Reproductive technologies and animal welfare.

In general, animal welfare and reproduction are strictly related. Numerous studies have reported that both chronic and acute stress and the associated reduced level of animal welfare may impair the reproductive functions in both males and females. For instance, stress can reduce the secretion of gonadotropin-releasing hormone (GnRH) by the hypothalamus and consequently decrease the production of luteinizing hormone and follicle-stimulating hormone (FSH) by the hypophysis and sex steroids from the gonads induce ovulation failure and the formation of cystic follicles . As a consequence, a decreased libido is detected in males and reduced fertility and lack of embryo implantation are observed in females. Conversely, how reproductive management practices may affect animal welfare has received much less attention so far. In particular, when breeding technologies are applied, three distinct elements have to be considered and the synergic effect they can produce on the animals: handling, restraint, and the application of the breeding technology per se. Reproductive technologies have been developed in the last 60 years, and therefore, the animals are unlikely to possess any innate adaptive mechanism to cope and generally perceive them as adverse. However, modern reproductive technologies may also favor animal welfare by minimizing the effect of unfavorable events (e.g., dystocia, mortality). Therefore the present chapter aims at identifying the most common practices and assessing the impact, either positive or negative, of these reproductive technologies on animal welfare.