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排序方式: 共有1076条查询结果,搜索用时 24 毫秒
971.
972.
973.
Garrido Frenich A González Rodríguez MJ Martínez Vidal JL Arrebola FJ Hernández Torres ME 《Pest management science》2005,61(5):458-466
A simple method for multi-residue analysis of pesticides by low-pressure gas chromatography-tandem mass spectrometry (LP-GC-MS-MS) has been validated in compost samples. The pesticide residues were extracted from the lyophilised samples with organic solvent by stirring. No sample clean-up was required prior to the analysis. The method was applied to determine the fate of two organochlorine pesticides (lindane and endosulfan) and two organophosphates (malathion and chlorpyrifos-methyl) during the composting process in the reactor of a pilot plant. Malathion, chlorpyrifos-methyl and lindane residues almost fully disappeared after 8 days of maturation in the reactor, while endosulfan residues were only partially degraded. Alongside this, a study of natural disappearance of the pesticides was carried out in the laboratory and a characteristic time profile was traced for each pesticide class. 相似文献
974.
Antimicrobial susceptibility of clinical strains of Streptococcus suis isolated from pigs in Spain 总被引:6,自引:0,他引:6
Vela AI Moreno MA Cebolla JA González S Latre MV Domínguez L Fernández-Garayzábal JF 《Veterinary microbiology》2005,105(2):143-147
The antimicrobial susceptibility of 151 clinical Streptococcus suis strains isolated from diseased pigs in Spain was determined by a microdilution method. Isolates were mostly susceptible to beta-lactam antimicrobials, aminoglycosides, enrofloxacin, novobiocin and spectinomycin. More than 87% of the S. suis isolates were resistant to tetracyclines, sulphonamides, macrolides and clindamycin. Strains of serotype 9 were significantly more resistant than strains of serotype 2 (P<0.05) to tylosin (94% versus 77%) and clindamycin (94% versus 64%). Eighty-seven percent of the S. suis isolates were resistant to at least four antimicrobials and nine isolates (6%) were resistant to at least six antimicrobials. The most frequently identified multidrug pattern involved resistance against tetracyclines, sulphonamides, macrolides and lincosamides, with 69% of the isolates exhibiting this resistotype. Fifteen out of the 22 strains of serotype 2 (68.2%), and 84 out of the 98 of the strains of serotype 9 (85.7%) exhibited this resistotype, indicating its widespread distribution among the strains of the two most frequently isolated serotypes. 相似文献
975.
Assunção P De la Fe C Kokotovic B González O Poveda JB 《Veterinary research communications》2005,29(6):453-462
The study was conducted to investigate the mycoplasmal flora in the lungs of pigs with enzootic pneumonia at Gran Canaria
(Spain). From 54 pneumonic lungs collected at an abattoir, 85 isolates were cultivated. On the basis of cultural and biochemical
characteristics, the isolates were preliminarily identified as Mycoplasma species. Using different species-specific PCRs, 40, 27, 11 and 7 of the isolates were identified as M. hyorhinis, M. hyopneumoniae, M. hyosynoviae and M. flocculare, respectively. Nine of the M. hyopneumoniae cultures were found to be in mixed culture with M. flocculare as demonstrated by PCR. By use of a M. flocculare antiserum it was possible to eliminate M. flocculare from M. hyopneumoniae mixed cultures. This study is the first report on isolation of porcine mycoplasmas at Gran Canaria (Spain). 相似文献
976.
Ulcerative enteritis is found in a wide range of avian hosts but has not been described in psittacine birds. This case report describes ulcerative enteritis in four lories (two Trichoglossus sp. and two Eos sp.) that were found dead without any previous sign of disease. Macroscopically, all four birds showed good body condition. The only remarkable finding was a moderate dilatation of the small intestine with the presence of multiple yellow foci. Histologically, multiple ulcers extended into the submucosa and were filled with necrotic debris; bacteria and fibrin were observed in the intestinal mucosa. The liver and spleen exhibited a multifocal fibrinoid necrosis associated with a very moderate inflammatory reaction. Microbiological isolation revealed colonies of Clostridium colinum and Clostridium perfringens in the intestinal tract of the investigated birds. 相似文献
977.
