Research objectives and content
The improvement of production quality, health and competitiveness depends on the genetic merit of the EU livestock population. To improve genetic gain of farm animals in general and in cattle in particular, it is necessary to overcome the current low selection intensity of females, due to the small number of offsprings that can be generated by a single individual. Increased selection intensity of females has been attempted by superovulation, oocyte recovery by follicular aspiration and IVM-IVF for production of embryos, but these procedures give variable and unpredictable results. The main factor leading to variation in response to these techniques is the large within and between variation in oocyte quality. Moreover nutritional and metabolic stress linked to high productive performances in both dairy and beef cattle are known to affect fertility and embryo quality, and can be used to manipulate oocyte developmental competence. Thus, the aim of this project is to obtain a better understanding of the factors that regulate the acquisition of developmental competence by the oocyte. The specific focus and aim of this project is to define the effect of metabolic and nutritional stressors on the above mechanisms. The results of this research will be relevant to the improvement of reproductive performances of valuable animals. Training content (objective, benefit and expected impact)
Previous works of the applicant has always been related with the nutrition-reproduction relationships in sheep. The variation in embryo mortality in sheep in the first two weeks of pregnancy has been studied. The host group has a wide experience in the same field,
nutrition-reproduction relationship, and they can contribute their knowledgment in follicular dynamics, oocyte development and their studies with other ruminant species. The main objectives are to teach techniques to study the oocyte competence and follicular dynamics: oocyte and follicular recovery and clasification, IVM and IVF, culture systems, immunocytochemistry and employment of several instruments as electron microscopy, confocal microscopy and flow cytometry. Moreover, it is an opportunity to enlarge the number of species studied. The techniques could be carried out in studies about sheep and the selection programme in Rasa Aragonesa breed, breed employed in studies of embryo vitrification by the group of origin.
Links with industry / industrial relevance (22)
Employment of oocytes will be able to accelerate the genetic selection, because it could increase the number of offspring obtained from females with a high genetic merit. This would achieve to improve the productive performances faster than other assisted reproductive techniques.