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91.
The aim of this study was to determine the viability and cardiorespiratory effects of the association of epidural alpha-2 adrenergic agonists and lidocaine for ovariohysterectomy (OH) in bitches. Forty-two bitches were spayed under epidural anesthesia with 2.5 mg/kg body weight (BW) of 1% lidocaine with adrenaline (CON) or in association with 0.25 mg/kg BW of xylazine (XYL), 10 μg/kg BW of romifidine (ROM), 30 μg/kg BW of detomidine (DET), 2 μg/kg BW of dexmedetomidine (DEX), or 5 μg/kg BW of clonidine (CLO). Heart rate (HR), respiratory rate (fR) and arterial pressures were monitored immediately before and every 10 min after the epidural procedure. Blood gas and pH analysis were done before, and at 30 and 60 min after the epidural procedure. Animals were submitted to isoflurane anesthesia if they presented a slightest sign of discomfort during the procedure. Time of sensory epidural block and postoperative analgesia were evaluated. All animals in CON and DEX, 5 animals in ROM and CLO, 4 animals in XYL, and 3 in DET required supplementary isoflurane. All groups, except CLO, showed a decrease in HR. There was an increase in arterial pressures in all groups. Postoperative analgesia lasted the longest in XYL. None of the protocols were totally efficient to perform the complete procedure of OH; however, xylazine provided longer postoperative analgesia than the others.  相似文献   
92.
Line transect distance sampling (LTDS) can be applied to either trails or roads. However, it is likely that sampling along roads might result in biased density estimates. In this paper, we compared the results obtained with LTDS applied on trails and roads for two primate species (Callithrix penicillata and Callicebus nigrifrons) to clarify whether roads are appropriate transects to estimate densities. We performed standard LTDS surveys in two nature reserves in south-eastern Brazil. Effective strip width and population density were different between trails and roads for C. penicillata, but not for C. nigrifrons. The results suggest that roads are not appropriate for use as transects in primate surveys, at least for some species. Further work is required to fully understand this issue, but in the meantime we recommend that researchers avoid using roads as transects or treat roads and trails as covariates when sampling on roads is unavoidable.  相似文献   
93.

Key message

Climate factors affect seed biomass production which in turn influences autumn wild boar spatial behaviour. Adaptive management strategies require an understanding of both masting and its influence on the behaviour of pulsed resource consumers like wild boar.

Context

Pulsed resources ecosystem could be strongly affected by climate. Disantangling the role of climate on mast seeding allow to understand a seed consumer spatial behaviour to design proper wildlife and forest management strategies.

Aims

We investigated the relationship between mast seeding and climatic variables and we evaluated the influence of mast seeding on wild boar home range dynamics.

Methods

We analysed mast seeding as seed biomass production of three broadleaf tree species (Fagus sylvatica L., Quercus cerris L., Castanea sativa Mill.) in the northern Apennines. Next, we explored which climatic variables affected tree masting patterns and finally we tested the effect of both climate and seed biomass production on wild boar home range size.

Results

Seed biomass production is partially regulated by climate; high precipitation in spring of the current year positively affects seed biomass production while summer precipitation of previous year has an opposite effect. Wild boar home range size is negatively correlated to seed biomass production, and the climate only partially contributes to determine wild boar spatial behaviour.

