摘要:

The prototype of a commercial ELISA test kit designed for fentanyl determination in human urine has been evaluated for screening fentanyl in horse urine and plasma. The measurement of fentanyl after intravenous (2 mg) and intramuscular (0.25 mg) administration in undiluted plasma was not reproducible while accurate quantification of fentanyl in urine greatly depends on the composition of the horse urine. The ELISA assay, however, is simple and could be successfully used for quantitative measurements in diluted urine and for rapid qualitative screening for fentanyl in large numbers of urine samples.

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00633.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Treatment of buffalo calves (Bubalus bubalis) at different times after birth demonstrated that transmission ofToxocara vitulorumfrom the cow to the calf via milk occurs in all calves during the first 2 days after birth, decreases to 53% by 6 days, 10% by 8–9 days and 2% from Day 10 onwards. This may be because the larvae are no longer in the milk or because the calf has become resistant to the establishment of a new infection. The result also emphasizes the importance of mammary transmission of the parasite. Against immature parasites the efficacy of pyrantel and levamisole was 97%; febantel was 100% on one farm, only 35% on another; piperazine 42% and thiabendazole 35%. Santonin was ineffective in four calves. Against mature parasites the efficacy of pyrantel was 100%; febantel was 100% on one farm, only 35% on another; oral levamisole 83%; cutaneous levamisole 73%; oxfendazole 89%; and piperazine 57%. Nevertheless, piperazine reduced the infection to levels which were probably not pathogenic. In general, the efficacy against mature parasites was similar to that against immature parasites. Treatment of 10–16‐day‐old calves with an anthelmintic, which is effective against immature parasites, is recommended. This procedure greatly reduces contamination of the environment and also precludes the pathogenic effect of a large number of immature or mature pa

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00634.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

This study investigated whether enhanced metabolic responsiveness to p‐adrenergic stimulation might explain the liability of the stress‐sensitive pig to develop an acidosis during stressful situations. Blood lactate, pH,Pco2and heart rate response to an intravenous infusion of isoprenaline were examined in three lines of pentobarbitone anaesthetized, atropinized pigs. The lines were Pietrain × Hampshire which had been selected over eight generations for a positive reaction to the halothane test (stress‐sensitive); Pietrain x Hampshire which had been selected over eight generations for no reaction to the halothane test (stress‐resistant) and British Landrace which had been selected over four generations for a positive halothane reaction (stress‐sensitive). The metabolic responses to isoprenaline were greater in the stress‐sensitive Pietrain × Hampshire line than the stress‐resistant line. The stress‐sensitive Landrace pigs, however, had smaller changes in pH andPco2in response to isoprenaline than the stress‐resistant Pietrain × Hampshire pigs. This inconsistent trend across the three lines led to the conclusion that enhanced P‐adrenergic responsiveness was not the likely cause

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00635.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The pharmacokinetics and metabolism of sulphadimidine (SDM) following intravenous administration of 100 mg/kg were studied in seven dwarf preruminant kids at 12 weeks of age, and again at the ruminant stage, when the animals were 18 weeks old. The persistence of SDM in 18‐week‐old kids was prolonged in comparison to the 12‐week‐old animals: a lower total body clearance and a prolonged elimination of SDM were obtained in the older animals. The renal clearance values of SDM and its metabolites were the same at both ages. The decrease of SDM clearance is related to the significant reduction in SDM hydroxylation at the older age. The reduced oxidative hepatic metabolism may result from the sexual maturation of t

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00636.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Single dose, subconjunctival injections of procaine penicillin using either skin or conjunctival routes of administration were evaluated in order to compare the duration of antibacterial concentrations at the site ofMoraxella bovisinfection. Samples of conjunctival sac fluid (CF) were collected using blunted capillary tubes and were periodically assayed for penicillin by an agar‐well‐diffusion technique. Linear regression lines were constructed for concentration of penicillin‐time profiles. Similarity of the regression slopes for each treatment enabled the construction of three common lines by the method of co‐variance analysis in order to represent each treatment. Treatments were thereafter compared by the slopes of the common regression lines. A subconjunctival injection of procaine penicillin at a dose of 6 ×105iu in 2 ml, administered either through the skin or through the conjunctiva, produced a peak penicillin concentration in the CF of approximately 8 iu/ml for either route and a duration of therapeutic concentration (DTC) of 67.6± 4.9 and 40± 2.7 h respectively. A dose of 3± 105iu in 1 ml, administered through the conjunctiva, produced a similar peak but the DTC was reduced to 35± 4.2 h. The results of this study support field practices, as adequate penicillin concentrations were maintained by both techniques

