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51.
The embryonic collection techniques in dogs present a vast methodological variation and low recovery rates. The objectives were to compare and describe two techniques as to the recovery of canine embryos, on the 12th day after the first mating or artificial insemination. Embryos were recovered through uterine horn flushing in vivo, before performing the ovariohysterectomy (OHE) (Group 1; n = 9) or ex vivo, immediately after the OHE (Group 2; n = 9). In total, 43 and 47 embryonic structures were recovered in Groups 1 and 2, respectively. There was no significant difference (p > 0.05) between groups on recovery rates (72.8% and 81.0%, respectively). We inferred that both in vivo and ex vivo techniques allow a high rate of embryonic recovery; in the collection technique prior to the OHE, it is essential to carefully handle the reproductive system during the trans‐surgical period and that the 12th day (D12) after the first mating/artificial insemination is an efficient option for the high recovery rate of morulae and blastocysts.  相似文献   
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Objective To perform in vivo analysis of retinal functional and structural parameters in healthy mouse eyes. Animal Studied Adult C57BL/6 male mice (n?=?37). Procedures Retinal function was evaluated using pattern electroretinography (pERG) and the chromatic pupil light reflex (cPLR). Structural properties of the retina and nerve fiber layer (NFL) were evaluated using spectral-domain optical coherence tomography (SD-OCT). Results The average pERG amplitudes were found to be 11.2?±?0.7?μV (P50-N95, mean?±?SEM), with an implicit time for P50-N95 interval of 90.4?±?5.4?ms. Total retinal thickness was 229.5?±?1.7?μm (mean?±?SEM) in the area centralis region. The thickness of the retinal nerve fiber layer (mean?±?SEM) using a circular peripapillary retinal scan centered on the optic nerve was 46.7?±?0.9?μm (temporal), 46.1?±?0.9?μm (superior), 45.8?±?0.9?μm (nasal), and 48.4?±?1?μm (inferior). The baseline pupil diameter was 2.1?±?0.05?mm in darkness, and 1.1?±?0.05 and 0.56?±?0.03?mm after stimulation with red (630?nm, luminance 200?kcd/m(2) ) or blue (480?nm, luminance 200?kcd/m(2) ) light illumination, respectively. Conclusions Pattern electroretinography, cPLR and SD-OCT analysis are reproducible techniques, which can provide important information about retinal and optic nerve function and structure in mice.  相似文献   
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Congenital portosystemic shunts in Maltese and Australian Cattle Dogs   总被引:2,自引:0,他引:2  
SUMMARY Congenital portosystemic shunts were definitively diagnosed in 62 dogs over a period of 15 years. Maltese and Australian Cattle Dogs were significantly over-represented, accounting for 14 and 13 cases, respectively. Maltese invariably had a single extrahepatic shunt derived from the left gastric or gastrosplenic vein, whereas Cattle Dogs usually had large intrahepatic shunts involving the right liver lobes. The clinical syndromes resulting from anomalous portosystemic communications were indistinguishable in the 2 breeds. Fasting blood ammonia concentration was elevated in 20 of 22 dogs tested, providing a minimally invasive and effective means of diagnosis. Complete or partial shunt attenuation was performed successfully in all 9 Maltese and in 2 of 6 Cattle Dogs in which it was attempted.  相似文献   
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The effects of the botanical insecticides Biopiren plus, Piresan plus and Neemazal T/S on the predatory mite Amblyseius andersoni (Chant) were tested under laboratory, semi-field, and field conditions. The tests carried out in the laboratory allowed detection of the direct toxicity on eggs and females as well as the effects on fecundity, whereas semi-field trials assessed their residual toxicity. In laboratory and semi-field tests, pyrethrins, particularly Piresan plus, proved to have the highest toxicity with E value, concerning both female mortality and fecundity, of 100% and 45%, respectively. The same product tested in the field only caused a significant reduction in the phytoseiid population shortly after the treatment. The relevant escape rate registered in semi-field tests could explain the lack of phytoseiid eradication in the field after treatment with pyrethrins.  相似文献   
57.
The effects of the botanical insecticides Biopiren plus, Piresan plus and Neemazal T/S on the predatory mite Amblyseius andersoni (Chant) were tested under laboratory, semi-field, and field conditions. The tests carried out in the laboratory allowed detection of the direct toxicity on eggs and females as well as the effects on fecundity, whereas semi-field trials assessed their residual toxicity. In laboratory and semi-field tests, pyrethrins, particularly Piresan plus, proved to have the highest toxicity with E value, concerning both female mortality and fecundity, of 100% and 45%, respectively. The same product tested in the field only caused a significant reduction in the phytoseiid population shortly after the treatment. The relevant escape rate registered in semi-field tests could explain the lack of phytoseiid eradication in the field after treatment with pyrethrins.  相似文献   
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响应面法优化姬松茸液体发酵培养基中红糖和酵母膏浓度   总被引:6,自引:0,他引:6  
运用响应面分析法优化姬松茸液体发酵培养基中红糖和酵母膏浓度.结果表明,红糖浓度为20.24g/L、酵母膏浓度为2.055g/L时,菌丝体生物量最高,达2.279g/L;红糖浓度为20.8g/L、酵母膏浓度为2.23g/L时,胞外多糖产量最高,达0.749g/L.  相似文献   
59.
A free-living mouflon (Ovis musimon) was presented with a mass on the left shoulder. At necropsy, multifocal, slightly protruding whitish spots were noted on the kidneys, and several lymph nodes were abnormal. Histologically, the mass was composed of epithelial cells arranged in tubular and tubulopapillary structures. The cytoplasm of the epithelial cells had numerous periodic acid-Schiff-positive and diastase-resistant granules. Ultrastructurally, the cytoplasm of the neoplastic cells contained numerous pleomorphic secretory granules and microvilli, which partially covered the luminal surface of the tumor cells. Metastatic foci were present in prescapular and mediastinal lymph nodes and kidneys. On the basis of histological and ultrastructural findings, this tumor was diagnosed as a tubulopapillary adenocarcinoma, arising from apocrine sweat glands of the skin.  相似文献   
60.
Lactobacillus rhamnosus as additive for maize and sorghum ensiling   总被引:2,自引:0,他引:2  
The effects of Lactobacillus rhamnosus AT195, a potential probiotic microorganism cultured in buffalo "scotta" whey, on chemical and microbiological composition in maize and sorghum ensiling were evaluated. Both crops were harvested, chopped, and treated or not with the selected strain prior to ensiling in fiberglass vertical silos; 90 days after ensiling, silages were sensorially evaluated and sampled. Different chemical components were evaluated both on fresh crops and silages: in particular, the water-soluble carbohydrates content was investigated by high-field NMR spectroscopy and the carbohydrate fermentation profile was performed by GC. Besides phenotypic identification and typing, microbiological studies included Lb. rhamnosus genotype typing by RAPD-PCR. All silages, inoculated or not, were well preserved, as their chemical and microbiological data along with the fermentation profiles showed. The selected strain used as inoculum influenced the lactic acid population of silages and evidenced a good survival performance during the ensiling process of both maize and sorghum. Moreover, the use of Lb. rhamnosus strain efficiently improved the quality of the multifactorial ensiling process by significantly reducing the ammonia nitrogen content of both maize and sorghum silages.  相似文献   
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