ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00872.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Monoclonal antibodies have been produced using two haptens, zeranol‐7‐hemisuccinate coupled to bovine serum albumin and zeranol‐16‐carboxypropyl ether coupled to human serum albumin. An assessment of cross‐reactivity demonstrated that the monoclonal antibody raised against the 7‐hemisuccinate derivative reacted with zeranol (100%), talernol (12%), zearalenone (17%), zearalanone (100%) and α‐and ß‐zearalenol (17% and<0.01%, respectively). In contrast the antibodies to the 16‐carboxypropyl ether derivative reacted only with zeranol (100%) and also with a α‐zearalenol (13‐16%). All monoclonal antibodies were more specific than the polyclonal antibodies raised to the same haptens by conventi

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00873.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Halothane MAC (the minimum alveolar concentration of halothane to produce anaesthesia in 50% of the animals tested) was determined to be 0.92 ± 0.16 volumes % in eight English Pointer dogs. Alterations in halothane MAC induced by an intravenous bolus of xylazine (1.1 mg/kg) and then tolazoline (5 mg/kg) was determined in each dog following control (halothane MAC) measurement. Following xylazine administration, MAC significantly decreased to 0.57 ± 0.023%. Immediately following determination of the xylazine‐halothane MAC value in each dog, tolazoline was administered and the halothane requirement (MAC) was again assessed. Halothane MAC significantly increased to 1.24 ± 0.036%. Tolazoline administration induced immediate arousal in the xylazine‐halothane anaesthetized dogs requiring a rapid increase in halothane concentration to maintain anaesthesia. Thus, the administration of tolazoline, an alpha adrenergic antagonist, following xylazine administration significantly increased the anaesthetic requirement (MAC) of halothane. Xylazine, an alpha 2 adrenergic agonist, decreased halothane anaesthetic requirement (MAC) in the eight dogs studied. These results are consistent with the hypotheses that stimulation of central alpha 2 receptors is the mechanism by which xylazine produces sedation and that inhibition of CNS excitatory neurotransmitter release decreases halothane anaesthetic requirement. In contrast, the increase in halothane requirement and arousal from xylazine‐halothane anaesthesia that occurred following i.v. tolazoline administration indicates an increase in CNS excitatory neurotransmitter

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00874.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Forty dogs (20 treated, 20 controls) were utilized to evaluate a new treatment for naturally acquired canine scabies. A liquid concentrate formulation of amitraz was diluted and applied as a sponge‐on therapy. Ninety‐four percent of the dogs treated with the scabicide were cleared of mites and returned to clinical normality with a single topical treatment; one dog was retreated, cleared of mites and was also returned to normality. All dogs treated with the miticide responded clinically, therefore the treatment also may be useful when trial therapy is necessary to differentially diagnose the disease. The miticide was well tolerated by all dogs, and there was no evidence of dermal or ocular irritation. Topical treatment with the liquid concentrate was efficacious and safe as a therapy for naturally acquired canine scabies. Placebo controls did not improve clinically and these animals retained their mite populati

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00875.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The minimal inhibitory concentrations (MIC) of carbenicillin, ticarcillin and BL‐P 1654 for gram‐negative udder pathogens were determined using the agar plate dilution method. The MIC of the drugs for 50% and 90% of the isolates examined ranged forEscherichia coli and Aerobacter spp.from 1.56 to 25 μg/ml, and forKlebsiellaspp. andPseudomonasspp. from 3.12 to 50 μg/ml. TheSerratiaspp. were relatively non‐susceptible for the drugs studied (MIC greater than 50μg/ml).Each drug was administered intravenously at5g and 15 g per cow to different groups of cows with normal and inflamed quarters of the udder. Distribution and elimination kinetic parameters calculated from serum drug level data were very similar to those of other beta‐lactam antibiotics. Although drug concentrations in milk from inflamed quarters were higher than in milk from normal quarters, they were considerably below the MIC for the majority of gram‐negative udder pathogens. The data suggest that parenteral treatment of gram‐negative udder infections with carbenicillin, carfecillin, ticarcillin and BL‐P 1654 at the dose levels used in the present study is unlikely to result in a bacteriological cure and would probably be clinic

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00876.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Sodium penicillin G was administered intravenously (4545 IU/kg) to calves on the day of birth (12‐24 h old) and at 5, 10, and 15 days of age. Serum was collected at varying intervals for 120 min after injection and analysed for penicillin G. The mean total body clearance (ClB) of penicillin G on the day of birth was 2.98 ml/min/kg compared to 4.83 ml/min/kg at 5 days, 3.11 ml/min/kg at 10 days and 4.65 ml/min/kg at 15 days of age. Clearances at 5 and 15 days were significantly (P<0.05) higher than on the day of birth. The half‐life(t1/2ß), however, did not change significantly over the 15‐day period of the study. These results indicate that the newborn calf has an appreciable ability to excrete penicillin G before it is 24 h old, and that total body clearance of the antibiotic increases rapidly in the immediate postnatal

