Effect of dietary supplementation with flavonoid from Scutellaria baicalensis Georgi on growth performance,meat quality and antioxidative ability of broilers

An experiment was conducted to investigate the effect of dietary supplementation with flavonoid from Scutellaria baicalensis Georgi（SBGFN） as SBGFN-zinc（SBGFN-Zn） on growth performance, meat quality, immune responses and antioxidation of broilers. A total of 450 one-d-old Arbor Acres male broilers were randomly allocated to 5 treatments with 6 replicates of 15 birds per replicate for each treatment in a completely randomized design. Birds were fed a SBGFN-unsupplemented cornsoybean meal basal diet（control） or the basal diet supplemented with 60, 120, 180 or 240 mg SBGFN kg-（–1） from SBGFN-Zn for 42 d. Dietary SBGFN supplementation affected（P〈0.03） drip loss in thigh muscle, total superoxide dismutase（T-SOD） and glutathione peroxidase（GSH-Px） activity in liver of broilers at 42 d of age. Chicks fed the diets supplemented with 120, 180 and 240 mg SBGFN kg-（–1） had lower（P〈0.03） drip loss of thigh muscle than those fed the control diet. Chicks fed the diet supplemented with 180 mg SBGFN kg-（–1） had higher（P〈0.03） liver T-SOD and GSH-Px activity than those fed the diets supplemented with 0, 60 and 120 mg SBGFN kg-（–1）. The results from the present study indicate that dietary supplementation with 180 mg SBGFN kg-（–1） as SBGFN-Zn improved both meat quality and antioxidative ability of broilers.

Effects of Different Dietary Energy and Protein Levels on Meat Performance and Meat Quality of Jinghai Yellow Chickens

To investigate the effect of different dietary energy and protein levels on meat performance and meat quality of Jinghai yellow chickens, 480 43-day old Jinghai yellow chickens with similar weight were randomly divided into four experimental groups： experimental group 1 （protein 15%, metabolic energy 9.95 MJ/kg）, experimental group 2 （protein 16%, metabolic energy 10.95 MJ/kg）, experimental group 3 （protein 17%, metabolic energy 12.65 MJ/kg） and experimental group 4 （ protein 18%, metabolic energy 13.95 MJ/kg）, respectively. All chickens were slaughtered at 112-day old. The breast and leg muscles of Jinghai yellow chickens were collected, to determine the slaughter performance, conventional meat quality and muscle chemical indicators. The results indicated that dressing-out percentage and eviscerated yield percentage in four experimental groups were above 87.27% and 67.00%, respectively; other slaughter performance indicators exhibited no significant differences among various groups （P 〉 0.05 ） ; breast muscle color of hens in experimental group 4 varied significantly from that in other three groups （ P 〈 0.05 ） ; leg muscle color of hens in experimental group 2 varied extremely significantly from that in other three groups （ P 〈 0.01 ） ; water-holding capacity of breast muscles of hens in experimental group 3 was significantly higher than that in experimental group 4 （P 〈 0.05 ） ; thiamine content of breast muscles of cocks in experimental group 3 was significandy higher than that in experimental group 2 （ P 〈 0.05 ） ; however, other properties exhibited no significant differenees among various groups （P 〉 0.05 ）.

Effects of different dietary energy and protein levels and sex on growth performance,carcass characteristics and meat quality of F1 Angus x Chinese Xiangxi yellow cattle

