| Summary: | The cessation of milking, or dry off, is a regular management practice in dairy animals. This practice initiates a non lactating, or dry, period. Milking begins again after parturition. Provision of a dry period is done largely to improve milk production in the subsequent lactation, but also to address udder health issues (intramammary infections); therefore, the majority of literature focuses on these areas, and little consideration is given to the welfare of the individual animal. The goals of this thesis were to develop a better understanding of how common dry off methods, and the dry period itself, affect three components of animal welfare: biological functioning, affective states and natural behaviour in dairy cows and dairy goats. The first study in this dissertation explored how high producing dairy cows experience abrupt cessation of milking, a commonly utilized procedure. The results suggested that cows remain motivated to leave the pen around milking time, and that these cows leak milk, a risk factor for intramammary infections. Since dry off methodology is not well understood in dairy goats, the second study shifted towards describing dry off management used by goat producers. Although similarities to cow management exist, goat producers show more flexibility in decision making around dry off, sometimes opting to give high producing goats shorter, or even no, dry periods. Within this work, concerns were also identified regarding metabolic issues in goats (pregnancy toxemia and ketosis). Therefore, the final studies combined to explore the early identification of these issues in goats. The third study validated the use of data loggers on goats, allowing for automatic recording of lying behaviour. The fourth study applied these loggers to monitor the lying behaviour of goats during the dry period, and searched for links to pregnancy toxemia and ketosis. The results showed that at-risk goats increase their lying time and decrease their activity, making lying behaviour a promising indicator of metabolic issues. Finally, three key areas are discussed for future research, namely continued work in evaluating affective states in dairy animals, benchmarking of on-farm research results, and exploring the possibilities of deviating from standard annual lactation cycles. === Land and Food Systems, Faculty of === Graduate
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