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31.
In this study, two following experiments were performed to improve post-thaw motility and viability of frozen-thawed ram spermatozoa. We examined i) the effects of different concentrations of bovine serum albumin (0, 0.3, 1, 5, 10 and 15% BSA) in semen diluents lacking egg yolk and ii) the effects of four semen diluents, fructose (F: control) and trehalose (T) in semen diluents containing egg yolk, 15% BSA in semen diluents without egg yolk (BSA), and modified phosphate buffered saline (m-PBS). Frozen-thawed spermatozoa were examined for progressive sperm motility, viability, morphological abnormality, sperm tail swelling test, and sperm acrosome integrity. In Experiment 1, the rates of sperm motility immediately after thawing (0 h) were significantly (P<0.05) higher in the 10 and 15% BSA groups (55.0 +/- 2.9 and 58.3 +/- 6.7%, respectively) than in the positive control (F) group (41.7 +/- 4.4%). The rate of sperm viability in the negative control (0% BSA) group (80.2 +/- 3.3%) was significantly (P<0.05) lower than in the positive control (F) group (89.8 +/- 1.5%), but when compared with the F group, no significant differences were found among the 0.3, 1, 5, 10 and 15% BSA groups at 0 h. The rates of sperm morphological abnormality of the 10 and 15% BSA groups (6.5 +/- 1.3 and 6.3 +/- 1.1%, respectively) were significantly (P<0.05) lower at 0 h than that in the 1% BSA group (16.3 +/- 5.2%). In Experiment 2, T addition improved (P<0.05) the post-thaw motility compared with the F and BSA groups. Furthermore, at 3 and 6 h, the post-thaw motility of the T group (36.3 +/- 2.4 and 25.0 +/- 2.0%, respectively) was significantly (P<0.05) higher than in the BSA (26.3 +/- 2.4 and 18.8 +/- 1.3%, respectively) and F (28.8 +/- 3.8 and 18.8 +/- 2.4%, respectively) groups. The post-thaw sperm motility and viability in the m-PBS group were significantly (P<0.05) lower than those of the control (F), T, and BSA groups throughout all observation points. These results indicate that 10 and 15% BSA can be substituted for egg-yolk for ram semen diluent and that the addition of trehalose enhances motility and viability of ram spermatozoa after freezing and thawing. 相似文献
32.
Matsuoka T Imai H Asakuma S Kohno H Fukui Y 《The Journal of reproduction and development》2006,52(6):805-810
The present study was performed to examine seasonal changes in the fructose concentrations of seminal plasma and glucose and testosterone concentrations of blood plasma over the course of a year (from November 2004 to November 2005) using 5 Suffolk rams. Osmolality of the seminal plasma was also measured. The fructose concentrations in the seminal plasma increased as the breeding season approached, with the maximum in October (179.8 mg/dl) and the minimum in May (6.9 mg/dl), although there were no significant differences during the year. Osmolality of the seminal plasma in February (304 mOsm) was significantly (P<0.05) lower than in January (325 mOsm), July (327 mOsm), and August (325 mOsm). It was also significantly (P<0.05) lower in November (308 mOsm) than in January and August. The blood plasma glucose concentration in October (79.3 mg/dl) was significantly (P<0.05) higher than in January and February (43.2 and 43.7 mg/dl, respectively). The blood plasma testosterone (T) concentrations were significantly (P<0.05) higher in September (8.5 ng/ml) and October (10.2 ng/ml) than in other months. The fructose concentrations in the seminal plasma appeared to be related to the glucose and T concentrations in the blood plasma. These results show that fructose concentrations in the seminal plasma and blood plasma glucose and T concentrations tended to increase during the breeding season, with the highest concentrations in October. 相似文献
33.
34.
