Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina; Ecología-Educación Ambiental, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, UNRC, Ruta Nacional N 36-km 601, Río Cuarto, Córdoba, Argentina.
Ecología-Educación Ambiental, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, UNRC, Ruta Nacional N 36-km 601, Río Cuarto, Córdoba, Argentina.
Ecotoxicol Environ Saf. 2015 Aug;118:118-125. doi: 10.1016/j.ecoenv.2015.04.017. Epub 2015 Apr 30.
Perturbations of water bodies near agricultural and livestock systems can affect embryonic and larval stages of anurans and negatively impact adult populations and structure of amphibian communities. This study is focused on early development of Rhinella arenarum, for which body growth, abnormalities in the oral disc and genetic damage on erythrocytes were analyzed to establish the impact of agroecosystems on local populations of amphibians. Tadpoles and metamorphs of R. arenarum were collected in three agroecosystems (namely, C1, C2, and C3) and in a site without agricultural and livestock activities (SM) from central Argentina. Egg masses of C1 were extracted for breeding tadpoles under laboratory conditions (Lab). Tadpoles were in small size and lighter in weight in C1 and C2. Metamorphs were shorter and lighter in weight in C1 and C3. In SM and Lab samples, no tadpoles with abnormal LTRF (labial tooth row formula) or without labial teeth were observed. In C1, the highest frequency of abnormal LTRF was recorded and was the only site in which tadpoles without labial teeth were found. In C1 and C2 the tadpoles had highest micronucleus frequencies and nuclear abnormalities. C1 can be considered as the site with the highest anthropogenic perturbation and with less healthy tadpoles. Livestock practices such as alternating cattle between parcel and keeping a buffer between crops and water bodies, would allow a better development of the first aquatic stages that are essential for the conservation of the anuran populations.
农业和畜牧业系统附近水体的扰动会影响两栖类动物的胚胎和幼虫阶段，并对成体种群和两栖类动物群落的结构产生负面影响。本研究集中于 Rhinella arenarum 的早期发育，分析了其身体生长、口腔盘异常和红细胞遗传损伤，以确定农业生态系统对当地两栖类动物种群的影响。在阿根廷中部，从三个农业生态系统（即 C1、C2 和 C3）和一个没有农业和畜牧业活动的地点（SM）收集了 Rhinella arenarum 的蝌蚪和变态体。从 C1 中提取卵块用于在实验室条件下繁殖蝌蚪（Lab）。C1 和 C2 中的蝌蚪体型较小，体重较轻。C1 和 C3 中的变态体较短，体重较轻。在 SM 和 Lab 样本中，没有观察到具有异常 LTRF（唇齿列公式）或没有唇齿的蝌蚪。在 C1 中，记录到异常 LTRF 的最高频率，而且是唯一发现没有唇齿的蝌蚪的地点。在 C1 和 C2 中，蝌蚪的微核频率和核异常率最高。C1 可以被认为是受到人类干扰最大且蝌蚪最不健康的地点。牲畜管理措施，如在地块之间交替放牧牛群，并在作物和水体之间保持缓冲区，将有助于第一水生阶段的更好发育，这对于保护两栖类动物种群至关重要。
