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51.
Improvement of rice (Oryza sativa L.) growth in upland conditions with deep tillage and mulch 总被引:1,自引:0,他引:1
The productivity of upland rice in Japan as well as in the world is low and unstable owing to scarce and unpredictable rainfall. The objective of this study was to examine whether agronomic methods could enhance grain yield of upland rice. Four field experiments were conducted from 2001 to 2003 in Nishitokyo, Japan, under upland conditions with different water supplies, in order to quantify the effects of deep tillage combined with deep placement of manure (50-cm depth), straw mulch (6 t ha−1), or their combinations on the growth and grain yield of rice. Mulch kept surface soil moisture higher than without mulch even at reproductive stage, and it increased yield to the greatest extent under the most favourable conditions with much rainfall before heading (i.e., 2003). Deep tillage with deep placement of manure induced deep root proliferation and higher nitrogen uptake, increasing biomass production, and panicle number, and consequently grain yield was enhanced under the two lowest yielding environments with less rainfall before heading. Rice plants with deep tillage with deep manure application without mulch tended to have lower leaf water potential and higher diffusion resistance during drought, and negative effects on grain filling and harvest index in some experiments compared with the control. When deep tillage with deep placement of manure was combined with mulching in two experiments in 2002 and 2003, grain yield always enhanced compared with the control (P < 0.10, 6.0 t ha−1 versus 5.4 t ha−1 on average), suggesting their synergetic mechanisms for yield increase and stabilization. The results showed that deep tillage or mulching can improve grain yield of rice under drought-prone rainfed upland conditions in a temperate climate on an Andosol, and their combination had more consistent and greater positive effects. 相似文献
52.
Preimplantation development of embryos in labrador retrievers 总被引:1,自引:0,他引:1
Abe Y Suwa Y Yanagimoto-Ueta Y Suzuki H 《The Journal of reproduction and development》2008,54(2):135-137
Preimplantation development of canine embryos is not well understood. To understand the timing of preattachment embryogenesis relative to the luteinizing hormone (LH) surge, early embryonic development was examined in Labrador Retrievers after artificial insemination. The embryos migrated from the oviduct to the uterus beginning on day 11 after the LH surge. This transport must be completed within 24 h. By day 13 after the LH surge, all of the embryos had moved and were localized in the uterus. The embryos developed to the morula stage within 11-13 days and to the blastocyst stage within 14 days after the LH surge, respectively. These findings add to the current understanding concerning the physiology of preimplantation development and should help further develop assisted reproductive techniques in canine species, such as cryopreservation and subsequent embryo transfer. 相似文献
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K Takehana M Abe K Iwasa T Hiraga 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(5):909-915
Complex carbohydrates were examined in glandular cells of the horse duodenal gland by using lectin histochemical techniques. In the horse, the duodenal gland was distributed in the area from the uppermost part of the small intestine to a point about 6m caudal to the pylorus. It consisted of two types of cells, mucous and serous cells. The former was found in glands distributed almost all over this part, but the latter was present in glands distributed restrictedly to the uppermost part of the small intestine at a point about 10 cm caudal to the pylorus. The cytoplasm of the mucous cell contained neutral glycoproteins with different saccharide residues as alpha-D-mannose, N-acetyl-beta (1----4)-D-glucosamine, galactose, alpha-galactose, alpha-N-acetylglucosamine, beta-D-Gal (1----3)-D-GalNAc, alpha-L-fucose and sialic acid. On the other hand, the serous cell contained neutral and acid glycoproteins with different residues such as alpha-D-mannose, alpha-D-glucose, beta-D-galactose(1----3)-D-N-acetylgalactose, alpha-L-fucose, N-acetyl-alpha-D-galactosamine, N-acetyl-beta (1----4)-D-glucosamine, galactose, alpha-galactose, alpha-N-acetylglucosamine and sialic acid. It is also elucidated in the present study that lipase, an enzyme for digestion, is contained in the serous cell of the equine duodenal gland. 相似文献
