Cardiopulmonary effects of a xylazine and ketamine combination in pigs

The carotid and pulmonary arteries were catheterised in six pigs anaesthetised with thiopentone sodium and halothane. A minimum of five days was allowed to elapse before the investigation. The carotid artery pressure, pulmonary artery pressure, cardiac output, arterial pH, PO2, PCO2, plasma glucose and lactate were measured before and after intravenous injection of xylazine (1 mg kg-1) and ketamine 10 mg kg-1). Complete analgesia was produced for 10 minutes in all pigs but by 25 minutes all animals responded to a painful stimulus. The cardiac output and arterial PO2 were significantly decreased for 30 minutes and 10 minutes, respectively. The total vascular resistance was significantly increased. No statistically significant changes occurred in the other variables measured.     

Evaluation of a combination of xylazine, ketamine, and halothane for anesthesia in llamas

Anesthesia induced by use of a combination of xylazine, ketamine, and halothane, under conditions of spontaneous and mechanically controlled ventilation, was evaluated in 5 llamas positioned in dorsal recumbency. Using chronically implanted catheters, systemic arterial blood pressure, pulmonary arterial pressure, right atrial pressure, heart rate and rhythm, cardiac output, blood pH and gas tensions, body temperature, and respiratory rate were measured before anesthesia induction (baseline), throughout the anesthetic period, and for 1 hour into the recovery period. During anesthesia, llamas undergoing spontaneous ventilation developed hypercapnia and respiratory acidosis. Cardiovascular function was decreased during both types of ventilation. The combination of xylazine, ketamine, and halothane in various doses and 2 ventilation procedures (spontaneous and controlled) provided a reliable method for general anesthesia in llamas, but marked cardiovascular depression developed during anesthesia maintenance with halothane. Spontaneous ventilation resulted in potentially clinically important respiratory acidosis.     

Immobilization of cattle and bison with a combination of xylazine, zolazepam-tiletamine and ketamine

The aim of this study was to find a safe and reliable alternative to Immobilon for the immobilization of (feral) cattle. A combination of xylazine, zolazepam-tiletamine and ketamine was tested in Limousin cattle, Scottish Highland cattle, and American bison. Bodyweight, induction time, arterial O2 saturation and the total downtime were measured. Arterial blood was taken for pH and blood gas analysis. The animals were then injected with atipamezole and the recovery time was recorded. A combination of 500 mg zolazepam, 500 mg tiletamine, 500 mg xylazine, and 1000 mg (10 ml) ketamine, administered in a dosage of 1 ml per 100-150 kg bodyweight (depending on the species), proved to be most reliable and effective. The combination resulted in a fast immobilization. In all animals slight respiratory depression was seen, which indicates that oxygen suppletion may be needed for long-lasting immobilization. After reversal of the xylazine component, almost all animals recovered within 4 minutes. No long term adverse effects were reported by the owners.     

Continuous intravenous anesthesia in dogs using a combination of xylazine, ketamine and guaifenesin]

The tested anaesthesia through a permanent infusion of a xylazine, ketamine and guaifenezine (XKG) mixture was used in ten experimental dogs without clinical signs of a disease and in fifty two patients during different surgical interventions. After joint i.m. atropine (0.05 mg/kg) and xylazine (2 mg/kg) premedication, anaesthesia in dogs was induced by an i.v. administration of 1% ketamine at a dose of 2 mg/kg, and the XKG was infused instantly after the previous treatment. The mixture contained 2.0 ml of 5% ketamine and 1.25 ml of 2% xylazine added to 100 ml of 5% guaifenezine. The infusion was applied at a rate of 3.3 ml/kg for the first five minutes and then it was maintained at constant values of 2.2 ml/kg during the whole surgical intervention (Tab. I). The induction and course of anaesthesia, and waking up and recovery from anaesthesia were evaluated in all dogs, and the trias values were also followed. These additional parameters were followed in the test group: breathing volumes, ECG values and acid-base balance parameters were determined from the collected blood samples. The observation of measurable parameters (Figs. 1 to 5) and ECG analysis did not demonstrate any large departures from the starting values, and the changes in the acid-base balance (Tab. II) suggest the partly compensated respiratory acidosis. On the basis of our results, we can recommend this tested method for general anaesthesia particularly of dogs of larger breeds and for longer-lasting operations. This method is suitable to be used first of all in the veterinary establishments where inhalation anaesthesia is not practicable.     

