A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potenti... more A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potentially be used to assist reproduction in endangered equid species. The objectives of this study were to evaluate a specific transvaginal ultrasound-guided oocyte recovery procedure for use in zebra mares and the general applicability of IVF procedures in zebra. Ovaries were collected from Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae) mares at routine culling for Expt. I. Of the 144 oocytes recovered from these ovaries, 70% were of excellent quality. No significant difference in oocyte quality was found between the two zebra species. Zona drilling was performed on in vitro-matured oocytes prior to IVF. Epididymal sperm from culled Burchell's zebra stallions were used for IVF. The sperm either were exposed to calcium ionophore or were not treated and served as a control. In vitro fertilized oocytes were then co-cultured with zebra granulosa cell...
We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of buffalo (Sy... more We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of buffalo (Syncerus caffer), elephant (Loxodonta africana), kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. We used linear mixed models to analyse the effect of year, area and age on the trophy size, quota size and offtake levels. One sample t-test was used to compare observed trophy size with Safari Club International (SCI) minimum score. Trophy sizes for buffalo and elephant were below the SCI minimum score. Kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015.Age at harvest for buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of elephant and kudu declined whilst the quota size did not change in the same period. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004-2015. The trophy size and harvesting patterns in some species pose a conservation and management dilemma on the sustainability of trophy hunting. We recommend: (1) temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, (2) introduction of variable trophy fee pricing system based on trophy size.
With an increased need for genetic diversity within populations, assisted reproductive technology... more With an increased need for genetic diversity within populations, assisted reproductive technology is becoming an important tool for banking semen and embryos, with the possibility of future AI or embryo transfer between distant populations. Previous research has demonstrated that the broad approach of applying bovine IVM/F/C protocols to African antelope is inefficient for embryo production. The purpose of this study was to determine the timing of oocyte maturation (to telophase or metaphase II) in vitro in springbok (Antidorcas marsupialis; n=84), black wildebeest (Connechaetes gnu; n=18), blesbok (Damaliscus dorcus phillipsi; n=9), and reedbuck (Redunca arundinum; n=1). Ovaries were collected within 4h of death from culled animals on game reserves in South Africa, placed into warm SOF-HEPES, sliced and cumulus-oocyte complexes (COCs) collected. Complexes were placed into GMat medium supplemented with 0.01UmL−1 each FSH and LH, 50ngmL−1 EGF, and 1.0% (v/v) PSA (100U penicillin mL−1...
Cloning technology has the potential to stimulate the development of the animal biotechnology ind... more Cloning technology has the potential to stimulate the development of the animal biotechnology industry in southern Africa, as well as provide conservationists with an additional tool to possibly assist with conserving critically endangered wildlife species sometime in the future. The aim of this study was to determine whether cloning could produce blastocysts and possibly live progeny in a field-type laboratory without micromanipulators and CO2 incubator. Approx. 1×1-cm ear skin notches were surgically removed from a physically immobilized 9-year-old Holstein cow, a former South African milk production record holder. The tissues were placed into physiological saline and transported to the laboratory at 4°C within 2h, cleaned with chlorohexidine gluconate and sliced finely in Minimal Essential Medium supplemented with 10% fetal calf serum. The resultant tissue explants were treated as previously described (Bartels et al., 2003 Theriogenology 59, 387) and actively growing fibroblast c...
Joint Conference of the European, Middle Eastern & African Society for Biopreservation & ... more Joint Conference of the European, Middle Eastern & African Society for Biopreservation & Biobanking (ESBB) and the Spanish National Biobank Network Granada, Spain
Wildlife management in southern Africa often involves the harvesting of animals on ranches and re... more 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 ...
Biological Resource Banks represent a potentially valuable tool for species conservation. It is, ... more Biological Resource Banks represent a potentially valuable tool for species conservation. It is, however, necessary to understand the species-specific cryopreservation process and its consequences for spermatozoa to aid in the development of assisted reproduction as a future conservation tool. The aim of this study was to assess the in vitro functionality of white rhinoceros Cerathoterium simum epididymal spermatozoa both before and after cryopreservation. Testes from a harvested white rhino bull were removed and transported at 5°C to the laboratory within 4h. The cauda epididymis was dissected out and flushed with 2mL of Tris-citrate egg yolk extender (fraction A, Biladyl, Minitüb, Germany). A 0.1mL aliquot was removed for analysis and the balance (9mL; 2mL fraction A+7mL sperm sample) mixed with an additional 27.2mL of Tris-citrate egg yolk with glycerol (fraction B, Bidadyl). The extended sample was allowed to cool to 4°C over a 6-h period before an additional 29.2mL of cooled fr...
