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11.
P. M. Bizzotto A. L. Godinho V. Vono B. Kynard H. P. Godinho 《Ecology of Freshwater Fish》2009,18(3):461-472
Abstract – Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the 'nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. 相似文献
12.
Godinho KS Rae A Windsor GD Tilt N Rowan TG Sunderland SJ 《Veterinary therapeutics : research in applied veterinary medicine》2005,6(2):96-112
The efficacy of tulathromycin in the treatment of bovine respiratory disease (BRD) due to Mycoplasma bovis was determined following experimental infection. Two highly pathogenic strains of M. bovis (with minimum inhibitory concentration values for tulathromycin of 1 and >64 microg/ml) were inoculated into 145 calves. Four days after inoculation, calves with clinical BRD were treated subcutaneously with saline or tulathromycin (2.5 mg/kg). Compared with saline, BRD-related withdrawals, peak rectal temperatures, and lung lesion scores were significantly lower for tulathromycin-treated calves (P < .01). Tulathromycin was highly effective in the treatment of BRD due to M. bovis in calves regardless of the minimum inhibitory concentration of the challenge strain (1 or >64 microg/ml). 相似文献
13.
Y. Sato N. Fenerich-Verani J R. Verani L J S. Vieira & H P. Godinho 《Aquaculture Research》2000,31(2):189-193
Experiments on induced spawning of the anostomid fish Leporinus elongatus Val. 1849, an important neotropical migratory fish, were carried out at Três Marias Fish Hatchery Station, State of Minas Gerais, Brazil, to develop a reliable protocol for inducing breeding in this species. L. elongatus matures reliably in earthen ponds to a point at which final maturation can be induced with carp pituitary extract. The following data were recorded: number of extruded eggs (g ova?1) = 2444 ± 740; stripped ova weight:body weight = 13.1 ± 2.9%; retained (ovulated but not stripped) ova weight:body weight = 5.8 ± 2.6%; initial fertility = 318.7 × 103± 149.2 × 103; final fertility = 229.3 × 103± 129.3 × 103; egg fertilization rate = 63.8 ± 16.4% and ≈ 229 000 larvae per female. The relationships between stripping time and water temperature and between hatching and water temperature were given by the same exponential equation t= ae–bT. The relationships between body weight (Wt) and initial (IF) and final fertility (FF) were expressed by the equations: IF =?9382 + 322 047 × Wt (r2= 0.84); FF =?40 780 + 265 062 × Wt (r2= 0.75). 相似文献
14.
Ana Maria Coser Hugo Godinho Dirceu Ribeiro 《Aquaculture (Amsterdam, Netherlands)》1984,37(4):387-390
This paper reports an initial trial to cryopreserve semen from two freshwater South American fishes, the curimbatá (Prochilodus scrofa) and the dourado (Salminus maxillosus). Motility and duration of motility were observed in curimbatá and dourado fresh sperm. Semen mixed with extender (0.8% NaCl) was frozen using vials (1 ml) with subsequent storage in liquid nitrogen. Samples were thawed in 1% NaHCO3 or in 0.8% NaCl solutions. Post-thawing motility and duration of motility were verified. A simple extender consisting of 0.8% NaCl plus 10% DMSO was able to initiate motility in fresh spermatozoa. The percentage of motile cells and duration of motility were similar in both thawing solutions, but lower than in fresh sperm. 相似文献
15.
Godinho KS Sarasola P Renoult E Tilt N Keane S Windsor GD Rowan TG Sunderland SJ 《The Veterinary record》2007,160(1):22-25
An epidural puncture was performed using the lumbosacral approach in 18 dogs, and the lack of resistance to an injection of saline was used to determine that the needle was positioned correctly. The dogs' arterial blood pressure and epidural pressure were recorded. They were randomly assigned to two groups: in one group an injection of a mixture of local anaesthetic agents was made slowly over 90 seconds and in the other it was made over 30 seconds. After 10 minutes contrast radiography was used to confirm the correct placement of the needle. The mean (sd) initial pressure in the epidural space was 0.1 (0.7) kPa. After the injection the mean maximum epidural pressure in the group injected slowly was 5.5 (2.1) kPa and in the group injected more quickly it was 6.0 (1.9) kPa. At the end of the period of measurement, the epidural pressure in the slow group was 0.8 (0.5) kPa and in the rapid group it was 0.7 (0.5) kPa. Waves synchronous with the arterial pulse wave were observed in 15 of the dogs before the epidural injection, and in all the dogs after the epidural injection. 相似文献
16.
