Genistein increases progesterone secretion by elevating related enzymes in chicken granulosa cells.

Genistein, a biologically active isoflavone, exists in many soy products. It is well known that genistein binds to both oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERß), but it has a higher affinity to ERß. Genistein can also bind to the G protein-coupled receptor 30 (GPR30, also known as G protein-coupled oestrogen receptor 1 or GPER). Furthermore, weak oestrogenic activity has been found in genistein, but the mechanism of action remains unknown. The aim of this study was to investigate the in vitro effects of genistein on the secretion of progesterone (P4) and oestradiol (E2) in chicken granulosa cells harvested from follicles, as well as the mRNA expression of ERs in these cells. In addition, we examined the expression of key enzymes including steroidogenic acute regulatory protein (StAR), cytochrome P450 side-chain cleavage (P450scc), and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) in the process of P4 synthesis. The results showed that genistein did not affect the viability of granulosa cells, nor was the proliferating cell nuclear antigen (PCNA) protein changed. Among the 1-, 10-, 100-, and 1,000-nM concentrations tested, treatment with 1 nM genistein for 48 h significantly increased P4 but did not affect E2 secretion. Real-time PCR results showed that the ERß gene expression in granulosa cells was markedly upregulated by 1 nM genistein treatment for 48 h, but there was no significant difference in ERα and GPR30 expression. Genistein also increased the gene expression of StAR, P450scc and 3ß-HSD in the cultured granulosa cells. These results indicate that genistein acts directly on chicken granulosa cells to increase P4 production by upregulating the gene expression of key enzymes through binding in ERß. It may exert positive effects on the reproduction of late-laying hens and act as an effective and safe feed additive for animals.

Effects of outdoor access days on growth performance, carcass yield, meat quality, and lymphoid organ index of a local chicken breed.

An experiment was conducted to evaluate the effect of outdoor access days on growth performance, carcass yield, meat quality, and lymphoid organ index of a local chicken breed. In total, 864 twenty one-day-old male Suqin yellow chickens, with similar body weight (536±36g), were selected and raised in indoor floor pens that measured 1.42×1.42 m (2 m2, 18 birds/m2) in conventional poultry research houses (36 birds per pen). Two hundred and sixteen birds were allowed outdoor access treatments at 21, 28, 35, and 42 d of age, respectively (access to outdoor for 35, 28, 21, and 14 days, respectively). Each treatment was represented by 6 replicates (pens) containing 36 birds (216 birds per treatment). In the outdoor access treatment, the birds had an outdoor free-range paddock that measured 3×8 m (24 m2, 1.5 birds/m2). The body weight of birds at 56 d of age increased linearly with increasing outdoor access days (P<0.001), but there was no effect of the outdoor access days on the body weight at 42 d of age (P=0.161). The daily weight gain, daily feed intake, and feed per gain from 21 to 42 d of age were unaffected by outdoor access days (P=0.401, P=0.463, P=0.223, respectively). However, the daily weight gain and daily feed intake from 42 to 56 and from 21 to 56 d of age increased linearly with increasing outdoor access days (P=0.002, P<0.001; P=0.001, P=0.004; respectively), while the feed per gain tended to decrease linearly from 21 to 56 d of age (P=0.060). The mortality from 21 to 56 d of age was unaffected by outdoor access days (P=0.261). At 56 d of age, the breast yield increased linearly with increasing outdoor access days (P<0.001), while the foot yield decreased linearly (P=0.016). The light (L*) and red (b*) values of leg meat color increased linearly with increasing outdoor access days (P=0.032, P=0.013, respectively). The spleen: the body weight ratio showed a decreasing and then increasing quadratic response to increasing outdoor access days (P=0.047). The litter moisture content at 42 and 56 d of age increased linearly with increasing outdoor access days (P<0.001, P=0.013, respectively). The findings of this study suggest that increasing outdoor access days advantageously affects the body weight, daily weight gain, feed per gain and breast yield as well as the light (L*) and red (b*) values of leg meat color, while decreasing foot yield.

Effect of free-range days on a local chicken breed: growth performance, carcass yield, meat quality, and lymphoid organ index.

