Comparison of xylazine and lidocaine effects for analgesia and cardiopulmonary functions following lumbosacral epidural injection in goats

The present study was carried out in order to compare the effects of xylazine and lidocaine on analgesia and cardiopulmonary parameters following epidural injection in goats. Twelve healthy Small East African goats of both sexes (mean +/- SD; 15.6 +/- 1.9 kg body weight) were used. The goats were randomly assigned to two groups of five and seven animals. The first group (n = 5) was given 2% lidocaine-HCl at 4400 micrograms/kg body weight. The second group (n = 7) was administered 2% xylazine-HCl at 150 micrograms/kg body weight. All drugs were diluted in 5 ml of sterile water and were injected epidurally through the lumbosacral interspace with the injection taking over 20 s. Both drugs induced analgesia within 5 min. Signs of sedation, cardiopulmonary changes and lateral recumbency developed within 5-7 min after administration of epidural xylazine. Tail flaccidity and hind limb paralysis developed 3 min after epidural administration of lidocaine. The time from recumbency to regaining normal stance was 60 and 158 min for xylazine- and lidocaine-treated animals respectively. Xylazine induced adequate analgesia of the flank and perineum, which extended to the head and forelimbs. In contrast, lidocaine induced adequate bilateral flank and perineal analgesia extending up to the third thoracic vertebra. For both drugs, analgesia of the flank and perineum persisted for the entire 180-min observational period. Epidural injection of xylazine and lidocaine caused variable depression effects on the cardiopulmonary values but was not so low as to cause concern. It is concluded that lumbosacral epidural injection of xylazine at 150 micrograms/kg body weight in 5 ml of water for injection offers the most desirable sedation and analgesia of the flank and perineum. The longer duration of analgesia may be useful for postoperative analgesia and relief of continuous straining in goats.     

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.     

Analgesic and systemic effects of ketamine,xylazine, and lidocaine after subarachnoid administration in goats

OBJECTIVE: To determine the effects of ketamine hydrochloride, xylazine hydrochloride, and lidocaine hydrochloride after subarachnoid administration in goats. ANIMALS: 6 healthy goats. PROCEDURE: In each goat, ketamine (3 mg/kg), xylazine (0.1 mg/kg), lidocaine (2.5 mg/kg), and saline (0.9% NaCI) solution were injected into the subarachnoid space between the last lumbar vertebra and first sacral vertebra (time 0). Analgesic, ataxic, sedative, cardiovascular, and respiratory effects and rectal temperature were evaluated before (baseline) and 2, 5, 10, 15, and 30 minutes after administration and at 30-minute intervals thereafter as needed. RESULTS: Administration of anesthetics induced varying degrees of analgesia. Onset of the analgesic effect was more delayed for xylazine (mean +/- SD, 9.5 +/- 2.6 minutes) than for ketamine (6.7 +/- 2.6 minutes) or lidocaine (3.5 +/- 1.2 minutes). Duration of analgesia induced by xylazine (88.3 +/- 15 minutes) was twice as long as the duration of analgesia induced by ketamine (48.8 +/- 13.5 minutes) but similar to that induced by lidocaine (66.5 +/- 31 minutes). Xylazine induced bradycardia, whereas ketamine caused a nonsignificant increase in heart rate. Xylazine induced a reduction in arterial pressure, whereas ketamine or lidocaine did not affect arterial pressure. CONCLUSIONS AND CLINICAL RELEVANCE: Subarachnoid administration of xylazine in goats resulted in longer duration of analgesia of the tail, perineum, hind limbs, flanks, and caudodorsal rib areas than administration of ketamine or lidocaine. However, xylazine caused bradycardia and respiratory depression. Additional studies are needed to determine whether the analgesia would be sufficient to allow clinicians to perform surgical procedures.     

