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In this study, anesthesia levels obtained with tiletamine-zolazepam (TZ) and ketamine-midazolam (KM) with or without xylazine (X) were compared in rabbits. Reflexes (corneal, palpebral and withdrawal), blood parameters (PaO2, PaCO2, pH and ions HCO3-), cardiovascular function (heart rate and mean arterial blood pressure) and body temperature were evaluated before and after the injections of the anesthetic combination in the same rabbits (n = 10). With KM and TZ, no suppression of reflexes occurred. The body temperature and pH decreased and HCO3- increased similarly to KMX et TZX. Some physiological and blood parameters were less (PAM, PaCO2) and not (PaO2) affected comparatively to KMX et TZX. These protocols were of short duration of action and did not offer any anesthesia or analgesia. Therefore, their utilization should be restricted to short procedures where no painful manipulations are performed. Ketamine-midazolam-xylazine and tiletamine-zolazepam-xylazine on the other hand are indicated for interventions that require anesthesia. With these combinations, all reflexes were absent for 30-45 and 60-90 min following injections of KMX et TZX, respectively. However, these combinations induce cardiac depression, as well as a decrease of all measured blood parameters and body temperature and a reduction of PaO2. Supplementation with oxygen is recommended with the introduction of xylazine in the protocol.

In this study, done in the context of normal veterinary practice, the possibilities of using Memoprint have been evaluated. The values of systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and pulse rate (PR) in healthy cats (n = 72) have been determined, as well as the values of SAP, DAP and PR before (n = 26), during (n = 40) and after (n = 16) an anaesthesia for routine surgery. The results show that Memoprint allows a quick, convenient and correct determination of SAP (average: 122.7 mmHg) and DAP (88.5), but an imprecise determination of the PR. The measures are not highly repeatable with conscious cats (SAP: 0.68, DAP: 0.51), unlike that obtained before (0.90, 0.86), during (0.96, 0.90) and after (0.88, 0.58) the anaesthesia, indicating once again the importance of the cats' familiarity and cooperation with the veterinarian. An analysis of the variance of the values of blood pressure shows their direct relationship with age, sex, breed and style of life of the cats and an increase in pressure in those over ten years of age.

Determinations of renal plasma flow (RPF), glomerular filtration rate (GFR) and urine flow in sheep fed low protein diets have yielded controversial data. In the present experiment, 8 sheep were fed a regular diet and another 6 received a low protein ration. Water intake and urine output were measured over 10 days. RPF and GFR were determined on 2 consecutive days. The latter determinations were repeated on 5 anaesthetized animals (sodium thiopental) in each group. An important increase in water intake (58%) and urine output (98%) was observed in the sheep on the low protein diet. In these animals, blood urea averaged 0.1 g/l. Urine output was greater (with a lower osmolarity) when the blood urea level was the lowest. RPF and GFR were significantly lower in the sheep on the low protein diet (RPF: 13.5 versus 28.1 ml/min/kg in the control animals; GFR: 1.61 versus 4.01 ml/min/kg); no relationship could be established with the blood urea level. The only effect of the anaesthesia was a reduction in RPF, of the same magnitude in both groups of sheep (about 35%). In conclusion, when sheep are fed a low protein diet, the volume of plasma processed through the kidney is decreased. In the present experiment, the increased urine flow and the lowered urinary osmolarity indicate an impaired renal concentrating ability. Barbiturate anaesthesia does not affect this phenomenon.

Respiratory secretions and bronchoalveolar cells can be repeatedly harvested from anaesthetized pigs. This lung washing procedure is characterized by its anaesthesia conditions and by getting an apnae through a hyperbaric oxygenation, which suppresses any risk. Radiography analysis indicates that whole cardiac and diaphragmatic pulmonary lobes are lavaged by this method.

Lactic acid, glucose, creatine phosphokinase (CPK) and some mineral components were determined in the blood of piglets before and after a halothane test of five minutes (only before for CPK). Two different experimental groups were studied: 222 Pietrain piglets from an INRA experimental herd, and 325 piglets from the Large White, French Landrace and Belgian Landrace breeds entering performance testing stations. Animals reacting positively to halothane ("MHS" piglets) have significantly higher blood levels of lactic acid and potassium before anesthesia than normal animals. CPK is also higher, except for the Belgian Landrace: in this breed CPK shows the same average value and distribution in the two groups of piglets (normal and MHS). There are also breed differences in blood magnesium, independently of the reaction to halothane. But the breed differences observed in lactic acid and CPK are related to the proportion of MHS piglets in each breed. Anesthesia by means of halothane lowers the measured blood characteristics--except for glucose--in normal animals, and rises them--except for potassium--in MHS piglets. The results are discussed in view of the incomplete discrimination between the two types of pigs, with a 5 minutes test, and, particularly, considering possible breed differences in that respect.

Different mechanisms are involved in drug interactions, especially between anesthetics and drug administrated before and during anesthesia: liver disease, bioavailability related to the route of administration, displacement of the protein-bound of the part, etc. Two peculiarities of veterinary anesthesiology were found useful to evaluate such drug interactions: changes in the frequency of the cyclic contraction of the reticulum (sheep) and decrease in the central body temperature (cat). These criteria were used in addition to electroencephalographic recordings to appreciate the inhibition of microsomal penthiobarbital metabolism by chloramphenicol, the effect of phenylbutazone on plasma-protein displacement and the non-bioavailability of chloramphenicol by the subcutaneous route.