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F. H. Bank - One of the best experts on this subject based on the ideXlab platform.
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allozyme divergence among four representatives of the subfamily alcelaphinae family bovidae
Comparative Biochemistry and Physiology B, 1995Co-Authors: J P Grobler, F. H. BankAbstract:Abstract We used protein gel electrophoresis to study genetic diversity within and between blue wildebeest ( Connochaetes taurinus ), black wildebeest ( C. gnou ), red hartebeest ( Alcelaphus buselaphus caama ) and blesbok ( Damaliscus dorcas phillipsi ). Twenty-nine protein encoding loci were resolved, average heterozygosity ranged from 3.25-5.36% and between population gene diversity accounted for the major share of the total relative gene diversity (69.34%). Genetic distance values ranged from 0.021 to 0.132 and 0.029 to 0.136, with closest identity between the two wildebeest species (as expected for congeneric species). The results are discussed with specific reference to taxonomic relationships between species within the subfamily where interbreeding is known to have occurred.
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genetic variability in south african blue wildebeest Connochaetes taurinus
Comparative Biochemistry and Physiology B, 1993Co-Authors: J P Grobler, F. H. BankAbstract:Abstract 1. 1. We used protein gel-electrophoresis to investigate genetic heterogeneity at 33 protein coding loci in a total of 46 blue wildebeest ( C. taurinus ) kept under different management regimes. 2. 2. Average heterozygosity ranged from 2.14 to 4.3% and within-population differences accounted for 97.2% of total relative gene diversity. 3. 3. Comparatively little divergence was found between animals sampled from populations with very diverse population sizes and management histories, with the largest genetic distance estimated between any two populations being only 0.0021. 4. 4. We discuss our results with particular emphasis on the influence of management history on genetic diversity and divergence in C. taurinus .
L C Hoffman - One of the best experts on this subject based on the ideXlab platform.
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preservation of previously frozen black wildebeest meat Connochaetes gnou using oregano oreganum vulgare essential oil
Meat Science, 2019Co-Authors: Nompumelelo Shange, L C Hoffman, Thandeka N Makasi, Pieter A GouwsAbstract:Abstract The effect of oregano essential oil (1% v/v) on the shelf-life of black wildebeest Biceps femoris (BF) muscles stored aerobically at 2.6 ± 0.6 °C was investigated by evaluating changes in pH, lipid oxidation, microbial counts and colour over 9 days of storage. Treatment group had lower pH values than control group, for most of storage. Lipid oxidation was stabilized at 1.4-fold slower in the treatment group. No overall improvements were seen in colour parameters, however b* values significantly decreased in the treatment group, whilst b* values from the control group did not experience any changes during storage.
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the effect of a slow release formulation of zuclopenthixol acetate acunil on captive blue wildebeest Connochaetes taurinus behavior and physiological response
Journal of Zoo and Wildlife Medicine, 2016Co-Authors: Liesel L Laubscher, L C Hoffman, Neville Pitts, Jacobus P RaathAbstract:Abstract The study investigated the effect of a slow-release formulation of zuclopenthixol acetate (Acunil®) on blue wildebeest (Connochaetes taurinus) in captivity. Two groups of trials were conducted using either Acunil or a placebo (control). Animals (Acunil: n = 17; placebo: n = 12) were observed for a 12-hr period before the administration of Acunil or the placebo (pretreatment). After 24 hr, animals were administered Acunil (1.5 mg/kg) or a placebo (1.0–3.0 ml of sterile water) and observed again for 12 hr (posttreatment). During both treatments, animals were stimulated every 2 hr for 1 min by a person entering the enclosure (referred to as periods of stimulation). Behavioral observations and continuous heart rate, respiration rate, and motion measurements were taken throughout. Animals treated with Acunil spent more time lying with their heads folded back, eating and standing with their heads down, and less time being vigilant and exploring while walking around. Animals treated with the placebo als...
