ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00813.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The central arterial pharmacokinetics of thiopental were studied in six rabbits, six sheep and six dogs after a short infusion at approximately 10 mg/kg min. Thiopental was infused to a defined electro‐encephalographic endpoint (EEG burst suppression). The time to reach early burst suppression was longer in the dog (3.9 ± 0.5 min) compared with the sheep (3.0 ± 0.6 min) and the rabbit (2.5 ± 0.5 min). The total dose required to produce the same level of EEG activity was higher in the dog (35.9 ± 6.8 mg/kg) compared with the sheep (24.3 ± 5.3 mg/kg) and the rabbit (21.6 ± 6.8 mg/kg). The plasma concentration‐time data for each animal was fitted using non‐linear regression to a bior tri‐exponential function. In all animals, the plasma‐time profile was best described as a tri‐exponential decay. The initial volume of distribution was similar in all three species (rabbit, 38.6 ± 10.0 mg/kg; sheep, 44.5 ± 9.1 ml/kg; dog, 38.1 ± 18.4 ml/kg). The maximum arterial plasma thiopental concentration achieved at EEG burst suppression was higher in the sheep (221.8 ± 27.9 μg/ml) than the dog (164.7 ± 29.9 μg/ml) or the rabbit (112.3 ± 15.1 μg/ml). Thiopental distribution clearance was slower in the sheep (43.6 ± 15.1 ml/min kg) compared with the rabbit (110.5 ± 18.7 ml/min kg) and the dog (97.2 ± 47.2 ml/min kg). Elimination half‐life was extended in the sheep (251.9 ± 107.8 min) and dog (182.4 ± 57.9 min) relative to the rabbit (43.1 ± 3.4 min). The rapid half‐life in the rabbit resulted from a large elimination clearance (14.6 ± 6.8 ml/min kg) and a small steady‐state volume of distribution (648.1 ± 180.5 ml/kg). Relative to the rabbit, the other species had large steady‐state volumes of distribution (dog, 815.8 ± 119.0 ml/kg; sheep, 947.3 ± 141.2 ml/kg), and small elimination clearances (dog, 3.4 ± 1.0 ml/min kg; sheep, 3.0 ± 0.9 ml/min kg). The initial disposition kinetics of thiopental in the sheep and dog were similar; however, the sheep tended to demonstrate a slower distribution clearance. The rapid and extended fall in arterial thiopental concentrations following administration in the rabbit may cause a short period of anesthesia and rapid recovery in that species. Additionally, the rabbit may require lower arterial concentrations to achieve EEG silence. The rabbit brain may be intrinsically more sensitive to barbiturates or thiopental may be capable of equilibrating with rabbit bra

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00814.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

A comparison of the analgesic potency of the α2‐adrenoceptor agonist, xylazine, in control healthy sheep and sheep suffering chronic pain from footrot, indicated that the analgesic effectiveness of xylazine was significantly reduced in the animals experiencing chronic pain. This was measured by recording the threshold to a mechanically applied pressure stimulus. Furthermore, when the condition was apparently resolved, by conventional treatment over a period of 2 to 3 weeks, the decreased analgesic effectiveness of the α2‐agonist was still apparent although the animals were clinically cured of the fo

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00815.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

A high‐performance liquid chromatographic method to measure urinary indomethacin levels is described. In 0.5 ml urine, 1 μg/ml of indomethacin could be detected. Alkaline hydrolysis of urine resulted in the decomposition of indomethacin. When two suppositories of Indocidr̀ corresponding to 200 mg indomethacin were administered rectally to four horses the drug was rapidly absorbed and remained detectable in urine from 1 to 12 h. The excretion rate peaked after 2‐3 h while the maximal concentration ranged from 18.5 to 80.6 μg/ml. Only 8 to 16% of the indomethacin dose was eliminated in urine after 12 h. A fraction of the dose was excreted as the glucuronide con

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00816.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Compliance with Norwegian legal regulations for veterinary prescriptions was investigated and evaluated. The study was designed as a cross‐sectional prescription survey, and the prescriptions were recorded in Dbase III. Of the 6505 written and telephone prescriptions collected only about one in five fulfilled the legal requirements, namely, giving information about the animal species the drug was intended for, indication for the prescribed drug and directions for use. On average 86% contained information about the animal species, while 26% and 80%, respectively, contained information about the indication for the prescribed drug and directions for use. The number of prescriptions on which indication and directions for use were given, was significantly higher for written prescriptions than for telephone prescriptions, and for prescriptions of human preparations compared with prescriptions of veterinary preparations. For pets, the number of prescriptions containing directions for use was significantly higher than for production animals. The proportion of prescriptions for pets giving a statement of the indication was not significantly different from prescriptions for production animal

