Laboratory On Animal Germplasm Conservation, Universidade Federal Rural Do Semi-Árido-UFERSA, BR 110, Km 47, Costa and Silva, Mossoró, RN, 59625-900, Brazil.
Laboratory of Biometeorology and Environmental Biophysics, Universidade Federal Rural Do Semi-Árido-UFERSA, Mossoró, RN, Brazil.
Environ Sci Pollut Res Int. 2024 Aug;31(39):52501-52510. doi: 10.1007/s11356-024-34717-5. Epub 2024 Aug 16.
For the development of efficient management and conservation strategies for wild rodent species, understanding the aspects related to their reproduction, including the interaction of this physiological function with the environment, is essential. This study aimed to evaluate the impacts of weather changes derived from a semiarid region's dry and rainy seasons on the epididymal sperm characteristics of red-rumped agouti (Dasyprocta leporina), a histricognath rodent, still little studied, which inhabits the Brazilian Caatinga. The sperm from the epididymal cauda of 14 agoutis were collected, seven individuals per season (dry and rainy). Samples were evaluated for kinetic parameters, membrane structural and functional integrity, mitochondrial activity, morphology, and morphometry. The environmental variables were measured: maximum air temperature, relative humidity, wind speed, solar radiation, and the total rainfall for dry and rainy seasons were, respectively, 36.2 and 34.1 °C, 66.8 and 80.1%, 4.0 and 1.9 m/s, 527.3 and 441.8 W/m, and 0.2 and 517.7 mm. There were strong correlations between some sperm parameters and environmental variables, mainly those related to the acquisition of sperm mobility. Sperm concentration and the number of sperm collected were higher in the dry (1028.7 sperm/mL × 10⁶ and 1361.2 × 10 sperm) than in the rainy season (758.9 sperm × 10⁶/mL and 714.6 sperm × 10). During the rainy season, there were fewer sperm defects, higher sperm metrics, and higher membrane structural integrity with mitochondrial activity. Regarding motility patterns, the increases during the rainy season stand out in total and progressive motility, VAP, VSL, VCL, and subpopulations of rapid sperm. In summary, our results suggest that the adverse climatic conditions of the dry season in the semiarid region, mainly high solar radiation and temperature, considerably impair the epididymal sperm quality of red-rumped agoutis. On the contrary, the largest amount of sperm was obtained during this season, probably due to compensatory and adaptive mechanisms of the species to enable its reproduction throughout the year.
为了制定有效的野生啮齿动物管理和保护策略，了解与繁殖相关的方面，包括这种生理功能与环境的相互作用，是至关重要的。本研究旨在评估半干旱地区旱季和雨季的气候变化对红尾豪猪（Dasyprocta leporina）附睾精子特征的影响，红尾豪猪是一种豪猪形啮齿动物，研究较少，栖息在巴西的卡廷加地区。从 14 只豪猪的附睾尾部收集精子，每个季节（旱季和雨季）各 7 只个体。对运动参数、膜结构和功能完整性、线粒体活性、形态和形态计量学进行了评估。测量了环境变量：旱季和雨季的最高空气温度、相对湿度、风速、太阳辐射和总降雨量分别为 36.2°C 和 34.1°C、66.8% 和 80.1%、4.0m/s 和 1.9m/s、527.3W/m 和 441.8W/m、0.2mm 和 517.7mm。一些精子参数与环境变量之间存在很强的相关性，主要与精子运动能力的获得有关。旱季（1028.7 个精子/mL×106和 1361.2×10个精子）的精子浓度和收集的精子数量高于雨季（758.9 个精子×106/mL 和 714.6 个精子×10）。在雨季，精子缺陷较少，精子指标较高，膜结构完整性和线粒体活性较高。就运动模式而言，雨季的总运动和渐进运动、VAP、VSL、VCL 和快速精子的亚群的增加尤为明显。总之，我们的研究结果表明，半干旱地区旱季的不利气候条件，主要是高太阳辐射和温度，会极大地损害红尾豪猪的附睾精子质量。相反，在这个季节获得了最大数量的精子，这可能是由于该物种的补偿和适应机制，使其能够全年繁殖。
