1-    Effect of mixed or separate feedings and ration of Centrocema pubescens and Para grass on feed utilization, nutrient digestibility and growth performance of Crossbred rabbits

Nguyen Thi Kim Dong and Nguyen Van Thu

A study was conducted at the experimental farm and laboratory of Can Tho University to evaluate feed utilization, nutrient digestibility and growth performance of Crossbred rabbits. The experiment was a factorial design. The first factor was feeding method (Separate and mix) and second factor was ration of Centrocema pubescens and Para grass (20:80, 40:60, 60:40 and 80:20), with three replications and 4 rabbits per experimental unit. The results indicate that values of DM, CP, EE, NDF, ADF, ME intakes were significantly higher (P<0.05) in the separate feeding. The CP and EE intakes gradually increased (P<0.05) when increasing the levels of Centrocema pubescens in the diets. The digestibility coefficients of NDF and CP, nitrogen intake and retention were found significantly higher (P<0.05) for the rabbits offered separated feeds and the ration of 80:20 Centrocema pubescens and Para grass. The parameters of N-NH3 and volatite fatty acid of caecum fluid were significantly higher (P<0.05) in separate feeding and with increasing levels of Centrocema pubescens in the diets. The daily weight gain, weight of carcass, breast and thigh meat of rabbits fed separated feeds and the ration of 80:20  Centrocema pubescens and Para grass had the highest results (P<0.05).

It was concluded the separate feeding and the ration of 80: 20 Centrocema pubescens and Para grass had better growth performance and gave higher economical efficiency.

Key words: Crossbred rabbit, Centrocema pubescens, para grass, nutrient digestibility, growth performance.

2-    Effect of different size of sugar cane waste  in the basal diet with Operculina turpethum supplement on feed utilization, nutrient digestibility and growth rate of Crossbred rabbits

Nguyen Thi Kim Dong and Nguyen Van Thu

An experiment was carried out at the experimental farm and laboratory of Can Tho University to evaluate feed utilization, nutrient digestibility and growth rate of Crossbred rabbits. It was a factorial design in which the first factor was length of sugar cane waste (3 and 10 cm length) fed ad-libitum, and second factor was different supplement of Operculina turpethum (OT) (0, 100, 200 and 300g/rabbit/day) with three replications and 4 rabbits per experimental unit. The results show that the intakes of sugar cane waste were slightly higher (P>0.05) for rabbits fed 3cm length and gradually decreased with increasing supplement of OT in the diets (P<0.05), while OT intakes were remarkably increased (P<0.05). The total DM, CP, EE and ME intakes were higher for rabbits given sugar cane waste at 3cm length (P<0.05) and when increasing the levels of OT supplement (P<0.05). The digestibility coefficients of DM and CP were higher for animals offered 3cm length sugar cane waste (P<0.05), and NDF values were clearly improved with increasing OT supplement  in the diets (P<0.05). The higher nitrogen intake and retention were found for rabbits fed 3cm sugar cane waste (P<0.05) and supplemented 300g OT/rabbit/day. The daily weight gain and final live weight  were significantly higher for rabbits fed 3cm length sugar cane waste and supplemented 300g OT per animal per day (P<0.05).

It was concluded the rabbits fed 3cm length sugar cane waste and supplemented 300g OT/ animal/ day in the diet had better growth rate and gave higher economic returns.

Key words: Crossbred rabbit, Operculina turpethum, nutrient digestibility, growth rate.