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111.
The barber goby, Elacatinus figaro, is a cleaner species of ecological importance and of keen interest to the aquarium trade. Endemic to Brazil, it is a threatened species and so aquaculture is a potential solution for reducing pressure on the natural stocks. This study describes the reproductive behaviour, the embryonic and larval development and the general breeding and rearing conditions. Ten wild fish initiated the formation of breeding pairs 20 days after acclimation to captivity. Spawning started 12 days after the first pair was formed, with one female from each pair spawning from 140 to 700 eggs (n=15 spawnings). The average period of incubation of the eggs was 6.8 days at 25 °C. The best hatching rate was 99.5% (n=10 spawnings). Larval rearing used Nannochloropsis oculata with rotifers (Brachionus rotundiformis) as the first food (day 0–25); nauplii and meta‐nauplii of Artemia were fed from day 18 until larval metamorphosis with subsequent weaning using commercial marine fish diets. The transformation to juveniles started at around the 30th day post hatch. The best larval survival rate until complete metamorphosis was 30.6% (n=4 larvicultures). After this period, the mortality was insignificant. This study demonstrated that the cultivation of barber goby is feasible.  相似文献   
112.
A rabbit (Oryctolagus cuniculus) with a homologous malignant mixed müllerian tumor (MMMT) of the uterus with decidualization in the sarcomatous components is described. On histologic examination, the neoplasm was characterized by a carcinomatous and a sarcomatous component with invasion of the myometrium. The epithelial component was a well-differentiated carcinoma, and the nonepithelial component contained large amounts of intracytoplasmic glycogen. The changes in stromal cells were morphologically similar to changes usually found in decidual cells in the pregnant uterus or in deciduosarcomas in rabbits. Results of immunohistochemical analysis indicated that the epithelial components stained positive with cytokeratin (CK7, AE1/3) and the decidual-stromal cells stained positive for vimentin, but did not stain with alpha-SMA, actin, and desmin. This case fulfills all the criteria of an MMMT in having a carcinomatous and a sarcomatous component, but differs from cases of MMMT in women in that the sarcomatous component had decidualized. To the authors' knowledge, this is the first report of a malignant mixed müllerian tumor in rabbits.  相似文献   
113.
The purpose of our publication is to widely communicate the pictures of spontaneous findings occurring in beagles. Spontaneous arteritis occurs commonly in beagles. Frequent sites of arteritis are the heart, spleen, pancreas, epididymis and spinal cord. Morphological similarities between spontaneous and drug-induced arterial lesions may cause confusion when evaluating vascular toxicity of chemicals such as vasodilating agents. Focal and minimal inflammatory lesions are occasionally seen in the lung and may be associated with aspiration of food particles or of unknown causes. A cystic change with copious mucin production occurs occasionally in the mucosal epithelium of the gall bladder. Nesidioblastosis is seen rarely in the pancreas of beagles. C-cell complex and lymphocytic thyroiditis are common thyroid lesions. Spontaneous focal hypospermatogenesis and lobular Sertoli-cell-only seminiferous tubules occurring frequently in beagles must be distinguished from drug-induced damage of the seminiferous tubules in toxicity studies. The morphological differences of the female genital system in each cycle need to be understood; therefore, we present the normal features of the cyclic changes of the female genital organs. Further, we provide more information on spontaneous findings in beagles for exact diagnoses in toxicity studies.  相似文献   
114.
An adult male Japanese giant salamander (Andrias japonicus) died accidentally, and necropsy showed a white mass (23 × 15 mm) in the left kidney and hepatorrhexis with hemoperitoneum. Histologically, the renal mass was mainly composed of immature nephroblastic tumor cells. In the tumor tissue, a trabecular pattern lined by oval to polygonal tumor cells with a rich interstitium, solid growth and a few tubular structures was observed. Nephroblastic tumor cells were strongly positive for vimentin and weakly positive, and epithelium-like tumor cells were strongly positive for cytokeratin. However, antibody for Wilms' tumor protein 1 did not react with the salamander's cells. On electron microscopy, a desmosome junction was observed between tumor cells. This is the first report of nephroblastoma in a Japanese giant salamander.  相似文献   
115.
In the spring of 2007, seven raccoon dogs and a weasel were captured near the city of Tanabe in Wakayama prefecture, Japan. The causative agent of the animals' death 1-2 days after capture was identified as canine distemper virus (CDV) by virus isolation, immunostaining with an anti-CDV polyclonal antibody, and a commercially available CDV antigen-detection kit. Sequence analysis of hemagglutinin genes indicated the isolated viruses belong to genotype Asia-1 and possess the substitution from tyrosine (Y) to histidine (H) at position 549 that is associated with the spread of CDV to non-canine hosts. A serosurvey for CDV was then conducted among wild animals in the region. The animals assayed consisted of 104 raccoons, 41 wild boars, 19 raccoon dogs, five Sika deer, two badgers, one weasel, one marten, one Siberian weasel and one fox. Virus-neutralization (VN) tests showed that, except for fox and weasel, all of the species assayed had VN antibodies to CDV. Interestingly, 11 of the 41 wild boars (27%) and two of the five Sika deer assayed possessed VN antibodies to CDV. These findings indicate that CDV infection was widespread among wild mammals during this epizootic.  相似文献   
116.
