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1.
Yoshimichi GODA Shinya MIZUTANI Yuko MIZUTANI Go KITAHARA Riki SISWANDI Kenta WAKABAYASHI Shidow TORISU Yasuyuki KANEKO Yuichi HIDAKA Takeshi OSAWA Taketoshi ASANUMA Reiichiro SATO Hiroyuki SATOH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(10):1430
Cryptorchidism is defined as the failure of the testis to descend into the scrotal position. Bulls with cryptorchidism have problems in both meat quality and husbandry management; thus, it is greatly important to accurately identify the retained testis and remove it during the early stage. Abdominal computed tomography (CT) was performed under general anesthesia in 34 bulls aged 3–9 months with cryptorchidism. All bulls underwent laparoscopic or incision approach for cryptorchidectomy, and 40 testes were dissected. The detection rates of retained testes were 64.5% in the abdominal cavity and 100% in the subcutaneous inguinal region, and the total detection rate was 72.5%. Furthermore, all cases in this study were suspected to have intra-abdominal cryptorchidism in primary care, but CT revealed that 22.5% of cases had cryptorchidism in the subcutaneous inguinal region. The CT value (mean ± standard deviation) of the retained testes was 20.96 ± 7.54 Hounsfield Unit, and the CT value and size of the retained testes showed a positive weak correlation with bovine age. Therefore, there is the demerit that general anesthesia and a huge device are necessary; nevertheless, CT is suggested to be useful in identifying the location of retained testes and selecting an appropriate surgical approach in bulls with cryptorchidism. Moreover, CT findings suggested that the maturation of the retained testes might depend not on the descending process but on age. 相似文献
2.
Noriyuki Koizumi Atsushi Mori Takuya Mineta Eiji Sawada Keiji Watabe Takeshi Takemura 《Paddy and Water Environment》2017,15(4):723-730
Fecal DNA samples from the red-eared slider and Reeves’ pond turtle, suspected pests of lotus root paddies, were used to identify the plant species eaten by these turtles in order to develop a strategy for rural ecosystem conservation. The fecal samples were obtained from young and adult individuals (mostly female) of both species living in agricultural canals surrounding lotus root paddies in Tokushima Prefecture, Japan. The samples were screened for the presence or absence of DNA from nine plant species using PCR and plant species-specific primers for the rbcL gene of chloroplast DNA. In the red-eared slider, our analysis identified seven plant species in the fecal DNA samples of adults and three plant species in those of young individuals. In Reeves’ pond turtle, our analysis identified two plant species from adult fecal samples and one species from those of young individuals. Thus, adult red-eared sliders consume a greater range of plants than young red-eared sliders or Reeves’ pond turtles. Both turtle species, independently of age, consumed lotus plants and were likely to cause feeding damage to lotus roots. Considering the plant species detected in adult red-eared sliders and these plant habitats, we suggest that this adult turtle is likely to travel between the agricultural canals and the lotus root paddies. These findings will help the development of strategies for preventing damage to lotus roots by these turtles; furthermore, they indicate that fecal DNA analysis will be applicable to investigation of the feeding habits of other animal species. 相似文献
3.
Hiroshi UENO Osamu YAMATO Takeshi SUGIURA Moeko KOHYAMA Akira YABUKI Kenjiro MIYOSHI Kazuya MATSUDA Tsuyoshi UCHIDE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):91-95
A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed
progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors,
visual disorder and seizure after 4 months of age. Finally, the cat died of neurological
deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes
had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical
hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on
T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of
the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in
leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis.
Histologically, swollen neurons characterized by accumulation of pale, slightly granular
cytoplasmic materials were observed throughout the central nervous system. Dysmyelination
or demyelination and gemistocytic astrocytosis were observed in the white matter.
Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons.
However, genetic analysis did not identify the c.1448G>C mutation, which is the single
known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a
new variant of the feline disease. 相似文献
4.
Effect of bamboo vinegar on regulation of germination and radicle growth of seed plants 总被引:10,自引:0,他引:10
Two kinds of bamboo vinegar from madake bamboo (Phyllostachys bambusoides) and moso bamboo (Phyllostachys pubescens) were prepared to analyze their components by gas chromatography (GC). The original vinegar, distilled vinegar, ether-extracted
vinegar, and three fractions including acidic, neutral, and phenolic fractions separated from ether-extracted vinegar were
diluted with distilled water 102 to 107 times. These diluted vinegar solutions were used to investigate the effect of bamboo vinegar on the germination and radicle
growth of seed plants. High concentrations of all kinds of treated bamboo vinegars (e.g., 102 of original vinegar and 103 of ether-extracted vinegar) showed strong inhibition against germination of the seeds. However, an appropriate dilution of
bamboo vinegar showed an obvious promotional effect on germination and radicle growth for the four kinds of tested seeds (lettuce,
watercress, honewort, chrysanthemum).
