Effects of different ascorbic acid supplement levels on growth rate, nutrients digestibility and economic return of crossbred rabbits in the Mekong delta of Viet Nam
A study was conducted to evaluate the effects of different ascorbic acid supplement levels in the diets on growth performance, nutrients digestibility and economic return of growing crossbred (New Zealand White x local) rabbits. Sixty rabbits at 42 days of age were arranged in a completely randomized block design with 5 treatments and 3 replications. Four rabbits including 2 males and 2 females were in one experimental unit. Five treatments were 5 ascorbic acid levels adding to drinking water at 0, 250, 500, 750 and 1000 mg per one litter, corresponding to C0, C250, C500, C750 and C1000 treatments, respectively. The apparent nutrient digestibility and nitrogen retention of the rabbits were measured at 12 weeks of age in 7 days. This experimental period was 12 weeks. The results of the study showed that DM, CP and ME intakes were significantly different (P<0.05) among the treatments with the higher values for C500 treatments. The daily weight gain was significantly different (P<0.05) among treatments and it was 19.4, 20.2, 21.7, 18.2 and 18.0 g/day for C0, C250, C500, C750 and C1000 treatments, respectively. The profit was the highest for C500 treatment. The nutrients digestibility was significantly higher (P<0.05) for C500 treatment. It could be concluded that adding ascorbic acid to drinking water at 500 mg per litter should be used to feed growing crossbred rabbits for improving growth, digestible nutrients and economic return.