An experiment was conducted to evaluate the effect of free-range days on growth performance, carcass yield, meat quality, and lymphoid organ index of a local chicken breed. In total, 1,000 one-day-old male Suqin yellow chickens were raised for 21 d. On d 21, 720 birds with similar BW (536 ± 36 g) were selected and randomly assigned to free-range treatment at 21, 28, 35, and 42 d of age (assigned to free-range treatment for 21, 14, 7, and 0 d, respectively). Each treatment was represented by 5 replicates (pens) containing 36 birds (180 birds per treatment). All the birds were raised in indoor floor pens measuring 1.42 × 1.42 m (2 m(2), 18 birds/m(2)) in conventional poultry research houses before free-range treatment. In the free-range treatment, the chickens were raised in indoor floor houses measuring 3 × 5 m (15 m(2), 2.4 birds/m(2)). In addition, they also had an outdoor free-range paddock measuring 3 × 8 m (24 m(2), 1.5 birds/m(2)). The BW of birds after being assigned to free-range treatment for 7 d decreased significantly compared with that in the conventional treatment (P < 0.05). However, there was no effect of the free-range days on the BW at 42 d of age (P > 0.05). The daily weight gain, feed per gain, daily feed intake, and mortality from 21 to 42 d of age were unaffected by free-range days (P > 0.05). At 42 d of age, the breast yield increased linearly with increasing free-range days (P < 0.05), whereas the thigh, leg, thigh bone, and foot yields decreased linearly (P < 0.05). The lung yield showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The water-holding capacity of the thigh muscle decreased linearly with increasing free-range days (P < 0.05), whereas there was no significant difference in the meat color, shear force, and muscle pH (P > 0.05). The absolute thymus weight and thymus:BW ratio showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The findings of this study suggest that increasing free-range days advantageously affects breast yield, but decreases thigh, leg, thigh bone, and foot yields as well as the water-holding capacity of thigh. No evidence was found that increasing free-range days caused changes in growth performance, meat quality, and lymphoid organs except for changes in water-holding capacity and thymus.

Molecular cloning and tissue distribution of peroxisome proliferator-activated receptor-alpha (PPARα) and gamma (PPARγ) in the pigeon (Columba livia domestica).

1. Peroxisome proliferator-activated receptors (PPAR) are involved in lipid metabolism through transcriptional regulation of target gene expression. The objective of the current study was to clone and characterise the PPARα and PPARγ genes in pigeon. 2. The full-length of 1941-bp PPARα and 1653-bp PPARγ were cloned from pigeons. The two genes were predicted to encode 468 and 475 amino acids, respectively. Both proteins contained two C4-type zinc fingers, a nuclear hormone receptor DNA-binding region signature and a HOLI domain (ligand binding domain of hormone receptors), and had high identities with other corresponding avian genes. 3. Using quantitative real-time PCR, pigeon PPARα gene expression was shown to be high in kidney, liver, gizzard and duodenum whereas PPARγ was predominantly expressed in adipose tissue.

Safety evaluation of phytosterols in laying hens: effects on laying performance, clinical blood parameters, and organ development.

Phytosterols are intended for use as a novel food ingredient with plasma cholesterol-lowering activity. Although phytosterols are naturally present in the normal diet, daily consumption is insufficient to ensure plasma cholesterol-lowering levels. Therefore, phytosterols may be added to the diets to achieve the desired cholesterol-lowering activity. A subchronic laying hen safety study was conducted to examine if high-dose phytosterols could affect the safety of hens. Three hundred sixty 21-wk-old Hy-Line Brown laying hens were randomly assigned to 5 groups with 6 replicates of 12 birds each; after 3 wk, birds were fed diets supplemented with 0, 20, 80, 400, and 800 mg/kg of phytosterols for 12 wk. Throughout the study, clinical observations and laying performance were measured. At the end of the study, birds were subjected to a full postmortem examination: blood samples were taken for clinical pathology, selected organs were weighed, and specified tissues were taken for subsequent histological examination. No treatment-related changes that were considered to be of toxicological significance were observed. Therefore, a nominal phytosterol concentration of 800 mg/kg was considered to be the no-observed-adverse-effect level.

Reduction of angiocidin contributes to decreased HepG2 cell proliferation.

BACKGROUND: Angiocidin plays a key role in angiogenesis and tumor progression. High angiocidin expression is detected in some kind of solid tumors and tumor vascular endothelial cells. Several reports have shown the inhibition of angiogenesis and tumor growth caused by angiocidin. However, the role of angiocidin in liver cancers growth is still unclear. OBJECTIVES: To examine angiocidin expression in SMMC-7221 and HepG2 cells and the role of angiocidin in liver cancer cell growth. METHODS: RT-PCR and western blot are used in this study to detect angiocidin expression. SiRNA and MTT experiments are used in exploring the role of angiocidin in tumor cell growth. RESULTS: Our study showed high angiocidin expression in two kinds of liver cancer cells. Angiocidin protein production in HepG2 cells were reduced significantly by siRNA. When HepG2 cells were transfected with siRNA-angiocidin, these cells showed very low proliferation activity compared with control cells. Our study suggests that reduction of angiocidin may contribute to decreased proliferation activity in liver cancer cells. CONCLUSION: Angiocidin is highly expressed in liver cancer cells, and it may play a key role in tumor growth of liver cancers.