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00877.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

Germ‐free, day‐old chickens were colonized with aLactobacillus fermentumstrain isolated from poultry which was able to inactivatein vitroerythromycin and other macrolide and lincosamide antibiotics. Similar control chickens were colonized with a non‐degradingL. fermentumstrain. Only in chickens colonized with the non‐degrading strain were blood levels considered to be therapeutically active achieved with erythromycin in the drinking water.Five groups of broiler chickens of different age originating from three farms all possessed an erythromycin‐degrading crop flora. In none of these were therapeutic blood levels attained when erythromycin was given in the drink

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00878.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

A 2% aqueous solution of methylene blue was administered as a single intravenous (i.v.) bolus injection (10 mg/kg) to six lactating cows and seven lactating goats and as a continuous i.v. drip to five lactating goats. The same dose was administered as a 10% solution by intramammary infusion to five lactating goats. Blood and milk samples collected at various times after these treatments were assayed for the drug by a colorimetric method. Methylene blue, a highly charged molecule (pKa<1), passed readily from blood into milk; drug concentrations in milk 4‐36 h after the single i.v. bolus injection were higher than those in blood. When examined at constant methylene blue levels in blood, a milk‐blood ratio of 5: 1 was observed. After intramammary infusion, the drug passed quickly into systemic circulation, peaked at3h and was still detectable in blood12h after infusion. The drug appeared in the urine within 15min after intramammary infusion. The rapid movement of the drug across the blood‐milk barrier cannot be explained on the basis of its known physicochemical properties or according to the pH‐pKapassive diffusion

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00879.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The minimal inhibitory concentrations of penicillin G, ampicillin, gentamicin, erythromycin and rifampicin were determined for nine strains ofCorynebacterium equi.The effect of combinations of any two of these antibiotics on the killing of these strains was determined at antibiotic concentrations achievable in horses using recommended drug dosages (ampicillin 4.0 μg/ml, gentamicin 1.0 μg/ml and erythromycin 0.25 μg/ml). Penicillin G was used at 4.0 μg/ml and rifampicin at 0.063 μg/ml. The combinations of gentamicin with erythromycin or rifampicin gave antagonistic effects on killing compared to either drug alone. Combinations of erythromycin with rifampicin or penicillin showed synergistic effects, as did penicillin‐gentamicin. All other combinations, and a triple combination of penicillin‐rifampicin‐erythromycin, showed additive ef

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00880.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY

摘要:

The presence of cyclooxygenase products of arachidonic acid metabolism in carrageenin‐induced inflammatory exudate was investigated in ponies using two models. In the first model, an inflammatory response was stimulated by injecting carrageenin into subcutaneously implanted polypropylene tissue cages and exudates were collected at five predetermined times between 3 and 48 h. In the second model, exudates were harvested at 6, 12 and 24 h from carrageenin‐impregnated polyester sponges which had also been inserted beneath the skin. Prostaglandin (PG) E2, thromboxane (TX) B2and the stable breakdown‐product of prostacyclin (PGI2), 6‐keto‐PGF1α, in exudates were measured by radioimmunoassay (RIA); PGE2‐like and PGF2α‐like activities were bioassayed following an acid‐lipid extraction technique which provided a recovery rate of 78%. Agreement between RIA and bioassay was within acceptable limits. In Model 1, using RIA, mean PGE2concentration reached 197 ng‐ml‐1at 12 h decreasing to<12 ng‐ml‐1at 24 h. Mean TXB2and 6‐keto‐PGF1α levels were highest at 48 h (22.3 and 34.2 ng‐ml‐1, respectively) after considerable fluctuations and with wide standard errors prior to this time. In the sponge model, however, PGE2levels were surprisingly low for each group (mean 12.8 ng‐ml‐1at 12 h) and TXB2and 6‐keto‐PGF1αwere similarly lower (means of 3.3 and 8.1 ng‐ml‐1respectively at 12 h). Mean total leucocyte counts and total protein concentrations were increased in both models after carrageenin stimulus. PGF2αwas not detected in measurable quantities in any exudate. It is concluded that PGE2, TXB2and PGI2could be regarded as possible mediators of acute

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1984.tb00881.x

出版商:Blackwell Publishing Ltd    

年代:1984

数据来源: WILEY