Effects of Hybrid Pennisetum Forage Supplemented with Rumen-protected Methionine on Growth and Nutrient Digestion of Fuqing Goats

  Objective  Effects of feeding hybrid pennisetum forage supplemented with rumen-protected methionine (RPMet) on the growth and nutrient digestion and metabolism of Fuqing goat were studied.

  Method  Thirty 4-month-old, 11.88±1.48 kg Fuqing goats from a same batch of estrus synchronization were randomly divided into 5 groups of 6 goats in each group. The feeding experiment including basic diet (CK) and an addition of RPMet at 2.5 g·d⁻¹ (Group Ⅰ), 5.0 g·d⁻¹ (Group Ⅱ), 7.5 g·d⁻¹ (Group Ⅲ), or 10 g·d⁻¹ (Group Ⅳ) started after a pre-testing period of 15 d to last for 60 d. In the middle of the feeding period, 3 goats were randomly selected from each group to determine the apparent nutrient digestion and nitrogen metabolism of the animals.

  Result  (1) No significant differences in DMI, IBW, and FBW were found among all groups (P＞0.05). The total weight gain and ADG of Group Ⅰ and Group Ⅱ were significantly higher than those of control (P＜0.05), but not on those of Group Ⅲ and Group Ⅳ (P＞0.05). (2) The apparent digestions of DM, OM, GE, NDF, ADF, and CP by the goats in Group Ⅱ were the highest. Those of GE, CP, and ADF were significantly higher in Group Ⅱ than in other groups (P＜0.05), those of DM and OM significantly higher than in Group Ⅲ and Group Ⅳ or control (P＜0.05), and that of NDF significantly higher than in Group Ⅲ and Group Ⅳ (P＜0.05). (3) The nitrogen intake of the goats in the control group was significantly lower than that of the treatment groups (P＜0.05). The urine and fecal nitrogen in goats of Group Ⅰ and Group Ⅱ were not significantly different from those of control (P＞0.05), but significantly higher than those of other test groups (P＜0.05). Group Ⅰ and Group Ⅱ animals also had significantly higher nitrogen deposition and deposition rate than those of other groups (P＜0.05). The biological value of nitrogen of the goats in Group Ⅰ was the highest and significantly higher than that in Group Ⅲ, Group Ⅳ, and control (P＜0.05), while Group Ⅳ was significantly lower than control (P＜0.05).

  Conclusion  The supplementation of RPMet at a rate of 2.5～5.0 g·d⁻¹ in the hybrid pennisetum forage benefited nutrient digestion and utilization of the Fuqing goats which promoted fattening before slaughtering.