Background：The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods：During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a2×2×2 factorial arrangement under two levels of- dietary energy（TON：70/80%DM）,protein（CP：11.9/14.3%DM）and sex（S：male/female） during the finishing phase of 146 d.The treatments were-（1） high energy/low protein（HELP）,（2） high energy/high protein（HEHP）,（3） low energy/low protein（LELP） and（4） low energy/high protein（LEHP）.Each treatment used 6 steers and 6 heifers,except for HELP- 5 steers and 6 heifers.Results：Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex.Compared with the LE diet group,the HE group had significantly lower dry matter intake（DMI,6.76 vs.7.48 kg DM/d）,greater chest girth increments（46.1 vs.36.8 cm）,higher carcass fat（19.9 vs.16.3%） and intramuscular fat content（29.9 vs.22.8%DM）.The HE group also had improved yields of top and medium top grade commercial meat cuts（39.9 vs.36.5%）.The dressing percentage was higher for the HP group than the LP group（53.4 vs.54.9%）.Steers had a greater length increment（9.0 vs.8.3 cm）,but lower carcass fat content（16.8 vs.19.4%） than heifers.The meat quality traits（shear force value,drip loss,cooking loss and water holding capacity） were not affected by treatments or sex,averaging 3.14 kg,2.5,31.5 and 52.9%,respectively.The nutritive profiles（both fatty and amino acid composition） were not influenced by the energy or protein levels or by sex.Conclusions：The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance,meat quality traits and nutritive profiles.

Effects of Non-starch Polysaccharide Enzyme Products on Meat Performance in Broilers

[ Objective] To investigate the effects of non-starch polysaccharide （NSP） enzyme products on meat performance of broilers and thus to provide a scientific basis for their rational use. [Method] Two hundred 21-day-old Ross broilers were assigned to five groups. The broilers in group Ⅰ and group Ⅱ were fed positive control diet and negative control diet, respectively, which were slightly different. The broilers in group Ⅲ, Ⅳ and V were fed the negative control diet respectively supplemented with different commercial NSP enzyme products. The broilers were slaughtered at 56 days old, and their meat yield was determined. [ Result] The percentage of carcass yield and percentage of abdominal fat were significantly higher in the group Ⅲ than in the group Ⅱ （P 〈 0.05）. The percentage of small intestine weight in slaughter weight was lower in the group Ⅱ than in other groups. [ Conclusion] Diets supplemented broad-rang and highly active NSP enzyme products can promote absorption of routine feed ingredients, increase meat yield, and improve meat performance.

Appropriate Metabolic Energy, Crude Protein, Calciumand Available Phosphorus Levels of Diet for BlackMuscovy Duck at 43-91 Days of Age

[Objective] The paper was to study the effects of diet formulation with different nutrition levels on growth and slaughter performance ofblack muscovy duck at the age of 43-91 days. [Method] Totally 288 individuals of 43dayold black muscovy duck were randomly divided intonine treatments, four repeats each treatment and eight ducks each repeat. UsingL9 （34） orthogonal experiment design （four factors and three levels）,three metabolic energy levels （12.32, 12.72, 13.12 MJ/kg）, three crude protein levels （14%, 16%, 18%）, three calcium levels （0.6%, 0.8%, 1.0%）and three available phosphorus levels （0.30%, 0.45%, 0.6%） were designed, and a total of nine feeding groups （C1C9） were designed according todifferent nutritional levels. Through combination of feeding test （49 d） and metabolic test （pretest 4 d and formal test 3 d）, the growth performance,meat performance and apparent nutrient digestibility of ducks were determined. [Result] The ducks in experimental group C2 had the highest average daily gain, the lowest feed gain ratio, the largest body oblique length, chest width, chest depth and tibia length, which had significant or extremely significant differences with other groups （P〈0.05 or P〈0.01）. The slaughter rate, semieviscerated rate, eviscerated rate and meat quality ofducks in C2 group were higher （P〈0.05）. The apparent digestibility of crude protein and dietary metabolic energy in C2 group were 88.68% and63.07%, respectively, both were significantly or extremely significantly higher than the other groups（P〈0.05 or P〈0.01）, while the interaction effectof calcium and phosphorus level on apparent digestibility was not obvious. [Conclusion] Under the experimental conditions, the suitable metabolicenergy, crude protein, calcium, available phosphorus and total phosphorus levels of 43 -91 days old black muscovy ducks were 12.32 MJ/kg,16.10%, 0.92%, 0.45% and 0.68%, respectively.