Effects of mineral supplementation on the performance of nulliparous and multiparous does fed forage containing diets

Abstract Text: The effect of the mineral supplementation on the performance of nulliparous and multiparous rabbit does fed forage containing diets was evaluated in 18 rabbit does crossed New Zealand and Russian californian with an average live weight 3.65 ± 0.15 kg, placed in individual cages, distributed following a complete randomized design with factorial arrangement 2x3, with two levels of parity (PA), multiparous (M) and nulliparous (N), and three levels in salt supplementation (S), without salt (NS), with 6% P (S6), 11.4% Ca y 6% P, and 8% P (S8), 15.2% Ca y 8% P, with three replications. The diet consisted of 85% of commercial feed and 15% trichantera forage based in DMI (Mineral composition: 1.4% Ca and 0.56% P). Salts was formulated to keep a constant calcium:phosphorus ratio and levels of trace minerals. The salt was offered in plastic licks from 15 d before mating to weaning. Lactation period was 30 d. To rabbit does performance was evaluated farrowing weight, weaning weight and DMI. In the performance of kits the litter size at birth, at weaning and weight gain in lactation was evaluated. Data were analyzed in module GLM of SAS ver. 9.2. Analysis of covariance to the initial weight of the rabbit does and comparison of means by orthogonal contrasts was performed. The performance of kits was not affected (P>0.05). In rabbit does performance no interaction between S and PA was observed (P>0.05). There were no differences (P>0.05) between groups for DMI, 101.1, 107.7, 109.9, 101.0, 107.8 and 103.0 g/d of DMI to N-NS, N-S6, N-S8, M-NS, M-S6 and M-S8, respectively and 0.42, 0.37, 0.38 and 0.34 g/d of sal to N-S6, N-S8, M-S6 and M-S8, respectively. The farrowing weight of rabbit does was higher (P<0.01) in S8 compared to S6, 3841 and 3388 g to S8 and S6, respectively. S8 increase (P<0.05) the weaning weight of the rabbit does relative to S6, 4055 and 3608 g to S8 and S6, respectively. In conclusion, supplementation with salt 8% P improves the performance of rabbit does fed forage containing diets, but not affect the performance of the litter. 

Keywords: Phosphorus, Rabbit Does, Salt