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101.
SUMMARY An Isoprenyl guanldine, galegine, was isolated from the Western Australian sedge Schoenus asperocarpus (Cyperaceae). Synthetic galegine was shown to reproduce the clinical and pathological features of poisoning by this plant. Preliminary results suggest that the massive thoracic effusion observed in sedge poisoning is the result of a direct effect on pulmonary vascular permeability. 相似文献
102.
Objective To investigate tissue residues of two longacting oxytetracycline (OTC) preparations in cattle.
Design A randomised drug residue trial.
Two hundred and forty beef cattle in 24 groups of ten.
Procedure Two blind-coded 200 mg/mL OTC preparations were used in five treatment regimens of various combinations of injection sites (from one to five) and administrations (one or two). Five cattle from each group were slaughtered at 21, 30 and 60 days after injection and the injection site, urine, kidney and diaphragm muscle analysed for residues.
Results The OTC concentration exceeded the maximum residue limit in kidney in animals slaughtered 21 days after treatment, which is the prescribed withholding period. Concentration at the injection site was much greater than the maximum residue limit 30 days post-treatment, but not 45 days post-treatment. The residue was smaller when OTC had been injected in multiple sites. There was no difference between the two OTC preparations.
Conclusion A review of the maximum injection volume, site of injection and the withholding period is needed for long-acting OTC formulations. 相似文献
Design A randomised drug residue trial.
Animals
Two hundred and forty beef cattle in 24 groups of ten.
Procedure Two blind-coded 200 mg/mL OTC preparations were used in five treatment regimens of various combinations of injection sites (from one to five) and administrations (one or two). Five cattle from each group were slaughtered at 21, 30 and 60 days after injection and the injection site, urine, kidney and diaphragm muscle analysed for residues.
Results The OTC concentration exceeded the maximum residue limit in kidney in animals slaughtered 21 days after treatment, which is the prescribed withholding period. Concentration at the injection site was much greater than the maximum residue limit 30 days post-treatment, but not 45 days post-treatment. The residue was smaller when OTC had been injected in multiple sites. There was no difference between the two OTC preparations.
Conclusion A review of the maximum injection volume, site of injection and the withholding period is needed for long-acting OTC formulations. 相似文献
103.
Prevalence of antimicrobial resistance and resistance genes in faecal Escherichia coli isolates recovered from healthy pets 总被引:2,自引:0,他引:2
Costa D Poeta P Sáenz Y Coelho AC Matos M Vinué L Rodrigues J Torres C 《Veterinary microbiology》2008,127(1-2):97-105
Faecal samples of healthy dogs (n=39) and cats (n=36) obtained in Northern Portugal were seeded on Levine agar plates, and two Escherichia coli isolates per sample were recovered (78 of dogs and 66 of cats). The susceptibility to 16 antimicrobial agents was tested in this series of 144 E. coli isolates. Almost 20% of them showed tetracycline resistance and 12 and 15% presented ampicillin or streptomycin resistance, respectively. The percentage of resistance to the other antimicrobial agents was in all cases below 4%, and no resistant isolates were detected for ceftazidime, imipenem, cefoxitin or amikacin. Two isolates (from one dog) showed cefotaxime-resistance and harboured both the CTX-M-1 and OXA-30 beta-lactamases. A bla(TEM) gene was detected in 12 of 17 ampicillin-resistant isolates, the aac(3)-II gene in the three gentamicin-resistant isolates, aadA in 7 of 22 streptomycin-resistant isolates, and tet(A) and/or tet(B) gene in all 28 tetracycline-resistant isolates. The gene encoding class 1 integrase was detected in six E. coli isolates, including the four trimethoprim-sulfamethoxazole-resistant isolates and those two harbouring CTX-M-1 and OXA-30 beta-lactamases; different gene cassette arrangements were identified: dfrA1+aadA1 (two isolates), dfrA12+orfF+aadA2 (two isolates) and bla(OXA30)+aadA1 (two isolates). One amino acid change in GyrA protein (Ser83Leu or Asp87Tyr) was detected in four nalidixic acid-resistant and ciprofloxacin-susceptible isolates and two amino acid changes in GyrA (Ser83Leu+Asp87Asn) and one in ParC (Ser80Ile) were identified in one nalidixic acid- and ciprofloxacin-resistant isolate. Faecal E. coli isolates of healthy pets could be a reservoir of antimicrobial resistance genes. 相似文献
104.
