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111.
To date, little is known about the prognostic significance of ultrasonographic findings in dogs with protein-losing enteropathy (PLE). The aim of this retrospective study was to examine the prognostic value of ultrasonographic findings in dogs with PLE. A total of 26 dogs with PLE were included: 20 dogs with chronic enteropathy and 6 dogs with gastrointestinal lymphoma. The presence of small intestinal dilatation was associated with shorter survival time in dogs with PLE (P=0.003). The presence of hyperechoic intestinal mucosal striations was associated with longer survival time in dogs with PLE (P=0.0085). The results of the current study indicate that the presence of small intestinal dilatation might be associated with poor prognosis in dogs with PLE.  相似文献   
112.
A 15-day-old Holstein calf with lethargy and tachypnea presented to the Veterinary Teaching Hospital at Obihiro University of Agriculture and Veterinary Medicine for evaluation of suspected congenital heart defect. A Levine grade 6 systolic murmur was noted at right apical site auscultation and phonocardiogram also recorded systolic a murmur. Electrocardiography findings include increased R and S waves, R wave split, and negative T waves without arrhythmia. Echocardiography revealed a single ventricle with a trace of the right ventricular wall, atrioventricular valve regurgitation, and turbulent in a single ventricle. Arterial blood analysis showed a marked decrease in oxygen saturation of 78% and oxygen partial pressure of 44 mmHg. Post-mortem examination confirmed the diagnosis of a single left ventricle.  相似文献   
113.
We evaluated the effects of feeding high volumes of milk replacer on growth and reproductive performances in Japanese black heifers. Fifty-one heifers were fed milk replacer at 9 L/day for 60 days (9 L × 60 days; n = 18) or 41 days (9 L × 41 days; n = 15), or at 7 L/day for 40 days (7 L × 40 days; n = 18). Artificial insemination (AI) was performed on heifers with ≥270 kg body weight and ≥116 cm body height at 300 days of age. The age at the first AI was 0.35 month later for 7 L × 40 days than the other groups (p < .01). However, age at calving did not differ among treatments (22.1 months). The interval from the first AI to pregnancy tended to be ~2 months longer for the 9 L × 60 days than the other groups (p = .07). Our results showed that feeding high volumes of milk replacer may reduce the age at calving via an improved rate of growth. In addition, we propose that feeding a maximum of 7 L milk replacer for 40 days may be the most appropriate rearing regime because the success of pregnancy per AI may be reduced in calves fed a maximum of 9 L for 41 and 60 days.  相似文献   
114.
Birth weight and gestation length of calves following the transfer of in vitro produced (IVP) embryos with or without co-culture of cumulus cells, were compared to those produced in vivo (IVD). Spermatozoa from one Japanese Black bull were used for both IVP and IVD. IVP embryos were produced using two types of culture method: 1) co-culturing with cumulus cells in TCM 199 supplemented with calf serum (IVP-Co), and 2) non-co-culturing without cumulus cells in CR1aa supplemented with BSA / calf serum (IVP-NON-Co). Both IVP and IVD embryos were transferred non-surgically to Holstein recipients on day 7+/-1 of the estrous cycle. Birth weight and gestation length of half-sib single calves were analyzed. No differences were observed in birth weight and gestation length between IVP-Co and IVP-NON-Co calves (31.0 kg and 31.8 kg, and 291.9 days and 291.0 days, respectively). However, the birth weight of the IVP-Co and IVP-NON-Co calves was significantly higher than that of the IVD calves (P<0.01). Gestation length of the IVP-Co and IVP-NON-Co calves was also significantly longer than that of the IVD calves (P<0.01).  相似文献   
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Background

The feline endogenous retrovirus RD114 is contained in the genome of cats. The virus may contaminate live canine vaccines based on cultured feline cells. The in vivo infectivity, acute and subacute pathogenicity, and viral proliferation of the RD114 virus were evaluated by experimental infection of dogs.

Methods

Nine specific pathogen free dogs were divided into three groups, with each group consisting of one female and two male dogs. Dogs were subcutaneously inoculated in the neck with either 1 ml RD114 stock virus (group A), inactivated RD114 virus suspension (group B), or cell culture medium (group C) as a negative control. To assess blood cell counts and biochemical properties, blood samples from each group were collected 5 days before inoculation, just prior to inoculation, and 1, 3, 7 and 10 days post-inoculation.

Result

During the experimental period of 51 days, none of the dogs inoculated with RD114 virus showed any clinical signs, significant increases in rectal temperature or abnormal blood biochemical characteristics including C-reactive protein when compared with the negative controls. We were not able to re-isolate the RD114 virus from buffy coat cells of group A dogs. Additionally, we could not detect RD114 provirus in the genomic DNA isolated from peripheral blood leukocytes, lymph node, spleen and sternal bone marrow cells.

Conclusions

Signs of RD114 virus proliferation were not found after subcutaneous infection of dogs. Although the potential risk caused by infection with RD114 virus in dogs could not be assessed in this study, we suspect that RD114 virus has little or no virulence in dogs.  相似文献   
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Plant requires nitrogen for the growth, and it use nitrate and ammonium from the environment. Plant suffers from the toxicity when excess ammonium is supplied as a sole nitrogen, although it could be a good nitrogen source for plant growth. We hypothesized that the different responses of ecotypes to ammonium nutrient could partly account for the adaptation of Arabidopsis to an ammonium environment. The purpose of this study is to understand the different responses of ecotypes in ammonium environment. The growth of Arabidopsis thaliana ecotypes, Columbia was compared to those of Arabidopsis thaliana ecotypes, Landsberg erecta in ammonium nutrient. The ratio of shoot dry weight to root dry weight was compared to evaluate the adaptation of two ecotypes. The shoot:root ratio of Landsberg was significantly higher than that of Columbia. T-DNA insertion in cytosolic glutamine synthetase 1;2, one of the essential ammonium assimilatory enzymes, led a decrease of shoot:root ratio. We also measured the isotope-labeled ammonium uptake and the expression levels of ammonium transporter genes, and also the expression of ammonium assimilatory genes, glutamine synthetase genes and glutamate synthase genes, in roots after ammonium re-supply using real-time polymerase chain reaction analysis. We found that (1) ammonium uptake of Landsberg erecta was higher than that of Columbia, when ammonium was supplied at higher concentration, and (2) cytosolic glutamine synthetase 1;2 was highly increased by ammonium supply in the root of Landsberg erecta. The present study suggested the importance of these two factors for adaptation of Arabidopsis to an ammonium-rich environment.  相似文献   
119.
120.
ABSTRACT:   Annual changes in the gonadosomatic index (GSI), oocyte diameter, gonadal histology and plasma estradiol-17β (E2) levels were investigated in female common Japanese conger Conger myriaster in captivity. Juveniles were caught in September 1999 and reared in seawater at temperatures ranging from 10–20°C for 3 years. All fish were immature when captured in September 1999. GSI and oocyte diameter increased from October 2000, peaked between summer and autumn 2001, and bottomed-out in winter 2001. Plasma E2 level also increased from October 2000, but remained high. The ovarian developmental stage was at the peri-nucleolus stage or the oil droplet stage until September 2000. Vitellogenesis started in October 2000 and oocytes progressed to the tertiary yolk globule stage by summer 2001. However, vitellogenic oocytes regressed in all females after autumn 2001. The neogenetic oocytes began to increase after November 2001 and ovarian development progressed in 2002 as they did in 2001, although maximum GSI in 2002 was half its 2001 value. These data indicate that ovarian development in the common Japanese conger has an annual periodicity, and that these congers may be able to spawn in multiple years under rearing condition.  相似文献   
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