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101.
Analysis of fenbendazole residues in bovine milk by ELISA 总被引:1,自引:0,他引:1
Brandon DL Bates AH Binder RG Montague WC Whitehand LC Barker SA 《Journal of agricultural and food chemistry》2002,50(21):5791-5796
Fenbendazole residues in bovine milk were analyzed by ELISAs using two monoclonal antibodies. One monoclonal antibody (MAb 587) bound the major benzimidazole anthelmintic drugs, including fenbendazole, oxfendazole, and fenbendazole sulfone. The other (MAb 591) was more specific for fenbendazole, with 13% cross-reactivity with the sulfone and no significant binding to the sulfoxide metabolite. The limit of detection of the ELISA method in the milk matrix was 7 ppb for MAb 587 and 3 ppb for MAb 591. Fenbendazole was administered in feed, drench, and paste form to three groups of dairy cattle. Milk was collected immediately before dosing and then every 12 h for 5 days. The ELISA indicated that residue levels varied widely among individual cows in each group. Fenbendazole levels peaked at approximately 12-24 h and declined rapidly thereafter. Metabolites were detected at much higher levels than the parent compound, peaked at approximately 24-36 h, and declined gradually. Residue levels were undetectable by 72 h. The ELISA data correlated well with the total residues determined by chromatographic analysis, but the use of the two separate ELISAs did not afford an advantage over ELISA with the single, broadly reactive MAb 587. The ELISA method could be used to flag high-residue samples in on-site monitoring of fenbendazole in milk and is a potential tool for studying drug pharmacokinetics. 相似文献
102.
103.
Epilepsy in the dog--a comparative approach 总被引:1,自引:0,他引:1
J Barker 《The Journal of small animal practice》1973,14(5):281-289
A review of the current theories of the physiopathogenesis of the epilepsies is presented; emphasis is placed on the value of a more basic approach to the naturally–occuring seizure disorders of the dog, from both a clinical and electroencephalographic viewpoint. The comparative and veterinary rewards of such an approach are stressed. Résumé. On a présenté une revue des théories courantes de la physiopathogenèse des épilepsies. On a fait ressortir la valeur d'une approche plus fondamentale concernant les troubles d'attaque brusque se produisant naturellement chez le chien d'un point de vue à la fois clinique et électro-encephalographique. On a souligné les récompenses comparatives et vétérinaires d'une telle approche. Zusammenfassung. Eine nochmalige Obersicht der zur Zeit herrschenden Théorie von der Physiopathogenèse ùber Epilepsien wird vorgelegt; nachdrùcklich betont man den Wert von einer mehr fundamentalen Stellungsnahme zu den spontanen Epilepsieanfall-Stǒrungen des Hundes, von klinischer wie elektroenzephalographischer Hinsicht aus. Man betont die relativen und veterinǎren Belohnungen von solch einer Annàherung des Problems. 相似文献
104.
Steroid levels after intramuscular injection of testosterone propionate in the caprine. 总被引:2,自引:2,他引:0 下载免费PDF全文
Nine sexually mature intact grade does were injected intramuscularly with testosterone propionate and subsequent plasma steroid concentrations determined and male-like behavior recorded. The does received either 100 mg testosterone propionate every three days for six treatments, total dose 600 mg (N = 5); 50 mg testosterone propionate daily for eighteen days, total dose 900 mg (N = 2) or 10 mg testosterone propionate daily for eighteen days, total dose 180 mg (N = 2). The treatments induced male-like sex behavior, the intensity of which was related to the dose of exogenous testosterone used, the regimen of administration, and the plasma levels of testosterone. Exogenous testosterone treatment had minimal effect on the subsequent reproductive activity of the does. 相似文献
105.
Spontaneous gastric squamous cell carcinomas and other neoplasms in Greenland collared lemmings (Dicrostonyx groenlandicus). 下载免费PDF全文
Malignant neoplasms were present in 39/66 Dicrostonyx groenlandicus of varying ages, examined from a laboratory colony. The presence of multiple neoplasms in some resulted in an overall average of 1.15 tumors/affected animal. Gastric squamous papillomas were present in nine, and locally invasive or metastatic gastric squamous cell carcinomas in a further 36 animals. Three mammary adenocarcinomas, one pancreatic islet cell tumor, one probable pancreatic adenocarcinoma and one adrenal cortical adenoma were also seen in lemmings with gastric tumors. Two others had mammary adenocarcinoma alone, and one animal had bilateral Harderian gland adenocarcinoma. Lesions resembling glomerulonephrosis of rats were seen in 23/51 animals whose kidneys were examined. These findings were not considered artefacts of captivity since concurrent gastric squamous cell carcinoma, mammary adenocarcinoma and glomerulonephrosis were present in the single animal examined directly from the wild at Eskimo Point, Northwest Territories. 相似文献
106.