SM Rhind 《Reproduction in domestic animals》2008,43(S2):15-22
Pollutants of many chemical classes, derived primarily from anthropogenic activities, are ubiquitous in the environment, persistent, biologically available and can exert adverse effects on the reproductive and other, indirectly related, physiological systems. Food is generally considered to be the major route of animal exposure in vertebrate species but the relative contributions of other routes of exposure such as through lungs, gills or skin are not well studied and may be of importance for certain animal groups, depending on their immediate environment. Animals are particularly sensitive to exposure during developmental stages but the pattern of exposure to chemicals is likely to be different to that of adults. Quantification of the risk posed by the ingestion of pollutants in food is complex and depends on many factors including species, diet composition, duration of exposure to the food, efficiency of pollutant absorption, subsequent metabolism, sensitivity of target organs and stage of development. While the effects of high doses of single chemicals are proven, dietary exposure to pollutants generally involves prolonged, low-level exposure to a large number of compounds, each of which has different chemical characteristics, exerts different biological effects and is present at varying concentrations. Thus, while exposure to pollutants through feed is undoubtedly a significant risk factor for many species and may be the most important one for many terrestrial vertebrates, other routes of exposure may be more important in other groups. 相似文献
105.
Renata Pereira da Silva-Marques Joanis Tilemahos Zervoudakis Luciana Keiko Hatamoto-Zervoudakis Pedro Ivo José Lopes da Rosa e Silva Núbia Bezerra do Nascimento Matos Andresa Lazzarotto Feliciano Rones Goulart de Paula Júnior Luciano da Silva Cabral 《Tropical animal health and production》2018,50(4):715-720
Supplementation of animals in the rainy season is essential to maximise weight gain. Thus, the objective was to evaluate the effects of supplementation with low-, medium- and high-protein levels on nutritional parameters of grazing beef cattle in the rainy season. Eight rumen-cannulated Nellore bulls (437 kg body weight) were used in a 4?×?4 double Latin square design with four supplements and four experimental periods. The treatments were mineral supplement (ad libitum) and supplements with low-protein (LPSU), medium-protein (MPS) and high-protein (HPS) levels, providing 106, 408 and 601 g/day of crude protein (CP), respectively. There was no difference (P?>?0.05) between treatments for dry matter and forage intake, ruminal pH, ruminal ammonia nitrogen (RAN) at time 0 (before supplementation) and microbial protein yield. Animals on MPS had a higher (P?>?0.05) intake and digestibility of CP, higher RAN levels (3 and 6 h after supplementation), increased nitrogen intake and a better nitrogen balance than animals on LPSU. The HPS provided higher (P?>?0.05) RAN at time 6 and a better nitrogen balance when compared with MPS. We therefore infer that the high-protein supplement positively impacts nitrogen metabolism and efficiency in grazing beef cattle during the rainy season. 相似文献
106.
Alane P. O. Monte Jamile M. Santos Vanúzia G. Menezes Bruna B. Gouveia Thae L. B. G. Lins Ricssio S. Barberino Joozito L. Oliveira Nathalie J. Donfack Maria Helena T. Matos 《Reproduction in domestic animals》2019,54(9):1169-1176
This study analysed the effect of growth differentiation factor‐9 (GDF‐9) on the in vitro culture of isolated ovine secondary follicles. The follicles were cultured in α‐MEM supplemented with BSA, insulin, glutamine, hypoxanthine, transferrin, selenium, ascorbic acid and FSH (α‐MEM+—control medium) or α‐MEM+ supplemented with 1, 10, 50 or 100 ng/ml GDF‐9. Next, the oocytes were destined to in vitro maturation (IVM). After 12 days of culture, there were no differences regarding the percentage of normal follicles, antrum formation and follicle diameter between the treatments (p > 0.05). The rates of fully grown oocytes (≥110 µm) were higher (p < 0.05) in 100 ng/ml GDF‐9 than other treatments, except for 10 ng/ml of GDF‐9 (p > 0.05). Treatment containing 100 ng/ml GDF‐9 showed higher (p < 0.05) mitochondrial activity than the control group. Moreover, 100 ng/ml GDF‐9 showed more oocytes in MI than α‐MEM+, 1 or 50 ng/ml GDF‐9 (p < 0.05). In conclusion, 100 ng/ml GDF‐9 increased the growth, mitochondrial function and meiotic resumption of oocytes from in vitro grown sheep secondary follicles. 相似文献
107.