Wildlife conservation requires traditional as well as innovative conservation strategies in order... more Wildlife conservation requires traditional as well as innovative conservation strategies in order to preserve gene and species diversity. Interspecies nuclear transfer has the potential to conserve genes from critically endangered wildlife species where few or no oocytes are available from the endangered species, and where representative cell lines have been established for the wildlife population while numbers were still abundant. The purpose of this study was to investigate the developmental ability of embryos reconstructed with transfer of somatic cells from the African buffalo (Syncerus caffer), bontebok (Damaliscus dorcus dorcus) and eland (Taurotragus oryx) to enucleated domestic cattle (Bos taurus) oocytes. Skin tissue from the three wildlife species were collected by surgically removing approx. 1.0×1.0cm ear skin notches from animals immobilized with a combination of etorphine hydrochloride (M99; South Africa) and azaperone (Stressnil, South Africa). The biopsies were placed...
Postmortem recovery of epididymal spermatozoa and their preservation in Biological Resource Banks... more Postmortem recovery of epididymal spermatozoa and their preservation in Biological Resource Banks is a convenient source of germplasm, providing a possible future conservation resource for selected endangered wildlife species. It is necessary to gain knowledge of the biology of the gametes of the different species, in order to define effective protocols for cryopreservation and future assisted reproductive technology application. A pilot study on the changes in blue wildebeest (Connochaetes taurinus) and blesbok (Damaliscus dorcas phillipsi) epididymal sperm was carried out in order to provide some insight into the effects of incubation at 37°C. Chemicals were aquired from Sigma (South Africa), except JC-1 (Molecular Probes, Leiden, The Netherlands). Sperm was obtained by flushing the vas deferens and cauda epididymis of 6 adult blue wildebeests and 4 adult blesbok after the breeding season using 1 mL of Biladyl (fraction A; Minitüb, Tiefenbach, Germany). Cells were washed and resus...
The availability of gametes from the cropping of excess wildlife species provides the opportunity... more The availability of gametes from the cropping of excess wildlife species provides the opportunity for the advancement of knowledge into assisted reproductive technology for possible future conservation measures. Little is known about the longevity of springbok (Antidorcas marsupialis) spermatozoa maintained in fertilization medium. The aim of this project was to determine the quality changes of post-thawed springbok spermatozoa incubated in fertilization medium by measuring plasma membrane integrity over time. Testes (n = 12) were obtained from two geographically distinct free-ranging springbok populations in South Africa. Spermatozoa were flushed from the cauda epididymides within three hours of the animals' death. Samples from an individual male were pooled, diluted to 400 × 106 sperm/mL with Biladyl (Minitüb, Tiefenbach, Germany) fraction A (no glycerol) and equilibrated in a water bath for 6 h at 4°C. An equal volume of Biladyl fraction B (containing 12% glycerol) was added ...
Long term monitoring of population estimates and trophy size trends is requisite to ensure that t... more Long term monitoring of population estimates and trophy size trends is requisite to ensure that trophy hunting is sustainable. We explored the influence of trophy hunting on population size and trophy quality of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) antelopes from 1997 to 2014 in Cawston Ranch, Zimbabwe. Population estimates of the three species showed a cyclical declining trend, albeit being statistically insignificant for the three species. Hunting pressure had no significant effect on the population estimates of the three species for the period 1997-2014. Impala population declined (-30 %) between 2003 and 2008 possibly due to increased illegal hunting pressure associated with land invasions during this period. Trophy size of all species declined over time, 2004-2014, (impala (-1.3 %), kudu (-3.9 %), sable (-2.6 %) possibly due diet quality and loss of genetic variability in these populations. However, trophy size for g...
Joint Conference of the European, Middle Eastern & African Society for Biopreservation & ... more Joint Conference of the European, Middle Eastern & African Society for Biopreservation & Biobanking (ESBB) and the Spanish National Biobank Network Granada, Spain
A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potenti... more A noninvasive repeatable method to harvest oocytes for in vitro fertilization (IVF) could potentially be used to assist reproduction in endangered equid species. The objectives of this study were to evaluate a specific transvaginal ultrasound-guided oocyte recovery procedure for use in zebra mares and the general applicability of IVF procedures in zebra. Ovaries were collected from Burchell's zebra (Equus burchelli) and Hartmann's zebra (Equus zebra hartmannae) mares at routine culling for Expt. I. Of the 144 oocytes recovered from these ovaries, 70% were of excellent quality. No significant difference in oocyte quality was found between the two zebra species. Zona drilling was performed on in vitro-matured oocytes prior to IVF. Epididymal sperm from culled Burchell's zebra stallions were used for IVF. The sperm either were exposed to calcium ionophore or were not treated and served as a control. In vitro fertilized oocytes were then co-cultured with zebra granulosa cell...