Observations on some cardiopulmonary effects of midazolam, xylazine and a midazolam/ketamine combination in the goat

Xylazine, midazolam and a midazolam/ketamine combination were administered to 6 goats in a randomised 3-way block design. All goats received all treatments with at least a 7-day interval between treatments. Statistically significant (P < 0.05) changes were observed in some of the measured cardiopulmonary variables for xylazine and midazolam/ ketamine. Xylazine administration resulted in statistically significant decreases in minute volume, arterial partial pressure of oxygen, heart rate and mean arterial blood pressure. The increase in arterial partial pressure of carbon dioxide was not statistically significant. For the midazolam/ketamine combination, the decrease in tidal volume was statistically significant, but not the decrease in minute volume and increase in arterial partial pressure of carbon dioxide. The decrease in the arterial partial pressure of oxygen was also statistically significant. The mean arterial blood pressure for the combination was statistically significantly higher compared to xylazine. The changes in cardiopulmonary variables after midazolam administration were not statistically significant, such as tidal and minute volume, arterial partial pressure of oxygen and carbon dioxide. However, clinically significant effects such as hypoventilation and hypoxia were observed after its administration. The change in mean arterial blood pressure was minimal.     

Pharmacokinetics of cyclosporine in woodchucks and Pekin ducks

The purpose of this study was to evaluate the pharmacokinetics of cyclosporine (Cy) in woodchucks ( Marmota monax ) and Pekin ducks. These data are needed to design rational dosing regimens. Pharmacokinetic parameters were calculated from blood concentration-time data obtained following intravenous (i.v.) administration of 10 mg/kg body weight to woodchucks and Pekin ducks. Whole blood samples were collected in EDTA and assayed using a commercially available radioimmunoassay kit that employs a monoclonal antibody specific for Cy. The blood concentration-time profile best Dtted an open, two-compartmental model in Pekin ducks. Compartmental analysis of data in woodchucks did not adequately describe the data. When non-compartmental pharmacokinetic analysis of the data was performed, the resulting mean (± SD) pharmacokinetic parameters in woodchucks and Pekin ducks, respectively, were as follows: volume of distribution at steady-state, 2.9 (± 0.8) and 2.7 (± 0.2) L/kg; systemic clearance, 10.2 (± 2.8) and 28.6 (± 6.1) mL/kg/min; mean residence time, 4.8 (± 1.1) and 1.6 (± 0.3). These data suggest that Pekin ducks clear Cy at a faster rate than do woodchucks and that a greater dose of Cy should be administered to Pekin ducks in order to achieve adequate immunosuppression.     

A balanced anesthesia with a combination of xylazine, ketamine and butorphanol and its antagonism by yohimbine in pigs.

The effects of intramuscular injections of xylazine (2 mg/kg)-ketamine (15 mg/kg) [X-K15], and xylazine (2 mg/kg)-ketamine (5 mg/kg)-butorphanol (0.22 mg/kg) [X-K5-B] were compared in atropinized (0.05 mg/kg) miniature pigs (pigs). Both combinations induced the anesthesia for more than 1 hr, however X-K5-B induced the more potent and well balanced anesthesia as compared with X-K15, although the amount of ketamine was reduced to one third. The duration of loss of pedal reflex, an indicator of surgical anesthesia, in X-K5-B (62 +/- 13 min) was significantly (P less than 0.05) longer than in X-K15 (28 +/- 19 min). In addition, X-K5-B was accompanied by loss of laryngeal reflex in all pigs. Recovery from anesthesia in X-K5-B was much smoother than in X-K15, and the administration of yohimbine (0.05 mg/kg) could rapidly and smoothly reverse the anesthesia induced by X-K5-B, although it was accompanied by a transient fall in blood pressure and tachycardia. The combination of xylazine, ketamine and butorphanol appears to be a relatively safe and widely available anesthesia for the period of one hour in pigs.     