In humans, regulatory T (T reg) cells are known to play a critical role in both the regulation of immune homoeostasis and the progression of cancer. However, there is little information about the identification, characterization and the function of T reg cells in canine tumours. We identified T reg cells in 28 canine seminoma samples using a Forkhead box P3 (Foxp3) antibody and investigated the relationship between T reg cell infiltration and histopathological features of classical and spermatocytic seminomas (SE and SS, respectively). The Foxp3 protein showed nuclear immunostaining in infiltrating lymphocytes, and Foxp3+ cells were diffused or focally distributed in seminoma tissues. Foxp3+ cells were frequently present in the SS histotype, in seminomas that showed no evidence of tumour cell invasion into the vessels and in seminomas showing a diffuse growth pattern with three cell types. Neither the SE/SS histotype nor the histopathological features of the tumour correlated with Foxp3+ cell counts. These results indicate that Foxp3+ T reg cells may be associated with a less malignant histological phenotype or may not play a critical role in the immune response of canine seminomas. Moreover, Foxp3+ T reg cells may be associated with SS seminoma, but further studies, involving a larger number of samples, are required to better understand whether these cells play a critical role in the immune response in canine seminomas. This is the first report to demonstrate the characteristics of T reg cell infiltration in canine seminoma. 相似文献
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18.
Polar stratospheric clouds (PSCs) are important for the chemical activation of chlorine compounds and subsequent ozone depletion. Solid PSCs can form on sulfuric acid tetrahydrate (SAT) (H2SO4·4H2O) nuclei, but recent laboratory experiments have shown that PSC nucleation on SAT is strongly hindered. A PSC formation mechanism is proposed in which SAT particles melt upon cooling in the presence of HNO3 to form liquid HNO3-H2SO4-H2O droplets 2 to 3 kelvin above the ice frost point. This mechanism offers a PSC formation temperature that is defined by the ambient conditions and sets a temperature limit below which PSCs should form. 相似文献
19.
Silvio C��sar Godinho Teixeira Roberta Louren?o Ziolli M?nica Regina da Costa Marques Daniel Vidal P��rez 《Water, air, and soil pollution》2011,219(1-4):297-301
This study investigated pyrene adsorption on two contrasting Brazilian soils: a Kandiudult and a Vertisol. It was found that the time taken to reach thermodynamic equilibrium depended on the soil type. The curves for different pyrene-to-soil mass ratios for Vertisol soil showed significant differences. This is probably related to the presence of 2:1 clays that may increase the adsorption of pyrene due to the resulting interlamellar space. The adsorption of pyrene on the Kandiudult showed, in general, good agreement with the Langmuir isotherm. In the case of the Vertisol, there was good agreement with the linear isotherm. The kinetic model that best explains the adsorption in Kandiudult was the pseudo second-order model. For the Vertisol, the Morris Weber model best explains the behavior of pyrene. 相似文献
20.
Microhabitat use by Iberian nase Chondrostoma polylepis and Iberian chub Squalius carolitertii in three small streams, north-west Portugal 总被引：2，自引：0，他引：2
Abstract – Microhabitat use of Iberian nase Chondrostoma polylepis (Steindachner 1865) and Iberian chub Squalius carolitertii (Doadrio 1988) was studied in three small streams of the Lima basin, north-west Portugal. Measurements were made for 210 and 248 individuals, respectively, distributed in two size classes, based on fish ages, during winter, spring, summer and autumn 1998. Both species moved to shallow and slow-flowing microhabitats in summer and autumn, but this mainly reflected seasonal variation in microhabitat availability. Larger individuals of both species used deeper and lower percentage cover areas than smaller conspecifics, however significant ontogenetic differences were only found for water velocity. Different patterns of nonrandom microhabitat use were displayed by both cyprinids. Larger I. nase were in deeper and more discovered waters than those available in the habitat, whereas I. chub was over-represented in slow-flowing areas. There was no evidence of interspecific competition for microhabitat, therefore it is unlikely that spatial resource was limited during the present study. 相似文献