We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of buffalo (Sy... more We explored the trophy quality and trends in harvesting patterns (i.e., 2004-2015) of buffalo (Syncerus caffer), elephant (Loxodonta africana), kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) in Matetsi Safari Area, northwest Zimbabwe. We used long-term data on horn and tusk size, age, quota size allocation and offtake levels of selected species. We used linear mixed models to analyse the effect of year, area and age on the trophy size, quota size and offtake levels. One sample t-test was used to compare observed trophy size with Safari Club International (SCI) minimum score. Trophy sizes for buffalo and elephant were below the SCI minimum score. Kudu trophy sizes were within the minimum score threshold whereas sable trophy sizes were above the SCI minimum score between 2004 and 2015.Age at harvest for buffalo, kudu and sable increased whilst that of elephant remained constant between 2004 and 2015. Quota size allocated for buffalo and the corresponding offtake levels declined over time. Offtake levels of elephant and kudu declined whilst the quota size did not change in the same period. The quota size for sable increased whilst the offtake levels fluctuated without changing for the period 2004-2015. The trophy size and harvesting patterns in some species pose a conservation and management dilemma on the sustainability of trophy hunting. We recommend: (1) temporal and spatial rotational resting of hunting areas to create refuge to improve trophy quality and maintenance of genetic diversity, (2) introduction of variable trophy fee pricing system based on trophy size.
With an increased need for genetic diversity within populations, assisted reproductive technology... more With an increased need for genetic diversity within populations, assisted reproductive technology is becoming an important tool for banking semen and embryos, with the possibility of future AI or embryo transfer between distant populations. Previous research has demonstrated that the broad approach of applying bovine IVM/F/C protocols to African antelope is inefficient for embryo production. The purpose of this study was to determine the timing of oocyte maturation (to telophase or metaphase II) in vitro in springbok (Antidorcas marsupialis; n=84), black wildebeest (Connechaetes gnu; n=18), blesbok (Damaliscus dorcus phillipsi; n=9), and reedbuck (Redunca arundinum; n=1). Ovaries were collected within 4h of death from culled animals on game reserves in South Africa, placed into warm SOF-HEPES, sliced and cumulus-oocyte complexes (COCs) collected. Complexes were placed into GMat medium supplemented with 0.01UmL−1 each FSH and LH, 50ngmL−1 EGF, and 1.0% (v/v) PSA (100U penicillin mL−1...
Cloning technology has the potential to stimulate the development of the animal biotechnology ind... more Cloning technology has the potential to stimulate the development of the animal biotechnology industry in southern Africa, as well as provide conservationists with an additional tool to possibly assist with conserving critically endangered wildlife species sometime in the future. The aim of this study was to determine whether cloning could produce blastocysts and possibly live progeny in a field-type laboratory without micromanipulators and CO2 incubator. Approx. 1×1-cm ear skin notches were surgically removed from a physically immobilized 9-year-old Holstein cow, a former South African milk production record holder. The tissues were placed into physiological saline and transported to the laboratory at 4°C within 2h, cleaned with chlorohexidine gluconate and sliced finely in Minimal Essential Medium supplemented with 10% fetal calf serum. The resultant tissue explants were treated as previously described (Bartels et al., 2003 Theriogenology 59, 387) and actively growing fibroblast c...
Joint Conference of the European, Middle Eastern & African Society for Biopreservation & ... more Joint Conference of the European, Middle Eastern & African Society for Biopreservation & Biobanking (ESBB) and the Spanish National Biobank Network Granada, Spain
Wildlife management in southern Africa often involves the harvesting of animals on ranches and re... more 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 ...
