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Kumiko TAKEDA Masahiro SATOH Shreeram P. NEOPANE Bahadur S. KUWAR Hari D. JOSHI Nanda P. SHRESTHA Hiroshi FUJISE Mariko TASAI Takahiro TAGAMI Hirofumi HANADA 《Animal Science Journal》2004,75(2):103-110
Dwarf Lulu cattle, the only Bos Taurus type of cattle in Nepal, are raised under severe environments in the mountainous zone of that country. In the present study, the body measurement traits, cytogenetic and molecular genetic characteristics of the Lulu cattle are investigated. Blood samples were collected from 31 animals in four villages (altitudes 2590–3550 m) in the southern part of Mustang. The Lulu cattle had a normal karyotype with 2n = 60, XY or XX. Only one male examined had a large submetacentric X‐chromosome and a small submetacentric taurine type Y‐chromosome. The mitochodrial DNA (mtDNA) genotypes were analyzed by PCR mediated restriction fragment length polymorphisms, displacement (D)‐loop region PCR mediated single strand conformation polymorphisms, and D‐loop region sequences. Many base substitutions were found in the D‐loop region, suggesting that the Lulu cattle originated from at least 10 maternal lines. Three types of mtDNA from these cattle were found, the Bos taurus type (n = 23), the Bos indicus type (n = 6), and the Bos grunniens type (n = 2). In the village at the lowest altitude, four of the five cows were of the Bos indicus type. These results indicated that mtDNA types of the Lulu cattle mostly belong to Bos taurus, but have been hybridized with Bos indicus cattle in lower‐elevation regions in their maternal lineage. 相似文献
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Milagros Virhuez MENDOZA Kenzo YONEMITSU Keita ISHIJIMA Yudai KURODA Kango TATEMOTO Yusuke INOUE Hiroshi SHIMODA Ryusei KUWATA Ai TAKANO Kazuo SUZUKI Ken MAEDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(7):992
In Japan, hepatitis E virus (HEV) causes hepatitis in humans through the consumption of raw or undercooked meat, including game meat. In the present study, nationwide surveillance of HEV infection among a total of 5,557 wild animals, including 15 species, was conducted in Japan. The prevalence of anti-HEV antibodies in wild boar was 12.4%, with higher positive rates in big boars (over 50 kg, 18.4%) than in small individuals (less than 30 kg, 5.3%). Furthermore, HEV RNA was more frequently detected in piglets than in older boars. Interestingly, the detection of HEV among wildlife by ELISA and RT-PCR suggested that HEV infection in Sika deer was a very rare event, and that there was no HEV infection among wild animals except for wild boar, Sika deer and Japanese monkeys. In conclusion, wild boar, especially piglets, are at high risk of HEV infection, while other wild animals showed less risk or no risk of HEV transmission. 相似文献
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Munekazu Nakaichi Toshie Iseri Hiro Horikirizono Harumichi Itoh Hiroshi Sunahara Yuki Nemoto Kazuhito Itamoto Kenji Tani 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(6):633
The pedigrees of 3 Dalmatian dogs afflicted with copper-associated hepatitis were investigated to discover the mode of inheritance. A composite family pedigree showed that the 3 affected Dalmatians were related. None of the parents of the affected dogs showed clinical symptoms of liver disease, and the disease had no sex predisposition. The estimated segregation ratio was approximately 3:1 based on surviving littermates. These findings suggested that the copper-associated hepatitis in these Dalmatians was an autosomal recessive mode of inheritance. In addition, some male Dalmatians imported from abroad might have been involved in the occurrence of this disease in Japan. 相似文献
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DURITAHALA Mitsuhiro SAKASE Hiroshi HARAYAMA 《The Journal of reproduction and development》2022,68(3):181
