Dietary Yucca schidigera extract (YSE) could enhance immune function in broilers, which was attributed primarily to its saponin components. However, YSE also contains phenolic compounds which possess antioxidant ability. This study tested the effects of YSE on growth performance of broilers, its antioxidative enzyme activities and corresponding gene expressions in the small intestine. A total of 128 15‐day‐old broilers were randomly assigned to 4 treatments: corn‐soya bean meal as the basal control diet or the basal diet containing either 100, 200 or 300 mg/kg of YSE. Each treatment consisted of four replicate pens with eight broilers per pen. The experiment lasted 28 days which was divided into a grower period (day: 15–28) and a finisher period (day: 29–42). On day 28 and day 42 body weight (BW), feed intake (FI) and feed conversion rate (FCR) were recorded. Duodenum, jejunum and ileum were collected to analyse superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities, malondialdehyde (MDA) concentrations, total antioxidant capacity (T‐AOC) and gene expressions of SOD, CAT, GPx. The results showed that during the grower period a diet including 100 mg/kg YSE improved CAT capacity in the ileum, tended to increase activities of GPx in the duodenum, and further showed enhancing tendencies in SOD and GPx abilities in ileum. Gene expressions of CAT, SOD and GPx in the ileum tended to upregulate at 100 mg/kg YSE level. In the finisher period and over the whole period, all YSE groups had a reduced FI compared to the control group without compromising BW; 100 and 200 mg/kg YSE significantly improved FCR. In conclusion, the improved growth performance of broilers during the finisher period may be due to enhanced antioxidative ability in the grower period with YSE supplementation. This study provided evidence of using YSE as an additive to enhance growth in broilers. 相似文献
The objective of this study was to investigate the effect of storage temperatures and time on discoloration and oxidation of prepared chicken breast with paprika oleoresin. Freshly prepared chicken breast containing paprika oleoresin was stored at ?2, ?10, ?18°C, and an oscillating temperature between ?10 and ?18°C (?10/?18°C). A significant decrease in redness was detected at ?2, ?10, and ?10/?18°C. The lowest TBARS values and carbonyl contents were observed in the samples stored at ?18°C for 5 weeks. Also, the values of sulfhydryl groups gradually decreased with the increase in storage temperatures and duration. The results suggest a positive correlation between the loss of redness and oxidation in all samples. The findings indicated that the discoloration and oxidation of prepared chicken breast added with paprika oleoresin were inhibited significantly when stored at ?18°C. 相似文献
Seventy-nine velogenic Newcastle disease virus (NDV) isolates were obtained from infected chicken flocks during the outbreaks of Newcastle disease (ND) in various regions of the mainland of China in 2006. The F gene fragment (535 bp, from nt 47 to 581 of the F gene) which codes the main functional region of the F protein was obtained by RT-PCR and sequenced. All sequences obtained in this study have been submitted to GenBank. All the isolates have the motif 112R-R-Q/R-K/R-R-F117 at the cleavage site of the fusion protein, which is typical of velogenic NDV isolates. For genotyping, a phylogenetic tree based on nucleotides 47–435 of the F gene was constructed, and the 79 isolates could be divided into two genotypes, namely VIId and III. Most of the isolates proved to be of genotype VIId; only two isolates were of genotype III. Genotype VIId NDV has been the predominant pathogen responsible for most Newcastle disease outbreaks in China. The proportion of isolates of genotype VIId NDV shows an increasing trend, according to studies on the molecular epidemiology of NDV in China from 2002 to 2006. 相似文献
The pharmacokinetics of doxycycline in ducks were investigated after a single intravenous (IV), intramuscular (IM) or oral (PO) dose at 20 mg/kg body weight.
The concentrations of doxycycline in plasma samples were assayed using a high performance liquid chromatography method, and pharmacokinetic parameters were calculated using a non-compartmental model.
After IV administration, doxycycline had a mean (±SD) distribution volume (Vz) of 1761.9 ± 328.5 ml/kg and was slowly eliminated with a terminal half-life (t1/2λz) of 21.21±1.47 h and a total body clearance (Cl) of 57.51 ± 9.50 ml/h/kg. Following PO and IM administration, doxycycline was relatively slowly absorbed – the peak concentrations (Cmax) were 17.57 ± 4.66 μg/ml at 2 h and 25.01 ± 4.18 μg/ml at 1.5 h, respectively. The absolute bioavailabilities (F) of doxycycline after PO and IM administration were 39.13% and 70.71%, respectively.
The plasma profile of doxycycline exhibited favourable pharmacokinetics characteristics in Muscovy ducks, such as wide distribution, relatively slow absorption and slow elimination, though oral bioavailability was low.