Artificial insemination with frozen epididymal sperm in cats     

Tsutsui T  Wada M  Anzai M  Hori T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(3):397-399

Artificial insemination with frozen cauda epididymal sperm was performed in cats. Sperm were transmigrated from the epididymides in 10 male cats. The mean sperm motility and viability were 67% and 82.5%, respectively, and 11.6 x 10(7) sperm were recovered. The mean sperm motility after thawing was 24.0%. Eleven female cats received unilateral intrauterine insemination of 5 x 10(7) sperm, and the conception rate was 27.3% (3/11). This was the first case of conception obtained with frozen epididymal sperm in cats.  相似文献   

Frequency-dependent natural selection in the handedness of scale-eating cichlid fish     

Hori M 《Science (New York, N.Y.)》1993,260(5105):216-219

Frequency-dependent natural selection has been cited as a mechanism for maintaining polymorphisms in biological populations, although the process has not been documented conclusively in field study. Here, it is demonstrated that the direction of mouth-opening (either left-handed or right-handed) in scale-eating cichlid fish of Lake Tanganyika is determined on the basis of simple genetics and that the abundance of individuals with left- or right-handedness depends on frequency-dependent natural selection. Attacking from behind, right-handed individuals snatched scales from the prey's left flank and left-handed ones from the right flank. Within a given population, the frequency of the two phenotypes oscillated around unity. This phenomenon was effected through frequency-dependent selection exerted by the prey's alertness. Thus, individuals of the rare phenotype had more success as predators than those of the more common phenotype.  相似文献   

Spatial variation of quantitative color traits in green and black types of sea cucumber <Emphasis Type="Italic">Apostichopus japonicus</Emphasis> (Stichopodidae) using image processing     

Katsumasa Yamada  Masakazu Hori  Susumu Matsuno  Tatsuo Hamano  Masami Hamaguchi 《Fisheries Science》2009,75(3):601-610

It has been suggested that the Japanese sea cucumber, Apostichopus japonicus, has three color types (red, green, and black), although the qualitative difference between the color types, particularly between the green and black types, is unclear because of continuous color variation among color types. This study elucidated the color variation between green and black types using image processing (RGB, red–green–blue system) and multivariate analysis to demonstrate whether or not the black and green types can be quantitatively classified. Moreover, spatial variation of the RGB value among various local sites was clarified to estimate potential environmental factors that may affect the color variation. The series of analyses revealed that a quantitative boundary between green and black types could be provisionally established, and also that spatial variability in the intermediate (continuous) color trait between green and black types was significant. Potential environmental factors (depth and industrial activity index) were correlated with the color traits in both color types. These results suggest that the green and black types cannot be regarded as independent color traits and that the color variation between green and black types may be influenced by local environmental factors.  相似文献   

Seagrass habitat reduces vulnerability of red sea bream <Emphasis Type="Italic">Pagrus major</Emphasis> juveniles to piscivorous fish predator     

Jun Shoji  Kazutaka Sakiyama  Masakazu Hori  Goro Yoshida  Masami Hamaguchi 《Fisheries Science》2007,73(6):1281-1285

ABSTRACT:   Predation experiments were conducted in mesocosms to test the hypothesis that habitat complexity affects vulnerability of red sea bream Pagrus major juveniles to piscivorous fish predators. Juvenile behavior was video-recorded for 6 h in two structurally different habitats: vegetated with sea grass Zostera marina , and unvegetated 0.5-t tanks. Association behavior with seagrass was observed in the vegetated tank throughout the trials. Predation experiments were conducted with 30 red sea bream juveniles (29.9 mm body length) exposed to two individuals of the piscivorous fish predator Chinese sea bass Lateolabrax sp. (261.6 mm), for 6 h in 1.0-t tanks. Predation rate (no. of fish predated on per predator per h) was significantly lower in the vegetated tank (0.02/predator per h) than in the unvegetated tank (0.27/predator per h). Present experiments indicate that habitat complexity reduces vulnerability of juvenile red sea bream to predation by piscivorous fish by serving as physical and/or visual barriers and limiting the predator's ability to pursue and capture prey. Seagrass beds in the shallow coastal waters around Japan are suggested to be an important nursery for red sea bream since they provide the juveniles with habitat complexity as well as serve as a feeding ground.  相似文献   

