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排序方式: 共有577条查询结果,搜索用时 31 毫秒
571.
Luiza Stachewski Zakia Mariana Isa Pocci Palumbo Raffaella Bertoni Cavalcanti Teixeira Luiz Antnio Lima Resende Mauro Pereira Soares Jos Paes de Oliveira‐Filho Rogrio Martins Amorim Alexandre Secorun Borges 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):287-291
This article describes the clinical and electromyographic findings of neuromyotonia in a 19‐month‐old male crossbred Quarter Horse that presented with stiffness and muscle asymmetry in the hind limbs as well as sacrococcygeal, paravertebral, and gluteal myokymia. An electromyographic study showed spontaneous continuous muscle fiber activity with high‐frequency discharges, fibrillations, positive sharp waves, fasciculation potentials, and complex repetitive discharges. Histological examination of the gluteal muscle showed a mixed neurogenic and myopathic pattern. The findings are consistent with neuromyotonia. 相似文献
572.
A new form of toxicity called equine fescue oedema is described. The clinical signs included inappetence, depression, and subcutaneous oedema of the head, neck, chest and abdomen. Affected horses had very low plasma albumin values. The toxicity affected 48 of 56 horses on six farms in different states of Australia, and 4 horses have died. All horses were grazing pastures that had been sown with varieties of Mediterranean tall fescue (Festuca arundinacea) that carry the endophyte known as Max P or Max Q. It is proposed that a pyrrolizidine alkaloid, N‐acetyl norloline, which is produced by the Max P endophyte, may be responsible for this new toxicity in horses. 相似文献
573.
DIDIER H. MATHON DVM PhD OLIVIER DOSSIN DVM PhD Diplomate ECVIM‐CA SOPHIE PALIERNE DVM PhD MATTHIEU CREMOUX DVM HERIBERTO RODRIGUEZ DVM PATRICIA MEYNAUD‐COLLARD DVM PhD JAN S. SUCHODOLSKI DVM PhD HERVE P. LEFEBVRE DVM PhD Diplomate ECVPT ANDRE AUTEFAGE DVM PhD Diplomate ECVS 《Veterinary surgery : VS》2009,38(8):967-974
Objective— To describe a laparoscopic‐sutured gastropexy technique in dogs and evaluate the tensile strength of the adhesion and effects on gastric function. Study Design— Experimental study. Animals— Female beagle dogs (n=7). Methods— A laparoscopic‐sutured gastropexy technique was evaluated by ex vivo tensile distraction tests 10 weeks after surgery. The effect of the adhesion on gastric emptying, mucosal permeability, and systemic inflammation were evaluated by monitoring the C‐reactive protein (CRP) and sucrose permeability, and by radiographic evaluation of gastric emptying 2 weeks before and 10 weeks after surgery. Results— Mean (±SD) tensile force to disrupt adhesions was 51.1±16.4 N. There was no significant postoperative increase in CRP concentration or change in sucrose permeability. The area under the curve representing the postprandial decrease in gastric radiographic area increased by 11% after gastropexy. Conclusions— This laparoscopic gastropexy technique had appropriate mechanical and functional characteristics with limited morbidity. Clinical Relevance— This laparoscopic‐sutured gastropexy provides adhesion strength comparable with other gastropexy techniques tested at 10 weeks postoperatively. Only minor changes in gastric emptying were observed 10 weeks after surgery. 相似文献
574.
MA Stornelli JC Reyna MC Stornelli R Nuñez Favre CA Savignone CM Tittarelli RL de la Sota 《Reproduction in domestic animals》2009,44(S2):287-290
The aim of this study was to asses the variation in the morphology of the seminal epithelium in relation to natural photoperiod in male cats. Tom cats (n = 240) were castrated every other week throughout the year. Each testis was fixed in Bouin's solution and cut into sections. The percentage of tubules with round spermatids (RS), elongated spermatids (ES), tailed spermatids (TS), mature spermatids (MS) and the number of Sertoli cells (SC) and Leydig cells (LC) were recorded in each sample. Testicles from males during short days (SHD) had a higher percentage of tubules with RS and ES compared to testicles from males during long days (LHD, 31.3 ± 0.6 vs 2.1 ± 0.6%, p < 0.001; 30.9 ± 0.7 vs 11.0 ± 0.7%, p < 0.001). Conversely, testicles from males during SHD had a lower percentage of tubules with TS and MS compared to testicles from males during LHD (24.5 ± 0.8 vs 29.7 ± 0.8%, p < 0.01; 13.1 ± 1.2 vs 57.0 ± 1.2%, p < 0.01). Furthermore, testicles from males during SHD had a higher number of SC and lower number of LC compared to testicles from males during LHD (11.4 ± 0.1 vs 8.0 ± 0.1%, p < 0.01; 19.2 ± 1.0 vs 38.0 ± 1.0%, p < 0.01). In conclusion, there are seasonal changes in testis cell morphology in the tom which may be related to seasonal sperm production. 相似文献
575.