Kanno N Asano K Teshima K Seki M Edamura K Uechi M Tanaka S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(6):739-743
Adrenomedullin (AM), a peptide identified to have vasodilating and natriuretic effects, is involved in the regulation of the cardiovascular system. To evaluate plasma AM concentration in dogs with myxomatous mitral valvular disease (MMVD), and to investigate the associations between the concentrations of plasma AM and natriuretic peptides and the echocardiographic data, we evaluated plasma AM concentrations in 31 healthy control dogs and 57 dogs with MMVD. Plasma AM concentrations in dogs with MMVD were higher than that in the control subjects. The plasma AM concentration increased in conjunction with the severity of heart failure according to the International Small Animal Cardiac Health Council (ISACHC). The AM concentrations were 25.1 ± 5.0 fmol/ml (ISACHC class Ia), 29.9 ± 11.0 fmol/ml (ISACHC class Ib), 43.4 ± 19.8 fmol/ml (ISACHC class II) and 73.5 ± 21.7 fmol/ml (ISACHC class III) and 7.5 ± 5.1 fmol/ml (control group), respectively. The receiver operating characteristic curve indicated an area of 0.93 (95% CI, 0.8801-0.9889; <0.0001), a cutoff value of 30.5 fmol/ml, a sensitivity of 87.1%, and a specificity of 82.5% for the determination of congestive heart failure. Plasma AM concentrations correlated with atrial natriuretic peptide concentrations, LA/Ao ratio, and left ventricular diameter. In conclusion, AM may be a potential diagnostic marker for canine MMVD and possibly plays a pathophysiological role in collaboration with the other neurohumoral factors such as natriuretic peptides. 相似文献
35.
Makoto?Watanabe Masahiro?Yamaguchi Hideyuki?Matsumura Yoshihisa?Kohno Takeshi?IzutaEmail author 《European Journal of Forest Research》2012,131(2):475-484
Tropospheric ozone (O3) is considered to be the air pollutant relating to the decline of Fagus crenata forest in Japan. In the present study, we assessed a risk of O3 impact on the growth of F. crenata in Japan, giving consideration to the effects associated with atmospheric nitrogen (N) deposition based on the experimental
study, national monitoring data for oxidant concentration and atmospheric N deposition, and a national vegetation survey.
The average and maximum O3-induced relative growth reduction (RGred) of F. crenata across Japan were estimated to be 3.2 and 9.7%, respectively. Current levels of atmospheric N deposition were found to significantly
affect the sensitivity of F. crenata to O3. When the N deposition was assumed as zero, the estimated average and maximum RGred were 2.3% and 5.7%, respectively. The inclusion of atmospheric N deposition data thus increased the estimated values for
average and maximum RGred (by 38% and 71%, respectively). Our results demonstrate that a change in the sensitivity to O3 associated with atmospheric N deposition is an important consideration in the risk assessment of O3 impact on the growth of F. crenata in Japan. 相似文献
36.
Ninomiya H Inomata T Kanemaki N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(9):887-892
The microvasculature of the eyes of 5 rabbits was investigated using scanning electron microscopy on corrosion casts. The study revealed that the pars plana vessels draining blood from the iris and ciliary body coursed directly into the anterior vortex venous system constituting the scleral venous plexus (the venous circle of Hovius). The episcleral vasculature was found to possess a specialized morphology, with channels draining the aqueous humor. The capillaries of the third palpebral, bulbar and palpebral conjunctiva formed a single-layered capillary network approximately parallel to the epithelium and formed a well-developed venous plexus in the stroma. The retina was found to be merangiotic, meaning that vessels were present only in a small part of the retina, extending in a horizontal direction to form bands on either side of the optic disc. Channels representing the aqueous veins that drained blood mixed with aqueous humor were found to derive directly from the suprachoroidal space and communicate with the scleral venous plexus via the anterior vortex veins. The functional significance of the microvasculature of the iris, cilia, retina and choroid is discussed in this report as well. The elaborate microvasculature of the conjunctiva may be a prerequisite for the exchange of nutrients and gasses between the cornea and the vessels across the conjunctival epithelium when the eyelids are shut during sleep, and possibly for the dynamics of eye drop delivery. The scleral venous plexus in rabbits may be analogous to the scleral venous sinus (Schlemm's canal) in rats, primates and humans. 相似文献
37.
