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Schmidt Zhang posted an update 8 hours, 41 minutes ago
han vitamin D3 or double dosage vitamin D3 treatment. This indicated that the bone resorption rate was lower in cortical bone than that in trabecular bone in the late laying period. In conclusion, supplementation with dietary 25OHD could stimulate bone growth and increase bone volume in pullets to provide more space for mineral deposition during the laying period with positive effects on laying hen bone quality.We investigated effects of rearing cage type and dietary limestone particle size (LPS) on egg production, egg weight, eggshell, and bone quality in laying hens. The pullets were reared in conventional (CON; 20 chicks/cage, 270 cm2/chick) or furnished (FUR; 30 chicks/cage; 636 cm2/chick) cages and fed 3 LPS (fine, 0.05) femur and tibia BMD and BMC; at 24 woa, hens reared on medium LPS tended to have higher femur BMD (0.17 vs. 0.14 g/cm2; P = 0.079) and BMC (0.99 vs.0.78 g; P = 0.088) than hens reared on fine LPS. In conclusion, hens reared in furnished cages had better eggshell quality but had marginal effects on femur and tibia quality, whereas rearing dietary LPS had no effects on eggshell and bone attributes in hens.This study was aimed at estimating the dietary manganese (Mn) requirement for laying duck breeders. A total of 504 Longyan duck breeders (body weight 1.20 ± 0.02 kg) aged 17 wk were randomly allocated to 6 treatments. The birds were fed with a basal diet (Mn, 17.5 mg/kg) or diets supplemented with 20, 40, 80, 120, or 160 mg/kg of Mn (as MnSO4·H2O) for 18 wk. Each treatment had 6 replicates of 14 ducks each. Wnt inhibitor As a result of this study, dietary Mn supplementation did not affect the productive performance of laying duck breeders in the early laying period (17-18 wk), but affected egg production, egg mass, and feed conversion ratio (FCR) from 19 to 34 wk (P less then 0.05), and there was a linear and quadratic effect of supplement level (P less then 0.05). The proportion of preovulatory ovarian follicles increased (P less then 0.01) linearly and quadratically, and atretic follicles (weight and percentage) decreased (P less then 0.05) quadratically with dietary Mn supplementation. The density and breaking s containing 17.5 mg/kg of Mn, for Longyan duck breeders from 19 to 34 wk of age were estimated to be 84.2 for optimizing egg production, 85.8 for egg mass, and 95.0 for FCR. Overall, dietary Mn supplementation, up to 160 mg/kg of feed, affected productive performance, tibial characteristics, and serum biochemical and antioxidant status of layer duck breeders. Supplementing this basal diet (17.5 mg/kg of Mn) with 85 to 95 mg/kg of additional Mn was adequate for laying duck breeders during the laying period.Because of concerns over the use of antibiotics in poultry feed, this study was designed to determine the effectiveness of phytobiotic supplementation as an alternative to antibiotic use based on growth performance and meat characteristics of broilers exposed to Salmonella typhimurium. The effects of an antibiotic and 3 phytobiotic feed additives (PFA), Mix-Oil Mint (MOmint), Mix-Oil Liquid (MOliq), and Sangrovit Extra (Sangext), were compared. At day of age, 280 Ross chicks were randomly allocated into 6 treatments. At 15 d, all chicks except negative control were exposed to S. typhimurium. The offered 6 diets were as follows T1, negative control; T2, infected with S. typhimurium; T3, infected + avilamycin (0.1 g/kg); T4, infected + MOmint (0.2 g/kg); T5, infected + plant extract in liquid form MOliq (0.25 mL/L); and T6, infected + Sangext (0.15 g/kg). During the cumulative starter period, PFA improved performance over that of the control, and the food conversion ratio (FCR) was lower for T3 and T5 compared with T1 (P 0.05) in T2 and T5 compared with that in T1 and T4. Alanine transaminase concentration decreased significantly (P less then 0.01) in T4 and T5 compared with that in T1, T2, and T3. Treatments had significant effects on breast temperature and pH (P less then 0.001). A significant decrease in the myofibril fragmentation index occurred in T1 and T6. Hardness and chewiness were influenced by treatments (P less then 0.05). In conclusion, dietary supplementation with PFA could effectively compare with that of antibiotic avilamycin in the maintenance of growth performance and improvement in meat characteristics of broilers challenged with S. typhimurium.We investigated efficacy of in ovo application of epidermal growth factor (EGF) on intestinal expression of EGF receptor (EGFR) during embryogenesis (experiment 1) and posthatch growth performance and gastrointestinal development in broiler chickens (experiment 2). In experiment 1, 450 fertile Ross 708 eggs were allocated to 3 groups (150 eggs/group) 1) control, 2) 160 μg EGF/kg of egg, and 3) 640 μg of EGF/kg of egg. Eggs were candled for live embryos on day 16 and injected with the respective treatment solutions on day 17 and sampled for jejunal tissue from day 17 to hatch for EGFR analyses. There was no effect of EGF (P > 0.05) on EGFR expression on day 17 to 20; however, on day 21, EGF increased (P 0.05) on any posthatch response criteria. In conclusion, in ovo application of EGF increased EGFR expression but had no effect on posthatch growth performance, DM retention, and intestinal development. The lack of EGF effect on posthatch response was surprising but suggested in ovo application of EGF may not be a viable approach.This study was conducted to investigate the effects of dietary supplementation of Achyranthes japonica Nakai (AJN) extract as a natural feed additive on growth performance, nutrient utilization, cecal microbiota, excreta noxious gas emission, and meat quality in broilers fed corn-wheat-soybean meal diet. In total, seven hundred twenty 1-day-old male Ross 308 broilers with an average body weight (BW) of 43.36 ± 1.42 g were used in a 35-d feeding trial. Broilers were randomly assigned to 1 of the 4 treatments. Each treatment had 10 replication pens with 18 birds per replication. Dietary treatments composed of corn-wheat-soybean meal-based diets along with the addition of 0, 0.025, 0.05, and 0.1% of AJN extract. The BW gain and feed conversion rate were linearly influenced (P less then 0.05) by the supplementation of AJN extract during days 8 to 21, 22 to 35, and the overall experiment. At the end of the experiment, the digestibility of dry matter and nitrogen and the population of cecal lactic acid bacteria were linearly improved (P less then 0.