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validating a human biotelemetry system for use in captive blue wildebeest Connochaetes taurinus
Zoo Biology, 2015Co-Authors: Liesel L Laubscher, L C Hoffman, Neville Pitts, Jacobus P RaathAbstract:We fitted two blue wildebeest (Connochaetes taurinus) with modified versions of the Equivital TM EQ02 wireless monitoring system to evaluate if the device could accurately measure heart rate and respiration rate in this species whilst anaesthetized as well as whilst fully conscious in captivity.Whilst under anaesthesia,we monitoredeach animal’s heart rate andrespiration rate using the Equivital TM biotelemetry belt, a Cardell 1 veterinary monitor and manual measurements. The animals were also administered doxapram hydrochloride (Dopram 1 ) and adrenaline intravenously at different times to stimulate changes in respiration andheart rate, respectively. Once 30 minutes of monitoring was completed, we reversed the anaesthetic and left the animalsincaptivityfor24hourswhilstwearingtheEquivital TM belts.After24hr,werepeatedtheanaesthesiaandmonitoringas well as the administration of the doxapram hydrochloride and adrenaline. Intraclass Correlation Coefficients (ICC) calculated between all three monitoring methods showed moderate to excellent agreements for heart rate on both days (ICC: 0.73–0.98). ICCs calculated between the three methods for respiration rate showed good to excellent agreement between the Equivital belt and the other two methods (0.82–0.92) with the exception of occasions when only poor to fair agreements were foundbetween the Cardell 1 measurements and manual measurements. Heart rate and respiration rate were also found to increase with motion while animals were in captivity. The results indicate that a modified version of the Equivital TM EQ02 system can be used as a potential biotelemetry device for measuring heart and respiration rate in captive blue wildebeest. Zoo Biol. XX:XX–XX, 2015. © 2015 Wiley Periodicals, Inc.
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quality characteristics of blue wildebeest Connochaetes taurinus meat
South African Journal of Wildlife Research, 2011Co-Authors: L C Hoffman, S J Van Schalkwyk, Michael MullerAbstract:The Muscularis longissimus dorsi of eight blue wildebeest (Connochaetus taurinus), collected at Sandveld Nature Reserve, South Africa, were analysed for biochemical and physical characteristics and chemical composition. The initial (6.60) and final (5.41) pH, drip loss (4.91%), cooking loss (39.42%) and maximum Warner-Bratzler shear force (4.91 kg/ 1.27 cmo) were comparable to values found in meat from several other African game species (black wildebeest, blesbok, duiker, impala, red hartebeest, reedbuck, springbok, warthog). Like other wild ungulates, blue wildebeest meat had a higher crude protein (22.28%) and lower lipid (1.06%) content compared to beef, which makes it a healthy alternative to traditional red meat.
Shane K Maloney - One of the best experts on this subject based on the ideXlab platform.
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orientation to solar radiation in black wildebeest Connochaetes gnou
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005Co-Authors: Graeme Moss, Shane K Maloney, Duncan MitchellAbstract:We recorded the body axis orientation of free-living black wildebeest relative to incident solar radiation and wind. Observations were made on three consecutive days, on six occasions over the course of 1 year, in a treeless, predominantly cloudless habitat. Frequency of orientation parallel to incident solar radiation increased, and perpendicular to incident solar radiation decreased, as ambient dry-bulb temperature or solar radiation intensity increased, or wind speed decreased. We believe these changes were mediated via their effect on skin temperature. Parallel orientation behavior was more prominent when the wildebeest were standing without feeding than it was when they were feeding. We calculate that a black wildebeest adopting parallel orientation throughout the diurnal period would absorb 30% less radiant heat than the same animal adopting perpendicular orientation. Parallel orientation was reduced at times when water was freely available, possibly reflecting a shift from behavioral to autonomic thermoregulatory mechanisms. The use of orientation behavior by black wildebeest is well developed and forms part of the suite of adaptations that help them to maintain heat balance while living in a shadeless, often hot, environment.
