著者

Toshihiko TSUTSUI Tatsuya HORI Hisako OKAZAKI Ayuko TANAKA Masataka SHIONO Makoto YOKOSUKA Eiichi KAWAKAMI

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.63, no.4, pp.401-405, 2001 (Released:2001-05-10)

参考文献数

7

被引用文献数

25 29

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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.

著者

Tatsuya HORI Hitoshi USHIJIMA Taku KIMURA Masanori KOBAYASHI Eiichi KAWAKAMI Toshihiko TSUTSUI

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.16-0037, (Released:2016-04-03)

被引用文献数

5

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Canine embryos (8-cell to blastocyst stages) frozen–thawed using the slow-freezing method with glycerol (four recipients) or dimethyl sulfoxide (three recipients) as a cryoprotectant and vitrified–warmed using the Cryotop method (five recipients) were surgically transferred into the unilateral uterine horn of recipient bitches. As a result, the morphology of embryos frozen–thawed using the slow-freezing method was judged to be normal, but no conception occurred in any of the recipient bitches. Two of the five bitches that received transferred embryos (morula to early blastocyst stages) vitrified–warmed using the Cryotop method became pregnant and produced normal pups (1/9 embryos, 11.1% and 1/6 embryos, 17.0%). It was concluded that the Cryotop method was more appropriate for canine embryo cryopreservation than the slow-freezing method, which is used for the cryopreservation of embryos of other mammalian species.

著者

Eiichi KAWAKAMI Tatsuya HORI Toshihiko TSUTSUI

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.61, no.10, pp.1107-1111, 1999-10-25 (Released:2000-04-12)

参考文献数

33

被引用文献数

12 14

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The effects of a cryptorchid testis on the contralateral testis were investigated after artificially producing unilateral cryptorchidism in 8 beagle dogs. Bilateral testicular biopsy and collection of spermatic vein blood and peripheral vein blood were performed at the time of the operation to produce the cryptorchidism and 52 weeks later. The testicular tissue was used for histological examination by light microscopy and measurement of the testicular transferrin (Tf) concentration by enzyme immunoassay. Plasma testosterone (T), estradiol-17β (E2), and luteinizing hormone (LH) levels were measured by radioimmunoassay. Semen was collected weekly and its quality was examined. No spermatogenesis was observed in the cryptorchid testes at 52 weeks after the operation, and the number of germ cells in the contralateral testes had decreased but the number of Sertoli cells did not change. The Tf concentration in both testes had also decreased. The mean total number of sperm between 48 and 52 weeks after the operation (194 × 106) was less than half the number before the operation (510 × 106). Mean spermatic vein plasma T levels (51 ng/ml) in the cryptorchid testes 52 weeks after the cryptorchid operation were significantly lower than before the operation (91 ng/ml; P<0.05). By contrast, spermatic vein plasma E2 levels (80 pg/ml) were significantly higher than the values before the operation (51 pg/ml P<0.05). The peripheral plasma LH levels decreased. These findings indicate that a large quantity of E2 secreted by the cryptorchid testis inhibits the endocrine and spermatogenic functions of the contralateral testis in the dog. In particular, it is assumed that dysfunction of the contralateral testis is associated with Sertoli cell dysfunction suggested by the low Tf concentration.

著者

Moeko KOHYAMA Naomi TADA Hiroko MITSUI Hitomi TOMIOKA Toshihiko TSUTSUI Akira YABUKI Mohammad Mahbubur RAHMAN Kazuya KUSHIDA Keijiro MIZUKAMI Osamu YAMATO

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.15-0279, (Released:2015-11-06)

被引用文献数

1 11

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Canine progressive rod-cone degeneration (PRCD) is a middle- to late-onset, autosomal recessive, inherited retinal disorder caused by a substitution (c.5G>A) in the canine PRCD gene that has been identified in 29 or more purebred dogs. In the present study, a TaqMan probe-based real-time PCR assay was developed and evaluated for rapid genotyping and large-scale screening of the mutation. Furthermore, a genotyping survey was carried out in a population of the three most popular breeds in Japan (Toy Poodles, Chihuahuas and Miniature Dachshunds) to determine the current mutant allele frequency. The assay separated all the genotypes of canine PRCD rapidly, indicating its suitability for large-scale surveys. The results of the survey showed that the mutant allele frequency in Toy Poodles was high enough (approximately 0.09) to allow the establishment of measures for the prevention and control of this disorder in breeding kennels. The mutant allele was detected in Chihuahuas for the first time, but the frequency was lower (approximately 0.02) than that in Toy Poodles. The mutant allele was not detected in Miniature Dachshunds. This assay will allow the selective breeding of dogs from the two most popular breeds (Toy Poodle and Chihuahua) in Japan and effective prevention or control of the disorder.

著者

Mari TOYONAGA Toshihiko TSUTSUI

出版者

公益社団法人 日本獣医学会

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.74, no.10, pp.1349-1353, 2012 (Released:2012-11-02)

参考文献数

16

被引用文献数

2 7

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It is thought that differences in conception rate between feline epididymal sperm and ejaculate sperm occur because, unlike ejaculated sperm, caudal epididymal sperm have not been sensitized with seminal plasma (SP). In this study, we investigated whether collection of feline epididymal sperm with SP influences sperm qualities after freezing-thawing. Sperm were sensitized with SP for 10 min at room temperature. As a result, the motility of caudal epididymal sperm sensitized with SP immediately after collection was significantly lower than that of ejaculate sperm, and no difference was noted in sperm qualities after freezing-thawing. This shows that the qualities of caudal epididymal sperm cannot be improved to a level higher than those of ejaculate sperm by sensitization with SP.