Use of the anesthetic combination of tiletamine,zolazepam, ketamine,and xylazine for neutering feral cats

OBJECTIVE: To evaluate the use of the anesthetic combination tiletamine, zolazepam, ketamine, and xylazine (TKX) for anesthesia of feral cats at large-scale neutering clinics. DESIGN: Original study. ANIMALS: 7,502 feral cats. PROCEDURE: Cats were trapped by their caretakers for a feral cat neutering program from July 1996 to August 2000. The anesthetic combination TKX was injected IM into cats while they remained in their traps. Each milliliter of TKX contained 50 mg of tiletamine, 50 mg of zolazepam, 80 mg of ketamine, and 20 mg of xylazine. Females were spayed by veterinarians, whereas males were castrated by veterinarians or veterinary students. Yohimbine (0.5 mg, IV) was administered at the end of the procedure. Logs were kept of the individual drug doses, signalment of the cats, and any complications encountered. These data were analyzed retrospectively (1996 to 1999) and prospectively (2000). RESULTS: Of the 5,766 cats for which dosing records were complete, 4,584 (79.5%) received a single dose of TKX. The mean initial dose of TKX was 0.24 +/- 0.04 ml/cat, and the total mean dose of TKX was 0.27 +/- 0.09 ml. Overall mortality rate was 0.35% (26/7,502) cats, and the death rate attributable solely to potential anesthetic deaths was 0.23% (17/7,502) cats. CONCLUSIONS AND CLINICAL RELEVANCE: The use of TKX for large-scale feral cat neutering clinics has several benefits. The TKX combination is inexpensive, provides predictable results, can be administered quickly and easily in a small volume, and is associated with a low mortality rate in feral cats.     

Hematologic and serum chemical effects of a ketamine/xylazine combination when used for immobilizing springbok

A ketamine hydrochloride/xylazine combination was found effective for immobilizing springbok. Following intramuscular injection by hand, the onset of immobilization ranged from 3 to 10 minutes and duration of immobilization ranged from 1 hour to 2 hours 20 minutes. Hematologic and serum chemical values before and after immobilization were compared. Serum alanine transaminase and serum glucose values were significantly higher after immobilization, whereas serum potassium was significantly lower.     

Cardiopulmonary effects of administration of a combination solution of xylazine, guaifenesin, and ketamine or inhaled isoflurane in mechanically ventilated calves

OBJECTIVE: To compare the cardiopulmonary effects of administration of a solution of xylazine, guaifenesin, and ketamine (XGK) or inhaled isoflurane in mechanically ventilated calves undergoing surgery. ANIMALS: 13 male calves 2 to 26 days of age. Procedures-In calves in the XGK group, anesthesia was induced (0.5 mL/kg) and maintained (2.5 mL/kg/h) with a combination solution of xylazine (0.1 mg/mL), guaifenesin (50 mg/mL), and ketamine (1.0 mg/mL). For calves in the isoflurane group, anesthesia was induced and maintained with isoflurane in oxygen. The rates of XGK infusion and isoflurane administration were adjusted to achieve suitable anesthetic depth. All calves received 100% oxygen and were mechanically ventilated to maintain end-tidal carbon dioxide concentrations from 35 to 40 mm Hg and underwent laparoscopic bladder surgery through an abdominal approach. Cardiopulmonary variables were measured before induction and at intervals up to 90 minutes after anesthetic induction. RESULTS: The quality of induction was excellent in all calves. The XGK requirements were 0.57 +/- 0.18 mL/kg and 2.70 +/- 0.40 mL/kg/h to induce and maintain anesthesia, respectively. Heart rate was significantly lower than baseline throughout the anesthetic period in the XGK group. Systolic arterial blood pressure was significantly higher in the XGK group, compared with the isoflurane group, from 5 to 90 minutes. Cardiac index was lower than baseline in both groups. Differences between groups in cardiac index and arterial blood gas values were not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of XGK resulted in excellent anesthetic induction and maintenance with cardiopulmonary alterations similar to those associated with isoflurane in mechanically ventilated calves.     