The comparative haematology of cross-bred and indigenous East African goats of Tanzania and breeds reared in Denmark

Erythrocyte counts, haematocrit, haemoglobin concentration, red blood cell indices, total and differential leukocyte counts were determined in 202 cross-bred and 14 indigenous East African goats aged 6–12 months and also in 59 Norwegian dairy goats, of which 24 were 15–45 days old, 8 were 8 months old and 27 were over 3 years and pregnant. These were reared in Tanzania. Comparisons were made with 24 Dwarf and 57 Danish Landrace goats at 6–12 months of age and 76 adult pregnant Danish Landrace goats reared in Denmark. The purpose was to determine reference ranges for cross-bred and indigenous East African goats and to compare these with those of other breeds. The haemoglobin concentration, haematocrit, erythrocyte and white blood cells were lowest in the Norwegian kids. The highest values were observed in 6–12-month-old goats in all the breeds, whereafter they decreased to relatively constant adult levels. The mean corpuscular volumes were highest in kids followed by adult pregnant Norwegian and Danish Landrace goats, and lowest in 6–12 months old goats. East African and cross-bred goats had the smallest mean corpuscular volumes. The haemoglobin concentration, erythrocyte and leukocyte counts were highest in indigenous East African, followed by young Norwegian and cross-bred goats. The mean corpuscular haemoglobin concentration was highest in the cross-breds, while the mean corpuscular haemoglobin was higher in pregnant than in other goats. The age and breed differences were statistically significant.     

Caudal epidural analgesia induced by xylazine administration in cows

Xylazine (0.05 mg/kg of body weight diluted to a 5-ml volume, using 0.9% NaCl) or 5 ml of 0.9% NaCl was administered epidurally into the first caudal intervertebral space (Co1-Co2) in 8 cows (mean +/- SD body weight, 583 +/- 150 kg). Cows were observed for responses to deep needle pricking of the caudal dermatomes (S3 to Co), sedation, and ataxia. Heart rate, respiratory rate, body temperature, rate of ruminal contractions, coccygeal arterial blood pressure, pHa, blood gas tension (PaO2, PaCO2), base excess, total solids concentration, and PCV were determined before and after xylazine administration. Epidurally administered xylazine induced sedation and selective (S3 to Co) analgesia for at least 2 hours. Mild ataxia of hind limbs was observed in 6 cows, but all cows remained standing. Heart rate, respiratory rate, rate of ruminal contractions, arterial blood pressure, PaO2, PCV, and total solids concentration were significantly (P less than 0.05) decreased, and PaCO2, base excess, and bicarbonate concentration were significantly (P less than 0.05) increased after xylazine administration. Epidurally administered 0.9% NaCl did not alter sensory perception to needle pricking and did not affect any of the physiologic variables determined. Although epidural administration of xylazine induced analgesia and sedation in healthy cows, it should be avoided for epidural analgesia in cattle with heart disease, lung disease, and/or gastrointestinal disease because of its potent cardiopulmonary and ruminal depressant effects.     

Cardiovascular and allied actions of xylazine and atropine in the unanaesthetized goat

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.     

Behavioral and Cardiopulmonary Effects of a Constant Rate Infusion of Remifentanil–Xylazine for Sedation in Horses

Xylazine and remifentanil in constant rate infusion (CRI) could be used for sedation in horses without adverse effects. The objective was to evaluate behavioral and cardiopulmonary effects of an intravenous (IV) infusion of xylazine and remifentanil for sedation in horses. Xylazine (0.8 mg/kg IV) followed after 3 minutes by a CRI of xylazine and remifentanil (0.65 mg/kg/h and 6 μg/kg/h, respectively) was administered in 10 healthy horses for 60 minutes. Sedation, ataxia, and cardiopulmonary, hematological, and blood gases variables were evaluated. Heart rate decreased significantly during the first 25 minutes after CRI of xylazine and remifentanil, whereas the respiratory rate showed a significant decrease at 20 minutes and remained significantly low until the endpoint. There were no statistically significant fluctuations in blood arterial pressure, blood pH, partial pressure of arterial carbon dioxide, lactate, creatinine, calcium, chlorine, and sodium, compared with baseline values. Blood partial pressure of arterial oxygen and bicarbonate values were significantly higher compared with baseline values, whereas potassium decreased. Sedation and ataxia developed immediately after the administration of xylazine in all horses. All horses recovered successfully within 10 minutes after interruption of the CRI of xylazine and remifentanil, with no ataxia. No adverse effects were observed. The use of a combination of xylazine and remifentanil as sedation protocol has no adverse effects at the described dosage.     

Analgesic and systemic effects of xylazine, lidocaine and their combination after subarachnoid administration in goats

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.     

Comparative analgesia of xylazine, xylazine/morphine, xylazine/butorphanol, and xylazine/nalbuphine in the horse, using dental dolorimetry

Xylazine, morphine, butorphanol, and nalbuphine were evaluated in 5 adult male horses, using dental dolorimetry. Comparisons were made at 30, 60, and 100 minutes after IV drug administration. Peak analgesia and the time to develop peak analgesia also were compared. Xylazine induced a marked increase in the tooth pulp pain threshold measurements as did the xylazine/narcotic combinations. Statistical differences were not detectable between these treatments. Xylazine and xylazine/butorphanol were better analgesics than was butorphanol alone at 30 and 60 minutes. Xylazine resulted in peak analgesia faster than did butorphanol or the combination of xylazine/butorphanol. Additive analgesic effects were not detected with the combined treatments.     

A comparison of subarachnoid buprenorphine or xylazine as an adjunct to lidocaine for analgesia in goats

ObjectiveTo test the hypothesis that subarachnoid administration of buprenorphine and lidocaine provides more intense and longer lasting perioperative analgesia with less side effects than xylazine and lidocaine in goats.Study designRandomized, blinded, controlled study.Study animals Ten healthy female goats randomly assigned to two groups of five animals each.MethodsAfter sedation with acepromazine (0.1 mg kg^?1) intravenously (IV), lidocaine 2% (0.1 mL kg^?1) combined with either xylazine (0.05 mg kg^?1; Group X) or buprenorphine (0.005 mg kg^?1; Group B) were injected intrathecally at the lumbo-sacral junction prior to stifle surgery. Electrocardiogram, heart rate, direct systolic, mean, and diastolic arterial blood pressures, rectal temperature and arterial blood gases were recorded as were post-operative sedation and pain scores using a visual analogue and numeric rating scale, respectively. Data were analyzed with one-way anova for repeated measures, one-way anova, Friedman's and Kruskal–Wallis tests as necessary (p< 0.05).ResultsSurgery was successfully performed under both analgesia protocols. Total pain and sedation scores were significantly lower in the B as compared with X group from 3–24 hours and 30–120 minutes, respectively after subarachnoid drug administration (SDA). Heart rate and arterial blood pressures decreased post SDA and were consistently lower in X versus B (p< 0.05). In B arterial blood gas parameters did not change post SDA, but in group X PaCO₂ increased slightly within 15 minutes of SDA and remained elevated for at least 3 hours (p< 0.05).ConclusionIn these goats intrathecal administration of buprenorphine and lidocaine produced more profound and longer lasting analgesia with less sedation and hemodynamic and respiratory impairment than xylazine with lidocaine.Clinical relevanceIn these goats undergoing hind limb surgery, subarachnoid buprenorphine/lidocaine offered more intense and longer lasting analgesia than a xylazine/lidocaine combination, with less sedation and impairment of cardiopulmonary function.     

Stress associated with road transportation in desert sheep and goats, and the effect of pretreatment with xylazine or sodium betaine

The present work investigates some clinical, endocrinological, biochemical and haematological variables in desert sheep and goats stressed in the course of individual road transportation, and the influence thereon of pretreatment with an established anti-stressor drug, xylazine HCl, and a test compound, sodium betaine (trimethylglycine). Road transportation for 2h resulted in variable and statistically insignificant increases in heart, pulse and respiratory rates in both control and experimental animals. Transportation stress significantly increased the concentrations of plasma cortisol, and glucose, and decreased that of magnesium. The endogenous thiocyanate concentration was unaffected. The stress also insignificantly decreased the haematocrit (PCV), and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep and goats with xylazine at a single dose of 0.01 mg/kg by the intravenous route significantly ameliorated the effects induced by the stressful stimulus. The effects of pretreatment of the two species with sodium betaine (10 mg/kg) produced variable and insignificant effects.     

Some Blood Parameters of the Yellowfish (Barbus Holubi) and the Barbel (Clarias Gariepinus)

Haemoglobin concentrations, haematocrit values, red blood cell counts, red blood cell diameter, white blood cell counts and plasma haemoglobin concentrations were performed on the yellowfish (Barbus holubi) and the barbel (Clarias gariepinus). Wide variations were observed in haematocrit values and haemoglobin concentrations and statistically significant correlations existed between mean corpuscular volume and average corpuscular haemoglobin and between the red blood cell count and mean corpuscular volume in the case of the yellowfish and between the red blood cell count and haemoglobin concentration in the case of the barbel. It was found that the determination of one variable is not sufficient for the routine assessment of other haematological parameters in these fish due to poor correlations observed. This can only be done in the case of the variables mentioned.     

Caudal epidural analgesia in cattle using xylazine.

Each of 25 mature Holstein cows were given a single 5 mL epidural injection of one of four different concentrations of xylazine or saline. The onset, magnitude and duration of caudal epidural analgesia was quantitated with the use of a low voltage DC current applied to the perineal area. The dose that produced the longest duration of analgesia and produced the least ataxia or sedation was approximately 0.05 mg/kg (25 mg in 5 mL diluent). The analgesia produced by this xylazine dose was compared to a standard dose of epidural lidocaine (100 mg/5 mL) by the same method. To investigate the role of systemic absorption in the production of epidural analgesia, the previously utilized epidural xylazine dosage was given intramuscularly to four adult cows. Analgesia was quantitated as before and the results compared with epidural xylazine. Epidural xylazine produced a significantly greater duration of analgesia, as measured by this model, than did epidural lidocaine. Xylazine, given epidurally, produced greater perineal analgesia than did xylazine given intramuscularly.     

Clinicophysiological Effects of Spinally Administered Ketamine and Its Combination with Xylazine and Medetomidine in Healthy Goats

The study was conducted in 9 healthy adult goats of either sex, weighing 15–20 kg, to evaluate and compare the clinicophysiological effects of spinally administered ketamine alone and in combination with xylazine and medetomidine. Nine trials each of the three treatments were conducted randomly by injecting ketamine (2.5 mg/kg) (n = 9), ketamine and xylazine (2.5 mg/kg and 0.05 mg/kg) (n = 9) and ketamine and medetomidine (2.5 mg/kg and 10 μg/kg) (n = 9). The drugs were administered at the lumbosacral subarachnoid space under strict aseptic conditions. The treatments were evaluated on the basis of clinicophysiological, haematological, biochemical and haemodynamic observations. Ketamine produced mild to moderate analgesia of the hindquarters. Its combination with either xylazine or medetomidine produced complete analgesia of the hindquarters for 45–60 min. Ataxia was moderate in the ketamine group, whereas animals attained sternal recumbency in the combination groups. A moderate degree of sedation was recorded in the combination groups. Heart rate and respiratory rate depression in the combination groups and heart rate and respiratory rate stimulation in ketamine group were recorded. Haematological parameters decreased in all the groups. Increase in serum glucose, creatinine and urea nitrogen was recorded in all the groups. Serum electrolytes did not show any significant change. The results showed that the combination of ketamine with xylazine or medetomidine at these dose rates produced a comparable degrees of analgesia of hindquarters with transient and minimal cardiopulmonary side effects.     

Preliminary Results of Behavioral and Cardiopulmonary Effects of a Constant Rate Infusion of Remifentanil–Xylazine for Sedation in Horses

Standing surgical procedures are performed commonly in horses under sedation. The use of a xylazine and remifentanil combination has not been investigated in horses. We proposed to evaluate behavioral and cardiopulmonary effects of an intravenous (IV) infusion of xylazine with remifentanil for sedation in horses. Xylazine (0.8 mg/kg IV) followed in 3 minutes by remifentanil (0.0005 mg/kg IV), and a constant rate infusion of xylazine and remifentanil (0.65 mg/kg/h; 0.0225 mg/kg/h, respectively) was administered in three horses. Heart rate, respiratory rate (RR), arterial blood pressures, quality of sedation, pH, partial pressure of arterial CO₂ (PaCO₂), partial pressure of arterial O₂ (PaO₂), ataxia, sedation, and sedation overall outcome were assessed. Heart rate and RR remained within normal values during sedation without significant changes from baseline. Systolic, mean, and diastolic arterial blood pressures were increased during sedation. There were no significant changes in pH, PaCO₂, and PaO₂. Sedation developed immediately after injection of xylazine in the three horses but did not increase after remifentanil bolus or IV infusion of both drugs. None of the mares had ataxia. Adverse effects during and after sedation were present: excitement, increase in locomotor activity, and decrease in the gastrointestinal motility. The combination of xylazine and remifentanil sedation protocol produces adverse effects. This protocol cannot be recommended for clinical conditions, at the described doses.     

Some clinical, haematological and biochemical effects of four tranquilizers in camels (Camelus dromedarius)

Six healthy camels were treated with the tranquilizers propionyl promazine (Combelen), xylazine (Rompun), acepromazine (Calmivet) or chlorpromazine (Largactil) at single intramuscular doses of 0.5, 0.25, 0.1, or 3 mg/kg, respectively; and the onset, duration and degree of sedation produced by each drug was assessed for six hours. The effect of the treatments on some haematological and biochemical parameters was also studied. The onset and duration of action of the tranquilizers were 10 min and 2.1 +/- 0.5 h for propionyl promazine, 4 min and 3.1 +/- 0.4 h for xylazine, 5 min and 2.3 +/- 0.5 h for acepromazine, 7 min and 2.5 +/- 0.4 h for chlorpromazine, respectively. It was observed that 5-10 min after the administration of the four drugs, camels showed slight irritability, dropping of the lower lips and scratching of the nostrils against objects. During the first hour after medication camels showed frequent urination, defaecation and lacrimation. Xylazine seemed to be superior to the other three drugs in producing sedation. No significant effect on the rectal temperature or the respiratory rates of treated camels was seen after the administration of the four drugs. There were consistent, but statistically insignificant decreases (about 10 p. 100) in the haemoglobin concentration and erythrocyte counts of camels one hour after treatment with the tranquilizers. The four drugs, particularly xylazine and propionyl promazine produced significant hyperglycaemia, but did not alter significantly the plasma concentration of urea or activity of aspartate aminotransferase.     

Sedative and cardiopulmonary effects of medetomidine hydrochloride and xylazine hydrochloride and their reversal with atipamezole hydrochloride in calves

OBJECTIVE: To assess the sedative and cardiopulmonary effects of medetomidine and xylazine and their reversal with atipamezole in calves. ANIMALS: 25 calves. PROCEDURES: A 2-phase (7-day interval) study was performed. Sedative characteristics (phase I) and cardiopulmonary effects (phase II) of medetomidine hydrochloride and xylazine hydrochloride administration followed by atipamezole hydrochloride administration were evaluated. In both phases, calves were randomly allocated to receive 1 of 4 treatments IV: medetomidine (0.03 mg/kg) followed by atipamezole (0.1 mg/kg; n = 6), xylazine (0.3 mg/kg) followed by atipamezole (0.04 mg/kg; 7), medetomidine (0.03 mg/kg) followed by saline (0.9% NaCl; 6) solution (10 mL), and xylazine (0.3 mg/kg) followed by saline solution (10 mL; 6). Atipamezole or saline solution was administered 20 minutes after the first injection. Cardiopulmonary variables were recorded at intervals for 35 minutes after medetomidine or xylazine administration. RESULTS: At the doses evaluated, xylazine and medetomidine induced a similar degree of sedation in calves; however, the duration of medetomidine-associated sedation was longer. Compared with pretreatment values, heart rate, cardiac index, and PaO(2) decreased, whereas central venous pressure, PaCO(2), and pulmonary artery pressures increased with medetomidine or xylazine. Systemic arterial blood pressures and vascular resistance increased with medetomidine and decreased with xylazine. Atipamezole reversed the sedative and most of the cardiopulmonary effects of both drugs. CONCLUSIONS AND CLINICAL RELEVANCE: At these doses, xylazine and medetomidine induced similar degrees of sedation and cardiopulmonary depression in calves, although medetomidine administration resulted in increases in systemic arterial blood pressures. Atipamezole effectively reversed medetomidine- and xylazine-associated sedative and cardiopulmonary effects in calves.     

Haematology and some blood chemical parameters of young carp till the age of three years

Haematological and biochemical analyses of blood were performed in carp (Cyprinus carpio L.) kept in small ponds. Caught and anaesthetised carp were clinically examined and blood samples were taken at regular intervals during the three years. In the first year of examinations, the haemoglobin and haematocrit values of carp fry significantly increased (P < 0.01) from June to September. The intensive growth of carp in the summer period in the second year was accompanied by adequate erythropoiesis. During hibernation haematocrit and haemoglobin significantly decreased (P < 0.05) and mean corpuscular haemoglobin concentration (MCHC) increased (P < 0.01) in both scaly and mirror carp. MCHC increased also with the age and increasing body weight of the fish. Mirror carp had lower haematocrit and haemoglobin values than scaly carp (P < 0.01). Comparative haematological analyses between carp of normal and poor body condition showed that moderate anaemia appeared in those with poor body condition. The results indicate that there is marked seasonal and age-dependent variation in the values of haematocrit and haemoglobin. Pond water quality investigations indicated good environmental conditions. A 50% increase (P < 0.05) of glucose concentration was found from June to September in the blood plasma of carp in the third year, accompanied by an even more increased (80%; P < 0.01) concentration of total lipids. At the same time, considerable changes of cholesterol and total protein concentrations were not observed. The results suggest that the investigated haematological and biochemical variables could be successfully utilised in monitoring the metabolic balance and health status of fish in intensive culture.     

Rechallenge of previously-infected pregnant ewes with Chlamydophila abortus

We studied some behavioural, clinical, biochemical and haematological variables in Desert (Najdi) sheep and goats subjected to the acute stressful stimulus of isolation from the flock, and the influence of pretreatment with xylazine (n = 6) or sodium betaine (n = 6). The isolation stress resulted in increased vocalization and in variable and statistically nonsignificant increases in heart, pulse and respiratory rates. Isolation caused significant increases in the plasma concentrations of cortisol (from about 35.2 to about 83.8 mmol/L) and glucose (from 3.1 to 4.2 mmol/L), and a decrease in that of magnesium (from 0.82 to 0.65 mmol/L). The endogenous thiocyanate concentration was unaffected. The isolation stress also significantly decreased the haematocrit (PCV), and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep and goats with xylazine at a dose of 0.01 mg/kg by the intravenous route significantly ameliorated the effects induced by the stressful stimulus. The effects of pretreatment of the two species with sodium betaine (10 mg/kg) produced variable and nonsignificant effects. There were no significant differences between sheep and goats in the responses to the isolation stress, except in vocalization, which was greater in sheep than in goats.