In cattle, cryopreserved spermatozoa are generally used for artificial insemination (AI). Many of these specimens exhibit helical movement, although the molecular mechanisms underlying this phenomenon remain unclear. This study aimed to characterize helically motile spermatozoa, investigate the involvement of Ca2+-ATPase in suppressing the appearance of these spermatozoa prior to cryopreservation, and examine the potential of helical movement as an index of sperm quality. In the cryopreserved semen, approximately 50% of spermatozoa were helically motile, whereas approximately 25% were planarly motile. The helically motile samples swam significantly faster than those with planar movement, in both non-viscous medium and viscous medium containing polyvinylpyrrolidone. In contrast, in non-cryopreserved semen, planarly motile spermatozoa outnumbered those that were helically motile. Fluorescence microscopy with Fluo-3/AM and propidium iodide showed that flagellar [Ca2+]i was significantly higher in cryopreserved live spermatozoa than in non-cryopreserved live ones. The percentage of non-cryopreserved helically motile spermatozoa was approximately 25% after washing, and this increased significantly to approximately 50% after treatment with an inhibitor of sarcoplasmic reticulum Ca2+-ATPases (SERCAs), “thapsigargin.” Immunostaining showed the presence of SERCAs in sperm necks. Additionally, the percentages of cryopreserved helically motile spermatozoa showed large inter-bull differences and a significantly positive correlation with post-AI conception rates, indicating that helical movement has the potential to serve as a predictor of the fertilizing ability of these spermatozoa. These results suggest that SERCAs in the neck suppress the cytoplasmic Ca2+-dependent appearance of helically motile spermatozoa with intense force in semen prior to cryopreservation. 相似文献
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Yoshimasa SASAKI Taketoshi IWATA Masashi UEMA Kenzo YONEMITSU Shizunobu IGIMI Hiroshi ASAKURA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):743
Chicken is a major source of human campylobacteriosis. Chicken meat originates not only from broilers but also from spent layers; however, few reports have documented the prevalence and antimicrobial resistance of Campylobacter spp. in layers in Japan. Therefore, we investigated the prevalence and antimicrobial susceptibility of Campylobacter spp. in 47 layer farms in Japan. Fecal samples were collected from the youngest and oldest flocks on the farm, and Campylobacter spp. was isolated from 46/47 (97.9%) farms. Among the C. jejuni isolates, the resistance rates to ampicillin, tetracycline, and ciprofloxacin were 29.6%, 22.2%, and 19.8%, respectively. The ciprofloxacin resistance rate (7.3%) in C. jejuni isolated from old flocks was significantly (P<0.01) lower than that in young flocks (32.5%). 相似文献
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Naomi JACK Tomoyuki MUTO Keigo IEMITSU Tamaki WATANABE Kazuhiro UMEYAMA Jun OHGANE Hiroshi NAGASHIMA 《The Journal of reproduction and development》2022,68(4):233
Recent developments in reproductive biology have enabled the generation of genetically engineered pigs as models for inherited human diseases. Although a variety of such models for monogenic diseases are currently available, reproduction of human diseases caused by haploinsufficiency remains a major challenge. The present study compares the phenotypes of mouse and pig models of Marfan syndrome (MFS), with a special focus on the expressivity and penetrance of associated symptoms. Furthermore, investigation of the gene regulation mechanisms associated with haploinsufficiency will be of immense utility in developing faithful MFS pig models. 相似文献
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【目的】戊型肝炎病毒(Hepatitis Evirus,HEV)感染是一种人畜共患病,而猪是HEV的病毒储库。在日本,HEV感染已成为猪的地方性猪病。阐明HEV在猪场中的详细传播机制,将有利于人们掌握特定年龄段猪群的感染状况,尤其是肉猪在屠宰前的感染状况。【结果】本文,作者重新分析了源于日本猪场的一个大型猪HEV血清阳性率数据集,以此评估HEV的感染力。结果表明,北海道、本州和九州三个地区猪场中的猪HEV感染力分别为3.45×10-2/d(95%的置信区间(下同):3.17~3.75×10-2/d)、2.68×10-2/d(2.28~3.14×10-2/d)和3.11×10-2/d(2.76~3.50×10-2/d)。利用作者建立的模型得到的估测结果表明,猪感染HEV的平均日龄在59.0~67.3d之间,其基本传染数R0按4.02~5.17的数量级递增。对特定年龄猪群在不同感染力下的敏感性分析显示,HEV感染力下降将提高猪感染HEV的年龄,而且会增加180日龄时散毒猪的数量。【结论】尽管作者的研究表明95%以上的猪是在150日龄前被感染的,但该模型显示感染力下降可以增加感染猪将HEV传播给人的风险。如果感染力开始下降,就有必要采取基本的应对策略(如在哺乳期末将未感染猪与感染猪分开)以最大限度地减少肥育阶段的HEV阳性猪数量。 相似文献