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00817.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Experiments to characterize the effects of two immunomodulators, namely, isoprinosine and levamisole, on factors relevant to the resistance of calves to respiratory infection were undertaken. Daily oral doses of isoprinosine decreased the influx of neutrophils into the respiratory tract, increased membrane immunoglobulin and complement receptor expression on cells from bronchoalveolar lavage samples and decreased the severity of respiratory disease. Additional intravenous doses produced similar effects on neutrophil migration to the respiratory tract and on membrane receptor expression, but the changes were no greater than those seen with oral isoprinosine alone. No significant changes in the anti‐bacterial activity of cells in bronchoalveolar lavage samples followed isoprinosine treatment.In vitroincubation of pulmonary alveolar macrophages harvested from normal calves with isoprinosine increased their expression of immunoglobulin and complement receptors. Levamisole did not affect neutrophil migration to the lower respiratory tract or membrane receptor expression by pulmonary alveolar macrophages afterin vivoorin vitrotreatment. The immunomodulatory effects of isoprinosine beneficially increase the resistance of calves to respiratory disease, and are potentially useful in the control of infectious diseases of farm animal

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00818.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The binding of nitroxynil to total plasma proteins of cows, sheep and rabbits was characterized using equilibrium dialysis. The data indicate clearly that nitroxynil was highly (97‐98%) bound to plasma protein of each animal. This linear binding would be due to the particular power exerted by serum albumin.The results are in good agreement with known pharmacokinetic properties of nitroxynil in domestic specie

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00819.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The effect of experimentalPasteurella haemolyticainfection on the intravenous and intramuscular pharmacokinetics of flumequine was studied in dairy calves. The plasma concentration‐time curve of flumequine after intravenous injection of 5 mg/kg bodyweight flumequine of a 10% solution before and after experimental infection, was best described by a three‐compartment open model. After intramuscular injection of the same dosage rate of a 3% flumequine suspension it was best described by the one‐compartment open model with first‐order absorption. The experimental infection by intratracheal administration of infectious bovine rhinotracheitis (IBR)‐virus and 5 days later intrapulmonary administration ofPasteurella Iraemolylicaproduced a clear temperature rise and signs of disease expressed as Average Health Status. Subsequently, plasma Fe and Zn concentration decreased after infection. The distribution volumes Vc, Vd(area) and Vd(ss)after infection (0.07± 0.04, 1.38 ± 0.36 and 0.50 ±0.11 1/kg, respectively) were smaller than those before infection, but the differences were not significant (P≤0.1). The intravenousAUC.was significantly increased (21.86 ± 3.51 to 33.85 ± 2.97 mg.h/I,P≤ 0.01) and the total body clearance (ClB) significantly decreased (0.24 ± 0.02 to 0.15 ± 0.01,P≤ 0.01) after infection. After intramuscular injection of flumequine at 5 mg/kg as a 3% suspension, only the bioavailability,F, was significantly decreased after infection (78.5 ± 14.3 to 59.7 ± 21.2%,P≤ 0.02). However, this had no consequences for the dosage regimen used. The urine concentration ratio flumequine:7‐hydroxy‐flumequinerconjugated flumequine changed from 2:1:10 before infection to 6:1:15 after infection, which indicates that hydroxylation and glucuronidation as metabolic pathways for flumequine were decreased

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00820.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

The agar dilution method was used to determine the bacteriostatic activity of 28 antimicrobial agents against 141 strains to the genusBacteroidesand 29 strains from the genusFusobacterium.All organisms were isolated from clinical cases of ovine footrot. The strains were isolated from 125 Merino sheep, over a period of 2 years, from January 1987 to December 1988. The three ureidopenicillins studied (azlocillin, mezlocillin and piperacillin) proved to be the most effective antimicrobial agents. Chloramphenicol, metronidazole and tinidazole effectively inhibited the growth ofBacteroidesspp., while phosphomycin was active againstFusobacteriumspp.

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00821.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY

摘要:

Two controlled studies to determine efficacy in the horse were performed with eltenac, a new injectable, non‐steroidal anti‐inflammatory drug (NSAID). Clinical trials were carried out with a dose rate of 1 mg/kg body weight in a randomized, placebo‐controlled, double‐blind design to assess therapeutic efficacy in acute inflammatory disorders and in animals with orthopaedic conditions. In a preliminary pharmacokinetic investigation in six horses mean elimination half‐life was 1.7 h after i.v. administration. In the first clinical study, analgesic activity on pain‐related lameness was determined in a total of 64 horses. Pain was assessed using a rating scale. Compared with the placebo treatment, eltenac produced significant pain relief after a single i.v. injection for a period of 24 h. In the second trial the anti‐oedematous effect was determined in post‐operative wound swelling following castration in two groups of 10 colts. After surgery, the horses received either an injection of 1 mg/kg eltenac or a placebo injection on three consecutive days. Swelling was assessed by measuring the diameter of the external preputial fold using two methods: callipers and a rating scale of 0 to 3. Additionally, photographs were taken on days 1, 2 and 4. Compared with the placebo treatment, eltenac inhibited pain and swelling significantly. The effect was maintained for up to 48 h after the

ISSN:0140-7783    

DOI:10.1111/j.1365-2885.1991.tb00822.x

出版商:Blackwell Publishing Ltd    

年代:1991

数据来源: WILEY