Invited review: Reproductive and genomic technologies to optimize breeding strategies for genetic progress in dairy cattle

Abstract

Abstract. Dairy cattle breeders have exploited technological advances that have emerged in the past in regards to reproduction and genomics. The implementation of such technologies in routine breeding programs has permitted genetic gains in traditional milk production traits as well as, more recently, in low-heritability traits like health and fertility. As demand for dairy products increases, it is important for dairy breeders to optimize the use of available technologies and to consider the many emerging technologies that are currently being investigated in various fields. Here we review a number of technologies that have helped shape dairy breeding programs in the past and present, along with those potentially forthcoming. These tools have materialized in the areas of reproduction, genotyping and sequencing, genetic modification, and epigenetics. Although many of these technologies bring encouraging opportunities for genetic improvement of dairy cattle populations, their applications and benefits need to be weighed with their impacts on economics, genetic diversity, and society.

Symposium review: The choice and collection of new relevant phenotypes for fertility selection

“…Many new phenotypes have been proposed to better express the underlying biology of reproduction in cattle with minimal influence of producer management decisions. As well, with emerging technologies and data sources, there are opportunities to both better characterize and improve the accuracy of current traits, and potentially collect novel phenotypes at a national level (Crowe et al, 2018;Fleming et al, 2018). There is a plethora of novel phenotypes to describe many different aspects of female reproduction in dairy cows, and here we discuss some of those most attainable for implementation.…”

Whole genome sequence analysis to detect signatures of positive selection for high fecundity in sheep

“…Traditional animal breeding based only on the observed phenotypic data for low heritable characteristics such as fertility and health traits is often inaccurate, inefficient and time‐consuming (Fleming, Abdalla, Maltecca, & Baes, ; Rosati, Mousa, Vleck, & Young, ). Fortunately, advances in high‐throughput genome scanning methods, chiefly next‐generation sequencing technologies (NGS), have allowed us to identify causal genes and variants related to economically important traits and thus have proven to be a powerful genetic tool for interpreting the genetic underpinnings of complex traits in human and animal species (Sharma et al, ; Ziogas and Roukos, ).…”

DNA methylation pattern of the goat <i>PITX1</i> gene and its effects on milk performance

“…(1) CTCF can regulate gene expression by binding to the gene imprinting control region (ICR) (Dunn and Davie, 2003); (2) the STAT family of proteins are the main components in the JAK-STAT pathway, which is critical to the proper development and function of the mammary epithelial tissue (Haricharan and Li, 2014); (3) SMAD proteins are Smad signaling components -in mammary epithelial cells, Smad signaling acts to antagonize JAK-STAT signaling to regulate mammary gland differentiation (Cocolakis et al, 2008); (4) CDEF could regulate the cell cycle of epithelial cell (Müller and Engeland, 2010); and (5) SP1 and KLFS could regulate the expression of genes containing GC-rich promoters (Kaczynski et al, 2003), and these transcription factors could influence the function of PITX1 and therefore affect lactation performance.…”