Lysine requirement of growing male Pekin ducks

1. One growth experiment and one balance test were conducted to study the response to increasing levels of dietary lysine supplementation in male Pekin ducks with special reference to the growth periods from 1 to 3 weeks and 4 to 7 weeks of age. 2. Two different low-lysine diets were used as basal diets in both periods. The basal lysine levels were 7.6 g/kg (d 1 to 21) and 6.2 g/kg (d 22 to 49) and the ranges in lysine concentration were 7.6 to 12.6 g/kg (d 1 to 21) and 6.2 to 11.2 g/kg (d 22 to 49). 3. Growth performance, feed conversion efficiency and meat yield increased ( P < 0.05) with increas6 ing lysine concentration (requirement defined as 95% of the asymptote). 4. It is concluded that the dietary lysine concentration should be 0.93 g/MJ nitrogen corrected apparent metabolisable energy (AME N ) (11.7 g/kg) for the starter period (until d 21) and 0.75 g/MJ AME N (10.0 g/kg) for the grower period (from d 22 onwards).     

Effects of stocking density on growth performance,meat quality and tibia development of Pekin ducks

This study was performed to investigate the effects of stocking density on performance, meat quality and tibia development in Pekin ducks reared on a plastic wire floor. A total of 372 healthy, 21‐day‐old, male ducks with similar body weight (BW) were randomly allotted to stocking densities of five (low), eight (medium) and 11 (high) birds/m². Each group had six replicates. Results showed that compared with the low density group, medium and high stocking density caused a decrease in final BW at 42 days old, and in average daily gain, European performance index (p < .01) and meat pH at 45 min postmortem (p < .001), and an increase of meat drip loss (p < .01). High stocking density resulted in an increase of feed/gain ratio (p < .001), but a decrease of tibia calcium (p < .01) and phosphorus content (p < .05). Meat color, shear force values, tibia size (weight, length, and width) and breaking strength were not significantly influenced by stocking density. In conclusion, stocking density over eight birds/m² negatively affects growth performance, but meat quality and tibia development are not dramatically influenced. Based on this study, the stocking density of male Pekin ducks should be adjusted between five and eight birds/m².     

北京鸭源鹅出血性多瘤病毒的分子检测

鹅出血性多瘤病毒(Goose hemorrhagic polyomavirus,GHPyV)是鹅出血性肾炎肠炎的致病病原,迄今为止,国际上已从鹅、番鸭和半番鸭中检测到GHPyV。为了解北京鸭是否存在GHPyV的感染,本研究从北京、山东、河北、河南等地的北京鸭种鸭场采集肝脾组织样品68份,并用GHPyV特异性PCR进行了检测。结果显示,从5份肝脾组织样品中检出GHPyV的VP1基因。选一株北京鸭源GHPyV(106株)测定了基因组序列。测序结果显示,北京鸭源GHPyV基因组长度为5 254bp,相对于德国鹅源GHPyV毒株Germany 2001,106株基因组在其编码区共有10个碱基位发生突变,但只有2个碱基位的突变引起氨基酸的置换;此外,106株基因组的非编码区存在2个核苷酸的缺失。对不同水禽来源的GHPyV基因组序列进行比较的结果表明,GHPyV的基因组序列具有高度保守性。由于GHPyV可感染鹅、番鸭、半番鸭和北京鸭,表明该病毒具有较广泛的宿主范围。     

Effects of xylazine/ketamine on cardiac function and serum ionised calcium in horses

Haemodynamic variables, with emphasis on right ventricular (RV) contractility, were measured in horses prior to, during and following anaesthesia with xylazine/ketamine. In an attempt to elicit mechanisms of anaesthetic-induced alteration of myocardial function, serum ionised and total calcium concentrations were also measured. Xylazine caused decreased cardiac function, including RV contractility, that was not reversed immediately by ketamine but was insignificant from pre-anaesthetic baseline by recovery (45 min following induction). Serum ionised and total calcium concentrations did not change.     