Safety evaluation of daidzein in laying hens: part I. Effects on laying performance, clinical blood parameters, and organs development.

Daidzein, an estrogen-like product, becomes increasingly popular as a dietary supplement, particularly for postpeak-estrus animals seeking a safe natural alternative to play a role of estrogen. However, there is little available safety data of it for raisers and consumers. A subchronic laying hen safety study was conducted to examine if the high-dose daidzein could affect the safety of hens selves, including laying performance, clinical blood parameters and organs development. Seven hundred and sixty-eight 56-week-old Hyline Brown were randomly assigned to 4 groups with 8 replicates of 24 birds each and 3weeks later fed diets supplemented with 0, 10, 50 and 100mg of daidzein/kg for 12weeks. The mortality was significantly decreased (P<0.05). No treatment related adverse clinical signs were observed. Mean egg production, egg mass and feed conversion of whole experiment period was significantly influenced by dietary daidzein supplement (P<0.05), showing significant quadratic response to increasing dietary daidzein supplement (P=0.029, P=0.003 and P=0.019, respectively). There was no statistically significant changes in haematology (P>0.05). In clinical chemistry parameters, total protein, total cholesterol, calcium and phosphorus were significantly affected by dietary daidzein supplement (P<0.05). The no observed adverse effect level (NOAEL) is considered to be 50mg/kg.

Safety evaluation of daidzein in laying hens: part II. Effects on calcium-related metabolism.

Daidzein, an estrogen-like product, has become increasingly popular as a dietary supplement, particularly for postpeak-estrus animals seeking a safe natural alternative to play a role of estrogen. However, there is little available safety data of it for raisers and consumers. A subchronic laying hensafety study has been conducted to examine if the high-dose daidzein could affect calcium-related metabolism (eggshell quality and bone mineralization). Seven hundred and sixty-eight 56-week-old Hyline Brown were randomly assigned to 4 groups with 8 replicates of 24 birds each (192 laying hensper group) and 3weeks later fed diets supplemented with 0(control), 10, 50 and 100mg of daidzein/kg for 12week. Eggshell thickness, eggshell percentage, eggshell strength, eggshell Ca concentration was increased linearly with increasing dietary daidzein supplementation (P=0.001, P=0.007, P=0.002 and P=0.000, respectively). Serum Ca increased linearly with increasing dietarydaidzein supplementation (P=0.042), and serum P showed a significant quadratic response to dietarydaidzein supplementation (P=0.036). Bone ash and bone Ca were significantly influenced by dietarydaidzein supplementation (P<0.05). These findings indicate that daidzein hold no observed adverse effect on calcium metabolism, but also a safe and effective food additive for calcium metabolism in animals and humans.

Effects of stocking density on growth performance, carcass yield, and immune status of a local chicken breed.

An experiment was conducted to evaluate the effect of stocking density on growth performance, carcass yield, and immune status of a local chicken breed. In total, 840 one-day-old male Suqin yellow chickens were placed into 4-m(2) cages in groups of 50 (low), 70 (medium), or 90 (high) birds. Each treatment was represented by 4 replicates (cages). The cages measured 2.84 × 1.42 m; half of the area of the cage (2 m(2)) was used from 1 to 28 d and the whole cage was used from 29 to 42 d. Stocking densities were 25, 35, and 45 birds/m(2) from 1 to 28 d and 12.5, 17.5, and 22.5 birds/m(2) from 29 to 42 d (low, medium, and high, respectively). Final production (live bird mass after fasting) per unit area was 14.46, 19.46, and 24.23 kg/m(2), respectively, at 42 d of age. Several immune parameters were evaluated, and the growth performance, carcass yield, and meat quality were determined. Body weight at 28 and 42 d of age was significantly reduced as the stocking density increased (P < 0.05). A depression in daily weight gain was noticed from 1 to 28 d and 1 to 42 d of age, and daily feed intake decreased significantly in each period as density increased (P < 0.05). The feed/gain from 29 to 42 d and from 1 to 42 d of age decreased as density increased (P < 0.05). At 42 d, there was no effect of the stocking density on carcass, eviscerated carcass, breast, and abdominal fat yields (P > 0.05). The thigh yield of chickens in the medium-density group improved significantly (P < 0.05) compared with those of the other 2 groups. The water-loss rate, shear force, and meat color of the muscle were unaffected (P > 0.05) by the stocking density, but pH values increased slightly as density increased. No significant difference was noted in the immunological parameters, but the blood total protein and potassium were significantly affected by stocking density (P < 0.05). The findings of this study suggest that increasing the stocking density advantageously affected feed/gain and decreased the final BW, whereas no evidence was found that stocking density caused changes in any of the measured immune parameters.