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991.
Distribution of immunoglobulin (Ig)-containing cells and secretory component in internal organs of two 15-day-old embryos and 17 chickens, 1 to 480 days old, were examined by fluorescent antibody technique. In 15-day-old embryos, Ig-containing cells were not found in gut, bursa, spleen, or thymus. The bursa of Fabricius synthesized IgM, IgG, and IgA in as young as 1-day-old chicks. In extrabursal organs, IgM-containing cells were already present in intestine of 1-day-old chicks, but IgA-containing cells appeared in intestine, thymus, and spleen between the 3rd and 7th day after hatching. Very few IgG-containing cells were in intestine on the 3rd and 7th day after hatching. Secretory component was found in epithelial surfaces of intestine and ductus choledochus of most chickens examined. The presence of secretory component and IgA-containing cells in intestine supported the existence of secretory-immunologic system in chickens. 相似文献
992.
993.
Ko JH Asano A Kon Y Watanabe T Agui T 《The Japanese journal of veterinary research》2004,51(3-4):123-133
The double-stranded RNA-dependent protein kinase (PKR) is induced in mouse and human cells on treatment with interferon. In this study, we have cloned and determined the nucleotide sequences of chicken PKR cDNA in various chicken breeds. Chicken PKR was a 550-amino-acid protein as deduced from the cDNA open reading frame (ORF), and there were specific domains (two double-stranded RNA binding domains (DRBDs) and numerous kinase subdomains) characterized in RNA binding proteins and kinase families. Furthermore, it was suggested that chicken PKR was polymorphic. Transfected cell clones expressing chicken PKR mRNA were demonstrated to confer antiviral responses to vesicular stomatitis virus, except for Koshamo type-3 (KS-3). KS-3 PKR, which has an amino acid substitution at position 507 (Arg to Gln), showed amphibious antiviral responses. This specific amino acid substitution was considered to determine the antiviral function of chicken PKR in addition to essential domains as DRBDs and kinase subdomains. 相似文献
994.
Medan M Watanabe G Absy G Sasaki K Sharawy S Taya K 《The Journal of reproduction and development》2004,50(4):391-397
Eighteen cyclic Shiba goats were used in this study. Estrus was synchronized with a single injection of 125 microg of a synthetic analogue of prostaglandin F(2)alpha (PGF(2)alpha) after detection of at least one corpus luteum by B-mode ultrasonography. Blood samples were collected from each animal on days 0, 7 and 21 post-mating for progesterone assay. Animals in estrus were either allowed to be mated by fertile bucks twice during estrus (group I; n=12) or not at all (group II; n=6). Ultrasonographic examinations were performed transrectally or transabdominally using a real-time B-mode scanner equipped with a 7.5 or 5 MHz transducer. All animals exhibited estrus 56.0 +/- 2.7 h after injection of PGF2alpha. The results show that the accuracy of the progesterone assay in diagnosing pregnancy on day 21 after mating was 80% for pregnancy and 100% for non-pregnancy, retrospectively. Ultrasonographic examinations showed that gestational sac and embryos heartbeats were detected on days 20.2 +/- 0.6 and 24.3 +/- 0.7 of gestation, respectively. Placentomes were detected on day 35.4 +/- 1.0 of gestation as small nodules (0.7 +/- 0.2 cm in size). At two months pregnancy, skeletal structures like skull, thorax and long bones were clear. Biparietal diameter of the skull and length of long bones could be used as an estimate of gestational age. The accuracy of detection of fetal number using real-time B-mode ultrasonography was 91.7% on day 60 of gestation. In conclusion, progesterone assay at day 21 post-mating (cut-off value, 1 ng/ml) can be used for pregnancy diagnosis in goats. However, B-mode transrectal ultrasonography was more efficient due to detection of embryo and confirmation of its viability by heartbeats. In addition, fetal number and gestational age could be determined only by ultrasonography. 相似文献
995.
