Effects Of Different Dietary Vitamin Premixs And Energy Level On Growth Performance And Meat Quality In Erlang Mountain Chicken

This study was conducted to evaluate the effects of three vitamin levels (premix 1, premix 2,premix 3) on the growth performance of Erlang Mountain Chicken. A total of 1200 broilers were randomly allotted to 3 treatments with 10 replicates (5 male and 5 female) and 40 birds per replicate. Premix 3 significantly improved the body weight gain (BWG) from 1 to 70d (P<0.05) and premix 3 significantly improved the BWG from 29 to 49d compared with premix 2 (P<0.05). Premix 3 and premix 2 tended to improve the BWG on 28 d,49 d (except premix 2) as well as feed to gain rate (FG) from 1 to 28d,29 to 49d (except premix 2),50 to 70d (P>0.05). Premix 3 or premix 2 also tended to improve the average feed intake (AFI) from 1 to 28d,29 to 49d (except premix 2),50 to 70d, and 1 to 70d (P>0.05). The BWG, AFI of male bird increased and FG of male bird decreased compared with female (P<0.05). There were no significant differences among three vitamin premixs on dead rate, carcass quality and tibia ash and bone breaking strength (P>0.05), but the carcass yield of male was heavier than female and the breast muscle of female was heavier than male(P<0.05). Premix 3 significantly reduced the serum malondialdehyde (MDA) production of 70d compared with NRC (P<0.05), the sex didn't affect the antioxidant ability of broiler. There were no interactions between vitamin premixs and sex on antioxidant activity and growth performance of Erlang Mountain Chicken (P>0.05). Results showed that antioxidant activity and growth performance of the Erlang Mountain Chicken would be improved with the increase of dietary vitamin level especially with premix 3.Experiment 2:Effects of Dietary Vitamin Premixs and Energy Level on Growth performance and Meat Quality in Erlang Mountain ChickenThis study was conducted to evaluate the effects of two energy levels (12.55MJ/kg, 10.88MJ/kg) and three vitamin levels(premix 1,2,3) on the growth performance and meat quality of Erlang mountain chicken. A total of 517 one-day-old male birds were randomly allotted to 6 treatments with 6 replicates and 16 birds per replicate. This trial was carried out as starter (1 to 28d), grower (29 to 49d) or finisher (50 to 70d).The basal diet was corn-soybean meal-rapeseed meal-wheat bran diet, birds were fed in cage and free access to feed and water. The results showed that premix 3 significantly improved the body weight gain (BWG) and decreased the feed to gain rate (FG) during 1 to 28d,1 to 70 d and 29 to 49d,1 to 70d compared with NRC and premix 2, respectively(P<0.05). Premix 3 and premix 2 significantly decreased the dead rate at 1 to 28d and 1 to 70d (P<0.05). There were no significant differences among three vitamin premixs on average feed intake (AFI)(P>0.05). High energy level significantly improved the BWG and decreased FG at each period and AFI at 29 to 49d,50 to 70d and 1 to 70 d (P<0.05), high energy level significantly improved the abdominal fat (P<0.05). Vitamin premixs and energy levels didn't affect the tibia ash content and tibia strength (P>0.05). There were no significant interactions between energy levels and vitamin premixs on growth performance, carcass quality, tibia ash content and tibia strength of broiler(P>0.05).Premix 3 significantly decreased the serum malondialdehyde(MDA) production at 28d compared with NRC(P<.05), premix 3 and premix 2 trend to decreased the serum MDA production at 49d and 70d(P>0.05). High energy level significantly decreased the serum MDA production at 28d,49d (P<0.05). There were partly interactions between energy levels and vitamin premixs on serum MDA production at 49d (.P=0.08), premix 3 in high energy diet decreased the serum MDA production to the level of low energy diet. Vitamin premixs didn't significantly affect the immune organ index, but premix 3 and premix 2 trend to increase the thymus and bursa of fabricius index(P>0.05), the low energy level significantly increased the spleen index compared with high energy level(P<0.05). Vitamin premixs didn't significantly affect the duodenal morphology(P<0.05), but premix 3 and premix 2 increased 22.8% and 2.24% of the V/Cvalue compared with NRC. High evergy level trend to increase the height of villus, V/C value and decrease the crypt depth compared with low energy level(P<0.05). There were no significant interactions between energy level and vitamin premixs on immune organ index and duodenal morphology of broiler(P>0.05).Premix 3 significantly increased the muscle glycogen of breast compared with premix 2(P<0.05), premix 3 and premix 2 trend to increase the intramuscular fat (IMF) of breast(P>0.05). Energy level didn't affect the muscle glycogen of breast (P>0.05), but high energy level significantly increase the IMF of breast compared with low energy level(P<0.05).There were no significant differences among treatments on muscle fiber and density of breast(P>0.05). Vitamin premixs didn't significantly affect the meat color of breast(P<0.05). Energy levels didn't significantly affect the L* and a* value, but high level almost significantly increased the b* value compared with low energy level (P=0.059). There were no significant interactions between energy levels and vitamin premixs on meat quality of broiler(P>0.05).Results showed that the growth performance, antioxidant activity, immunity and meat quality of the Erlang Mountain Chicken would be improved with the increase of dietary vitamin level (especially with premix 3), while high energy level improved the growth performance but also increased the oxidative stress of Erlang Mountain Chicken, while using premix 3 in high energy diet could moderate the oxidative stress.