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A total of 480 one‐day‐old Arbor Acres broiler chicks were randomly assigned to four dietary groups, each including six replicates (n = 20/replicate). Broilers in the first group (G1) were fed a basal diet without any additives (control). Broilers in groups 2, 3 and 4 (G2, G3 and G4) were fed a basal diet supplemented with 0.1%, 0.2% and 0.4% coriander (Coriandrum sativum L.) seed powder (CSP) respectively. Feeding trials lasted for 42 days, and after that growth, carcass traits, haematological parameters, gut microbiota and economic efficiency (EE) were evaluated. Final body weight (FBW), total weight gain (TWG), total feed intake (TFI) and red blood cell (RBC) counts of broilers in the G4 and G3 treatment groups were significantly higher (p < .05) compared with broilers in the G1 treatment group. The feed conversion ratio (FCR) was better (p < .05) in the G4 treatment group (1.72) than in the G1 treatment group (1.84). Broilers in CSP treatment groups had significantly higher haemoglobin (Hb) concentrations, packed cell volume (PCV) and platelet counts, and had lower (p < .05) Escherichia coli and Clostridium perfringens counts compared with broilers in the G1 treatment group. Dressing, liver, pancreas, bursa and thymus percentages were higher (p < .05) in broilers in the G4 (70.30, 3.18, 0.31, 0.10 and 0.32% respectively) treatment group, compared with broilers in the control (G1) group (66.57, 2.37, 0.23, 0.04 and 0.21% respectively). Broilers in treatment groups G4 and G3 had lower percentages of abdominal fat and lower total bacterial counts (p < .05) than broilers in treatment groups G2 and G1. The highest economic efficiency (EE) was found in treatment group G4, and EE in this group was 13.06% greater than in the control (G1) group.  相似文献   
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This study was conducted using 120 multiparous Awassi ewes during the breeding season to compare the effects of using previously used controlled internal drug release (CIDR) on the hormone profiles, reproductive performance and economic measures of ewes. Ewes were randomized to receive one of five previously used CIDR (previously used for 6, 12, 18, 24 or 30 days) or the new CIDR as a control for 6 days (CIDR6, CIDR12, CIDR18, CIDR24, CIDR30, and CIDR0 [control], respectively). Blood samples were collected on four occasions, at the time of CIDR insertion, after 3 days of insertion, and at the time of withdrawal and insemination. Serum estradiol (E2) and progesterone (P4) concentrations were measured. Timed insemination was performed 48 hr post‐CIDR withdrawal. Pregnancy was diagnosed by ultrasonography 23 days after insemination and confirmed on day 35. The heat detection rate was significantly (p < 0.05) higher in the CIDR0 and CIDR6 groups than in the CIDR18 and CIDR30 groups. The total pregnancy rate and fecundity were significantly (p < 0.05) higher in the CIDR6 group than in other groups. P4 level was significantly (p < 0.05) higher in the CIDR0 group than in the CIDR30 group at the time of removal. At each time point, the E2 level was significantly (p < 0.05) higher in the CIDR6 group than at the other groups. The total variable cost, total cost, return and net profit were higher in the CIDR6 and CIDR0 groups than in the other groups. In conclusion, although previously used CIDRs are efficient at synchronizing oestrus in ewes, the duration of previously usage significantly affected the reproductive parameters and economic profit. CIDRs previously used for 6 days and new CIDRs provided the highest fertility and fecundity rates, besides return and net profit. Economically, it is not advisable to use CIDRs that previously used for 12 days or more.  相似文献   
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Tropical Animal Health and Production - This study aimed at investigating the relationship between concentrations of macro and trace elements in blood serum, and fluids from small and large...  相似文献   
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Transgenic research on cattle embryos has been developed to date using viral or plasmid DNA delivery systems. In this study, a different gene delivery system, piggybac transposition, was employed to investigate if it can be applied for producing transgenic cattle embryos. Green or red fluorescent proteins (GFP or RFP) were transfected into donor fibroblasts, and then transfected donor cells were reprogrammed in enucleated oocytes through SCNT and developed into pre-implantation stage embryos. GFP was expressed in donor cells and in cloned embryos without any mosaicism. Induction of RFP expression was regulated by doxycycline treatment in donor fibroblasts and pre-implantational stage embryos. In conclusion, this study demonstrated that piggybac transposition could be a mean to deliver genes into bovine somatic cells or embryos for transgenic research.  相似文献   
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The objective of this study was to evaluate the effects of quantitative feed restriction, along with dietary supplementation with a probiotic blend (Protexin) as a natural growth promoter, on the performance, water consumption, mortality rate and carcass traits of meat‐type quails. A total of 250 1‐day unsexed quails were randomly allocated to five equal groups in a completely randomized design. The first group (A) fed a basal diet without any restriction (24 hr/day); the second group (B1) fed the basal diet for 20 hr/day; the third group (B2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 20 hr/day; the fourth group (C1) fed the basal diet for 16 hr/day; and the fifth group (C2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 16 hr/day. Birds were fed ad‐libitum from 0–14 days of age, and then the feed restriction regimes started from 14 till 28 days of age. Results showed that quails in the control‐group consumed more feed and water than the other treatment groups (p < .01), however their body weights did not differ (p > .05) compared with the other treated groups. The best feed conversion values were achieved in quails supplemented with probiotic blend (B2 and C2) in comparison with the other groups (p < .01). Feeding probiotic had a positive effect on bird health which reduced the mortality rate. Further, mortality rate was significantly reduced (p < .05) by feed restriction, with or without probiotic supplementation. No carcass parameters were significantly affected (p > .05) by treatments. Our results show that quail could be reared under a feed restriction system, for 4–8 hr daily, along with dietary supplementation of probiotic as growth promoter for better growth performance.  相似文献   
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Modifying electrical activation conditions have been used to improve in vitro embryo production and development in pigs. However, there is insufficient information about correlations of porcine embryo development with oocyte pre‐ and post‐activation conditions. The purpose of this study was to compare the developmental rates of porcine oocytes subjected to different mannitol exposure times, either pre‐ or post‐electrical activation, and to elucidate the reason for the optimal mannitol exposure time. Mannitol exposure times around activation were adjusted as 0, 1, 2 or 3 min. Blastocyst development were checked on day 7. Exposure of oocytes to mannitol for 1 or 2 min before electrical activation produced significantly higher blastocyst rates than exposure for 0 or 3 min. There was no significant difference in blastocyst rates when activated oocytes were exposed to mannitol for 0, 1, 2 or 3 min after electrical activation. While exposure of oocytes to mannitol for 1 min pre‐ and 3 min post‐activation showed significantly higher blastocyst development than 0 min pre‐ and 0 min post‐activation. It also showed higher maintenance of normal oocyte morphology than exposure for 0 min pre‐ and 0 min post‐activation. In conclusion, exposure of oocytes to mannitol for 1 min pre‐ and 3 min post‐activation seems to be optimal for producing higher in vitro blastocyst development of porcine parthenogenetic embryos. The higher blastocyst development is correlated with higher maintenance of normal morphology in oocytes exposed to mannitol for 1 min pre‐ and 3 min post‐activation.  相似文献   
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