Jssica de Matos Nunes Amanda Valle Pinhatti Gilsane Lino von Poser Sandra Beatriz Rech 《Industrial Crops and Products》2009,30(2):329-332
The effect of long-term fertilization supply on biomass yield and secondary metabolites accumulation was assessed in vegetative and reproductive parts of acclimatized field grown plants of Hypericum polyanthemum, an endemic species of southern Brazil. Fertilization caused positive responses in plant growth with biomass increment of vegetative and reproductive parts, proportional to the MS solution concentration (25%, 50% and 100%), whereas the chemical analyses indicated that the supply of fertilization solution did not alter the concentration of 6-isobutyryl-5,7-dimethoxy-2,2-dimethyl-benzopyran (HP1), 7-hydroxy-6-isobutyryl-5-methoxy-2,2-dimethyl-benzopyran (HP2), uliginosin B as well as total phenolic compounds (TPCs), and increased the accumulation of 5-hydroxy-6-isobutyryl-7-methoxy-2,2-dimethyl-benzopyran (HP3) in all fertilization regimes. 相似文献
108.
Fabio Rossi Cavalcanti Mario Lucio Vilela Resende Joo Paulo Matos Santos Lima Joaquim Albenisio Gomes Silveira Jos Tadeu Abreu Oliveira 《Physiological and Molecular Plant Pathology》2006,68(4-6):198-208
The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion® 50 WG (0.2 g l−1)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO2 assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions. 相似文献
109.
Antover Panazzolo Sarmento Alisson Carraro Borges Antonio Teixeira Matos 《Water, air, and soil pollution》2012,223(3):1065-1071
In this study, the role of Cyperus sp. was evaluated for removal of pollutants from swine wastewater. Vertical-flow pilot scale constructed wetlands (CWs) operating with a hydraulic retention time (HRT) of 72 h were monitored in a greenhouse, located in Viçosa, Brazil. Significant differences were observed for the following parameters: Kjeldahl nitrogen, total phosphorus, alkalinity and electric conductivity, with averages removals of 37.5 and 28.5%, 55.9 and 44.4%, 30.2 and 25.6 and 26.1% and 22.9% (for planted and unplanted CWs, respectively). The rate of dry matter yield from Cyperus sp. was 7.5 g?m?2 day?1, and the nutrient uptake capacities were 21.8, 2.1, 14.0 and 0.9 g?m?2 of N, P, K and Na, respectively. Evapotranspiration (2.7 mm day?1) was statistically higher in the planted CWs. Plants in the CWs are important for achieving high nutrient removal. 相似文献
110.
M.F. Schmitz D.G.G. Matos I. De Aranzabal D. Ruiz-Labourdette F.D. Pineda 《Biological conservation》2012,149(1):122-135
Specific land uses, many of them considered as traditional practices, have contributed to nature conservation in that they have given rise to a valued landscape and a high degree of biological and cultural diversity. The result is the rural cultural landscape, also characterised by its multi-functionality, stability and adaptation to local conditions. Nonetheless, the abandonment of rural cultural landscapes constitutes the current trend in many regions.Although one way to preserve rural cultural landscapes involves establishing protected areas, management often forgets, or even restricts, the traditional rural activities that had contributed to the high conservation values recognised in these areas.In the present paper we applied a quantitative model to examine changes in rural cultural landscapes and in the socioeconomy of local populations following the establishment of a protected area. We formalised the relationship of dependence between landscape change and socioeconomy by means of multivariate ordination analysis and multiple regression calculation. The simple equation obtained shows the socioeconomic parameters that best account for change in the landscape and indicate their sign and importance. The results show that providing Regional Park protection status has not prevented the decline of traditional farming activities and, in turn, ecological succession has led to an intense shrub encroachment process. Such a change could be considered to be the result of a nature protection policy inspired by ideas of naturalness and wilderness. Our model also helps us to establish and formalise the dependence of the cultural landscape upon a socio-cultural system, which is currently undergoing rapid change, and brings us to consider the parameters of this change as indicators for management. 相似文献