Effect of sub-anesthetic xylazine and ketamine ('ketamine stun') administered to calves immediately prior to castration.
Vet Anaesth Analg
; 37(6): 566-78, 2010 Nov.
Article
em En
| MEDLINE
| ID: mdl-21040381
ABSTRACT
OBJECTIVE:
To describe the pharmacokinetics, cortisol response and behavioral changes associated with administration of sub-anesthetic xylazine and ketamine prior to castration. STUDYDESIGN:
Prospective, randomized experiment. ANIMALS Twenty-two male beef calves (260-310 kg).METHODS:
Calves were randomly assigned to receive the following treatment immediately prior to surgical or simulated castration; 1) uncastrated, placebo-treated control (CONT) (n=4),2) Castrated, placebo treated control (CAST) (n=6), 3) castrated with intravenous xylazine (X) (0.05 mg kg(-1)) (n=6), and 4) castrated with IV xylazine (X) (0.05 mg kg(-1) ) combined with ketamine (K) (0.1 mg kg(-1)) (n=6). Blood samples collected over 10 hours post-castration were analyzed by LC-MS-MS for drug concentrations and chemiluminescent immunoassay for cortisol determination.RESULTS:
Drug concentrations during the first 60 minutes post-castration fit a one-compartment open model with first-order elimination. The harmonic mean elimination half-lives (± pseudo SD) for X, X with K and K were 12.9 ± 1.2, 11.2 ± 3.1 and 10.6 ± 2.8 minutes, respectively. The proportion of the total area under the effect curve (AUEC) for cortisol during this period was significantly lower in the X group (13 ± 3%; p=0.006) and the X+K group (14 ± 2%; p=0.016) compared with the CAST calves (21 ± 2%). However, after 300 minutes the AUEC in the X group was higher than CAST. Significantly more calves demonstrated attitude that was unchanged from pre-manipulation behavior in the CONT (p=0.021) and X+K treated calves (p=0.0051) compared with the CAST calves.CONCLUSIONS:
Behavioral changes and lower serum cortisol concentrations during the first 60 minutes post-castration were associated with quantifiable xylazine and ketamine concentrations. CLINICAL RELEVANCE Low doses of xylazine and ketamine administered immediately prior to castration may offer a safe, efficacious and cost-effective systemically administered alternative or adjunct to local anesthesia.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Xilazina
/
Orquiectomia
/
Ketamina
/
Anestesia Intravenosa
Limite:
Animals
Idioma:
En
Revista:
Vet Anaesth Analg
Assunto da revista:
ANESTESIOLOGIA
/
MEDICINA VETERINARIA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos