Efficacy and safety of three different opioid-based immobilisation combinations in blesbok (Damaliscus pygargus phillipsi).

African wildlife species are increasingly being immobilised with combinations of a low dose of potent opioids combined with medetomidine and azaperone. The physiological effects of these combinations in comparison to conventional potent opioidazaperone combinations have scarcely been evaluated. In this cross-over study conducted on eight captive blesbok, we compared the physiological variables of blesbok immobilised with 2 mg of thiafentanil + 10 mg of azaperone (TA); 0.5 mg thiafentanil + 1.5 mg medetomidine (TM), and 0.5 mg thiafentanil + 1.5. mg medetomidine + 10 mg azaperone (TMA). Thiafentanil's effects were antagonised with naltrexone at 10 mg naltrexone per mg thiafentanil, and the medetomidine effects with atipamezole at 5 mg atipamezole per mg medetomidine. The physiological variables were compared between treatment groups using descriptive statistics and repeated measures ANOVA. The TA combination resulted in the shortest induction and recovery times, higher heart rates, respiratory rates, PaO2, SpO2, and lower MAP and A-a gradients, but with less muscle relaxation. The TM and TMA combinations caused marked bradycardia and hypoxaemia. The hypoxaemia was most severe in animals immobilised with TMA, and four of eight blesbok immobilised had a PaO2 < 35 mmHg at the 10- or 15-minute sampling point. These blesbok were provided supplementary oxygen, which corrected the hypoxaemia. The TA combinations caused the lowest degree of physiological compromise. All three combinations were effective for the immobilisation of blesbok, but as the low-dose thiafentanil and high-dose medetomidine combinations caused marked hypoxaemia, supplementary oxygen is recommended when using these combinations.

A comparison of immobilisation quality and cardiorespiratory effects of etorphine-azaperone versus etorphine-midazolam combinations in blesbok.

ABSTRACT: The study compared immobilisation of blesbok (Damaliscus pygargus phillipsi) with etorphine and azaperone vs etorphine and midazolam. Twelve female blesbok, weighing 59.4 ± 2.8 kg, were used. Each animal randomly received Treatment 1 (T1) (etorphine, 0.07 ± 0.003 mg/kg + azaperone, 0.36 ± 0.02 mg/kg) and Treatment 2 (T2) (etorphine, 0.07 ± 0.003 mg/kg + midazolam, 0.20 ± 0.01 mg/kg) with a one-week washout period between treatments. Induction times were recorded followed by physiological monitoring for 45 minutes of immobilisation. Immobilisation was reversed with naltrexone (20 mg per mg etorphine). Recovery times were also recorded. Induction, immobilisation and recovery were scored with subjective measures. Inductions and recoveries did not differ between combinations, but the quality of immobilisation was significantly better with T1. Rectal temperature and blood pressure were significantly lower during T1. Both treatments resulted in severe hypoxaemia and impaired gas exchange, although overall hypoxaemia was more pronounced for T1. Animals treated with T2, however, exhibited a deterioration in respiration as the monitoring period progressed, possibly as a result of impaired ventilatory muscle function due to the effects of midazolam. Both combinations are suitable for adequate immobilisation of blesbok and should be selected based on the specific capture situation. Supplementation with oxygen is highly recommended.

Meat quality of kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus): The effect of gender and age on the fatty acid profile, cholesterol content and sensory characteristics of kudu and impala meat.

Game meat has distinct sensory characteristics and favourable fatty acid profiles which differ between species. The SFA's percentage was found to be higher in impala meat (51.12%) than kudu meat (34.87%) whilst the total PUFA was higher in kudu (38.88%) than impala (34.06%). Stearic acid (22.67%) was the major fatty acid in impala and oleic acid in kudu (24.35). Linoleic acid, C20:3n-6 and C22:6n-3 were higher in kudu while C20:4n-6, C20:5n-3 and C22:5n-3 were higher in impala. The PUFA:SFA ratio for kudu (1.22) was higher than for impala (0.73) while impala had a higher n-6 PUFA's to n-3 PUFA ratio (3.76) than kudu (2.20). Kudu was higher in cholesterol (71.42±2.61mg/100gmuscle) than impala (52.54±2.73mg/100gmuscle). Sensory evaluation showed impala had a more intense game aroma and flavour while the initial juiciness of cooked samples of kudu was higher. The results show kudu and impala can be marketed for their unique flavours and aromas as well as being a healthy substitute for other red meats.

Meat quality of kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus): Carcass yield, physical quality and chemical composition of kudu and impala Longissimus dorsi muscle as affected by gender and age.

The meat quality of kudu and impala was compared. Live weight and carcass weight differed between species, genders and age groups. Impala had the highest dressing percentage while kudu had the highest live weight and carcass weight. Kudu had the lowest fat content while female animals had a higher fat and myoglobin content than males. Sub-adults had a higher ash content than adults. Species, gender and age had no effect of pH, drip loss, cooking loss or tenderness although kudu had higher L∗, a∗, b∗ and chroma values than impala. Impala sub-adults had significantly higher insoluble collagen, soluble collagen, total collagen and hydroxyproline content than kudu sub-adults. Kudu had the highest potassium levels while impala had the highest phosphorus levels. Potassium, sodium, iron and copper levels also differed between species.

Nutritional value of cooked offal derived from free-range rams reared in South Africa.

Nutritional value of Dorper (n=10) and Merino (n=10) by-products were evaluated. Proximate composition differed between organs and breeds with Merino heart (68.9 g/100 g), spleen (77.2 g/100 g) and testicles (83.7 g/100 g) having higher moisture contents than their Dorper counterparts. Dorper brain (10.1 g/100 g), heart (15.2 g/100 g), spleen (20.4 g/100 g) and testicles (12.9 g/100 g) had higher protein contents than Merino. Dorper organs also tended to have a lower fat content. Amino acid and fatty acid profiles differed between organs and breeds. Few differences were noted in total SFA and MUFA. Dorper heart (1.8%) had significantly lower total PUFA than Merino heart (7.3%). All the organs showed favourable P:S ratios, with the exception of the tongue, heart and stomach. Dorper and Merino brain, lungs and testicles had favourable n-6/n-3 ratios. Cholesterol content differed between both organs and breeds. The value of offal as food is discussed further.

A comparison between the effects of day and night cropping on gemsbok (Oryx gazella) meat quality.

This study compares the effects of day- and night cropping on the quality of gemsbok meat. Day-cropped animals had higher behavioural scores and cortisol levels (behavioural score: 3.5+/-0.423; cortisol: 136.88+/-2.731nmol/L) than night-cropped animals (behavioural score: 2.1+/-0.378; cortisol: 64.1+/-1.633nmol/L) while night-cropped animals had a higher mean pH(u) (5.54+/-0.013) than day-cropped animals (5.49+/-0.014). The exponential decay model, y=a+b(-)(ct), fitted to the pH data indicated a difference in constant a only (day=5.45+/-0.006; night=5.51+/-0.006). Night-cropped animals produced meat that was darker in colour. The results indicate that day cropping may have elicited more ante-mortem stress although this did not necessarily affect the meat quality adversely, however due to the limitation of sample size, the data may be skewed by outliers and should thus be interpreted with caution.