Offshore currents explain the discontinuity of a fish community in the seagrass bed along the Japanese archipelago          下载免费PDF全文

Atsushi Fukuta  Yasuhiro Kamimura  Masakazu Hori  Masahiro Nakaoka  Tsutomu Noda  Yoh Yamashita  Tsuguo Otake  Jun Shoji 《Fisheries Oceanography》2017,26(1):65-68

Oceanographic conditions can affect spatial variability in fish community structures by influencing the temperature‐dependent latitudinal distribution of adult fishes and transport during their young stages. In order to examine latitudinal variability in the fish community structure within a single coastal ecosystem, quantitative sampling was conducted in the sub‐tidal zone of seagrass Zostera marina beds over a broad latitudinal scale (31.31–43.0°N: from subtropical to sub‐boreal zones, covering 80% of the latitudinal range of seagrass distribution in Japan) in the western North Pacific based on a uniform methodology. Cluster analysis with the similarity of fish communities showed that 13 sampling sites were divided into two clusters. The border between the two clusters corresponded with the area of mixing of two dominant currents, Oyashio and Kuroshio, which form a border between the warm temperate zone and the cool temperate zone off the Pacific coast of Japan. Oceanographic properties, such as major currents off the coast, are suggested to affect the latitudinal variability in the fish communities in the coastal ecosystem in the western North Pacific.  相似文献   

Studies on the cholinesterase of the chicken. II. Substrate specificity of true cholinesterase and distribution of cholinesterase types in tissues     

A Tanabe  S Hori  T Toriumi  M Ikeda 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1971,33(3):111-120

  相似文献   

Transfer of canine embryos at various developmental stages recovered by hysterectomy or surgical uterine flushing   总被引：4，自引：0，他引：4  

Tsutsui T  Hori T  Okazaki H  Tanaka A  Shiono M  Yokosuka M  Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):401-405

In dogs, embryo transfer (ET) techniques such as induciton of excessive ovulation and synchronization of estrus have not progressed well. Therefore, using embryos at various developmental stages, ET was investigated in dogs from a beagle colony in which the ovulation days were close, as estimated by the progesterone level. Embryos were, recovered 8-11 days after ovulation (4-9 days after mating) by excising the oviducts and uteri (excision method) in 16 animals and by surgical flushing of the uteri at laparotomy (surgical method) in 3 animals. In 24 dogs with -4 to +2 days of difference in the timing of ovulation between donor and recipient dogs, 1-10 embryos at the 8-cell to blastocyst stages were transferred per animal. The mean embryo recovery rate by the excision method (97.1%) was significantly higher than that by the surgical method (42.5%) (p<0.01). Twelve (57.1%) of 21 animals with -1 to +2 days difference in ovulation day became pregnant after the transfer of 8-cell to blastocyst stage embryos. Although 3 dogs with -4 to -2 days of difference of ovulation day underwent ET of morula or compacted morula, none of these dogs became pregnant. The mean ratio of the number of newborns to the number of transferred embryos was only 51.9%. The mean duration of the period between ovulation and delivery in the pregnant recipients was 65.8 days, which tended to be longer than that in natural mating. These results demonstrate that pregnancy can be induced by ET at the 8-cell to blastocyst stage in dogs with -1 to +2 days difference in ovulation day.  相似文献   

Effect of osaterone acetate administration on prostatic regression rate, peripheral blood hormone levels and semen quality in dogs with benign prostatic hypertrophy     

Tsutsui T  Hori T  Shimizu M  Tatsuzawa C  Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(4):453-456