Eiji Hayashi Kazuya Iizuka Shin-ichi Sukeno Kohzo Kohno 《Journal of Forest Research》1998,3(2):119-122
We determined the survival rate of tree families produced by the intra- and interspecific crossing of larch species damaged
by browsing of vole (Clethrionomys rufocanus bedfordiae Thomas) and the contents of ether extracts (EE) in their bark. The average survival ofLarix gmelini var.japonica Pilg. (L. gmelini)×L. gmelini (G×G) was highest, followed by the hybridL. gmelini×L. leptolepis Gordon (G×L). The families of the hybrid G×L, which is considered suitable for silviculture in Hokkaido, Japan, showed significant
differences in survival rates, suggesting that it is possible to produce improved varieties of the hybrid which are more resistant
to vole browsing. The EE contents of the bark were under strong hereditary control, and the rank of the EE content among the
various families hardly fluctuated between the location of the test fields. The correlation coefficient between the survival
rates and the EE contents was highly significant (r=0.89,n=24,p<0.01), indicating that the EE content in the bark may be used as a possible index of resistance or susceptibility to vole
browsing in larch plantations.
A part of this report was presented at the 106th Annual Meeting of the Japanese Forestry Society, at Sapporo, April, 1995. 相似文献
38.
Yutaro Sakai Nobuyuki Yagi Masahiko Ariji Atsushi Takahara Hisashi Kurokura 《Fisheries Science》2009,75(5):1079-1087
A demand system analysis was conducted to examine the substitute relationships between tuna and skipjack tuna in the Japanese
market. Data from the Annual Report on Family Income and Expenditure Survey from 1965 to 2006 were used for the analysis using
the almost ideal demand system (AIDS). Results suggest that skipjack tuna can be a strong substitute for tuna, while other
fish groups are not a clear substitute. Our analysis of substitute relationships among fish species in a market indicates
that this is a factor that should be considered for better fisheries resource management. For instance, even under a situation
where one fish species is underexploited, proper attention to its fishery management is necessary if the fish is a strong
substitute for another popular fish species in the market. 相似文献
39.
Masaru Fujinoki Tomoko Koito Suguru Nemoto Mitsugu Kitada Yoko Yamaguchi Susumu Hyodo Hideki Numanami Nobuyuki Miyazaki Koji Inoue 《Fisheries Science》2012,78(1):139-146
Various invertebrates inhabiting hydrothermal vents harbor thiotrophic endosymbionts that provide the host with nutrients
and are possibly involved in the detoxification of harmful sulfides. In this study, we first determined the partial 16S rRNA
gene sequence of the thiotrophic symbiont of the deep-sea mussel Bathymodiolus septemdierum, a dominant species at hydrothermal vents in the Izu–Ogasawara (Bonin) area. We then designed a new probe, Bsob692, for fluorescent in situ hybridization (FISH) using regions completely conserved among thiotrophic symbionts of all
bathymodiolin mussels and established the protocol for FISH to compare the distribution and amount of the symbiont using an
image analysis program that is commercially available. We compared fluorescent intensity in the gill of the mussels collected
at different sites and found a higher intensity in specimens collected from a site with higher sulfide concentration. We also
compared mussels reared in the presence and absence of sulfide and found that the former had a higher fluorescent intensity. 相似文献
40.
Nobuyuki Fukuoka 《The Journal of Horticultural Science and Biotechnology》2013,88(4):456-460
SummaryEarly sown radish seedlings were subjected to heat stress from the middle to late growth stage. Roots exhibiting internal browning (IB) were more prevalent in the susceptible cultivars whose seeds were sown early in the summer compared with those which were sown late. However, IB occurrence in the resistant ones was not nearly so marked regardless of the sowing date. In the IB susceptible cultivars, higher levels of L-phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) activities were detected in roots from the early sown plot (ESP), but these enyzme inductions did not occur to a significant extent in the resistant ones. Roots suffering internal browning were also detected to have pronounced increases in ascorbate peroxidase (APX) activity, but decreases in both dehydroascorbate reductase (DHAR) and glutathione reductase (GHAR) activities. These observations strongly suggest that a decline in H2O2 decomposing capacity of the ascorbate-glutathione cycle by heat stress is responsible for the activation of H2O2 detoxyifying pathway derived from PPO. 相似文献