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To identify regions of the caprine diencephalone and pituitary gland related to transportation stress, the expression of c-fos protein was examined immunohistochemically as an indicator of neural activation. Ten castrated Shiba goats (Capra hircus), five transported and five controls, were used. Transported goats were trucked for 1 h and killed by transcardiac perfusion 1 h after the end of transportation. Control goats were housed in single pens killed in the same manner and at the same time as the transported goats. The diencephalon and the pituitary gland were removed after perfusion and used for immunostaining. Plasma cortisol concentrations during and after transportation also were investigated. During transportation, plasma cortisol concentrations increased (P < 0.05) compared with those in the controls. In the diencephalon, c-fos immunoreactive cells were detected in the subcallosa, the lateral septal area, the bed nucleus of stria terminalis (BNST), the preoptic hypothalamic area (POA), the suprachiasmatic nucleus (SCN), the supraoptic nucleus, the paraventricular hypothalamic nucleus parvocellular (PVNp), the paraventricular hypothalamic nucleus magnocellular (PVNm), the arcuate nucleus (ARC), the paraventricular thalamic nucleus, and the stria medullaris in both control and transported goats. The numbers of c-fos immunoreactive cells were increased (P < 0.05) by transportation in the PVNm, the PVNp, the BNST, the POA, the ARC, and the SCN (P < 0.10). In the anterior pituitary gland, the number of c-fos immunoreactive cells in transported goats was 4 to 30 times as much as in control goats; however, there were no differences in the intermediate and posterior lobes between control and transported goats. This study has identified regions in the caprine diencephalon and pituitary gland that show transport-induced increases in c-fos immunoreactive cells. In conclusion, the PVNm, the PVNp, the BNST, the POA, the SCN in the diencephalons, and the anterior lobe of pituitary gland may be involved in the stress responses of goats to transportation. 相似文献
59.
Full-length canine HSP70 cDNA was sequenced and the expression of HSP70 mRNA was investigated. The full-length cDNA sequence of the HSP70 gene (2322 bp) contained a single long open reading frame (1920 bp) coding a protein of 640 amino acids. The amino acid sequence of the canine HSP70 gene shared about 90-95% sequence similarity with bovine, human and mouse HSP70 proteins. Southern blot analysis with HSP70 probe gave three distinct bands of 9.4 kb, 5 kb and 4.4 kb in BamHI digests and two distinct bands of 19 kb and 4 kb in EcoRI digests. Canine HSP70 mRNA was detectable in canine peripheral blood mononuclear cells and stomach but not in liver, kidney, spleen, small intestine, large intestine and skin of dogs. 相似文献
60.
Ohtsuka H Watanabe C Kohiruimaki M Ando T Watanabe D Masui M Hayashi T Abe R Koiwa M Sato S Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(11):1161-1166
To clarify the relationship between cellular immune status and nutritive condition in periparturient dairy cows, feeding content, blood profiles, and immune condition were observed in cows from two dairy herds with different types of feed content. Immunological analyses such as leukocyte population and peripheral blood mononuclear cell (PBMC) mRNA of IFN-gamma, TNF-alpha, IL-4, and IL-10, quantified by real-time RT-PCR were performed. With regard to feed content during dry periods, there were six cows in the herd with insufficient non-structural carbohydrate (NFC) intake (group I) and six cows in the herd with sufficient NFC intake (group II). Significantly lower levels of blood glucose were observed in group I between weeks -12 and 16 compared with group II. Serum cholesterol level was significantly lower in group I between weeks 2 and 10 than in group II. The numbers of CD3+ and CD4+ T cells in group I were significantly lower than those in group II in weeks 6 and 14. The numbers of CD21+ B cells were significantly lower in group I than in group II in weeks -16, -12, 2, and 10. On the other hand, the CD4+/CD8+ ratio in group II was significantly higher than group I between weeks 2 and 14. The IFNgamma/IL-4 mRNA rate in group I was significantly lower than group II in week 6. We concluded that cellular immune depression occurrs after calving in dairy cows with low nutritional status in the periparturient period. 相似文献