Response of mink, skunk, red fox and raccoon to inoculation with mink virus enteritis, feline panleukopenia and canine parvovirus and prevalence of antibody to parvovirus in wild carnivores in Ontario. 下载免费PDF全文
Mink virus enteritis, feline panleukopenia and canine parvovirus-2 were inoculated separately into groups of raccoon, mink, red fox and striped skunk. Raccoons were highly susceptible to mink virus enteritis and feline panleukopenia, with animals developing clinical illness, and several dying within six to ten days of inoculation with lesions typical of parvovirus infection. Both viruses were shed in high titre in the feces of infected raccoons, and high antibody titres were stimulated. Raccoons inoculated with canine parvovirus-2 showed no signs; shedding of virus was sporadic though moderate titres of antibody developed. Mink inoculated with mink virus enteritis and feline panleukopenia developed signs and lesions of early parvovirus infection. No signs or significant lesions followed canine parvovirus-2 inoculation. Shedding of virus was heavy (mink virus enteritis) or sporadic (feline panleukopenia and canine parvovirus-2), though good serological responses were elicited to all three viruses. Red fox showed no signs of infection, shed all three viruses only sporadically, and the serological response was strong only to feline panleukopenia. Skunks developed low antibody titres, but no signs, and did not shed virus. Antibody to parvovirus was found in 79.2% of 144 wild red foxes; 22.3% of 112 wild raccoons; 1.3% of 157 wild skunks and 6/7 coyotes in southern Ontario. The likely significance of these viruses to wild and captive individuals and populations of these carnivores is discussed. 相似文献
107.
A device is described which can produce single drops of liquids in uniform sizes. Drop size can be adjusted, and with an aqueous solution of a non-ionic surfactant (“Agral”; 1 ml/litre) sizes 160–490 μm diam. were produced. Suitable techniques of calibration are given. The device is a useful research tool for study of the effects of form of deposit on herbicide performance. 相似文献
108.
Colin E. Harvey 《The Journal of small animal practice》1977,18(3):163-168
Three dogs and one cat were diagnosed at the University of Pennsylvania Veterinary Hospital as having parotid salivary duct rupture and fistula as a result of previous surgery. Sialography confirmed the diagnosis. Two animals were treated by ligation, and two by anastomosis of the parotid duct. All four animals returned to normal after treatment. 相似文献
109.
In vitro antimicrobial sensitivity of Mycoplasmas isolated from the bovine genital tract. 总被引:1,自引:1,他引:0 下载免费PDF全文
R B Truscott O Onoviran H L Ruhnke N A Fish C A Barker 《Canadian journal of veterinary research》1975,39(4):416-420
The in vitro antimicrobial sensitivity of 14 mycoplasma and 13 ureaplasma strains isolated from the genital tracts of bulls was examined. It was found that at relatively low concentrations, tetracycline, declomycin and tylosin were lethal to both types of organisms. Lincospectin, berenil, streptomycin and erythromycin were lethal to mycoplasmas but were only inhibitory to the ureaplasma strains at the same concentrations. Polymyxin B and novobiocin were ineffective at the levels tested. 相似文献
110.
Four adult wethers (45 kg) with permanent ruminal and abomasal cannulae were used in a repeated measures Latin-square arrangement of treatments to quantitate the effects of diet concentrate level and sodium bicarbonate (NaHCO3) on site and extent of forage fiber digestion in the gastrointestinal tract. Experimental diets consisted of Kentucky-31 tall fescue hay, soybean meal and a semi-purified concentrate mixture in ratios of 95:5:0, 76:4:20, 57:3:40 and 38:2:60; NaHCO3 represented 0 or 7.5% of the concentrate mixture. Ruminal digestion (% of intake) of neutral detergent fiber (NDF) and hemicellulose decreased linearly (P less than .05), whereas acid detergent fiber (ADF) digestion responded in a cubic (P less than .05) fashion to increasing concentrate level; NaHCO3 improved ruminal digestion of NDF (P less than .10) and ADF (P less than .05), but not hemicellulose. Post-ruminal digestion (% of rumen non-degraded) of NDF and ADF tended to increase, whereas hemicellulose digestion responded in a cubic (P less than .05) fashion to increasing concentrate level; NaHCO3 decreased (P less than .05) post-ruminal digestion of all fiber fractions. Total tract digestion of NDF and ADF showed a cubic (P less than .05) response, whereas hemicellulose digestion responded in a quadratic (P less than .05) fashion to increasing concentrate level; NaHCO3 had no effect on total tract digestion of any fiber fraction. Correlations of ruminal hemicellulose digestion with mean pH (r = .33; P = .07) and minimum pH (r = .30; P = .09) were attained in a 24-h feeding cycle.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献