Passive immunoneutralization of endogenous inhibin increases ovulation rate in miniature Shiba goats 总被引:2,自引:0,他引:2
Medan MS Watanabe G Nagura Y Kanazawa H Fujita M Taya K 《The Journal of reproduction and development》2004,50(6):705-710
We reported previously that passive immunization against inhibin enhances follicular growth and increases the ovulation rate. However, the ovulation rate was not comparable to the number of follicles. Therefore, the aim of this study was to attempt to increase the ovulation rate by increasing the interval between inhibin immunization and PGF2alpha injection. Five miniature Shiba goats were treated with 10 ml inhibin antiserum (inhibin-AS) developed against [Tyro30]-inhibin alpha (1-30). A control group (n=5) was treated with normal goat serum. All animals were injected intramuscularly with 125 microg PGF2alpha 72 h after treatment to induce estrus and ovulation. Blood samples were collected for hormonal assay and the ovulation rate was determined by laparotomy. In contrast to the control group, there was a significant increase in plasma concentrations of FSH in the immunized group. After luteolysis, plasma concentrations of estradiol-17beta increased markedly to a preovulatory peak about 2 folds higher (P<0.01) than that of controls. In addition, the ovulation rate was greater in the immunized group (14.4 +/- 2.2) than in the control group (2.2 +/- 0.6), and the mean number of follicles > or = 4 mm in diameter was 10.0 +/- 0.8 in the inhibin-AS group compared with 2.4 +/- 0.3 in control group. The present results demonstrate that immunoneutralization of endogenous inhibin increased FSH secretions in miniature shiba goats. The increased FSH secretion enhanced follicular growth and increased the ovulation rate. Additionally, increasing the interval between inhibin-AS and PGF2alpha injections (to 72 h) resulted in a greater ovulation rate compared with the previous protocol (48 h). Therefore, inhibin-AS treatment proved to be an effective alternative to exogenous gonadotropin methods for induction of superovulation in goats. 相似文献
996.
Shi Z Jin W Watanabe G Suzuki AK Takahashi S Taya K 《The Journal of reproduction and development》2004,50(6):605-611
In the present study, changes in localization of nerve growth factor (NGF) and its receptors, trkA and p75 in the ovary were investigated during the estrous cycle of the golden hamster. The effect of LH surge on changes in localization of NGF, trkA and p75 in the ovary was also investigated. NGF and its receptors trkA and p75 were localized in oocytes, granulosa cells and theca cells of various stages of follicles throughout the estrous cycle. NGF and its two receptors were also present in numerous interstitial cells and luteal cells. The number of interstitial cells staining positively for NGF and its two receptors was greater in ovaries of day 1 (day 1=day of ovulation) than the other days during the estrous cycle. Treatment with the antiserum against luteinizing hormone releasing hormone (LHRH-AS) at 1100 h on day 4 completely blocked ovulation. There were few positive reactions for NGF and its two receptors in interstitial cells 24 hr after LHRH-AS injection. The effect of LHRH-AS treatment was blocked by a single injection of 10 IU human chorionic gonadotropin. The distinct widespread distribution of NGF and its two receptors in the ovary of golden hamsters suggest that NGF may be an important growth factor for regulation of ovarian function. Furthermore, the LH surge may be an important factor for inducing production of NGF and its two receptors in interstitial cells of the cyclic golden hamster. 相似文献
997.
Watanabe T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(5):557-562
The development of sucking pressure was investigated with an artificial nipple in 16 male and female rat pups on postnatal days 4, 7, 10, 14, and 18. The rat pups refused to suck on the artificial nipple on postnatal day 14 or day 18 thus negative sucking pressure had to be calculated by regression analysis. As a result, the mean maximum intra-oral negative sucking pressure on day 18 was calculated to be -160.1 mmHg in the male and -103.4 mmHg in the female. Based on these results, the maximum level of negative pressure of the automated experimental rat milker was set at -160 mmHg. The automated experimental milker for rat is able to collect milk from lactating mothers by alternating negative and atmospheric pressures through two solenoid valves and a vacuum pump attached to a microcomputer. Mother rats were milked with the automated experimental milker on postpartum days 4, 7, 10, 14 and 18 of a single lactation period. The maximum mean milk yield with this machine was 3.18 +/- 1.37 g, obtained on day 14 of the lactation period. This quantity is considerably lower than previously reported values obtained by measuring differences in body weight of the offspring and mother rat before and after suckling. It is necessary to further optimize this system, but the milk yield in the present study is adequate for chemical analysis. 相似文献
998.