Luis Otavio Brito Luis Alejandro Vinatea Arana Roberta Borda Soares William Severi Rayzza Helena Miranda Suzianny Maria Bezerra Cabral da Silva Maria Raquel Moura Coimbra Alfredo Olivera Gálvez 《Aquaculture International》2014,22(5):1649-1664
A 28-day indoor trial was conducted to evaluate the water quality, phytoplankton composition and growth of Litopenaeus vannamei in an integrated biofloc system with Gracilaria birdiae and Gracilaria domingensis. The experimental design was completely randomized with three treatments: control (shrimp monoculture); SB (shrimp and G. birdiae) and SD (shrimp and G. domingensis), all with three replicates. Random sampling was done (6 % of total population per experimental unit) to confirm white spot syndrome Virus (WSSV) infection using nested-PCR analysis due to suspicion of presence of the virus in the experiment (treatment and control groups). Shrimp L. vannamei (2.63 ± 0.10 g) were stocked in experimental tanks at a density of 425 shrimp m?3, and the Gracilaria was stocked at a biomass of 2.0 kg m?3. Shrimp mortality began in both the experimental and control groups at 10 days of culture. The integrated biofloc system (shrimp and seaweed) increased settleable solids (by 26–52 %); final weight (by 6–21 %); weekly growth (by 17–43 %); weight gain (by 17–43 %); specific growth rate (by 16–36 %); and yield (by 5–7 %) and decreased feed conversion ratio (by 21–28 %) and Cyanobacteria density about 16 % as compared to the control (shrimp monoculture). The use of red seaweed Gracilaria in an integrated biofloc system can enhance shrimp growth and reduce Cyanobacteria density in the presence of WSSV. 相似文献
576.
Francisco Gerson Araújo Mrcia Cristina Costa de Azevedo Gustavo Henrique Soares Guedes Wagner Uehara 《Ecology of Freshwater Fish》2022,31(1):45-59
Increases in temperatures over the last century, more intensively after the eighties, were recorded in several databases for the south-eastern Brazil. These increases are likely to change fish communities in aquatic systems by decreasing abundances, biomass and sizes of some species more sensitive to climate change. Reservoirs may be particularly susceptible to the effects of climate change, as they isolate previously connected areas limiting fish dispersal and migration, as well as increasing water temperature and thermal stratification. We assessed temporal changes in the abundance and biomass of the ichthyofauna in an isolate reservoir (inflowing waters from small tributaries in a highland region) aiming to associate changes with climate effects over three decades (1990, 2000, 2010). Two abundant native species, a loricariid Loricariichthys castaneus (Castelnau, 1855) and a cichlid Geophagus brasiliensis (Quoy & Gaimard, 1824), were selected to assess eventual response to climate changes in their geographical distribution in the Southeast Atlantic Hydrographic Region, considering different carbon emission scenarios using ecological niche models. A decrease in the densities and biomass of the ichthyofauna and of the two selected species were observed in both summer and winter over the three decades, coinciding with increases in temperatures. These decreases were correlated with increases in positive anomalies of temperature, which may be an indicator of climatic changes, although with low explanation of the data variation. The mean size of L. castaneus decreased between the nineties and 2010, whereas no significant trend was found for the size of G. brasiliensis. Our predictions of new area for future adequacy indicated a loss in the distribution area for both species (mainly for G. brasiliensis), considering the most pessimistic scenario for 2050 and 2070, possibly due to climatic changes. Both hydroelectric dams and global warming pose threats to freshwater fish diversity, and both will interact. Changes observed in the fish assemblage over the last decades were essential for an assessment of the consequences of global warming in this type of reservoir combining larger scale studies with future projections. 相似文献
577.
Sebastião Soares de Oliveira Neto Francisca Franciana Sousa Pereira Tiago Zoz Carlos Eduardo da Silva Oliveira Vânia Moda Cirino 《Journal of Agronomy and Crop Science》2023,209(1):83-93
Brazil is the world's largest producer of common beans (Phaseolus vulgaris L.). Drought stress harms the morphological and agronomic traits of beans. This study evaluates the reaction to water deficit in five genotypes of black beans. The experiment was conducted in the IDR-IAPAR-EMATER in Londrina-PR, Brazil. A split-plot design was used, with three replications. The genotypes were included in the subplots and the treatments with or without water deficit in the plots. Water deficit was induced on the pre-flowering stage and maintained for 20 days in the plots submitted to drought stress. For the growth analysis, plants were collected at 35, 54 and 70 days after emergence. At the stage of physiological ripeness, several morphological and yield traits were evaluated. The genotypes IPR Uirapuru and BRS Esplendor can be considered tolerant and used as a tolerant source to water deficit in common bean germplasm banks. The line LP 08-90 has morphological and agronomic adaptations efficient to overcome water deficit's effects, presenting a higher grain yield in both crop conditions, which indicates the success of black beans breeding to deal with water deficit. 相似文献