Biological Resource Banks represent a potentially valuable tool for species conservation. It is, ... more Biological Resource Banks represent a potentially valuable tool for species conservation. It is, however, necessary to understand the species-specific cryopreservation process and its consequences for spermatozoa to aid in the development of assisted reproduction as a future conservation tool. The aim of this study was to assess the in vitro functionality of white rhinoceros Cerathoterium simum epididymal spermatozoa both before and after cryopreservation. Testes from a harvested white rhino bull were removed and transported at 5°C to the laboratory within 4h. The cauda epididymis was dissected out and flushed with 2mL of Tris-citrate egg yolk extender (fraction A, Biladyl, Minitüb, Germany). A 0.1mL aliquot was removed for analysis and the balance (9mL; 2mL fraction A+7mL sperm sample) mixed with an additional 27.2mL of Tris-citrate egg yolk with glycerol (fraction B, Bidadyl). The extended sample was allowed to cool to 4°C over a 6-h period before an additional 29.2mL of cooled fr...
Wildlife conservation requires traditional as well as innovative conservation strategies in order... more Wildlife conservation requires traditional as well as innovative conservation strategies in order to preserve gene and species diversity. Interspecies nuclear transfer has the potential to conserve genes from critically endangered wildlife species where few or no oocytes are available from the endangered species, and where representative cell lines have been established for the wildlife population while numbers were still abundant. The purpose of this study was to investigate the developmental ability of embryos reconstructed with transfer of somatic cells from the African buffalo (Syncerus caffer), bontebok (Damaliscus dorcus dorcus) and eland (Taurotragus oryx) to enucleated domestic cattle (Bos taurus) oocytes. Skin tissue from the three wildlife species were collected by surgically removing approx. 1.0×1.0cm ear skin notches from animals immobilized with a combination of etorphine hydrochloride (M99; South Africa) and azaperone (Stressnil, South Africa). The biopsies were placed...
Postmortem recovery of epididymal spermatozoa and their preservation in Biological Resource Banks... more Postmortem recovery of epididymal spermatozoa and their preservation in Biological Resource Banks is a convenient source of germplasm, providing a possible future conservation resource for selected endangered wildlife species. It is necessary to gain knowledge of the biology of the gametes of the different species, in order to define effective protocols for cryopreservation and future assisted reproductive technology application. A pilot study on the changes in blue wildebeest (Connochaetes taurinus) and blesbok (Damaliscus dorcas phillipsi) epididymal sperm was carried out in order to provide some insight into the effects of incubation at 37°C. Chemicals were aquired from Sigma (South Africa), except JC-1 (Molecular Probes, Leiden, The Netherlands). Sperm was obtained by flushing the vas deferens and cauda epididymis of 6 adult blue wildebeests and 4 adult blesbok after the breeding season using 1 mL of Biladyl (fraction A; Minitüb, Tiefenbach, Germany). Cells were washed and resus...
The availability of gametes from the cropping of excess wildlife species provides the opportunity... more The availability of gametes from the cropping of excess wildlife species provides the opportunity for the advancement of knowledge into assisted reproductive technology for possible future conservation measures. Little is known about the longevity of springbok (Antidorcas marsupialis) spermatozoa maintained in fertilization medium. The aim of this project was to determine the quality changes of post-thawed springbok spermatozoa incubated in fertilization medium by measuring plasma membrane integrity over time. Testes (n = 12) were obtained from two geographically distinct free-ranging springbok populations in South Africa. Spermatozoa were flushed from the cauda epididymides within three hours of the animals' death. Samples from an individual male were pooled, diluted to 400 × 106 sperm/mL with Biladyl (Minitüb, Tiefenbach, Germany) fraction A (no glycerol) and equilibrated in a water bath for 6 h at 4°C. An equal volume of Biladyl fraction B (containing 12% glycerol) was added ...
Long term monitoring of population estimates and trophy size trends is requisite to ensure that t... more Long term monitoring of population estimates and trophy size trends is requisite to ensure that trophy hunting is sustainable. We explored the influence of trophy hunting on population size and trophy quality of impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros) and sable (Hippotragus niger) antelopes from 1997 to 2014 in Cawston Ranch, Zimbabwe. Population estimates of the three species showed a cyclical declining trend, albeit being statistically insignificant for the three species. Hunting pressure had no significant effect on the population estimates of the three species for the period 1997-2014. Impala population declined (-30 %) between 2003 and 2008 possibly due to increased illegal hunting pressure associated with land invasions during this period. Trophy size of all species declined over time, 2004-2014, (impala (-1.3 %), kudu (-3.9 %), sable (-2.6 %) possibly due diet quality and loss of genetic variability in these populations. However, trophy size for g...
Joint Conference of the European, Middle Eastern & African Society for Biopreservation & ... more Joint Conference of the European, Middle Eastern & African Society for Biopreservation & Biobanking (ESBB) and the Spanish National Biobank Network Granada, Spain
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