The effects of osaterone acetate (OSA), which is an anti-androgen agent being developed as a therapeutic drug for benign prostatic hypertrophy (BPH) in dogs, on the degree of prostatic regression and semen qualities were investigated. Prostatic regression was compared between dogs with and without orchidectomy. Five male beagles aged 5-9 years were used in the experiment. OSA was orally administered at doses of 0.2 mg/kg and 0.5 mg/kg for one week. The prostatic regression rate one week after the end of administration was 62.6% on average. In the orchidectomized group, the mean regression rate one week after orchidectomy was 60.1%. However, the prostate became enlarged 6 months after administration, compared to the size prior to administration. The above findings suggested that OSA is clinically applicable as a therapeutic drug for BPH in dogs, and inhibits prostatic hypertrophy during the early phase.  相似文献   

Intrauterine and intravaginal insemination with frozen canine semen using an extender consisting of orvus ES paste-supplemented egg yolk tris-fructose citrate     

Tsutsui T  Hase M  Tanaka A  Fujimura N  Hori T  Kawakami E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(6):603-606

Our previous report indicated that addition of Orvus ES Paste (OEP) to the extender of frozen canine semen protected acrosomes and maintained sperm motility after thawing. In this study, artificial insemination (AI) using the frozen semen was carried out. The frozen semen was prepared using egg yolk Tris-fructose citrate, and the final concentrations of glycerol and OEP were 7% (v/v) and 0.75% (v/v), respectively. AI was performed during the optimal mating period predicted from the peripheral plasma progesterone level. In intrauterine insemination (IUI), the bitches were laparotomized and 1 x 10(8) spermatozoa were infused into one of the uterine horns. In insemination of non-OEP supplemented semen, 3 x 10(8) spermatozoa were inseminated. In intravaginal insemination (IVI), 10-40 x 10(8) spermatozoa were inseminated. Conception was obtained in nine of 10 bitches (90.0%) that underwent IUI. The number of newborns was from 1 to 7 (mean 3.6 +/- 0.9). The mean ratio of the number of puppies to the number of ovulations in the inseminated uterine horn was 71.8%. The number of puppies did not exceed the number of ovulation in the inseminated uterine horn. Conception using non-OEP supplemented frozen semen was unsuccessful in all four bitches. In IVI, conception was not obtained in any of the six bitches that received insemination of 10 x 10(8) or 40 x 10(8) spermatozoa, but two of three bitches that received insemination of 20 x 10(8) spermatozoa were fertilized. It was shown that a high conception rate can be obtained by IUI using OEP-supplemented frozen canine semen. Developmenmt of a non-surgical method of IUI and a method of freezing canine sperm applicable to IVI is necessary.  相似文献   

Unilateral intrauterine horn insemination of frozen semen in cats     

Tsutsui T  Tanaka A  Takagi Y  Nakagawa K  Fujimoto Y  Murai M  Anzai M  Hori T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2000,62(12):1247-1251

Frozen feline semen was prepared using two types of extenders, egg yolk Tris-fructose citric acid (EYT-FC) and egg yolk sodium citrate solution (EYC), and the semen qualities after thawing and the conception rates obtained by unilateral intrauterine horn insemination (UIUI) were investigated. Cats used in the experiment were six males and 11 females aged 2-12 years (the number of experimental cases was 17). For preparation of frozen semen, semen collected by the artificial vagina method was adjusted to I x 10(8) sperm/m/ and 7% glycerol, put in 250 microl straws, and then frozen using a cell freezer. The mean sperm motility after thawing was 30.0+/-9.7 (SE) % in the semen prepared with EYT-FC and 30.0+/-3.3% in the semen prepared with EYC. Four of seven animals were fertilized by UIUI using two straws in both extenders, and the conception rate was 57.1%. The mean ratios of number of kits to the number of ovulations in the inseminated side were 61.1+/-24.5% and 30.5+/-3.4% for EYT-FC and EYC, respectively, showing that the ratio tended to be higher in the semen prepared with EYT-FC. The above findings, comparing the two extenders for preparation of frozen feline semen, showed that EYT-FC is slightly superior to EYC. To increase conception and fertility rates, it may be important to increase the sperm count for insemination and to inseminate both uterine horns.  相似文献