Santiago-Moreno J Gómez-Brunet A González-Bulnes A Toledano-Díaz A Malpaux B López-Sebastián A 《Domestic animal endocrinology》2005,28(4):416-429
This study compares morphological changes, performed with real-time transrectal ultrasonography, of testis and accessory glands and seasonal endocrine changes in a wild (Mouflon) and a domesticated (Spanish Merino) breed of sheep. In Mouflons, the maximum plasma testosterone concentrations, testicular diameter and vesicular gland size occurred synchronously during autumn (P < 0.001). In Merino rams the highest circulating levels of testosterone (P < 0.05) and maximum testicular diameter (P < 0.001) occurred during summer, with no seasonal variations in vesicular and bulbourethral glands. The seasonal changes in plasma concentrations of prolactin were not correlated with annual variations in testicular and glandular size in neither wild nor domestic species. No differences were observed between both species for the seasonal pattern of prolactin secretion and mean amplitude of melatonin. Wide differences in reproductive patterns between wild and domestic types of rams do not appear to be attributed to seasonal changes in prolactin and melatonin secretion. 相似文献
978.
Pharmacokinetics of marbofloxacin after intravenous and intramuscular administration to ostriches 总被引:3,自引:0,他引:3
de Lucas JJ Rodríguez C Waxman S González F Uriarte I San Andrés MI 《Veterinary journal (London, England : 1997)》2005,170(3):364-368
The pharmacokinetics of marbofloxacin was investigated after intravenous (IV) and intramuscular (IM) administration, both at a dose rate of 5 mg/kg BW, in six clinically healthy domestic ostriches. Plasma concentrations of marbofloxacin was determined by a HPLC/UV method. The high volume of distribution (3.22+/-0.98 L/kg) suggests good tissue penetration. Marbofloxacin presented a high clearance value (2.19+/-0.27 L/kgh), explaining the low AUC values (2.32+/-0.30 microgh/mL and 2.25+/-0.70 microgh/mL, after IV and IM administration, respectively) and a short half life and mean residence time (t(1/2 beta)=1.47+/-0.31 h and 1.96+/-0.35 h; MRT=1.46+/-0.02 h and 2.11+/-0.30 h, IV and IM, respectively). The absorption of marbofloxacin after IM administration was rapid and complete (C(max)=1.13+/-0.29 microg/mL; T(max)=0.36+/-0.071 h; MAT=0.66+/-0.22 h and F (%)=95.03+/-16.89). 相似文献
979.
980.
Prevalence of intestinal parasites in dogs under veterinary care in Maracaibo, Venezuela 总被引:3,自引:0,他引:3
Ramírez-Barrios RA Barboza-Mena G Muñoz J Angulo-Cubillán F Hernández E González F Escalona F 《Veterinary parasitology》2004,121(1-2):11-20
The prevalence of intestinal parasites in dogs presented to the Veterinary Policlinic of the University of Zulia (PVU) was measured between January and December 2001. A total of 614 fecal samples were evaluated by the fecal flotation method. One or more species of parasites was identified in 218 (35.5%) dogs. The parasites most frequently detected were: Ancylostoma spp. (24.5%), Toxocara canis (11.4%) and Isospora spp. (8.1%). Single parasitic infections were present in 149 (24.3%) dogs. The age distribution of intestinal parasites in dogs less than 1 year old had a higher overall prevalence than those dogs over 12 months of age. There was no significant difference in the prevalence between male (38.9%) and female (31.7%) dogs. There was a significantly (P < 0.05) greater prevalence of parasites in mixed-breed dogs (40.3%) as compared with pure-breed dogs (30.8%). A significant difference (P < 0.05) was detected between the general prevalence of January and December compared to August. 相似文献