Chemical restraint of African mole‐rats (Fukomys sp.) with a combination of ketamine and xylazine

ObjectiveTo establish an accurate anaesthetic dose for chemical restraint of African mole-rats using ketamine and xylazine.Study designProspective nonrandomized laboratory study.AnimalsSixteen adult Ansell’s mole-rats (Fukomys anselli) and eight giant mole-rats (F. mechowii).MethodsFukomys anselli of different ages, sexes and reproductive status were systematically anaesthetized starting with an intramuscular injection of ketamine (2.5 mg kg⁻¹) and increasing the doses in steps of 0.5 mg kg⁻¹ until loss of the righting reflex (LRR) was observed. Xylazine was added to a constant dose of ketamine, starting at 0.5 mg kg⁻¹ that was increased by 0.5 mg kg⁻¹ in further trials. Once an effective combination was established and evaluated in F. anselli, it was also tested in F. mechowii. Heart and respiratory rates and rectal temperatures were measured during anaesthesia. anova for repeated measures and Student’s t-test were used to compare means.ResultsChemical restraint was accomplished at a dose of 6 mg kg⁻¹ ketamine combined with 2.5 mg kg⁻¹ xylazine. LRR lasted on average mean 56 ± SD 19 minutes (F. anselli) and 140 ± 41 minutes (F. mechowii). Loss of pedal withdrawal reflex (LPR) lasted for 20 ± 15 minutes (F. anselli) and for 29 ± 2 minutes (F. mechowii), respectively. All animals recovered satisfactorily. Heart and respiratory rates were stable during anaesthesia, but rectal temperature fell significantly in F. mechowii after losing the righting reflex (LRR) from T1 (32.6 ± 0.6 °C) to T3 (30.4 ± 0.9 °C).Conclusions and Clinical relevanceAfrican mole-rats (Bathyergidae) live in closed burrow systems under particular conditions (hypercapnia, hypoxia, stable temperature, humidity, darkness) and show several physiological adaptations. Injectable anaesthetics in the dose rates used in other rodents are not appropriate for use in these subterranean species. Here, a reliable protocol for chemical restraint is provided.     

Anesthetic and physiologic effects of tiletamine, zolazepam, ketamine, and xylazine combination (TKX) in feral cats undergoing surgical sterilization

Tiletamine (12.5 mg), zolazepam (12.5 mg), ketamine (20 mg), and xylazine (5 mg) (TKX; 0.25 ml, IM) combination was evaluated as an anesthetic in 22 male and 67 female adult feral cats undergoing sterilization at high-volume sterilization clinics. Cats were not intubated and breathed room air. Oxygen saturation (SpO(2)), mean blood pressure (MBP), heart rate (HR), respiration rate (RR), and core body temperature were recorded. Yohimbine (0.25 ml, 0.5 mg, IV) was administered at the completion of surgery. TKX produced rapid onset of lateral recumbency (4+/-1 min) and surgical anesthesia of sufficient duration to complete surgical procedures in 92% of cats. SpO(2) measured via a lingual pulse oximeter probe averaged 92+/-3% in male cats and 90+/-4% in females. SpO(2) fell below 90% at least once in most cats. MBP measured by oscillometry averaged 136+/-30 mm Hg in males and 113+/-29 mm Hg in females. MBP increased at the onset of surgical stimulation suggesting incomplete anti-nociceptive properties. HR averaged 156+/-19 bpm, and RR averaged 18+/-8 bpm. Neither parameter varied between males and females or over time. Body temperature decreased significantly over time, declining to 38.0+/-0.8 degrees C at the time of reversal in males and 36.6+/-0.8 degrees C at the time of reversal in females. Time from anesthetic reversal to sternal recumbency was prolonged (72+/-42 min). Seven cats (8%) required an additional dose of TKX to maintain an adequate plane of anesthesia at the onset of surgery, and this was associated with significantly longer recovery times (108+/-24 min).