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00637.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Sodium benzyl penicillin, procaine penicillin and benethamine penicillin were applied into the bovine conjunctival sac as an aqueous solution or in ointment form in order to study the concentration‐time profiles. The series of treatments was repeated in five animals in a random sequence. Penicillin concentration in conjunctival sac fluid (CF) was determined using the agar‐well‐diffusion assay technique. The data obtained were transformed to linear regression slopes. Similarity of the slopes within treatments (in five different eyes) enabled the construction of four common lines by co‐variance analysis to^represent each treatment. The regression coefficients of the four common lines were then compared to study the difference between treatments. Topical application of 5,000 iu sodium benzylpenicillin in aqueous solution at a concentration isotonic with 0.9% saline, produced a duration of therapeutic concentration (DTC) in CF of 12.6 ± 1.5 h. When the same salt or other less water‐soluble ones were formulated at the same concentration in an ointment base, the DTC was significantly prolonged. For all treatments, peak concentrations in CF were recorded at the first sampling and ranged between 7 iu/ml and 14 iu/ml. Sodium benzylpenicillin or procaine penicillin, both in the ointment base, produced DTCs of 38.8 ± 2.1 h and 37 ± 4.0 h, respectively, while the ointment formulation of benethamine penicillin produced a DTC of 56 ± 4.5 h. The prolonged duration observed in the eye ointments can be partly accounted for by the viscous nature of the base. Other differences may be dependent on relative water solubility of each penicillin product and complexity of the surface mucos

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00638.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Drug concentrations in serum, synovial fluid and tissue cage fluid (TCF) in calves were measured after single i.m. doses of oxytetracycline hydrochloride (OTC), procaine penicillin G (PPG) and potassium penicillin G (KPG) and single i.v. doses of sulphadimidine (SDM) and OTC. For all drugs, concentration—time curves in serum and synovial fluid were not identical but they had similar profiles, with peak levels occurring at about the same time. Concurrent concentrations were lower in synovial fluid than in serum. For each drug, elimination half‐lives from synovial fluid and from serum were similar, except for penicillin G after KPG administration which had a significantly longer half‐life from synovial fluid than from serum (P<0.05). Of the two penicillin G preparations, PPG gave a signficantly higher synovial fluidrserum area under curve (AUC) ratio than did KPG; 0.76 ± 0.10 and 0.54 ±0.12, respectively (P0.05). Potassium penicillin G (KPG), however, gave a significantly higher TCF:serum Af/C‐ratio than PPG; 0.55 ± 0.21 and 0.19 ± 0.07, respectively (P<0.05). It is concluded that serum concentrations of these antibacterial drugs give an approximate indication of levels in synovial fluid, whereas concentrations in TCF are considerably lower, with a slow rise and decline characteristic

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00639.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The pharmacokinetics of ronidazole and the bioavailability of a prolonged release tablet were studied in the homing pigeon. After intravenous administration of 5 mg ronidazole, the drug plasma concentration profile fitted a one‐compartment open model. The mean half‐life of the drug was 11 h and the volume of distribution was 0.86 I/kg. Total body clearance was 0.056 I/h/kg. A sustained release matrix tablet exhibited prolonged drug releasein vitro.After oral administration of the matrix tablet to pigeons drug absorption was nearly complete. When given on an empty stomach, the tablet failed as a prolonged release system. Administration to previously fed pigeons resulted in an increase intpmAXand a decrease inCp

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00640.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The pharmacokinetic analysis of plasma concentration‐time curves after a single i.v. dose of 20 mg/kg sulphatroxazole (STZ) to calves and cows revealed a small distribution volume of STZ (mean VD(area)= 0.22–0.26 1/kg) and an age dependent elimination (meant1/26.6–18.8 h). In calves and cows, STZ was extensively metabolized into theN4‐acetyl and 5‐hydroxy derivatives. In the plasma of calves, the N4‐acetyl metabolite (N4‐STZ) was present in greater amounts than the hydroxy metabolite (5‐OH‐STZ), while in cows' plasma concentrations of these two metabolites were similar. In the milk of dairy cows STZ concentrations paralleled those of the metabolites and were approximately 21 times lower than corresponding plasma concentrations. The mean plasma protein binding of STZ and its metabolites ranged from 36.4 to 82.5% of total concentration. The N4‐STZ derivative was excreted by tubular secretion; the 5‐OH‐STZ and the parent compound, mainly by glomerular filtration. In calves the majority of STZ administered was excreted as N4‐STZ (40–52%), while in cows the parent drug dominated

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00641.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

The purpose of this study was to investigate the effects of some a and β sympathomimetic and sympatholytic drugs on respiratory impedance in healthy conscious calves. Ten Friesian calves were investigated in this study. The forced oscillation technique was used to measure the resistance (Rrs) and the reactance (Xrs) of the respiratory system at frequencies ranging from 4 to 26 Hz. Isoprenaline (1 μg/kg i.v.), propranolol (3 μg/kg i.v.), noradrenaline (2 μg/kg i.v.), xylazine (20 μg/kg i.v.) and yohimbine (0.25 mg/kg i.v.) were administered. Isoprenaline induced a significant decrease ofRrs. An increase ofRrsafter administration of propranolol was observed but without any change of the frequency dependence ofRrs. A small increase in the resonant frequency was also recorded. A decrease ofRrswas recorded after yohimbine injection. Noradrenaline and xylazine administration increased the resistances and the resonant frequency and induced a negative frequency dependence ofRrs. These results suggest that (1) the major effects of β adrenergic drugs are on the central airways, (2) the a adrenergic system may play a role on the regulation of bronchomotor tone in calves, (3) the effects of a adrenergic drugs are on both central and peripheral airways and (4) the forced oscillation technique allows the differentiation of calibre changes occurring in small and large ai

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1989.tb00642.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY