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1.
25 horses which entered the clinic for minor surgery, received ketamine (2.2 mg/kg i.v.) for induction of anesthesia after previous sedation with xylazine (1.1 mg/kg i.v.). As soon as the horses were in the lateral recumbency, the benzodiazepine derivate climazolam was administered at a dose of 0.1 mg/kg i.v. (10 horses) or 0.2 mg/kg i.v. (15 horses). The anesthesia was maintained with repeated injections of ketamine (1.1 mg/kg i.v. every 9-12 minutes). At the end of the surgery, 20 minutes after the last ketamine injection, Ro 15-3505, a benzodiazepine antagonist, was injected at a dose of 0.01 mg/kg i.v. or 0.02 mg/kg i.v. Climazolam successfully suppressed the adverse reactions of ketamine, such as poor muscle relaxation, hyperacusis and convulsions. The benzodiazepine antagonist Ro 15-3505 allowed good control of the duration of anesthesia and--in most cases--a smooth, predictable recovery period was the result.  相似文献   

2.
5 adult dwarf goats were injected intravenously with diazepam, chlorpromazine or isotonic saline. Both diazepam at 0.04 mg/kg and chlorpromazine at 0.5 mg/kg significantly stimulated food intake above the control 0.9% NaCl levels. The stimulatory effect appears to be most pronounced within the first 15 min post injection, and was no longer evident between 30 and 45 min after the bolus injection of the tranquillizers.  相似文献   

3.
5 adult dwarf goats were injected intravenously with diazepam, chlorpromazine or isotonic saline. Both diazepam at 0.04 mg/kg and chlorpromazine at 0.5 mg/kg significantly stimulated food intake above the control 0.9% NaCl levels. The stimulatory effect appears to be most pronounced within the first 15 min post injection, and was no longer evident between 30 and 45 min after the bolus injection of the tranquillizers.  相似文献   

4.
Summary

The most common sign of febrile diseases is anorexia, which develops at a time when adequate caloric and micronutrient availability may be critical. In order to study the relationship of fever and anorexia, feed intake in dwarf goats was studied under conditions of fever and antipyresis. Furthermore, experiments were done to establish whether a feed intake stimulant would override the anorexia during febrile conditions. Infection with Ehrlichia phagocytophila and i.v. injection of Escherichia coli endotoxin (0111B4, 0.1 μg/kg body weight) both resulted in increased rectal temperatures and significant reductions in feed intake. Administration of the antipyretic drug flurbiprofen (1 mg/kg) to febrile animals inhibited the temperature responses, but food intake was still suppressed. Diazepam (0.06 mg/kg), a feed intake stimulant, did not override the anorexia associated with fever. Blocking the febrile response of E. coli LPS‐injected goats with flurbiprofen plus diazepam or with flurbiprofen plus naloxone (0.1 mg/kg) did not antagonise their reduced feed intake either.

The effects of these drugs and of endotoxin on rumen motility adds an interesting aspect to their activities in the CNS, since the CNS has been shown to regulate various aspects of forestomach motility, which in turn could alter feeding behaviour. Moreover, our findings are consistent with the hypothesis that the suppression of feed intake might depend on the release of interleukin‐1.  相似文献   

5.
The most common sign of febrile diseases is anorexia, which develops at a time when adequate caloric and micronutrient availability may be critical. In order to study the relationship of fever and anorexia, feed intake in dwarf goats was studied under conditions of fever and antipyresis. Furthermore, experiments were done to establish whether a feed intake stimulant would override the anorexia during febrile conditions. Infection with Ehrlichia phagocytophila and i.v. injection of Escherichia coli endotoxin (0(111) B4, 0.1 microgram/kg body weight) both resulted in increased rectal temperatures and significant reductions in feed intake. Administration of the antipyretic drug flurbiprofen (1 mg/kg) to febrile animals inhibited the temperature responses, but food intake was still suppressed. Diazepam (0.06 mg/kg), a feed intake stimulant, did not override the anorexia associated with fever. Blocking the febrile response of E. coli LPS-injected goats with flurbiprofen plus diazepam or with flurbiprofen plus naloxone (0.1 mg/kg) did not antagonise their reduced feed intake either. The effects of these drugs and of endotoxin on rumen motility adds an interesting aspect to their activities in the CNS, since the CNS has been shown to regulate various aspects of forestomach motility, which in turn could alter feeding behaviour. Moreover, our findings are consistent with the hypothesis that the suppression of feed intake might depend on the release of interleukin-1.  相似文献   

6.
Safe, effective, and reversible immobilization protocols are essential for the management of free-ranging red wolves (Canis rufus). Combinations using an alpha2-adrenoceptor agonist and ketamine have been shown to be effective for immobilization but are not reversible and can produce severe hypertension and prolonged or rough recoveries. To minimize hypertension and provide reversibility, 24 red wolves were immobilized using three medetomidine-butorphanol (MB) combinations without the use of ketamine in the initial injection. All wolves were administered medetomidine (0.04 mg/kg i.m.) and butorphanol (0.4 mg/kg i.m.). Seven wolves received no other immobilization agents (MB wolves), nine received diazepam (0.2 mg/kg i.v.) at the time they were instrumented (MBD wolves), and eight received ketamine (1 mg/kg i.v.) 30 min after instrumentation (MBK30 wolves). Physiologic parameters were monitored during immobilization. The heart rate was similar among the three groups for the first 30 min, and marked bradycardia was noted in one wolf from each group. Hypertension was observed initially in all three groups but was resolved within 10-30 min. The MBK30 wolves had significant elevations in heart rate and transient hypertension after intravenous ketamine administration. Most wolves had mild to moderate metabolic acidemia. Immobilizing drugs were antagonized in all wolves with atipamezole (0.2 mg/kg i.m.) and naloxone (0.02 mg/kg i.m.). The medetomidine-butorphanol-diazepam wolves were also given flumazenil (0.04 mg/kg i.v.). All wolves were standing within 12 min and were fully recovered within 17 min. Medetomamine-butorphanol and MBD combinations provided effective and reversible immobilization of red wolves without the sustained hypertension associated with the use of alpha2-adrenoceptor agonist-ketamine combinations. Delaying the administration of ketamine reduced its hypertensive effects.  相似文献   

7.
We studied four different drug regimes for anaesthetic management in chinchillas and evaluated and compared their cardiovascular and respiratory effects. In this randomized, cross-over experimental study, seven adult chinchillas, five females, two males [515 +/- 70 (SD) g] were randomly assigned to one of the following groups: group 1 [midazolam, medetomidine and fentanyl (MMF), flumazenil, atipamezole and naloxone (FAN); MMF-FAN] received 1.0 mg/kg midazolam, 0.05 mg/kg medetomidine and 0.02 mg/kg fentanyl i.m., and for reversal 0.1 mg/kg flumazenil, 0.5 mg/kg atipamezole and 0.05 mg/kg naloxone s.c. after 45 min; group 2 (MMF) 1.0 mg/kg midazolam, 0.05 mg/kg medetomidine and 0.02 mg/kg fentanyl i.m.; group 3 [xylazine/ketamine (X/K)] 2.0 mg/kg xylazine and 40.0 mg/kg ketamine i.m.; and group 4 [medetomidine/ketamine (M/K)] 0.06 mg/kg medetomidine and 5.0 mg/kg ketamine i.m. Reflexes were judged to determine anaesthetic stages and planes. Anaesthesia with X/K and M/K was associated with a prolonged surgical tolerance and recovery period. By reversing MMF, recovery period was significantly shortened (5 +/- 1.3 min versus 40 +/- 10.3 min in MMF without FAN, 73 +/- 15.0 min in X/K, and 31 +/- 8.5 min in M/K). Without reversal, MMF produced anaesthesia lasting 109 +/- 16.3 min. All combinations decreased respiratory and heart rate but compared with X/K and M/K, respiratory and cardiovascular complications were less in the MMF groups. Focussing on the clinical relevance of the tested combinations, completely reversible anaesthesia showed two major advantages: anaesthesia can be antagonized in case of emergency and routinely shortens recovery. In small animals particularly these advantages lead to less complications and discomfort and thus often can be lifesaving. As all analgesic components (medetomidine and fentanyl) are reversed, postoperative analgesia should be provided before reversal of anaesthesia.  相似文献   

8.
Evaluation of Three Midazolam-Xylazine Mixtures Preliminary Trials in Dogs   总被引:1,自引:0,他引:1  
The depressant effects of midazolam and xylazine on the central nervous system (CNS) were evaluated in 12 dogs. Xylazine was administered to six dogs (1.1 mg/kg intravenously [IV]) followed in 5 minutes by midazolam (1.0 mg/kg intramuscularly [IM]). In a second group of six dogs, xylazine (2.2 mg/kg IM) was followed in 5 minutes by midazolam (1.0 mg/kg IV). Both drug regimens induced rapid and profound sedation or anesthesia. Duration of action varied with the doses and routes of administration. Dogs given the high dose of xylazine IM had an arousal time of 95.4 +/- 8.9 minutes and a walking time of 155.4 +/- 8.8 minutes. These values exceeded the IV xylazine values threefold. Partial reversal of CNS depression was accomplished with either a benzodiazepine antagonist (flumazenil) or an alpha-2 antagonist (yohimbine). In a separate trial, a mixture of xylazine (0.55 mg/kg), midazolam (1.0 mg/kg), and butorphanol (0.1 mg/kg) with and without glycopyrrolate was evaluated in eight dogs. As with the xylazine-midazolam combinations, the CNS depressant effect of this mixture was clinically indistinguishable from anesthesia achieved with other rapid-acting injectable agents. Clinical signs of CNS depression were readily and completely antagonized by the simultaneous injection of flumazenil and yohimbine.  相似文献   

9.
The cardiovascular effects of xylazine and atropine, separately and in combination, were studied in goats. Methylatropine was used to distinguish between the central and peripheral effects of atropine. Mean arterial blood pressure and heart rate were recorded, and the sedative effect and changes in respiration and salivation noted. Intravenous infusion of xylazine (2.4-80.0 micrograms/kg) decreased mean arterial blood pressure and heart rate in a dose-dependent manner. Single intravenous injections of both atropine sulphate (0.1 mg/kg) and methylatropine bromide (0.05 mg/kg) increased blood pressure and heart rate. After methylatropine, tachycardia lasted twice as long as after atropine. Following atropinization, a potentiated rise in mean arterial blood pressure was present during the infusion of xylazine (80 micrograms/kg). Xylazine-induced bradycardia was reversed by both atropine and methylatropine. The action of atropine is presumed to be primarily peripheral because of the similar effects with methylatropine. Xylazine-induced sedation was dose dependent. At the highest dose the goats were unable to stand for 30-60 min, respiration became irregular with periods of apnoea, and saliva started to drip a few minutes after infusion without increased salivation. Atropine had no visible effect on the sedation, pattern of respiration or saliva dripping effect of xylazine.  相似文献   

10.
The biodegradation of chloramphenicol was studied by incubating the drug (at concentrations of 72, 48 and 24 micrograms/ml) with ruminal fluid samples from dwarf goats fed two different diets. Biodegradation of the drug was much faster in samples from animals which were fed with hay and concentrate than in those obtained from goats which were fed grass pellets only. Recently, it has been suggested that lysine-vasopressin injected intravenously induces closure of the oesophageal groove in cattle and goats. Therefore, the influence of lysine-vasopressin on the oral absorption of chloramphenicol (50 mg/kg body wt) was studied in dwarf goats, using two formulations of chloramphenicol. The results suggest that vasopressin failed to induce this reflex mechanism. Furthermore, the shapes of the plasma concentration-time curves after oral administration of chloramphenicol palmitate and chloramphenicol dissolved in propylene glycol were markedly different. Possible mechanisms for the observed differences are discussed.  相似文献   