Received: December, 12, 2001 / Accepted: July 29, 2002
RID="*"
ID="*" Part of this paper was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 相似文献
5.
Hitoshi Kaneko Takeshi Okunishi Takashi Seto Hiroshi Kuroda Sachihiko Itoh Shinya Kouketsu Daisuke Hasegawa 《Fisheries Oceanography》2019,28(2):212-227
To clarify the effects of temperature on the recruitment of chub mackerel (Scomber japonicus) in the North Pacific, we investigated the influence of winter surface temperature (WST) on spawners at the time of maturity around the spawning grounds and the influence of ambient spring temperature on larvae using estimated temperature (ET) obtained from particle tracking experiments. We found a significant positive correlation between ET approximately 10 days following hatching and the recruitment per spawning stock biomass (RPS) after 2000. The closer (more meandering) the Kuroshio Current (KC) axis was in relation to the spawning ground, the higher (lower) the spring surface temperature and the higher (lower) RPS was in the spawning ground. In contrast, WST inside KC near the maturity/spawning ground was significantly negatively correlated with RPS. A significant negative correlation between the temperatures in winter and spring was detected in the area after 2000, when the conditions of the Pacific decadal oscillation index and the stability of the Kuroshio Extension were synchronous, indicating that KC shifted northward during this time. The reversed temperature pattern was consistent with the winter–spring movement of KC axis in the offshore direction and was correlated with the winter–spring difference in the intensity of the Aleutian low. These results suggest that the annual variation in chub mackerel recruitment after 2000 was strongly affected by the combined effects of ambient temperature because of the reversal of conditions that occurred between winter and spring around the maturity/spawning ground, which was related to the KC path. 相似文献
6.
Spermatogenesis and its endocrine regulation 总被引:2,自引:2,他引:2
Three major phases compose spermatogenesis: mitotic proliferation of spermatogonia, meiosis of spermatocytes, and spermiogenesis,
the restructuring of spermatids into flagellated spermatozoa. The process is fuelled by stem cells that, when dividing, either
self-renew or produce spermatogonia that are committed to proliferation, meiosis, and spermiogenesis. During all phases, germ
cells are in close contact with and require the structural and functional support of Sertoli cells. In contrast to germ cells,
these somatic cells express receptors for sex steroids and follicle-stimulating hormone (FSH), the most important hormones
that regulate spermatogenesis. A typical Sertoli cell response to an endocrine stimulus would be to change the release of
a growth factor that would then mediate the hormone's effect to the germ cells. Recent studies in the Japanese eel have shown,
for example, that in the absence of gonadotropin Sertoli cells produce a growth factor (an orthologue of anti-Müllerian hormone)
that restricts stem cell divisions to the self-renewal pathway; also estrogens stimulate stem cell renewal divisions but not
spermatogonial proliferation. Gonadotropin or 11-ketotestosterone (11-KT) stimulation, however, induces spermatogonial proliferation,
which is in part mimicked by another Sertoli cell-derived growth factor (activin B). Since FSH (besides luteinizing hormone,
LH) stimulates steroidogenesis in fish, and since FSH is the only gonadotropin detected in the plasma of sexually immature
salmonids, increased FSH signalling may be sufficient to initiate spermatogenesis by activating both Sertoli cell functions
and 11-KT production. Another important androgen is testosterone (T), which seems to act via feedback mechanisms that can
compromise FSH-dependent signalling or steroidogenesis. The testicular production of T and 11-KT therefore needs to be balanced
adequately. Further research is required to elucidate in what way(s) 11-KT stimulates later stages of development, such as
entry into meiosis and spermiogenesis. At this period, LH becomes increasingly important for the regulation of androgen production.
Results from mammalian models suggest that during the later phases, the control of germ cell apoptosis via Sertoli cell factors
is an important regulatory mechanism. In many species, sperm cells cannot fertilize eggs until having passed a maturation
process known as capacitation, which includes the acquisition of motility. Progestins that are produced under the influence
of LH appear to play an important role in this context, which involves the control of the composition of the seminal plasma
(e.g., pH values).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Shinichiro Ogawa Makoto Kimata Masamitsu Tomiyama Masahiro Satoh 《Journal of animal science》2022,100(3)
We estimated heritabilities of semen production traits and their genetic correlations with litter traits and pork production traits in purebred Duroc pigs. Semen production traits were semen volume, sperm concentration, proportion of morphologically normal sperms, total number of sperm, and total number of morphologically normal sperm. Litter traits at farrowing were total number born, number born alive, number stillborn, total litter weight at birth, mean litter weight at birth, and piglet survival rate at birth. Litter traits at weaning were litter size at weaning, total litter weight at weaning, mean litter weight at weaning, and piglet survival rate from birth to weaning. Pork production traits were average daily gain, backfat thickness, and loin muscle area. We analyzed 45,913 semen collection records of 896 boars, 6,950 farrowing performance records of 1,400 sows, 2,237 weaning performance records of 586 sows, and individual growth performance records of 9,550 animals measured at approximately 5 mo of age. Heritabilities were estimated using a single-trait animal model. Genetic correlations were estimated using a 2-trait animal model. Estimated heritabilities of semen production traits ranged from 0.20 for sperm concentration to 0.29 for semen volume and were equal to or higher than those of litter traits, ranging from 0.06 for number stillborn and piglet survival rate at birth to 0.25 for mean litter weight at birth, but lower than those of pork production traits, ranging from 0.50 for average daily gain to 0.63 for backfat thickness. In many cases, the absolute values of estimated genetic correlations between semen production traits and other traits were smaller than 0.3. These estimated genetic parameters provide useful information for establishing a comprehensive pig breeding scheme. 相似文献
8.
Fumitaka Kondo Takashi Ohta Toshiharu Iwai Atsushi Ido Chiemi Miura Takeshi Miura 《Fish physiology and biochemistry》2017,43(6):1543-1555
The improvement in feed efficiency is one of the most important subjects in fish culture. The development of feed, in terms of good intake, high growth performance, and high feed efficiency is needed. Squid viscera are one of the candidates for alternative material in improving feed efficiency in fish culture. In the present study, we described the dietary effect of the squid viscera hydrolysate (SVH) on the growth performance of the red sea bream. The addition of SVH to feed caused significant increases in feed intake, fork length, and body weight and produced a marked improvement in feed conversion after 4 weeks of feeding. Furthermore, the results of this feeding revealed that low dietary levels of SVH promote growth performance in the red sea bream. We physiologically analyzed digestion and appetite in fish fed diet containing SVH. SVH promoted the activity of hepatic trypsin and lipase, gene expression of stomach pepsin, hepatic lipase, and pyloric caeca trypsin, thereby improving the nutrient availability in red sea bream. Moreover, the mRNA expression of appetite regulating factor, such as brain NPY and stomach ghrelin was significantly improved by dietary SVH. Our current results indicate that dietary SVH as alternative material produced excellent effects on growth performance, which is dependent on the promoting effect on digestion and appetite in red sea bream. 相似文献
9.
ABSTRACT: Sporophyll formation in two alariaceous plants, Undaria pinnatifida and Alaria crassifolia , was studied in relation to the nutrient requirements. The sporophylls of U. pinnatifida formed zoosporangia when they had N and P contents greater than 1.4 kgN/m3 and 0.74 kgP/m3 . This indicates that these values are the critical nutrient levels for zoospore formation in U. pinnatifida . In the sporophytes of A. crassifolia , many sporophylls with zoosporangia showed nutrient contents higher than 6.25 kgN/m3 and 1.70 kgP/m3 . These results suggest that the U. pinnatifida can form zoospores at lower levels of N and P contents than A. crassifolia . Both species often formed zoosporangial sori on the blades in the late period of each reproductive season. The fertile parts of the blade showed N and P contents higher than the critical levels. This phenomenon indicates that the blades have the capability to form zoosporangial sori if there is a sufficient accumulation of nutrients for zoospore formation. The zoospore formation on the blade seems to be accomplished by an overflow of excess nutrients from sporophylls into the blade, or by accumulating sufficient nutrients to form sori even if the sporophylls are not formed. 相似文献
10.
Edgar C Amar Viswanath Kiron Shuichi Satoh Nobuaki Okamoto and Takeshi Watanabe 《Fisheries Science》2000,66(6):1068-1075
SUMMARY: We attempt to assess the impact of different levels of dietary β-carotene on immune function in rainbow trout. Semi-purified diets containing 0, 40, 200, and 400 mg β-carotene/kg dry diet were fed for 12 weeks to fish with average weight of 45 g. In addition to the humoral and cellular immune parameters, growth and feed utilization were examined. There were no marked differences in growth and feed utilization showing that β-carotene was not particularly efficient in enhancing growth of rainbow trout. Of the immune parameters measured, total immunoglobulin was significantly highest for the 200 mg β-carotene fed group. Serum complement activity (alternate pathway) at 200 and 400 mg β-carotene supplementation was significantly higher than that of the unsupplemented group. An increasing trend in lysozyme activity was observed, however, the differences among the groups were not significant. Phagocytic activity was similar among diet groups except at the highest level of supplementation where it was the maximum. Oxygen radical production by peripheral blood leukocytes appeared to be lower at higher levels of carotenoid supplementation. Overall, dietary β-carotene clearly enhanced immune response parameters in rainbow trout such as serum complement activity and total plasma immunoglobulin but did not show a definite influence for the other factors examined in the present study. 相似文献