Kikuchi M Takao Y Tokuda N Ohnami Y Orino K Watanabe K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(11):1273-1274
Total 78 semen samples were obtained from 27 Thoroughbred stallions (aged 6 to 27 years), and were subjected to quantification of lactoferrin (Lf) in seminal plasma and examination of the seminal properties. The seminal plasma Lf concentration varied from 21 to 689 microg/ml, with a mean value of 244 +/- 151 microg/ml (S.D.). The seminal plasma Lf concentration and total seminal plasma Lf positively correlated with the sperm concentration (r=0.5938, P<0.001) and with the total sperm number (r=0.6959, P<0.001), respectively. There was no correlation between seminal plasma Lf and sperm motility. These results suggest that seminal plasma Lf reflects gonadal function. 相似文献
999.
Kawazu S Kishi H Saita E Jin W Suzuki AK Watanabe G Taya K 《The Journal of reproduction and development》2003,49(1):87-97
Gonadal function in the male golden hamster (Mesocricetus auratus) was investigated during exposure to a short photoperiod condition. Within 3 weeks of exposure to the short photoperiod condition, FSH and testosterone in the plasma significantly decreased, and subsequently immunoreactive (ir)-inhibin significantly decreased. Testicular contents of ir-inhibin and testosterone, and pituitary contents of LH and FSH also significantly decreased by 3 weeks with regression of weight of testes, epididymis and seminal vesicles and sperm head count. Circulating LH varied but not significantly. Thereafter, all reproductive parameters and secretion of LH, FSH, ir-inhibin and testosterone gradually recovered after 17 weeks of exposure even though animals continued to be subjected to the short photoperiod condition. Plasma concentrations of inhibin B and inhibin pro-alphaC were detectable and were significantly decreased after 15 weeks of exposure to the short photoperiod, but their levels were still detectable. Immunopositive reaction of inhibin alpha and betaB subunits was found in Sertoli cells and Leydig cells in the regressed testes of animals subjected to short photoperiod as was also seen in animals before exposure to the short photoperiod. Although the spermatogenic cycle was suppressed like prepubertal animals, the present study showed that the testicular recovery, so-called refractoriness, is functionally different from the developing stage of immature animals, especially with regard to inhibin secretion. The present results showed that changes in FSH preceded changes in inhibin during the regression and recovery phases, indicating that FSH is a major regulatory factor of inhibin secretion in male golden hamsters. The present study also demonstrated that regressed testes still secrete a small amount of bioactive inhibin during exposure to a short-photoperiod condition. 相似文献
1000.
Yamauchi N Takezawa T Kizaki K Herath CB Hashizume K 《The Journal of reproduction and development》2003,49(6):553-560
The objective of the present investigation was to study proliferative activity of fibroblast-like endometrial stromal cells in bovine endometrial caruncular (CAR) and intercaruncular (ICAR) areas that have distinct functions during implantation. Endometrial stromal cells were derived from CAR and ICAR of nonpregnant cows, and their proliferative potential was analyzed in an in vitro cell culture system. In addition, expression of four types of cell cycle regulatory molecules was analyzed by RT-PCR in samples of CAR, ICAR, cotyledon (COT) and fetal membrane of both artificially inseminated (AI) and somatic nuclear transferred (NT) cows on days 30 and 60 of gestation. The proliferation growth curve showed that the cells derived from CAR had higher proliferative activity than that of ICAR-derived cells. No morphological differences were found between the cells derived from CAR and ICAR at population-doubling levels (PDL) of the two. Most of the cells derived from ICAR of nonpregnant cows exhibited expanded shape with no further proliferation at PDL 6 with a lack of cyclin E expression. Of the regulatory molecules, cyclin D1, CDK2 and CDK4 were expressed in both CAR and ICAR cells derived from both nonpregnant, and AI cows on days 30 and 60 of gestation. The expression of cyclin E in both AI and NT cows was confined to COT and fetal membrane on day 30 of gestation. Cyclin E expression on day 60 of gestation in AI cows was observed in all but ICAR areas. In marked contrast, however, cyclin E expression on day 60 of gestation in NT cows was confined to COT, suggesting that poor placentation in these cows is possibly associated with a lack of cyclin E expression. These results suggest that CAR-derived stromal cells have higher proliferative potential, which may be related to cyclin E expression during implantation. 相似文献