Vorster L, de Bruin P R, Smuts M P, Durrant B S, de la Rey M, Herbst C, Holm D E
Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, South Africa.
Reproduction and Perinatal Centre, Faculty of Medicine and Health, University of Sydney, Australia.
J S Afr Vet Assoc. 2024 Dec;95(2):71-76. doi: 10.36303/JSAVA.623. Epub 2024 Aug 29.
Rhinoceros are currently one of the most threatened mammal species globally. Slow population growth, increased poaching and habitat destruction have led to increased conservation efforts for each species. Assisted reproductive technologies (ART) have been implemented in an attempt to aid reproductive outputs for the conservation of these endangered species. Developing species-specific ART programmes for wildlife have been challenging. Temperature control during oocyte recovery is essential for ensuring success.
This study is the first to investigate the effect of enema warming prior to trans-rectal ovum pick-up (OPU) on oocyte maturation in Southern white rhinoceros .
OPUs were performed on 20 rhinoceros cows from three different game farms in South Africa; oocytes were transported to one of two fertilisation laboratories for culture. The enema fluid was either warmed to 32 °C or not warmed prior to the OPU. Location of the farm, the different laboratories, ambient temperature, season, aspiration probe temperature, media type and enema temperature were investigated as predictor variables for oocyte maturation success.
After considering all other potential covariates, warming of the enema fluid was the only independent predictor of oocyte maturation success during this study.
Oocytes retrieved from rhinoceros cows that received an enema warmed to 32 °C were 2.3 times more likely to mature compared to oocytes from cows that received an unwarmed enema; the findings can be implemented in other rhinoceros ART programmes and in conservation efforts of other endangered mammalian species.
犀牛是目前全球最濒危的哺乳动物物种之一。种群增长缓慢、偷猎增加和栖息地破坏导致对每个物种的保护力度加大。辅助生殖技术（ART）已被应用，试图提高这些濒危物种的繁殖产量。为野生动物开发特定物种的ART计划一直具有挑战性。卵母细胞采集过程中的温度控制对于确保成功至关重要。
本研究首次调查经直肠采卵（OPU）前灌肠升温对南方白犀牛卵母细胞成熟的影响。
对来自南非三个不同狩猎场的20头犀牛母牛进行OPU；卵母细胞被运送到两个受精实验室之一进行培养。在OPU前，灌肠液要么升温至32°C，要么不升温。研究了养殖场位置、不同实验室、环境温度、季节、抽吸探头温度、培养基类型和灌肠温度作为卵母细胞成熟成功的预测变量。
在考虑所有其他潜在协变量后，灌肠液升温是本研究中卵母细胞成熟成功的唯一独立预测因素。
与接受未升温灌肠的母牛的卵母细胞相比，从接受升温至32°C灌肠的犀牛母牛采集的卵母细胞成熟的可能性高2.3倍；这些发现可应用于其他犀牛ART计划以及其他濒危哺乳动物物种的保护工作。
