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排序方式: 共有312条查询结果,搜索用时 12 毫秒
41.
Katsuji UETAKE Toshie ISHIWATA Naoshige ABE Yusuke EGUCHI Toshio TANAKA 《Animal Science Journal》2005,76(6):581-586
The differential variables for carcass grades were identified from morphological, behavioral and physiological measurements of young steers at a commercial farm. Thirty‐five Japanese Black × Holstein steers aged 6–10 months were randomly assigned to three pens. The steers had free access to ryegrass hay and a restricted amount of concentrate diet for the first 6 months of trial. They were then given oat straw ad libitum and an additional concentrate diet until slaughter. Behavioral observations (15 categories) were carried out once every 2 weeks for 2 h after feeding. Bodyweight was measured, blood sampled (for seven metabolic hormones and five metabolites), ultrasonic scanning conducted and physical measurements taken (10 parts for each animal) in months 1, 3 and 5 (early fattening stage, EFS) and in months 7, 9 and 11 (middle fattening stage, MFS) of the trial. Temperament scores during these procedures, entry order into restraint stalls, social rank and average daily gain were also assessed. A factor analysis and one‐way anova were used to identify clusters of variables which had different factor scores between carcass grades. As for the carcass yields, a cluster of chest girth and depth, bodyweight, withers and hip height, and rump length (P < 0.01), and a cluster of the frequency of scratching the body with facilities (P < 0.05) were identified as differential variables in the EFS. In the MFS, a cluster of concentrations of cortisol and epinephrine, and the frequency of eating straw were identified (P < 0.10). As for the carcass quality grade, a cluster of social rank, triglyceride concentration and the frequencies of stand‐chewing cud and eating hay, and a cluster of the frequency of investigating facilities (both P < 0.10) were identified in the EFS. In the MFS, a cluster of hip height, bodyweight, cannon circumference, chest depth, withers height and chest girth, and a cluster of the frequencies of eating a concentrate diet and stand‐chewing the cud, and social rank (both P < 0.10) were identified. In conclusion, bodyweight, chest girth and depth, withers and hip height were identified as good differential variables for future carcass grades of young steers. Facility enrichment that encourages steers to eat hay in the EFS, and to eat a concentrate diet in and after the MFS would be effective in upgrading carcass grades. High incidence of investigating and scratching the body with facilities and stand‐chewing the cud might lead to lower carcass grades. 相似文献
42.
Takeuchi Y Matsuura S Fujino Y Nakajima M Takahashi M Nakashima K Sakai Y Uetsuka K Ohno K Nakayama H Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(10):1085-1089
Two cats showing chronic vomiting, diarrhea and weight loss were found to have leukocytosis with marked eosinophilia. Both cats were diagnosed with hypereosinophilic syndrome by the findings of increased eosinophils and their precursors in the bone marrow, eosinophilic infiltration into multiple organs, and exclusion of other causes for eosinophilia. Although cytoreductive chemotherapy with hydroxycarbamide and prednisolone was performed, these two cats died 48 days and 91 days after the initial presentation. 相似文献
43.
Glomerular lipidosis is a disease characterized by lipid accumulation in mesangial cells but that has not been fully investigated in avian species. We examined four wild and two laboratory-reared Japanese rock ptarmigans (Lagopus mutus japonicus)--an endangered avian species--presenting vacuolar deposits in the glomeruli. All cases had vacuolar deposits in the glomeruli. In the wild cases, fewer than 30% of all glomeruli were affected, compared with more than 90% in the laboratory-reared cases. In the wild cases, most deposits were mild and restricted to the mesangial areas of glomeruli. In the laboratory-reared cases, nearly all of the deposits covered entire glomeruli. Electron microscopy of mild deposits revealed vacuoles in the cytoplasm of mesangial cells. These vacuoles were positive for Sudan III, Sudan black B, oil red O, Nile blue, periodic acid-Schiff, Schultz test, and digitonin stain and were negative for performaric acid-Schiff stains. Based on these results, we diagnosed the glomerular lesion as glomerular lipidosis caused by uptake of low-density lipoprotein in mesangial cells. Except for one wild case, all cases exhibited renal tubular oxalosis. The severity of tubular oxalosis tended to be related to the severity of glomerular lipidosis: In cases of mild glomerular lipidosis, tubular oxalosis was also mild or absent. We therefore diagnosed the primary lesion as glomerular lipidosis accompanied by tubular oxalosis. The four wild cases came from different zones and therefore had no opportunities to interbreed and no common relatives. We believe these data support the hypothesis that glomerular lipidosis is a disease of the general population ofJapanese rock ptarmigans. This is the first report of glomerular lipidosis accompanied by renal tubular oxalosis in an avian species. 相似文献
44.