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alteration in diel activity patterns as a thermoregulatory strategy in black wildebeest Connochaetes gnou
Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology, 2005Co-Authors: Graeme Moss, Shane K Maloney, Tammy Cartmell, Duncan MitchellAbstract:The nychthemeral activity patterns of a population of female black wildebeest inhabiting a shadeless environment were surveyed periodically over 1 year. The wildebeest fed mostly at night, with the proportion of feeding at night increasing when ambient conditions were hotter. Inactive periods were spent mostly lying during cooler weather but standing as days became hotter. We suggest that the entire suite of behavioural adjustments is beneficial to heat exchange with the environment. Behaviour patterns were markedly different during one warm weather survey, from the other warm weather surveys, when an 8-month dry spell had just been broken. We suggest that this may reflect the availability of water for autonomic thermoregulation, a consequent decreased reliance on behavioural thermoregulation, and a release of the thermal constraints on foraging. Our results help to explain the ability of black wildebeest to maintain body core temperature within a very narrow range despite being exposed to an environment with large nychthemeral variations in thermal conditions and offering little in the way of microclimate selection.
Paul J. Bartels - One of the best experts on this subject based on the ideXlab platform.
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211 QUALITY CHANGES IN BLUE WILDEBEEST (Connochaetes TAURINUS) EPIDIDYMAL SPERMATOZOA MAINTAINED AT 4°C
Reproduction Fertility and Development, 2004Co-Authors: F. Olivier, T. Spies, Felipe Martínez-pastor, D.m. Barry, Paul J. BartelsAbstract:Wildlife management in southern Africa often involves the harvesting of animals on ranches and reserves, providing unique opportunities to collect and assess the quality of epididymal spermatozoa for possible future conservation actions. The black wildebeest (Connochaetes gnu) is facing renewed threats to its survival, including the production of fertile hybrids from crossing with the more common blue wildebeest (Connochaetes taurinus). The close relationship between the two wildebeest species allows for the blue wildebeest to be used as a model to assess epididymal sperm quality over time while maintained at 4°C. Field conditions often preclude the immediate availability of liquid nitrogen, necessitating the development of alternative short-term storage methods. All chemicals were provided by Sigma (South Africa) unless otherwise stated. Testes were harvested from 6 blue wildebeest bulls at a local game farm, Savannah, and kept at 5°C during transportation to the lab. Epididymides were dissected out and spermatozoa were flushed out of the cauda epididymis using 1 mL of Tris-citrate egg yolk extender (Fraction A, Biladyl, Minitub, Germany), followed by storage at 4°C and assessment at 12 h intervals. At each interval, an aliquot was removed, washed with a modified buffered HEPES solution (20 mM HEPES, 355 mM sucrose, 10 mM glucose, 2.5 mM KOH;; 400 mOsm/kg, pH 7; Sigma) and visually assessed with a phase contrast microscope (×200, at 37°C) to determine the percentage of motile (MS) and progressive motile (PS) spermatozoa. In addition, plasma membrane integrity (PMI) was assessed with eosin-nigrosin staining and active mitochondrial status (MIT) assessed with an epifluorescent microscope (×400) using the fluorescent probe JC-1 (Molecular Probes, The Netherlands;; 7.5 μM; 30 min at 37°C). Resilience to hypo-osmotic shock was also evaluated by incubating the sample in a modified hypo-osmotic medium (100 mOsm kg−1; 15 min RT), and staining with PI to assess plasma membrane integrity (HOSPMI). A summary of results is presented in the table 1. The MS, MIT and HOSPMI did not decrease significantly during the 48 h storage period. The only parameters that showed a significant decrease were PS and PMI (P
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211 quality changes in blue wildebeest Connochaetes taurinus epididymal spermatozoa maintained at 4 c
Reproduction Fertility and Development, 2004Co-Authors: F. Olivier, F Martinezpastor, T. Spies, D.m. Barry, Paul J. BartelsAbstract:Wildlife management in southern Africa often involves the harvesting of animals on ranches and reserves, providing unique opportunities to collect and assess the quality of epididymal spermatozoa for possible future conservation actions. The black wildebeest (Connochaetes gnu) is facing renewed threats to its survival, including the production of fertile hybrids from crossing with the more common blue wildebeest (Connochaetes taurinus). The close relationship between the two wildebeest species allows for the blue wildebeest to be used as a model to assess epididymal sperm quality over time while maintained at 4°C. Field conditions often preclude the immediate availability of liquid nitrogen, necessitating the development of alternative short-term storage methods. All chemicals were provided by Sigma (South Africa) unless otherwise stated. Testes