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排序方式: 共有276条查询结果,搜索用时 31 毫秒
11.
Robson RV Alves Tatiana Soares Elinaldo FL Bento Ricardo S Roldan‐Filho Brbara SS Souza Marcele KN Lima Jssica S Nascimento Luana CBB Coelho Roberto A S Thmarah A Lima Gabriel GA Gonalves Fbio A Brayner Luiz C Alves Daniela MAF Navarro Thiago H Napoleo Patrícia MG Paiva 《Pest management science》2020,76(2):730-736
12.
Antonia Euflosina Dos Santos Iracema Andrade Nascimento 《Aquaculture (Amsterdam, Netherlands)》1985,47(4):335-352
Laboratory experiments were undertaken to determine the optimal environmental conditions and some of the other factors concerned in the development of Crassostrea rhizophorae embryos.Critical variables such as the number of spermatozoa per ovocyte during fertilization, the time of fertilization after gamete liberation, egg density, temperature and salinity were related to the proportion of normal D-larvae of C. rhizophorae in the resulting broods.The highest proportion of normal D-larvae was obtained at concentrations of 500–5000 spermatozoa/ovocyte, under conditions of 25‰ salinity at 25 ± 1°C. The optimal density of eggs, for the production of normal D-larvae, was 104?4 × 104 ovocytes/l. If fertilization was delayed for more than 45 min after liberation of spermatozoa the proportion of normal D-larvae was greatly reduced. The experiments demonstrated that the temperature for developing embryos should be below 30°C. At 20 and 25°C there was a high proportion of normal D-larvae 24 h after fertilization. The ideal salinity for embryonic development in C. rhizophorae was 25–37‰. Below a salinity of 16‰, less than 2.5% of the D-larvae were normal. 相似文献
13.
Lidiane Cristina Gonçalves de Sandre Hellen Buzollo Thiago Matias Torres do Nascimento Lígia Maria Neira Eduardo Gianini Abimorad Rosangela Kiyoko Jomori Carlos Ducatti Maria Célia Portella Dalton José Carneiro 《Journal of the World Aquaculture Society》2016,47(1):113-122
This study evaluated the application of stable isotopes of carbon as an alternative and more accurate method to determine gastrointestinal transit time (GTT) in fish by comparing it to the inert marker method. The stable isotope method detects alterations of the normal carbon flow in a biological system by analyzing naturally occurring isotopes of carbon, contrary to studies based on conventional techniques that apply external markers to the diet to determine GTT through visual observation of the color change in feces. Therefore, 320 pacu, Piaractus mesopotamicus juveniles were reared in 32 tanks under two different temperatures (25 and 29 C). The pacu juveniles received two different diets, one based on ingredients derived from C3 photosynthetic cycle plants and the other based on C4 plant ingredients, both containing titanium oxide (TiO2) as a marker. After 40 d, the isotopic signature of the diets was changed, and the marker was replaced by chromic oxide (Cr2O3). In the isotopic technique, the feces were analyzed to determine the exchange in the isotopic ratio of carbon δ13C. Both methods found that GTT was faster (nearly 6 h) in fish at 29 C when using the C4/C3 feeding strategy and slower in fish at 25 C using the C3/C4 strategy (15 h by inert marker and 18 h by the isotopic method). In conclusion, GTT determination in pacu juveniles using the stable isotope technique exhibits the same accuracy obtained with the inert marker method at temperatures suitable (nearly 29 C) for the metabolism of these animals. 相似文献
14.
Frias AF Mársico F Gómez de Segura IA Nascimento PR Nascimento A Soares JH Almosny NR 《Veterinary anaesthesia and analgesia》2003,30(4):193-201
Objective To characterize responses to different doses of propofol in horses pre‐medicated with xylazine. Animals Six adult horses (five females and one male). Methods Each horse was anaesthetized four times with either ketamine or propofol in random order at 1‐week intervals. Horses were pre‐medicated with xylazine (1.1 mg kg?1 IV over a minute), and 5 minutes later anaesthesia was induced with either ketamine (2.2 mg kg?1 IV) or propofol (1, 2 and 4 mg kg?1 IV; low, medium and high doses, respectively). Data were collected continuously (electrocardiogram) or after xylazine administration and at 5, 10 and 15 minutes after anaesthetic induction (arterial pressure, respiratory rate, pH, PaO2, PaCO2 and O2 saturation). Anaesthetic induction and recovery were qualitatively and quantitatively assessed. Results Differences in the quality of anaesthesia were observed; the low dose of propofol resulted in a poorer anaesthetic induction that was insufficient to allow intubation, whereas the high dose produced an excellent quality of induction, free of excitement. Recorded anaesthesia times were similar between propofol at 2 mg kg?1 and ketamine with prolonged and shorter recovery times after the high and low dose of propofol, respectively (p < 0.05; ketamine, 38 ± 7 minutes; propofol 1 mg kg?1, 29 ± 4 minutes; propofol 2 mg kg?1, 37 ± 5 minutes; propofol 4 mg kg?1, 50 ± 7 minutes). Times to regain sternal and standing position were longest with the highest dose of propofol (32 ± 5 and 39 ± 7 minutes, respectively). Both ketamine and propofol reversed bradycardia, sinoatrial, and atrioventricular blocks produced by xylazine. There were no significant alterations in blood pressure but respiratory rate, and PaO2 and O2 saturation were significantly decreased in all groups (p < 0.05). Conclusion The anaesthetic quality produced by the three propofol doses varied; the most desirable effects, which were comparable to those of ketamine, were produced by 2 mg kg?1 propofol. 相似文献
15.
