Jennie E. Pryce

This collection features four peer-reviewed reviews on infertility and other reproductive disorders in dairy cattle. The first chapter discusses the physiology of the main impediments to fertility and management issues that need to be addressed to ensure good fertility of dairy cows. The chapter focusses on parturition and uterine health, the importance of the post-partum environment and the role of oestrus, as well as methods of establishing pregnancy and the effect of heat stress on cows’ fertility. The second chapter considers recent developments in automated monitoring of livestock fertility and pregnancy, focussing on its implementation in dairy cattle production. The chapter explores the physiological basics of the reproductive cycle in dairy cattle and the use of artificial intelligence to monitor and report changes in animal behaviour. The third chapter reviews progress in understanding the role of genetics in addressing the decline in fertility rates in dairy cattle. The chapter discusses strategies to improve the reproductive performance of dairy cattle, including the use of different breeds, measures of fertility and genomic data. The final chapter reviews best practices to detect reproductive problems and limitations in dairy cattle. The chapter identifies key areas which are known to limit performance and provides strategies which can be implemented to optimise reproductive performance and maximise animal health.

This specially curated collection features four reviews of current and key research on heat stress in dairy cattle. The first chapter outlines technologies to breed for more heat tolerant dairy cattle, exploiting either between or within breed genetic variation in the trait. It discusses future perspectives on the use of different tools to achieve accelerated improvements of this important trait. The second chapter discusses breeding goals and multi-trait selection to balance production and non-production traits. It considers newer breeding objectives such as ensuring that cattle can adapt to a changing climate, including breeding for heat tolerance. The third chapter reviews challenges facing smallholder dairy farmers in Asia. These include the impact of high temperatures and humidity on milk yield, reproductive efficiency and animal health. The chapter places these challenges in the context of the broader economic constraints faced by smallholders and how they can be overcome. The final chapter highlights constraints in improving smallholder dairy production in Sub-Saharan Africa. Issues include developing breeds balancing yield with resilience to local climatic conditions. The chapter reviews ways of Improving breeding and productivity, as well as broader organisational support