| Summary: | 碩士 === 國立宜蘭大學 === 生物技術與動物科學系動物科學碩士班 === 106 === Performance of goat kid plays an important role on maintenance of economical scale of commercial goat farm. Kid performance not only improves the quality of goat herd, but is the key of business benefits. Increase the allowance of milk can improve growth rate of goat kid. However, it increases the problem of digestive tract. Besides, the transition of intake pattern after weaning also stimulates the digestive tract of kids, which may decrease the intake and retard growth rate. Sangrovit (SGV) is a phytobiotic feed additive extracted from Macleaya cordata. It has the effect of reducing inflammation and enhancing appetite, and therefore may improve nutrient utilization and growth of animals.
Experiment 1 evaluated the effect of water-soluble SGV (SGV-WS, 0.1 g/mL milk) supplementation on growth performance and plasma characteristics by neonatal dairy goat kids (3.47 kg, SE=0.37) until age 12 weeks. Then, SGV-WS supplementation ceased, and the growth of kids was tracked for two months. It was to observe whether there were effects remained on performance and plasma traits by kids post ceased SGV-WS supplement. Four pairs of kids (n=8) born by four dams were used and kids in each pairs were allocated randomly to control and SGV-WS treatments. During the experiment, all kids received liquid milk replacer at the amount of 20% of their weekly body weight per day and began weaning at age 8 weeks. During weaning, 4% of BW was used as a unit to decrease milk allowance weekly. Weaned age depended on growth rate of kids during weaning period. Kids were weaned at age 20 weeks finally. Provision of starter concentrate and forage hay to kids began at age 9 and 16 weeks, respectively. The percentage of body weight (beginning from 0.1% of BW) to calculate feeding amount per meal. Mineral salt block and fresh water were offered ad libitum. Body weight of kids was recorded weekly for two consecutive days and values obtained were averaged. Jugular blood was collected before (0 h) and after (2 h) feeding every 4 weeks by age. The results showed that adding SGV-WS did not affect weight gain and feed-to-gain ratio of kids. However, it increased plasma globulin concentration of kids at age 4 (P<0.05) and 12 (P<0.1) weeks. After ceasation of SGV-WS supplementation, plasma globulin concentration remained higher (P<0.1) in SGV-WS group. Such results indicated that SGV-WS probably modified the immunity of kids and the effect would continue for two months after supplementation ceased.
Experiment 2 investigated the effect of Sangrovit RS (SGV-RS) supplementation on intake and nutrient utilization by growing goats. Eight dairy goats at age 7 months (28.9 kg, SE=6.1) were randomly assigned by initial body weight to metabolic cages and to the control (n=4) and SGV-RS (n=4) treatments. SGV-RS was supplemented (0.04 g/kg BW) to SGV-RS group per day by mixing with concentrate per meal. Concentrate dry matter intake was provided daily at 1.6% of body weight of goats during the experiment. Forage was fed ad libitum. The ratio of forage and concentrate was maintained between 40:60 to 60:40. Mineral salt block and fresh water were offered ad libitum. This experiment lasted for 30 days, with 23 days for adaptation and 7 days for sampling. During sampling period, daily total feces and urine were collected. Water intake of goats was recorded daily. Jugular blood was collected before (0 h) and after (2 h) morning feeding on the last day of experiment. Goats were weighted at start and end of trial period for two consecutive days and values obtained were averaged. The results indicated that intake was similar between both groups. But, adding SGV-RS increased (P<0.05) total tract dry matter and organic matter digestibility. There was no significant differences between groups in digestible nutrient intake, N intake and utilization, urine and urea N excretion, water utilization and weight gain. Goats supplemented with SGV-RS had lower (P<0.05) plasma globulin concentration, indicating that SGV-RS would also modify the immunity of growing goats.
Based on the results from thesis experiments, supplying SGV to goat kids during milk feeding period may modify the immunity of kids, and this effect could continue for two months after supplementation ceased. Supplying SGV to goat kids after weaned could also modify the immunity, with improved performance in diet digestibility.
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