were harvested from 6 blue wildebeest bulls at a local game farm, Savannah, and kept at 5°C during transportation to the lab. Epididymides were dissected out and spermatozoa were flushed out of the cauda epididymis using 1 mL of Tris-citrate egg yolk extender (Fraction A, Biladyl, Minitub, Germany), followed by storage at 4°C and assessment at 12 h intervals. At each interval, an aliquot was removed, washed with a modified buffered HEPES solution (20 mM HEPES, 355 mM sucrose, 10 mM glucose, 2.5 mM KOH;; 400 mOsm/kg, pH 7; Sigma) and visually assessed with a phase contrast microscope (×200, at 37°C) to determine the percentage of motile (MS) and progressive motile (PS) spermatozoa. In addition, plasma membrane integrity (PMI) was assessed with eosin-nigrosin staining and active mitochondrial status (MIT) assessed with an epifluorescent microscope (×400) using the fluorescent probe JC-1 (Molecular Probes, The Netherlands;; 7.5 μM; 30 min at 37°C). Resilience to hypo-osmotic shock was also evaluated by incubating the sample in a modified hypo-osmotic medium (100 mOsm kg−1; 15 min RT), and staining with PI to assess plasma membrane integrity (HOSPMI). A summary of results is presented in the table 1. The MS, MIT and HOSPMI did not decrease significantly during the 48 h storage period. The only parameters that showed a significant decrease were PS and PMI (P < 0.01, Kruskall-Wallis test). However, PMI showed a slow but steady decrease (13%), whereas PS underwent a significant drop (52%). In conclusion, epididymal spermatozoa from the blue wildebeest, kept at 4°C for 48 h, may still be useful for some assisted-reproduction techniques. The use of spermatozoa from a common but closely related wildebeest species allows for the development of assisted-reproduction techniques that may one day aid the conservation of threatened wildebeest species. Additional research is needed to confirm these findings and to test the effect of longer storage times on spermatozoa of this species as well as closely related endangered species. Table 1 Parameters measured during the 12-h time periods (mean ± SD)
F Martinezpastor - One of the best experts on this subject based on the ideXlab platform.
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160 freezability of electroejaculated and epididymal spermatozoa from blue wildebeest Connochaetes taurinus
Reproduction Fertility and Development, 2009Co-Authors: M Matacampuzano, M Alvarez, S Borragan, F Martinezpastor, M Nicolas, J Tamayo, L AnelAbstract:Maintenance of population viability, especially endangered species, requires preservation of as much genetic variability as possible, therefore genetic resource banks are very important. For male gametes, preservation of all available sources (ejaculates and epididymal) are useful. Information regarding sperm characteristics of most wild ruminant species is limited compared to that from domestic species. The objective of this work was to characterize the freezability of electroejaculated and epididymal spermatozoa from a wildebeest (5 year old; housed in Cabarceno Nature Park, Cantabria, Spain) that was castrated because of behavioral problems. After general anesthesia (ethorfine + xilazine, 1.8 mL + 0.5 mg kg–1) with dart, semen was collected by electroejaculation (3 V and 75 mA). Sperm concentration was 250 × 106 mL–1 (total spermatozoa: 1128.6 × 106). After castration, epididymides were disected and spermatozoa were collected by making several incisions in the caudal epididymis. Concentration was 12 441 × 106 spermatozoa mL–1 (total spermatozoa: 24 882 × 106). Samples were diluted to 200 × 106 spermatozoa mL–1 (TesT-Fructose-Egg yolk-Glycerol-Antibiotics) and chilled to 5°C during 2 h. Diluted semen was packaged in 0.25-mL straws and frozen from 5°C to –100°C (–20°C min–1) in a programmable cell freezer (Kryo 10, Planer). Straws were plunged into liquid nitrogen until analysis and thawed in a water bath (65°C, 6 s). Fresh, pre-freezing and post-thawed samples were analysed for motility (total motility TM, %; progressive motility PM, %; path velocity VAP, μm s–1; track speed VCL, μm s–1; progressive velocity VSL, μm s–1) using a CASA (ISAS, Proiser, Valencia, Spain). Viability (VIAB %) (SYBR-14 and propidium iodide) and mitochondrial membrane potential (MIT %) (JC1) were assessed by flow cytometry. Post-thawing results for electroejaculated v. epididymal samples were, respectively: TM: 87.0 v. 64.6%; PM: 68.7 v. 33.4%; VAP: 95.9 v. 49.8 μm s–1; VCL: 108.3 v. 71.6 μm s–1; VSL: 86.7 v. 40.2 μm s–1; VIAB: 57.0 v. 73.9%; MIT: 59.5 v. 77.5%. Motility parameters were higher for the electroejaculated sample; however, viability was higher for the epididymal sample. Recovery rates (post-thawed value/pre-freezing value × 100) for electroejaculated v. epididymal samples were: TM: 97.2 v. 93.4%; PM: 113.3 v. 103.2%; VAP: 88.9 v. 122.0 μm s–1; VCL: 87.5 v. 126.0 μm s–1; VSL: 93.4 v. 125.3 μm s–1; VIAB: 75.0 v. 97.7%; MIT: 69.2 v. 95.9%). These rates suggest a good freezability of electroejaculated and epididymal spermatozoa in blue wildebeest. This work was supported in part by Cantur. 3 Supported by Juan de la Cierva program (MICINN, Spain).