11.
Two adult California sea lions (Zalophus californianus) were effectively anesthetized 13 times with medetomidine (0.010-0.013 mg/kg), midazolam (0.2-0.26 mg/kg), and butorphanol (0.2-0.4 mg/kg) by i.m. hand or pole syringe injection. For each anesthetic event, atropine (0.02 mg/kg, i.m.) was administered 6-20 min after initial injections, and oxygen administration via face mask or nasal insufflation began at the same time. Light anesthesia was induced in 8-22 min and lasted 13-78 min. During eight of the procedures, isoflurane (0.5-2.0%) was administered via face mask or endotracheal tube for an additional 30-120 min to facilitate longer procedures or surgery. Anesthesia was antagonized with atipamezole (0.05-0.06 mg/kg) and naltrexone (0.1 mg/kg) in seven events, with the addition of flumazenil (0.0002-0.002 mg/kg) in six events. The antagonists were administered by i.m. injection 42-149 min after administration of the induction agents. All sea lions recovered to mild sedation within 4-17 min after administration of the antagonists.  相似文献   

12.
Kaya, F., Van Duin, C.T.M. & Van Miert, A.S.J.P.A.M. Food intake and rumen motility in dwarf goats. Effects of some dopamine receptor agonists. J. vet. PharmacolTherap, 17 , 120–126. In ruminants, the dopaminergic regulation of feeding behaviour has not been investigated. Therefore, the effects of dopamine receptor agonists and antagonists on food intake and forestomach motility were studied in dwarf goats Goats treated i.v. with bromocriptine (1 μg or 2.5 μg/kg body wt/min during 10 min) ate less food than when treated with saline. This inhibitory effect on food intake could not be prevented by the peripheral dopamine receptor antagonist domperidone (0.5 mg/kg body wt i.v.). In contrast, dopamine (i.v. 20 μg/kg body wt/min during 15 min), levodopa (i.v. 40 μg/kg body weight during 10 min), apomorphine (i.v. 2 μg/kg body wt/min during 10 min) and lisuride (i.v. 0.2 μg/kg body wt/min during 15 min and 0.5 μg/kg body wt during 10 min) failed to modify food intake. Given in association with benserazide, a decarboxylase inhibitor (i.v. 20 μg/kg body wt/min during 10 min), levodopa was still inactive as an anorectie agent. Levopoda, bromocriptine and lisuride administered at similar dose rates to those which were used in the food intake experiments, induced some clinical signs including inhibition of forestomach contractions. The inhibition of rumen contractions induced by these drugs was completely antagonized by domperidone pretreatment. These results, together with earlier in vivo and in vitro observations, suggest that the inhibitory effects of dopamine receptor agonists on forestomach contractions are due to interactions with peripheral dopaminergic receptors. The change in smooth muscle tension, which leads to a change in the signals transmitted via vagal afferents to the central nervous system, probably does not modify feeding behaviour in dwarf goats. Furthermore, i.v. infusion of lisuride induced rumination when the inhibition of the forestomach contractions was prevented by domperidone; this effect may involve α2-adrenoceptor activation.  相似文献   

13.
Participation of tryptaminergic receptors in the control of forestomach motility was investigated in conscious sheep using strain-gauges and chronically implanted electrodes. Two hours after feeding the sheep, serotonin (5-HT) was infused into the jugular vein (i.v.), or the carotid artery (i.c.), or into the lateral cerebral ventricles (i.c.v.), over a 10-min period. An i.v. dose of 16 micrograms/kg/min abolished the cyclic propagated contractions throughout the forestomach, increased ruminoreticular tone, and induced simultaneous contractions of all the parts of the rumen. A dose of 1.6 micrograms/kg/min i.c. or i.v. 5-HT inhibited phasic contractions. The effects of 5-HT were blocked completely by i.c.v. administration of methysergide (20 micrograms/kg) and imipramine (200 micrograms/kg), and blocked partially by naloxone (25 micrograms/kg), but unaffected by atropine (50 micrograms/kg). The inhibitory effects of i.v. 5-HT were antagonized by methysergide (200 micrograms/kg, i.v.) but unaffected by imipramine (2 mg/kg, i.v.) and atropine (250 micrograms/kg, i.v.). Only the i.v. administration of methysergide blocked the inhibition induced by i.c. infusion (1.6 micrograms/kg/min) of 5-HT. It is suggested that 5-HT exhibits an inhibitory control on forestomach phasic contractions through hypothalamic and bulbar 5-HT receptors, and exerts peripheral excitatory effects on the tone of the rumen wall.  相似文献   