Okabayashi K Kano R Sirouzu K Yanai T Mizuno M Yamamura H Saegusa S Hasegawa A 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(8):953-955
Two feline cases were diagnosed as systemic cryptococcosis due to Cryptococcus neoformans (teleomorph: Filobasidiella neoformans) by PCR assay with CAP59 gene primers using urine, serum and biopsy samples. The results of molecular analysis were consistent with the mycological findings. 相似文献
45.
Murase Y Konnai S Hidano A Githaka NW Ito T Takano A Kawabata H Ato M Tajima T Tajima M Onuma M Murata S Ohashi K 《Veterinary microbiology》2011,149(3-4):504-507
The tick-borne pathogen, Anaplasma phagocytophilum (A. phagocytophilum), the causative agent of human granulocytic anaplasmosis (HGA), is increasingly becoming a public health concern as an aetiological agent for emerging infectious disease. We found A. phagocytophilum infection in a pooled sample of field-collected Ixodes persulcatus (I. persulcatus) ticks from one district in Hokkaido, Japan. Thus, to further investigate the prevalence in field-collected ticks, we used PCR assays targeting the A. phagocytophilum gene encoding 44 kDa major outer membrane protein (p44) for screening of I. persulcatus ticks and samples from cattle from pastures. Out of the 281 I. persulcatus ticks, 20 (7.1%) were found to harbor A. phagocytophilum DNA. The infection rate for A. phagocytophilum in cattle was 3.4% (42/1251). In future studies, it will be necessary to investigate effects of the infection in order to understand its pathogenesis of A. phagocytophilum in domestic animals. 相似文献
46.
Hamada N Takahashi Y Watanabe K Kumada H Oishi Y Umemoto T 《Veterinary microbiology》2008,128(1-2):108-117
Porphyromonas gulae is black-pigmented anaerobic bacteria associated with canine periodontitis. There is little information available about the specific identify and relative occurrence of pigmented anaerobes in companion animals. Our aim was to clarify the factor involved in the adherence and colonization of the organism in the oral cavity. Fimbrial protein was purified from P. gulae ATCC 51700. The molecular mass of this protein was approximately 41kDa as estimated by SDS-PAGE. An antibody against 41-kDa fimbrial protein from P. gingivalis ATCC 33277 reacted with fimbrillin of P. gulae ATCC 51700. Immunogold electron microscopy revealed that the anti-41kDa fimbrial serum bound to fimbria on the cell surface of P. gulae ATCC 51700. Thus, fimbrial protein of P. gulae ATCC 51700 had the same size and antigenicity as 41-kDa fimbriae of P. gingivalis ATCC 33277. The nucleotide sequence of the fimA gene from P. gulae ATCC 51700 showed 94% homology with that of P. gingivalis ATCC 33277. Moreover, the deduced amino acid sequences have 96.8% identity. P. gulae has adherent ability to gingival epithelial cells. The properties of P. gulae fimbriae are similar to those of P. gingivalis fimbriae. We suggest that the surface structure of P. gulae may play a role in the colonization of this organism in periodontal pockets in companion animals. 相似文献
47.
Satoshi HARA Takashi TAKANO Mio OGATA Reina YAMAKAMI Yusuke SATO Tomohiro KONO Yayoi OBATA 《The Journal of reproduction and development》2014,60(3):250-255
Transgenic mice are essential research tools in developmental biology studies. The 2A peptide allows multiple genes to be
expressed simultaneously at comparable levels in somatic cells, but there are no reports of it being used successfully in
germ cells. We constructed a Cre/loxP-based conditional vector containing the 2A peptide to significantly enhance the
expression of a reporter and target gene from a constitutive promoter in oocytes. Mice with a transgene insertion containing
the chicken β-actin promoter, floxed EGFP-polyA cassette, mCherry reporter, 2A peptide and target gene DNA methyltransferase
3A2 (Dnmt3a2) were crossed with TNAP- or Vasa-Cre mice to produce offspring, in which mCherry and DNMT3A2
proteins were highly expressed in oocytes upon Cre-mediated removal of EGFP-polyA. This novel transgenic mouse line based on
the 2A expression system can serve as a useful tool for examining gene function during oogenesis. 相似文献
48.
Furuuchi R Yokoyama T Watanabe Y Hirayama M 《Journal of agricultural and food chemistry》2011,59(8):3738-3746
Proanthocyanidins and other polyphenols in the seeds and juice of boysenberry were quantitatively analyzed. Polyphenolic extracts were prepared from the waste seeds and commercial juice by chromatographic fractionation. Compositional analysis revealed that both extracts contained six polyphenolic classes: flavanol monomers, proanthocyanidins, anthocyanins, ellagic acid, ellagitannins, and flavonol glycosides. Ellagitannins were the most abundant polyphenols in both extracts. Proanthocyanidins were present as short oligomers consisting of dimeric and trimeric procyanidins and propelargonidins, with the most abundant component being procyanidin B4 in both extracts. Quantification by high-performance liquid chromatography-mass spectrometry (HPLC-MS) revealed that the seeds contained a 72-fold higher amount of proanthocyanidins than the juice. These results indicate that boysenberry fruits contain short oligomeric proanthocyanidins along with flavanol monomers and the seeds represent a good source of short oligomeric proanthocyanidins. 相似文献
49.
Mami Murakami Hiroki Sakai Nao Iwatani Aki Asakura Yuki Hoshino Takashi Mori Tokuma Yanai Kohji Maruo Toshiaki Masegi 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(1):113-118
Abstract: A 15‐month‐old castrated male dog with a history of intermittent epistaxis and sneezing was admitted for the examination of a maxillofacial mass. An impression smear of a biopsy sample from the cauliflower‐shaped gingival mass contained numerous round cells, 5–25 μm in diameter, which contained a moderate amount of clear to pale blue cytoplasm and resembled lymphoid cells. Mitotic figures were frequently observed. The mass was diagnosed as malignant round cell neoplasia. On histologic examination the tumor was composed of diffusely arranged, small, atypical round cells with a small amount of fibrovascular stroma. Immunohistochemically, the cells were negative for CD3, CD18, CD20, CD79α, cytokeratin, melan‐A, chromogranin A, α‐smooth muscle actin, and myoglobin but positive for vimentin and desmin. The cells also had strong positive nuclear staining for myogenin and MyoD1. A diagnosis of solid‐pattern alveolar rhabdomyosarcoma was made on the basis of morphologic and immunohistochemical results. Alveolar rhabdomyosarcoma should be considered in the differential diagnosis of tumors in juvenile dogs, especially when cytologic findings reveal round, undifferentiated cells. 相似文献
50.
Yoshiki HIRATA Yusuke KATSUKURA Yuka HENMI Ren OZAWA Sayaka SHIMAZAKI Akira KUROSAWA Yasushi TORII Hironori TAKAHASHI Hisataka IWATA Takehito KUWAYAMA Koumei SHIRASUNA 《The Journal of reproduction and development》2021,67(4):257
Advanced maternal age is a risk factor for female infertility, and placental dysfunction is considered one of the causes of pregnancy complications. We investigated the effects of advanced maternal aging on pregnancy outcomes and placental senescence. Female pregnant mice were separated into three groups: young (3 months old), middle (8–9 months old), and aged (11–13 months old). Although the body weights of young and middle dams gradually increased during pregnancy, the body weight of aged dams only increased slightly. The placental weight and resorption rate were significantly higher, and live fetal weights were reduced in a maternal age-dependent manner. Although mRNA expression of senescence regulatory factors (p16 and p21) increased in the spleen of aged dams, mRNA expression of p16 did not change and that of p21 was reduced in the placenta of aged dams. Using a cytokine array of proteins extracted from placental tissues, the expression of various types of senescence-associated secretory phenotype (SASP) factors was decreased in aged dams compared with young and middle dams. The aged maternal placenta showed reduced immune cell accumulation compared with the young placenta. Our present results suggest that models using pregnant mice older than 8 months are more suitable for verifying older human pregnancies. These findings suggest that general cellular senescence programs may not be included in the placenta and that placental functions, including SASP production and immune cell accumulation, gradually decrease in a maternal age-dependent manner, resulting in a higher rate of pregnancy complications. 相似文献