Conclusion

Climate factors influence mast seeding, and the negative correlation between wild boar home range and mast seeding should be taken into account for designing integrated, proactive hunting management.
  相似文献   
94.
Myxobolus porofilus sp. n. is described infecting the visceral cavity of Prochilodus lineatus (Valenciennes, 1836) cultivated in S?o Paulo State, Brazil. The plasmodial form of the parasite is 3-5 mm in length and appeared compressed between the wall of the visceral cavity and the pyloric caecum, reposing on this organ. The spores are small (length 5.7 +/- 0.3 microm, width 4.8 +/- 0.2 microm; mean +/- SD) and round to elliptical in frontal view. The valve surfaces are smooth and have sutural folds. The polar capsules are ovoid, small (length 1.6 +/- 0.1 microm, width 1.1 +/- 0.1 microm) and equal in size. The polar filaments have three turns aligned perpendicularly to the longitudinal axis of the capsule. A conspicuous polar filament pore is arranged at the anterior end of the spore. The only reaction observed upon histological analysis was the presence of a capsule of connective tissue surrounding the plasmodia. This is the first report of a myxosporean parasite in the Prochilodontidae.  相似文献   
95.
In this report, we describe Henneguya arapaima n. sp., a parasite of the gill arch and gall bladder of Arapaima gigas (pirarucu) collected in the Araguaia River, in the municipality of Nova Crixás, Goiás State, central Brazil. The plasmodia were white, round or ellipsoidal and measured 200-600mum. Parasite development was asynchronous and the mature spores were fusiform and had smooth wall. The spores measurements were (range, with means+/-S.D. in parentheses): total length-48.4-53.1mum (51.6+/-3.4mum), body length-13.5-15.2mum (14.2+/-0.8mum), body width-5.1-6.1mum (5.7+/-0.5mum), body thickness-4.7-5.3mum (4.9+/-0.2mum) and caudal process length-38.0-41.2mum (38.3+/-2.9mum). The polar capsules were elongated and of unequal size, with lengths of 6.3-6.8mum (6.5+/-0.2) and 6.2-6.6mum (6.3+/-0.1) for the longest and shortest axes, respectively. Capsule width was 1.4-1.6mum (1.5+/-0.1). Histological analysis showed that the plasmodia occurred in the tunica adventitia of the gall bladder and were delimited by a thin capsule of connective tissue. In the gill arch, the plasmodia were also surrounded by connective tissue similar to the endomesium of striated skeletal muscle cells. Sixty-five juvenile specimens of A. gigas weighing 1.0-25.0kg were examined, 17 (26.1%) of which were infected. Of these, 14 (82.3%) had cysts in the gall bladder, two (11.7%) had cysts in the gill arch and only one (5.9%) had cysts in both organs. When the fish were grouped by weight, the prevalence of infection in fish weighing up to 10.0kg (20.7%) was significantly lower than in fish weighing 10.1-25.0kg (50%) (G=3.93; d.f.=1; p<0.05).  相似文献   
96.
Integrative taxonomy, a multi‐disciplinary approach adding modern techniques to traditional morphology‐based methods (e.g. molecular and morphological criteria), can play an important role in bioinvasion research to identify introduced taxa, discover pathways of introduction and inform authorities to control and prevent future introductions. The present study is the first on introduced populations of Callosciurus, Asiatic tree squirrels, known as potentially invasive species in Europe (Italy, Belgium and France). We combined molecular (mitochondrial DNA markers: CoxI, D‐loop) and morphometric analysis on skulls, comparing them to the widest morphological and molecular datasets ever assembled for Callosciurus. Squirrels collected in Italy and Belgium share the same haplotypes and skull characteristics, but are conspicuously different from the French population in Antibes. Genetic data revealed close similarity between French squirrels and Pallas's squirrels, Callosciurus erythraeus, from Taiwan, China. Italian and Belgian squirrels formed an independent taxonomic lineage in genetic analyses, whose taxonomic rank needs further investigation. The morphological and morphometric characteristics of these 2 populations are, however, similar to known specimens assigned to Callosciurus erythraeus. These results may indicate a common origin for the populations found in Belgium and Italy. In contrast, French specimens suggest an independent introduction event of squirrels originating from Asia.  相似文献   
97.
98.
Salinity is one of the most important growth-limiting factors for most crops in arid and semi-arid regions; however, the use of plant growth-promoting rhizobacteria isolated from saline soils could reduce the effects of saline stress in crops. This study aimed to evaluate the efficiency of plant growth-promoting rhizobacteria (PGPRs), isolated from the rhizosphere of halophile plants, for the growth, Na+/K+ balance, ethylene emission, and gene expression of wheat seedlings (Triticum aestivum L.) grown under saline conditions (100 mmol L-1 NaCl) for 14 d. A total of 118 isolates obtained from saline soils of the deserts of Iran were tested for their capacity as PGPRs. Out of the 118 isolates, 17 could solubilize phosphate (Ca3(PO4)2), 5 could produce siderophores, and 16 could synthesize indole-3-acetic acid. Additionally, PGPRs were also evaluated for aminocyclopropane-1-carboxylate deaminase activity. A pot experiment was conducted to evaluate the ability of 28 PGPR isolates to promote growth, regulate Na+/K+ balance, and decrease ethylene emissions in plants. The most efficient PGPRs were Arthrobacter aurescens, Bacillus atrophaeus, Enterobacter asburiae, and Pseudomonas fluorescens. Gene expression analysis revealed the up-regulation of H+-PPase, HKT1, NHX7, CAT, and APX expression in roots of Enterobacter-inoculated salt-stressed plants. Salt-tolerant rhizobacteria exhibiting plant growth-promoting traits can facilitate the growth of wheat plants under saline conditions. Our results indicate that the isolation of these bacteria may be useful for formulating new inoculants to improve wheat cropping systems in saline soils.  相似文献   
99.
Nitrogen (N) and potassium (K) are the most required nutrients for corn and wheat production. Increasing the N application rate usually boosts crop yields. However, many uncertainties remain for K management. Potassium deficiency results in yield losses, but K application rate based on the percentage of K+ in the cation exchange capacity (CEC) is doubtful, especially in soil with high CEC. A field trial was conducted to examine the effects of KCl application before sowing corn and wheat, by raising the percentage of K+ in CEC at pH 7.0 (CECpH7.0) to approximately 2.5%, 3.5%, and 4.5%, and adding N as a topdressing (75, 150, and 225 kg ha-1 to corn and 40, 80, and 120 kg ha-1 to wheat) on the nutrition and yield of corn and wheat under a continuous no-till system (30 years). Exchangeable K+ content increased in the topsoil (0-20 cm depth) up to 7.2 mmolc dm-3 after K application at the highest rate, which, however, did not result in significant increases in nutrient uptake and yields for both corn and wheat. The N application rate positively affected the uptake and removal of all macronutrients by corn and wheat. Applying N as a topdressing increased yields of corn and wheat by up to 83% and 22%, respectively. Our results suggest that in the soil with a high CECpH7.0 (162.1 mmolc dm-3), the recommendation for K application made by considering the percentage of K+ in the CECpH7.0 may result in excessive application of K fertilizer to crops with high K-recycling potential grown under a continuous no-till system.  相似文献   
100.
Journal of Pest Science - In South America, especially in Brazil, four members of the Spodoptera complex, Spodoptera albula (Walker, 1857), S. cosmioides (Walker, 1858), S. eridania (Stoll, 1782),...  相似文献   
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