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排序方式: 共有170条查询结果,搜索用时 258 毫秒
61.
de Carvalho MA Santos PS Nogueira SS Lessa F Almeida Vdos A Le?a-Júnior NF Salvarani FM Lobato FC Nogueira-Filho SL 《Journal of zoo and wildlife medicine》2011,42(4):732-734
An outbreak of necrotic enteritis caused by Clostridium perfringens type C was diagnosed in captive collared (Pecari tajacu) and white-lipped (Tayassu pecari) peccaries housed in the Laboratory of Applied Ethology of Universidade Estadual de Santa Cruz located in Ilhéus, State of Bahia, Brazil. Four collared peccaries and three white-lipped peccaries, all juveniles (25-105 days old), were affected. For all affected animals, lethargy and inappetance were followed by sudden death within 24 hours. Histopathology of intestinal wall, culture of C. perfringens type C, and the identification of beta-toxin from intestinal content confirmed the diagnosis. 相似文献
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63.
This paper describes the reproductive performance of Penueus schmitti kept under controlled conditions in a maturation facility of a commercial shrimp farm. A total of 369 females and 368 males of wild P. schmitti were used to form 9 broodstock groups. Unilateral ablation was performed on females only. Although females were not tagged, the total number of mated females ( N = 533) indicates that rematuration of the ovaries did occur. Only 9 mated females (1.69%) did not spawn and only 22 mated females (4.20%) of the remaining 524 cases did not produce viable spawns. These results indicate that a large number of viable spawns (94.18%) can be expected from P. schmitti . A minimum latency period of 6 days for the ovaries to attain full development was observed twice. The highest mating frequency occurred between the 46th and 60th days after unilateral ablation, but mating frequency remained above 2% until the 90th day. The average number of nauplii/female/spawn was 78,961 ( N = 524) and the average fertilization rate of the eggs was 73.12% ( N = 297). Usually when the pair of the spermatophores is dislodged from the thelycum of the mated female, a small sperm mass still remains between the third pair of walking legs. This condition did not show any negative effect on the fertilization rate of the eggs and nauplii production. Mating behavior displayed by P. schmitti is also described and includes three distinctive phases: a) chasing, b) mating and c) post-mating chase. 相似文献
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65.
Marcela Pacola Tiara Moraes Guimarães João Paulo Gonsiorkiewicz Rigon Lucas Moraes Jacomassi João William Bossolani Josiane Viveiros Gabriela Ferraz de Siqueira Patrícia Pereira Dias Juliano Carlos Calonego Carlos Alexandre Costa Crusciol 《Soil Use and Management》2023,39(4):1388-1402
Combining deep tillage (DT) with lime application at greater depths may improve sugarcane yield. The objective of this study was to evaluate the impact of conventional tillage (CT) and DT systems and liming on sugarcane productivity and soil physical attributes. The experiment was conducted in a clayey-textured Rhodic Hapludox soil cultivated with sugarcane for two growing seasons (first and third ratoons) using a randomized block design with four treatments and four repetitions. The treatments consisted of DT without liming (DT0), DT with liming (DT2), CT without liming (CT0) and CT with liming (CT2). In addition to sugarcane stalk and sugar yields, macroporosity (MA), microporosity (MI), total soil porosity (TP), weighted average diameter (WAD), aggregate stability index (ASI), soil penetration resistance (SPR), pH, potential acidity (H + Al), total soil organic carbon (SOC), particulate organic carbon (POC), mineral-associated organic carbon (MOC), calcium (Ca) and magnesium (Mg) were analysed. DT2 promoted the best soil conservation effect on sugarcane. In general, DT, regardless of lime application, reduced SOC and POC in soil surface layer. Nevertheless, in the long term, localized lime addition resulted in significant reductions in compaction, reaching values below 2 MPa. The soil fertility improvement provided by DT2 promoted increased sucrose concentrations and stalks yield. Considering that there was an improvement in the physical quality and fertility of soil for better plant development, the deep tillage with localized lime addition can be considered an effective alternative for sugarcane cultivation. 相似文献
66.
Modeling the Exchanges of Energy, Water, and Carbon Between Continents and the Atmosphere 总被引:19,自引:0,他引:19
PJ Sellers RE Dickinson DA Randall AK Betts FG Hall JA Berry GJ Collatz AS Denning HA Mooney CA Nobre N Sato CB Field A Henderson-Sellers 《Science (New York, N.Y.)》1997,275(5299):502-509
Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, and momentum across the land-atmosphere interface to be specified. These fluxes are calculated by submodels called land surface parameterizations. Over the last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations of the global soil-vegetation-atmosphere transfer system as advances in plant physiological and hydrological research, advances in satellite data interpretation, and the results of large-scale field experiments have been exploited. Some modern schemes incorporate biogeochemical and ecological knowledge and, when coupled with advanced climate and ocean models, will be capable of modeling the biological and physical responses of the Earth system to global change, for example, increasing atmospheric carbon dioxide. 相似文献
67.
68.
N.S.M.L. Miqueleto S.C. Rahal F.S. Agostinho E.G.M. Siqueira F.A.P. Araújo A.O. El-Warrak 《Veterinary journal (London, England : 1997)》2013,195(2):210-215
This study investigated kinematic patterns in clinically normal German Shepherd dogs (GSDs) compared to those with hip dysplasia and with no clinical signs of lameness. Two groups of GSDs, including 10 clinically healthy dogs (G1) and 10 with hip dysplasia (G2), were trotted on a treadmill at a constant speed. Kinematic data were collected by a 3-camera system and analysed by a motion-analysis program. Flexion and extension joint angles and angular velocities were determined for the shoulder, elbow, carpal, hip, stifle, and tarsal joints.Within each group, the differences between the right and left limbs in all kinematic variables were not significant. Minimum angle, angular displacement and minimum angular velocity did not differ between groups. Significant differences were observed in the maximum angular velocity and maximum angle of the hip joint (dysplastic > healthy), and in the maximum angular velocity of the carpal joint (healthy > dysplastic). It was concluded that, when trotting on a treadmill, dysplastic dogs with no signs of lameness may present joint kinematic alterations in the hind as well as the forelimbs. 相似文献
69.
Matos MF Leite LI Brustolim D de Siqueira JM Carollo CA Hellmann AR Pereira NF da Silva DB 《Fitoterapia》2006,77(3):227-229
The cytotoxic effects of seven constituents isolated from Duguetia glabriuscula were evaluated against Hep2 human larynx carcinoma cells. The cytotoxicity exhibited by beta-sitosterol was as strong as that of cis-platin. (+)-Alloaromadendran-10,14beta-diol caused inhibition of cellular growth with IC50 values lower than 25 microg/ml, a feature that was considered as revealing significant activity. Polycarpol showed borderline cytotoxicity, whereas the other compounds were inactive. 相似文献
70.
JB Siqueira RO Pinho SEF Guimarães T Miranda Neto JD Guimarães 《Reproduction in domestic animals》2010,45(6):1122-1125
This case study reported the presence of short tail sperm defect in the semen of three Nelore breed bulls. The sperm presented 0% of motility in the three animals evaluated and a total of 70%, 61% and 34% of pathologies of the intermediate piece of the tail respectively for animals 1, 2 and 3. It was identified that animals 2 and 3 had high degree of inbreeding, although no relationship was found with animal 1. Animal 2 was the only one that presented inbreeding coefficient (6.25%). His half‐sib (animal 3) and animal 1, from the same herd, had shown no inbreeding, showing that inheritance is not the only determinant factor for its incidence on Nelore males. 相似文献