Journal of Poultry Science最新文献

A 35-day experiment was conducted to evaluate the effects of the supplementation of mineral detoxified sulfur dispersion ((DSD); Patent No.: 10-1997773) on the growth performance, meat quality, excreta microbiota, gas emissions, nutrient digestibility, and blood profiles of broilers. In total, 720 one-day-old ROSS 308 broilers, with an initial body weight of 41.9±0.8 g, were divided into two (2) treatment groups with 20 replicate pens/groups composed of 18 birds per pen. Treatments consisted of 1) CON (the control), normal drinking water and 2) TRT (the treatment group), CON+0.001% DSD (1000:1 dilution ratio). Average daily feed intake (ADFI) and feed conversion ratio (FCR) increased in the TRT group (P<0.05) between days 1 to 7 and days 7 to 21 of the experimental period. Similarly, body weight gain (BWG) showed a significant increase (P<0.05) in the DSD-supplemented group throughout in the length of the experiment. With regard to meat quality, redness (a*) was higher, while drip loss was lower, on the 7^th day in the DSD group. Furthermore, DSD supplementation increased (P<0.05) Lactobacillus excreta but decreased E. coli concentrations in the TRT group compared to the CON group. Notably, nutrient digestibility, excreta gas emission, and blood profiles did not show any significant differences (P>0.05). DSD supplementation, administered through drinking water, has a positive impact on the growth performance, meat quality, and excreta microbiota of broiler chickens.

Japanese indigenous chickens include approximately 50 breeds exhibiting various morphological traits, such as a long tail. These genetic resources will be important for revealing the genetic basis of morphological traits in the future. However, little is known about the phenotypic characteristics of each breed during the growth stages. To understand age-dependent changes in growth and morphological traits, we investigated tail length, tail number, body weight, and shank length at several time points using three genetically distinct Japanese indigenous chicken breeds. A total of 155 birds from the Tosa-jidori, Chabo, and Minohikichabo breeds were used for trait measurements from 1 to 36 weeks of age to reveal breed and sex effects. Significant sex differences through the growth stages were observed for all traits except for tail number. Although there were no clear breed differences in tail length traits at the 6- and 20-week stages, Minohikichabo ultimately had a significantly longer tail due to extended tail feather growth at later stages (28 and 36 weeks). By measuring two tail length variables (central and maximum), it was revealed that the shape of the tail feathers varies with the growth stage. Minohikichabo's tail number was higher than that of Tosajidori and Chabo at earlier ages (8 and 16 weeks), which leads to an elegant visual in Minohikichabo. Tosa-jidori's body weight was higher than that of Chabo and Minohikichabo, whereas the shank lengths of Chabo and Minohikichabo were shorter than those of Tosa-jidori. These differences in body weight and shank length were consistent from the early to late growth stages. These results revealed the age-dependency of growth and morphological trait breed characteristics.

The reproductive performance of broiler breeder chickens noticeably decreases toward the end of their commercial lives. Herein, we determined the effects of vitamin E and selenium dietary supplementation on semen traits, egg fertility (defined as fertilization and hatching rates) of adult (49-week-old) and older (63-week-old) Red Cornish breeders. We found that both vitamin E and selenium were concentrated in the liver and adipose tissue of adult and older Red Cornish breeders, and were transferred to the semen and egg yolk, respectively, in proportion to the level of supplementation. Vitamin E supplementation, in particular, improved ejaculate volume, total sperm count, sperm motility, and viability in both adult and older roosters, whereas selenium improved sperm motility and viability in the adult roosters. Egg fertility increased following supplementation with either vitamin E or selenium. The hatching rate also improved by both supplements in proportion to the level of supplementation. No significant synergistic effects of vitamin E and selenium were found. The levels of egg fertility and sperm trait improvements diminished with the age of the birds and depended on vitamin E and/or selenium doses. Thus, as dietary vitamin E and selenium supplements improved semen quality and egg fertility in these older Red Cornish broiler breeders, such birds could be maintained in flocks to prolong their reproductive output.

