In biological research, chicken embryos are a classic experimental model for the exploration of the embryonic development and cell differentiation.  Transferring exogenous substances into chicken embryos for producing medical antibodies has been widely used in the production practice.  However, there are few studies about the effect of the different injection site and dosage on chicken embryos.  The aim of this study was to explore the effects of different injection sites and dosages on chicken embryo hatching rate and development, so as to provide a basis for further studies using the chicken embryo model.  Freshly laid eggs (Rugao yellow chicken) were injected with different doses of saline at the tip, equatorial plane and the blunt end of the egg shell, respectively.  Egg hatching rate was recorded and compared among injection sites and different doses.  A trypan blue stain was also injected at the aforementioned sites and the growth of chicken embryos was observed.  The SPSS (statistical package for the social science) software was used to analyze the relationship between the chicken eggs hatching rate and the different injection sites or the different dosages.  The experimental results showed that there were significant differences on egg hatching rates among the different injection sites and doses (P<0.05).  The hatchability of the blunt end injection group was significantly higher than that of the other two sites.  The egg hatching rate decreased with increased saline doses.  The egg hatching rate of the 100 µL saline injection group was higher than the 200 and 300 µL dosage groups.  Ultimately, we suggest that the optimal chicken embryo injection process is during early development, at the blunt end site with a dose less than 100 µL to minimize damage to the egg.

To assess the effects of creatine pyruvate (Cr-Pyr) on lipid and protein metabolism in broiler chickens, a total of 400 1-day-old male birds (Aconred) were randomly allocated to four groups, with each group replicating four times and each replicate involving 25 birds. The broilers were provided with a commercial diet supplemented with Cr-Pyr at 0, 1, 5, or 10% of the diet, respectively, for a period of 3 wk ad libitum (from 22 to 42 d). In the present study, body weight (BW) and average daily gain (ADG) of broilers decreased in 10% Cr-Pyr group (P<0.01), whereas the relative leg and pectoral muscle weights were significantly higher than they were in the control group (P<0.05). 5 or 10% Cr-Pyr of diets decreased the abdominal fat rate (AFR, abdominal fat/live weight) of the broilers. The serum or hepatic triglyceride (TG) concentrations were significantly lower in the 5 and 10% groups (P<0.01). In contrast, Cr-Pyr caused a marked increase in the serum nonesterified fatty acid (NEFA), high-density lipoprotein cholesterol (HDL-C) and creatine kinase (CK) concentrations (P<0.01). Supplementation with Cr-Pyr (5 and 10%) in the diet also increased glucagons (GLU), insulin (INS) or leptin (LEP) contents (P<0.01). The expression of hepatic peroxisomal proliferators-activated receptor α (PPAR-α) and carnitine palmitoyl transferase-I (CPT-I), muscle insulin-like growth factor I (IGF-I) were significantly elevated and myostatin mRNA level was reduced in the 5 and 10% groups (P<0.05). It was found that supplementation with 5% Cr-Pyr improves both lipid and protein metabolism by regulating various metabolic parameters of broilers, while not adversely affects growth performance in broiler chickens.

Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before its commercialization. Population density, species dominance and population dynamics are important parameters of arthropods populations in field. So the impacts of three transgenic Bt rice strains expressing cry1Ab/cry1Ac, cry1C and cry2A on population density, species dominance and population dynamics of three species of planthoppers (Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus) and their three main predators (Cyrtorhinus lividipennis, Pirata subpiraticus and Theridium octomaculatum) were evaluated at three sites in Hubei Province, China, in the current study. The results showed that among three species of planthoppers, both in transgenic and non-transgenic rice field, the predominant species of planthoppers within phytophagous guild was S. furcifera at any site either growing season (46-50%). Significantly higher population density of N. lugens was observed in T2A-1 field relative to Minghui 63 field at Wuxue in 2010. The species dominance of predator, P. subpiraticus, in TT51 field was significantly higher than that in T1C-19 and T2A-1 fields in 2009 at Xiaogan site. Sampling date significantly influenced six arthropods except for P. subpiraticus in 2010. The interaction between rice strain×sampling date had no significant adverse effects on the population dynamics of three species of planthoppers and their predators, except for several individual species in 2009. The interaction among rice strain×sampling date×sampling site also had no significant effect on six arthropods except for S. furcifera in 2009. The results indicated that transgenic Bt rice expressing cry1Ab/cry1Ac, cry2A and cry1C had no significant adverse effects on the population dynamics of three planthoppers and their predators in most investigated data and sampling site.