14.
The influence of triiodothyronine (5 micrograms/kg of body weight, sc, q 12 h for 7 days) on antipyrine (AP, 25 mg/kg, IV) plasma elimination and urinary metabolite excretion was studied in castrated male dwarf goats. After triiodothyronine treatment, a significant increase in AP elimination was found. However, the observed changes in clearances for production of AP metabolites (nor-AP, 3-hydroxymethyl-AP; 4-hydroxy-AP, and 4,4'-dihydroxy-AP) do not suggest a clear selectivity of triiodothyronine toward any of the metabolic pathways of AP.  相似文献   

15.
The purpose of this study was to evaluate the effects on the intraocular pressure (IOP) of lidocaine or diazepam administered intravenously (IV) before induction of anesthesia with propofol-atracurium and orotracheal intubation in normal dogs, as well as the effects on the IOP of lidocaine applied topically to the larynx after induction with propofol-atracurium. We randomly assigned 32 random-source dogs, obtained from municipal pounds, to receive the following: lidocaine, 2 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (LIDOsal); saline, 0.1 mL/kg IV, with lidocaine, 2 mg/kg topically applied to the larynx (SALlido); diazepam (Valium), 0.25 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (VALsal); or saline, 0.1 mL/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (SALsal). We measured arterial pressure directly, by means of an indwelling catheter placed in a peripheral artery. Anesthesia was induced with propofol, 8 mg/kg IV, until loss of jaw tone, followed by atracurium, 0.3 mg/kg IV. We measured the IOP in triplicate in each eye before premedication, before induction, before intubation, and after intubation. After induction, the IOP was significantly increased except in the VALsal group, in which the IOP was significantly lower than in the negative-control group before intubation. After intubation, the IOP was significantly elevated in all the groups compared with the values before induction. Cardiovascular parameters were essentially similar in all the groups, except for a significant increase in blood pressure after intubation in the SALlido group. Thus, propofol-atracurium anesthesia causes an increase in IOP that is blunted by diazepam. However, diazepam does not blunt the increase in IOP observed with intubation.  相似文献   

16.
The objective of the study was to determine the analgesic and systemic effects of subarachnoid administration of xylazine hydrochloride (XY), lidocaine hydrochloride (LI) and their combination (XYLI) in goats. Six healthy goats were used in a prospective randomised study. Three treatments were administered to each goat, with 1-week intervals between each treatment. Treatments consisted of 0.1 mg/kg xylazine, 2.5 mg/kg lidocaine and a combination of xylazine 0.05 (mg/kg) and lidocaine (1.25 mg/kg). Analgesia, ataxic, sedative, cardiovascular and respiratory effects, and rectal temperature were evaluated before (baseline) and at 5, 10, 15, and 30 min after subarachnoid injection, and then at 30-min intervals until loss of analgesia occurred. Lidocaine induced analgesia in 3.1 +/- 1 min (mean +/- SD), which lasted for 66 +/- 31 min. Heart and respiratory rates and blood pressure remained unchanged after lidocaine-induced analgesia. Xylazine induced analgesia in 9.5 +/- 2.6 min and xylazine-lidocaine in 3.2 +/- 1.2 min. Xylazine-lidocaine-induced analgesia lasted longer (178.3 +/- 37 min) than that induced by xylazine (88.3 +/- 15 min). The XYLI treatment induced prolonged motor blocking (115 min), more than the XY (80 min) and LI (90 min) treatments. Both xylazine and xylazine-lidocaine caused significant decreases in the heart and respiratory rates, but not in blood pressure. The combination of xylazine (0.05 mg/kg) and lidocaine (1.25 mg/kg) can be administered subarachnoidally (between last lumbar vertebra and 1st sacral vertebra) to produce prolonged (> 2.5 h) analgesia of the tail, perineum, hind limbs, flanks and caudodorsal rib areas in goats. Despite the prolonged analgesia, using this combination is desirable for relieving postoperative pain, but it may be a disadvantage due to a motor block when dealing with goats.  相似文献   