Salle CT Guahyba AS Wald VB Silva AB Salle FO Nascimento VP 《British poultry science》2003,44(2):211-217
1. Although the poultry industry uses state-of-the-art equipment and up-to-date services, in Brazil it generally makes decisions involving all its production variables based on purely subjective criteria. This paper reports the use of artificial neural networks to estimate performance in production birds belonging to a South Brazilian poultry farm. 2. Recorded data from 22 broiler production breeder flocks were obtained, from April, 1998 to December, 1999, which corresponded to 689 data lines of weekly recordings. 3. These data were processed by artificial neural networks using the software NeuroShell 2 version 4.0 (Ward Systems Group). The artificial neural network models generated were compared and selected based on their largest determination coefficient (R2), lowest Mean Squared Error (MSE), as well as on a uniform scatter in the residual plots. The authors conclude that it is possible to explain the performance variables of production birds, with the use of artificial neural networks. 4. The method allows the decisions made by the technical staff to be based on objective, scientific criteria, allows simulations of the consequences related to these decisions, and reports the contribution of each variable to the variables under study. 相似文献
16.
da Rocha AC da Silva AB de Brito AB Moraes HL Pontes AP Cé MC do Nascimento VP Salle CT 《Avian diseases》2002,46(3):749-753
Sixty-three Escherichia coli strains isolated from broilers with respiratory problems were examined for virulence factors, hemolysin synthesis ability, motility, hemagglutination capacity, operon pap presence, colicin production, and serum resistance. The capacity to hemagglutinate guinea pig erythrocytes was found in 53 (84.1%) of the samples, but only 30 (47.6%) agglutinated chicken erythrocytes. D-mannose-sensitive hemagglutination against guinea pig erythrocytes was found in 19 (30.2%) samples and against chicken erythrocytes, in 15 (23.8%) samples, whereas the D-mannose-resistant hemagglutination with guinea pig erythrocytes was found in 34 (54%) samples, and 13 of these (20.6%) showed this characteristic against chicken erythrocytes. Operon pap, P fimbria codifier, was detected in 26 samples in a total of 34 D-mannose-resistant samples. Colicin production was observed in 55 (87.3%) of the strains, and 41.8% presented V colicin production. Of the samples analyzed, 56 (88.9%) presented serum resistance, six (9.5%) were intermediate, and only one (1.6%) was sensitive to the action of the complement. The diversity of virulence profiles detected in the samples in this study explains in part the multifactorial characteristics of avian colibacillosis. 相似文献
17.
N.M. Ocarino DVM MS A.E. Silva DVM MS S.A. Frana DVM M.A. Rachid DVM PhD E.F. Nascimento DVM PhD M.S. Palhares DVM PhD V.A. Gheller DVM PhD R. Serakides DVM PhD 《Journal of Equine Veterinary Science》2006,26(4):168-170
A case of renal tubular carcinoma with bone metaplasia is reported in a 20-year-old male, mixed breed horse having a history of weight loss and hematuria. This report includes the clinical signs, macroscopic and microscopic lesions, and the immunohistochemical findings of this neoplasm. 相似文献
18.
Sousa Larissa Nascimento Batista Samira Pereira Silva Samara Santos da Silva Rômulo Fylipe Sarmento Wlysse Ferreira Mota Rinaldo Aparecido Brasil Arthur Willian Lima Amaku Marcos Feitosa Thais Ferreira Vilela Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the... 相似文献
19.
Campos FR Januário AH Rosas LV Nascimento SK Pereira PS França SC Cordeiro MS Toldo MP Albuquerque S 《Fitoterapia》2005,76(1):26-29
Crude extracts and fractions of Bertholletia excelsa stem barks were tested for trypanocidal activity. Acetone and methanol extracts showed significant in vitro trypanocidal activity against trypomastigote form of Trypanosoma cruzi since in the concentration of 500 microg/ml, the parasites were reduced in 100% and 90.3% respectively, whereas the triterpene betulinic acid pure isolated from hexane extract presented 75.4%. 相似文献
20.
The spectral data of a new Δ7,22 sterol, 24S-ethyl-5α-cholesta-7,22E-dien-3α-ol β-galactopyranoside, isolated from the bulbs of Autonoë madeirensis, are reported. 相似文献