Insulin‐like growth factor‐1 (IGF1) plays an important role in muscle development in chickens. In this study, an F2 chicken population of 362 individuals, obtained from an intercross between high breast muscle yield line males and low breast muscle yield (LB) line females, was constructed for investigating the associations between IGF1 gene and breast muscle yields. The IGF1 sequence was investigated in the grandparents. There were no differences in the exon sequences. However, sequence analysis of the IGF1 promoter revealed a known single nucleotide polymorphism (g.570C > A) in LB line grandparents. PCR – restriction fragment length polymorphism was used for screening the F2 population, which was evaluated for body weight (BW), carcass weight (CW), breast muscle weight (BMW), and breast fillet weight (BFW). Significant associations with the polymorphism were detected for BMW, BFW, BMW% and BFW%, although there were no associations between the polymorphism and BW or CW. The allelic effect on BMW, BFW, BMW% and BFW% acted in additive and dominance modes. We confirmed that the g.570C > A polymorphism is significantly associated with breast muscle yields in the F2 population. Therefore, this polymorphism in the IGF1 gene may help improve breast muscle yields by marker‐assisted selection.  相似文献   
117.
Post-import from the Republic of Indonesia to Japan in 2017, two juvenile, captive bred Asian small-clawed otters (Aonyx cinereus) exhibited gastrointestinal symptoms, including vomiting, diarrhea, and hematemesis, and died. One of them was examined postmortem. Microscopically, the small intestinal mucosa was necrotic with crypts lined by regenerating large epithelial cells. A gastric cardiac mucosal ulcerative lesion containing fungal yeasts and pseudohyphae morphologically indicated Candida spp. The lymph nodes exhibited marked lymphoid depletion. Canine parvovirus 2 (CPV-2) was isolated from an oral swab, and virus protein 2 (VP2) gene sequencing revealed new CPV-2a. To our knowledge, this is the first new CPV-2a infection report in Asian small-clawed otters. This infection should be considered in gastrointestinal symptom-related cases in this species.  相似文献   
118.
This study reports findings from the pathological examination of the forestomach of an 11-month-old Japanese Black steer with severely retarded growth (41% of expected weight) and chronic ruminal tympany. The ruminal papillae were weakly formed (0.3–0.5 cm long) and unevenly distributed. The cellulae and cristae reticuli were underdeveloped; the cristae were 0.4–0.7 cm in height and milky white. The keratinized layer in the stratified squamous epithelium was thickened. Ruminal pH was 5.25, and ruminal volatile fatty acid concentration was 11.7 mM. The steer’s severely retarded growth was considered to be caused by malnutrition due to developmental and functional failure of the forestomach.  相似文献   
119.
120.
Despite high expectations of nongovernmental organizations (NGOs) as project partners in bilateral-aid community forestry (CF) projects in Nepal, it remains unclear whether the NGO involvement favored by donors is efficient. This study examined the influence of NGOs on local people's perceptions of CF management by using a quantitative analysis based on a questionnaire survey. Three different forest user groups (FUGs) supported by the Nepal Swiss Community Forestry Project were selected from the Dolakha and Ramecchap districts: an FUG supported by another FUG acting as an NGO, an FUG supported by an NGO specializing in CF, and an FUG without NGO support. A structured survey examined the perception of CF management based on satisfaction, involvement, and self-reliance in 244 selected households belonging to the three FUGs. Knowledge of CF and personal information was also surveyed and analyzed. The results showed that NGO involvement influences factors such as self-reliance and knowledge of CF. FUG members who were supported by an NGO or an FUG had a significantly higher perception with respect to self-reliance and knowledge than did members without such support. This indicates that experienced FUGs can serve as adequate service providers for the CF formation procedure, in a manner similar to that of NGOs. On the other hand, the limited support from NGOs or FUGs during the formation process seemed insufficient to fulfill the expectations of aid agencies with respect to the enhancement of satisfaction and active participation on the part of FUG members. If aid agencies expect NGOs and FUGs to enhance the satisfaction and participation of members, these intermediary organizations should be assigned to support more CF activities than just the formation procedure. Aid agencies should take responsibility for strengthening the capabilities of NGOs and FUGs, as needed.  相似文献   
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