Substitution of Concentrate by Protein Source Forage for Growing Heifer of Friesian Holstein (FH)

Abstract

The best weight of Friesian Holstein (FH) heifer used for replacement stock at rst matting is above 300 kg at 15 months old. To achieve that weight, the animals must at least grow for 600-700 g/day after weaning period (11 months of age). High quality diet is required to maintain the high growth rate. Leguminous leaves, Gliricidia sepium is high protein sources feed contains amino acids that can support high growth rate as well as development of female reproductive organs. A study was undertaken to investigate the effect of concentrate subtitution by Gliricidia leaves on performance of young FH heifer. Three Rations with similar metabolize energy level of 11 MJ/kg, were investigated by using Complete Block Design. Ration A: King grass (RR)+consentrate(Con); Ration B: RR+Con+Gliricidia (L1=16%) and Ration C: RR+Con+Gliricidia(L2=31%). The study measured feed intake, body weight gain for 5 months, blood metabolite concentration, and progesterone concentration pro le. Results indicated that growth rate of animals in three groups were below the body weight gain targeted in the beginning of experiment. At 15 months old, the weight of heifers fed Ration A was 272 kg; Ration B was 270 kg and Ration C was 255 kg. Plasma urea and glucosa concentration in animals fed Ration A were lower (9.8 mg/dl and 70.4 mg/dl) than those of animals fed Ration B (10.98 mg/dl and 71.1 mg/dl) and Ration C (11.13 mg/dl and 72.4 mg/dl) (P>0.05). The concentratrion of progesteron at a peak was 11.6 ng/ml; 12.71 ng/ml and 11.71 ng/ml for animals in group Rations A, B and C, respectively (P>0.05). It is concluded that subtitution of concentrate by Gliricidia leaves up to 31% has no negative effect on intake, urea and glucose concentration and progesterone concentration pro le, but affected the live weight gain of young heifer FH.