Genetic, cytogenetic and morphometric analyses in the study of reproductive problems that affect animal productions in the main livestock and pets species

Zootechnics has the mission to improve animal production, according to the human needs, that will influence market demand and animal and human health. Animal reproduction gives an important contribution giving rise to an "extreme Tango" in which genetics is the crazy score with a solid melody but which can change depending on the context in which this music is played. This thesis reports the research studies carried out during the doctorate. The Disorders of Sexual Development are the main topic of the first chapter. These are genetic diseases involving the reproductive system that cause sterility to the carriers and economic losses to the breeders. The animals involved in this study are dogs and horses, they were examined clinically, cytogenetically and genetically in order to identify DSD etiopatogenesis of each subject. The main topic of the second chapter is the improvement of stallions’ sperm quality using phytotherapic drugs. This study has a dual purpose, to improve the natural breeding and the techniques of artificial insemination. Morphometric analyzes and chromatin fragmentation tests were performed on the ejaculates in addition to the qualitative and quantitative evaluations routinely carried out. The Third Chapter describes a work born by a collaboration among different research groups. Exploiting the training acquired on the morphometric evaluation of the spermatozoa of different mammals’ species we have applied the same techniques on the spermatozoa of Apis mellifera Ligustica, in order to characterize its semen.