The aim of this study was to evaluate the effects of dietary supplementation of calcium propionate and calcium butyrate on the laying performance, eggshell quality, and expression of genes related to calcium and phosphorus metabolism in the tibia. One hundred and twenty 70-week-old Isa Brown hens were randomly assigned to three treatments, and each treatment had four replicates of 10 birds fed a basal diet (control) or a basal diet supplemented with 0.5% calcium propionate (CP) or 0.5% calcium butyrate (CB) for 8 weeks. The CB and CP treatments had no significant effect (P>0.05) on the laying rate, egg production, egg weight, and feed efficiency. The eggshell percentage was increased from week 2 (P<0.05) and eggshell thickness was elevated at week 8 (P<0.01) by both CP and CB treatments. Compared to the control treatment, the CB treatment increased serum calcium and phosphorus levels at week 4 (P<0.05), whereas the CP and CB treatments decreased serum phosphorus at weeks 6 and 8, respectively (P<0.05). Dietary supplementation had no effect on the bone index and bending strength of the tibia (P>0.05). The calcium and phosphorus content of the tibia was decreased by the CB treatment (P<0.05). In the spleen, NF-κB and IL-6 transcript levels were not influenced (P>0.05) but TNF-α transcript levels were decreased by the CP treatment (P<0.05). In the tibia, the expression levels of NF-κB, TNF-α, and IL-17 were not affected by the CP or CB treatment (P>0.05). The CP and CB treatments had no significant effect on the transcript levels of RANKL, OPG, RNUX2, OPN, α-Clotho, and VDR (P>0.05). In contrast, PHEX transcript levels were increased by the CP treatment (P<0.05). The expression levels of osteocalcin (P=0.094) and FGF23 (P=0.087) tended to decrease under the CB treatment. In conclusion, dietary supplementation of 0.5% calcium butyrate or 0.5% calcium propionate improved the eggshell quality of aged laying hens, possibly as a result of decreased deposition or enhanced mobilization of bone calcium and phosphorus.

Sperm drastically change their flagellar movement in response to the surrounding physical and chemical environment. Testicular sperm are immotile; however, they gain the competence to initiate motility during passage through the male reproductive tract. Once ejaculated, the sperm are activated and promptly initiate motility. Unlike mammals, ejaculated sperm in birds are stored in specialized tubular invaginations referred to as sperm storage tubules (SSTs), located between the vagina and uterus, before fertilization. The resident sperm in the SSTs are in a quiescent state and then re-activated after release from the SSTs. It is thought that avian sperm can undergo motility change from quiescent to active state twice; however, the molecular mechanism underlying sperm motility regulation is poorly understood. In this short review, we summarize the current understanding of sperm motility regulation in male and female bird reproductive tracts. We also describe signal transduction, which regulates sperm motility, mainly derived from in vitro studies.

Protein synthesis in skeletal muscle is considered one of the most energy-consuming cellular processes. AMP-activated protein kinase (AMPK) is a metabolic master switch that regulates glucose and lipid metabolism, and it is implicated in protein synthesis control in skeletal muscles. The mechanistic target of rapamycin complex 1 (mTORC1) is a central regulator of protein metabolism in cells. However, the effect of AMPK activation on protein synthesis and mTORC1 signaling in chicken skeletal muscle remains unclear. Therefore, in this study, we aimed to investigate the effect of 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR), an AMPK activator, on protein synthesis and mTORC1 signaling in chick myotube cultures. The incubation of chick myotubes with AICAR (1 mM) for 3 h led to a significant increase in AMPK (Thr172) phosphorylation. Nonetheless, protein synthesis, measured using the surface sensing of translation method, was significantly decreased by AICAR. In addition, the phosphorylation of p70 ribosomal S6 kinase 1 (S6K1, Thr389), S6 ribosomal protein (Ser240/244), and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1, Thr37/46) was significantly reduced by AICAR. These results suggest that AMPK activation suppresses protein synthesis and mTORC1 signaling (through the phosphorylation of S6K1, S6 ribosomal protein, and 4E-BP1) in chick myotubes.