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211 quality changes in blue wildebeest Connochaetes taurinus epididymal spermatozoa maintained at 4 c
Reproduction Fertility and Development, 2004Co-Authors: F. Olivier, F Martinezpastor, T. Spies, D.m. Barry, Paul J. BartelsAbstract:Wildlife management in southern Africa often involves the harvesting of animals on ranches and reserves, providing unique opportunities to collect and assess the quality of epididymal spermatozoa for possible future conservation actions. The black wildebeest (Connochaetes gnu) is facing renewed threats to its survival, including the production of fertile hybrids from crossing with the more common blue wildebeest (Connochaetes taurinus). The close relationship between the two wildebeest species allows for the blue wildebeest to be used as a model to assess epididymal sperm quality over time while maintained at 4°C. Field conditions often preclude the immediate availability of liquid nitrogen, necessitating the development of alternative short-term storage methods. All chemicals were provided by Sigma (South Africa) unless otherwise stated. Testes were harvested from 6 blue wildebeest bulls at a local game farm, Savannah, and kept at 5°C during transportation to the lab. Epididymides were dissected out and spermatozoa were flushed out of the cauda epididymis using 1 mL of Tris-citrate egg yolk extender (Fraction A, Biladyl, Minitub, Germany), followed by storage at 4°C and assessment at 12 h intervals. At each interval, an aliquot was removed, washed with a modified buffered HEPES solution (20 mM HEPES, 355 mM sucrose, 10 mM glucose, 2.5 mM KOH;; 400 mOsm/kg, pH 7; Sigma) and visually assessed with a phase contrast microscope (×200, at 37°C) to determine the percentage of motile (MS) and progressive motile (PS) spermatozoa. In addition, plasma membrane integrity (PMI) was assessed with eosin-nigrosin staining and active mitochondrial status (MIT) assessed with an epifluorescent microscope (×400) using the fluorescent probe JC-1 (Molecular Probes, The Netherlands;; 7.5 μM; 30 min at 37°C). Resilience to hypo-osmotic shock was also evaluated by incubating the sample in a modified hypo-osmotic medium (100 mOsm kg−1; 15 min RT), and staining with PI to assess plasma membrane integrity (HOSPMI). A summary of results is presented in the table 1. The MS, MIT and HOSPMI did not decrease significantly during the 48 h storage period. The only parameters that showed a significant decrease were PS and PMI (P < 0.01, Kruskall-Wallis test). However, PMI showed a slow but steady decrease (13%), whereas PS underwent a significant drop (52%). In conclusion, epididymal spermatozoa from the blue wildebeest, kept at 4°C for 48 h, may still be useful for some assisted-reproduction techniques. The use of spermatozoa from a common but closely related wildebeest species allows for the development of assisted-reproduction techniques that may one day aid the conservation of threatened wildebeest species. Additional research is needed to confirm these findings and to test the effect of longer storage times on spermatozoa of this species as well as closely related endangered species. Table 1 Parameters measured during the 12-h time periods (mean ± SD)