Growth performance, nutrient digestibility, carcass traits, body composition, and meat quality of goat fed Chinese jujube (Ziziphus Jujuba Mill) fruit as a replacement for maize in diet

Abstract

This study was conducted to evaluate the effect of Chinese jujube meal replacement for maize in ration on the growth performance, digestibility coefficient, carcass traits, body composition and meat quality in Jinlan cashmere goats. Thirty approximately 14-months-old male Jinlan cashmere goats with similar body weight (25.00 ± 1.53 kg) were randomly assigned to five groups in a completely randomized design. Five levels of jujube meal were formulated in the ration, in which maize was replaced by different levels of jujube meal 0 (C), 50 (J5), 100 (J10), 150 (J15), 200 (J20) g/kg dietary dry matter (DM). The experimental period lasted 50 days: 10 days for adaption and 40 days for measurements. The results showed that goats in J15 had higher dry matter intake (DMI) and average daily gain (ADG) compared with C group, which had a lower feed convention ratio (FCR, g DMI/g ADG) than that in C group (P < 0.05). The increase of jujube replacement in the ration enhanced the digestibility coefficients of DM, organic matter (OM) and crude protein (CP) in a linear, quadratic and cubic manner (P < 0.05), and acid detergent fiber (ADF) in a quadratic and cubic manner (P < 0.05). Dressing percentage and meat weight were higher in J15 than those of C group (P < 0.05). Animals fed the jujube diets had a higher rumen ratio than those in C group (P < 0.05). Warner-bratzler shear force (WBSF) and pH in longissimus dorsi (LD) declined in quadratic and cubic manner with supplementation of jujube meal (P < 0.05). There was no effect of jujube meal on moisture and ash contents of LD muscle (P > 0.05). Ether extract (EE) content in LD muscle was significantly lower, whereas protein content was significantly higher in treatment groups than in C group (P < 0.05). Substitution of jujube meal for maize stimulated the accumulation of Ca, K, Mg Na and Fe in LD muscle of J15 group in comparison with that in C group. The results of the non-essential amino acids (NEEA) composition of LD muscle were similar for all groups except histidine. Diet in J15 and J20 stimulated the accumulation of valine, isoleucine, leucine, C18:0 and C18:2n-6 cis (P < 0.05) in LD muscle. In conclusion, our study suggests that jujube meal, at concentration up to 150 g/kg dietary DM, is considered as an optimal alternative feed resource for maize as it promotes growth performance, improves meat quality and composition.