This is a literature review in which we present, in a narrative form, the results and conclusions of original research on the pathophysiology and diagnostic methods for the identification of XX/XY chimerism or freemartin anomaly in cattle. Freemartinism affects up to 92% of the pregnancies involving different sex twins. Exchange and transfer of cells and hormones from the male to the female cause suppression of the female’s reproductive system development and lead to the development of a masculine reproductive system that produces infertile females. Since diagnosing this anomaly is important to stockbreeders, efficient detection techniques have been development.

En trópico alto los sistemas silvopastoriles son alternativas sostenibles que mejoran la disponibilidad y calidad del forraje para la ganadería, estos agroecosistemas requieren la propagación de especies arbustivas forrajeras con alta capacidad productiva como el Tilo (Sambucos peruviana). La investigación evalúa la eficiencia de tres hormonas naturales, cuatro sintéticas y un biofertilizante de suelos en el enraizamiento y brotación de estacas de Tilo. Se empleó un diseño de bloques completos al azar, con veintiún tratamientos, cada uno con tres repeticiones, determinando el comportamiento de seis variables a través de ANOVA, normalidad (Shapiro-Wilk), homogeneidad de varianzas (Levene´s) y Post-hoc (Scott-knott o Bonferroni). Los resultados muestran respecto a la variable número de brotes que los mayores promedios se alcanzaron con T12 (canela) y T11 (sábila) y se acepta la H0 (P> 0.05). Mientras que para las cinco variables restantes se identificó diferencia estadísticamente significativa (P< 0.05). En peso de brote (g.) y longitud de brote (cm.) se obtuvieron los mejores resultados con T3 (Ácido giberélico); para longitud de raíz (cm.) el mejor comportamiento fue con T10 (micorriza y alpiste); para peso de raíz (g.) y altura de planta (cm) el promedio mayor fue con T4 (ANA+ IBA).

Ecosystem services are configured from potential benefits associated with the functions of the ecosystem services which are specified in real time, are defendants, used or enjoyed, and per saying when society assignes instrumental values. For this review, we assume the classification of ecosystem services proposed in the document The evaluation of the Millennium Ecosystem Assessment (2005), which are classified as provisioning services, cultural and regulation. Regulating services are great importance to human welfare, are obtained ecosystems directly, without going through processes processing, such as clean air, maintenance of biogeochemical cycles and disease prevention, among others. then presents a literature review on the trend of regulating ecosystem services, their relationship with the quality of water, air, and biological control biodiversity that, in order to give the reader a precise idea about the relevance of these services and the real benefits that society receives from them, but also, an idea of how they are being altered and that negative impacts on the welfare of the society.