Because of the presence of sperm storage tubules (SSTs) in the utero-vaginal junction (UVJ) in the oviduct, once ejaculated sperm enter the female reproductive tract, they can survive for a prolonged period in domestic birds; however, the specific mechanisms involved in sperm maintenance within the SST remain to be elucidated. In this study, we showed that transferrin (TF) and albumin (ALB) are expressed in SSTs. When UVJ extracts were subjected to size-exclusion column chromatography, we obtained fractions that extend sperm longevity in vitro. LC-MS/MS analysis of the two major proteins in the fractions identified these proteins as TF and ALB. Immunohistochemical analysis using specific antisera against TF and ALB indicated that both proteins were localized not only in the SSTs, but also in the surface epithelium of the UVJ. When the ejaculated sperm were incubated with either purified TF or ALB, sperm viability increased after 24 h. These results indicated that oviductal TF and ALB are involved in the process of sperm storage in SSTs and may open a new approach for technological improvement to prolong sperm longevity in vitro. 2020, Japan Poultry Science Association.L-Pipecolic acid is an intermediate of L-lysine catabolism. Its central injection exerted a hypnotic effect on the brain, which was partially mediated by the activation of γ-aminobutyric acid-A and γ-aminobutyric acid-B receptors. L-Proline has also been shown to exert a similar effect on N-methyl-D-aspartate receptors. Furthermore, L-pipecolic acid is known as L-homoproline, and both L-pipecolic acid and L-proline belong to the imino acid group; therefore, it is plausible that they share certain commonalities, including similar functions. However, the role of N-methyl-D-aspartate receptors with respect to the effects of L-pipecolic acid has not been examined yet. In the present study, the relationship between N-methyl-D-aspartate receptors and the central function of L-pipecolic acid was investigated in neonatal chicks. The behavioral postures for active wakefulness and standing/sitting motionless with eyes opened were significantly affected after intracerebroventricular injection of L-pipecolic acid; whereas, sitting motionless with head drooped (sleeping posture) was significantly enhanced. However, the N-methyl-D-aspartate receptor antagonist, MK-801, did not affect these changes. In conclusion, the central administration of L-pipecolic acid did not exert hypnotic effects through the activation of N-methyl-D-aspartate receptors in neonatal chicks. These results suggest that the imino group is not a determinant for activating N-methyl-D-aspartate receptors. 2020, Japan Poultry Science Association.Autophagy in the skeletal muscle increases under catabolic conditions resulting in muscle atrophy. This study investigated the effect of inhibition of mechanistic target of rapamycin (mTOR) on autophagy in chick skeletal muscle.  https://www.selleckchem.com/products/gdc6036.html  We examined the effects of Torin1, an mTOR inhibitor, on autophagy. Chick myotubes were incubated with Torin1 (100 nM) for 3 h. It was observed that Torin1 inhibited the phosphorylation of AKT (Ser473), p70 ribosomal S6 kinase 1 (S6K1, Thr389), S6 ribosomal protein (Ser235/236), and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1, Thr37/46), which are used for measurement of mTOR activity. Torin1 significantly (P less then 0.01) increased the LC3-II/LC3-I ratio, an index for autophagosome formation, while it did not influence the expression of autophagy-related genes (LC3B, GABARAPL1, and ATG12). In addition, Torin1 increased atrogin-1/MAFbx (a muscle-specific ubiquitin ligase) mRNA expression. Fasting for 24 h inhibited the phosphorylation of AKT (Ser473), S6K1 (Ther389), S6 ribosomal protein (Ser235/236), and 4E-BP1 (Thr37/46) in chick skeletal muscle and significantly (P less then 0.01) increased the LC3-II/LC3-I ratio. Fasting also increased GABARAPL1 and atrogin-1/MAFbx mRNA expression but not LC3B or ATG12 mRNA expression. These results indicate that mTOR signaling regulates autophagy and the ubiquitin-proteasome proteolytic pathway in chick skeletal muscle. 2020, Japan Poultry Science Association.Probiotic bacteria are known for their beneficial effects on the intestinal immune function of the host animal. However, their effects on mucosal barrier function in chicks are not completely understood. The aim of this study was to determine the effects of the probiotic bacterium, Lactobacillus reuteri (LR), on the gastrointestinal mucosal barrier function of broiler chicks. One day-old male broiler chicks were orally injected water (300 µL) with or without 1 × 108 cfu of LR (5 mg FINELACT, Asahi Calpis Wellness Co. Ltd.) every morning for 7 days (day 0 to 6). The crop, duodenum, ileum, and cecum were collected on day 7 and were used for histological analysis and RNA extraction. Then, the thickness of the mucosal structures and the number of goblet cells in the digestive tract were assessed using histological analysis. The expression of Mucin 2, factors related to the formation of tight junctions (Claudin1, 5, and 16, ZO2, and JAM2), cytokines (IL-6, CXCLi2, and IL-10), and avian β-defensin 10 (AvBDs) (AvBD2, 10, and 12) in the crop, duodenum, ileum, and cecum were analyzed using real-time polymerase chain reaction (PCR). Results showed that oral administration of LR increased ileal villus height and crypt depth, decreased Claudin16 level in the crop and increased JAM2 level in the crop and ileum, and decreased the expression of AvBD10 in the ileum and cecum and that of AvBD12 in the crop. It did not affect goblet cell number and Mucin 2 expression. These results suggested that LR used in this study may enhance mucosal barrier function by regulating tight junctions in the upper gastrointestinal tract. 2020, Japan Poultry Science Association.Eighty 14-d-old single-comb White Leghorn male chicks were divided into 16 groups with five birds each. Fructosyl-valine, which is a valine-glucose-Amadori product, was intravenously (2,250 nmol/kg body weight) or orally (300 µmol/kg body weight) administered to chicks. Blood samples were collected 15, 30, 60, 120, 180, 360, 720 and 1440 min after administration. Plasma concentrations of fructosyl-valine were measured by using a liquid chromatography / mass spectrometry (LC/MS). The time course change in plasma fructosyl-valine concentration showed an exponential curve, as y=a+be-λt. The half-life of plasma fructosyl-valine was calculated by the following equation (loge2)/λ. When fructosyl-valine was injected intravenously, the highest value for plasma fructosyl-valine concentration was observed 15 min after administration. When injected intravenously, the half-life of plasma fructosyl-valine was calculated to be 231 min. When fructosyl-valine was administered orally to chicks, the highest value for plasma fructosyl-valine concentration was observed 180 min after administration.