17.
Between 1987 and 1997, we chemically immobilized 597 wild sea otters (Enhydra lutris) in Alaska for the collection of biological samples or for surgical instrumentation. One drug-related sea otter fatality occurred during this time. Fentanyl in combination with diazepam produced consistent, smooth inductions with minimal need for supplemental anesthetics during procedures lasting 30-40 min. Antagonism with naltrexone or naloxone was rapid and complete, although we observed narcotic recycling in sea otters treated with naloxone. For surgical procedures, we recommend a fentanyl target dose of 0.33 mg/kg of body mass and diazepam at 0.11 mg/kg. For nonsurgical biological sample collection procedures, we recommend fentanyl at 0.22 mg/kg and diazepam at 0.07 mg/kg. We advise the use of the opioid antagonist naltrexone at a ratio of 2:1 to the total fentanyl administered during processing.  相似文献   

18.
Quantitative EEG was assessed in six dogs anaesthetized with 1.8% end-tidal isoflurane concentration and following diazepam (0.2 mg/kg i.v.) administration. Ventilation was controlled to maintain normocapnia. Five dogs were subsequently given the benzodiazepine antagonist, flumazenil (0.04 mg/kg i.v.), and quantitative EEG was recorded. One dog received a saline injection following diazepam (as a control) and quantitative EEG was recorded for an additional 2.5 h. Heart rate, arterial blood pressure, esophageal temperature, arterial pH and blood gas tensions, end-tidal CO2 tension and end-tidal isoflurane concentration were monitored throughout the study. A 21 lead linked-ear montage was used for recording EEG. Quantitative EEG data were stored on an optical disc for analysis at a later date. Values for absolute power of EEG were determined for theta, delta, alpha, and beta frequencies. Cardiovascular parameters remained stable throughout the study. Diazepam administration was associated with decreased absolute power in all frequencies of EEG at all electrode sites. The duration of diazepam-induced decreased absolute power of EEG was at least 3 h in one dog. Administration of flumazenil antagonized diazepam-induced decreased absolute power of EEG in all frequencies at all electrode sites. We conclude that quantitative EEG provides a relatively non-invasive, objective measure of diazepam- and flumazenil-induced changes in cortical activity during isoflurane anaesthesia.  相似文献   

19.
This study was designed to evaluate 2 combinations for immobilization of bison. Seven wood bison received 1.5 mg/kg body weight (BW) of xylazine HCl + 1.5 mg/kg BW of zolazepam HCl and 1.5 mg/kg BW of tiletamine HCl on one occasion. The bison received 60 micrograms/kg BW of medetomidine HCl + 0.6 mg/kg BW of zolazepam HCl and 0.6 mg/kg BW of tiletamine HCL on another occasion. Xylazine was antagonized with 3 mg/kg BW of tolazoline HCl and medetomidine HCl was antagonized with 180 micrograms/kg (BW) of atipamezole HCl. Temporal characteristics of immobilization and physiological effects (acid-base status, thermoregulatory, cardiovascular, and respiratory effects) of the drug combinations were compared. Induction was significantly faster with xylazine HCl-zolazepam HCl/tiletamine HCl. Recovery following antagonist administration was significantly faster with medetomidine HCl-zolazepam HCl/tiletamine HCl. The average drug volumes required were 7.00 mL of xylazine HCl-zolazepam HCl/tiletamine HCL and 2.78 mL of medetomidine HCl-zolazepam HCl/tiletamine HCl. Hypoxemia, hypercarbia, and rumenal tympany were the major adverse effects with both drug combinations.  相似文献   

20.
The present report describes a comparative study in dwarf goats on human IFN-alpha 2a (0.5 x 10(6) IU kg-1 body weight IM), poly I: poly C (an interferon inducer; 30 micrograms kg-1 b.w. IV), and Escherichia coli endotoxin (an I1-1 inducer; 0.1 micrograms kg-1 b.w. IV). Although IFNs are considered to be species specific, human IFN-alpha 2a was very potent in dwarf goats. All 3 stimuli induced the 'acute phase response'. Among the varied physiological alterations, which together produce this response, are fever and depression, inhibition of gastric function, tachycardia, a decrease in serum alkaline phosphatase activity, leukopenia, lymphopenia and neutropenia followed by neutrophilic leukocytosis, hypoferraemia and hypozincaemia. The results suggest that, apart from I1-1, IFN-alpha also seems to mediate the systemic 'acute phase response' to certain exogenous stimuli.  相似文献   

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