Expression of chicken epidermal growth factor (cEGF) in Escherichia coli regulates the microflora structure of the duodenum to improve growth performance and intestinal morphogenesis in broilers.

1. A study used gene synthesis to obtain the functional domains of chicken epidermal growth factor (cEGF) and examined their impact on broiler growth performance, small intestinal morphology, digestive enzyme activities in the intestinal contents and the structure of duodenal microflora.2. The pET-32a-cEGF recombinant expression vector was constructed. The specific band at 26 KDa was shown by SDS-PAGE analysis and WB results. The purified protein content was shown to be 1687 µg/ml by assay.3. A total of 180 healthy, one-day-old Arbor Acres male, white-feathered broilers were randomly divided into three dietary treatment groups (six replicate pens, 10 birds per replicate): A control diet (ND); cEGF diet (cEGF), control supplemented with 250 mg/kg cEGF and the control diet (CD) supplemented with 250 mg/kg chlortetracycline.4. The results showed that feeding the cEGF and CD diet reduced FCR of broilers aged 1-21 d, average daily feed intake (ADFI) at 22-42 d, and the FCR in the whole period (1-42 d; p < 0.05). Compared with the ND group, the cEGF diet increased duodenal α-amylase and alkaline phosphatase activities in the 1-21 d, duodenal lipase, alkaline phosphatase, and ileal alkaline phosphatase activities in the post-period and increased villus height in the duodenum and ileum (p < 0.05). In addition, the ACE and Chao1 index for the birds fed cEGF were higher than the ND group (p < 0.05). At the phyla level, Firmicutes and Proteobacteria were dominant in all groups. At the genus level, the dominant genus was Lactobacillus. The LEfSe analysis showed that the cEGF group was enriched by 11 species including Brevibacillus, Eisenbergiella, Cloacibacterium, Butyricoccus spp.5. The addition of 250 mg/kg cEGF to the diet can increase growth performance by improving intestinal development and digestive enzyme activity, which may be related to the duodenal intestinal microflora. Therefore, cEGF is an effective alternative to antibiotics in broiler farming.

Effects of monoclonal antibody directed to LeY on implantation in the mouse.

The role of carbohydrates in embryo implantation in the mouse was investigated using an embryo transfer model and a blastocyst-uterine epithelial cell co-culture system. The monoclonal antibody (mAb) AH6 directed to LeY oligosaccharide (Fuc alpha1-2 Gal beta 1-4 [Fuc alpha1-3] GlcNAc) and other three mAbs directed to carbohydrates whose structures are closely related to LeY were used to show the effect of carbohydrate specificity on implantation. In the embryo transfer model, donor blastocysts (4 days post-coitus) were pretreated with mAb AH6 (experimental) or other mAbs (control) and transferred into one uterine horn of a recipient. The implantation rate was checked after 5 days. Implantation was significantly inhibited by mAb AH6 pretreatment, and inhibition was not observed in control groups. In the co-culture system, the attachment and outgrowth rate of blastocysts on the surface of uterine epithelial cells was significantly inhibited when monolayer epithelial cells or blastocysts were pretreated with mAb AH6. The most obvious effect of mAb AH6 was obtained during 2-4 h co-incubation. No inhibition was observed in the control groups. It was, therefore, concluded that oligosaccharide LeY recognized by mAb AH6 plays an essential role at the initial stage of implantation. It may act as a mediator molecule for adhesion between the surface of blastocyst and epithelial cell, and its function is carbohydrate-specific.

Hormone concentrations before and after semen-induced ovulation in the bactrian camel (Camelus bactrianus).

During the follicular phase of bactrian camels, basal concentrations of LH were 2.7 +/- 1.2 ng/ml. By 4 h after insemination peak values of 6.9 +/- 1.0 ng/ml occurred. In addition, a smaller LH peak (5.4 +/- 2.5 ng/ml) appeared 1 day before regression of the follicle began in unmated camels. During the follicular phase peripheral plasma progesterone values were low (0.36 +/- 0.28 ng/ml), but values increased to reach 1.73 +/- 0.74 ng/ml at 3 days and 2.4 +/- 0.86 ng/ml at 7 days after ovulation. Plasma oestradiol-17 beta concentrations were 26.8 +/- 9.0 pg/ml during the follicular phase and 30.8 +/- 5.1 pg/ml when the follicle was maximum size. Values fell after ovulation but rose to 29.8 +/- 6.5 pg/ml 3 days later.