observed due to the high variation. In economic analysis, additional 109,110 KRW per head for the cost of glutathione resulted in 2 percent higher revenue index due to the increased antler production. In conclusion, feeding glutathione to elk deers effectively increased DM intake and ADG of elk yearlings. Glutathione supplementation in feed might increase velvet antler production as well as ADG.