The replacement gilt: Current strategies for improvement of the breeding herd

Abstract

The efficiency of swine production is affected by many factors. One of the most economically important factors is gilt reproductive performance. To achieve satisfactory results in breeding, both environmental and genetic factors must be monitored and constantly improved. For many years, intensive selection in the swine industry for increased carcass muscle to fat ratio has led to deterioration in some reproductive traits (eg, less favorable development of the reproductive system in gilts, problems with fertilization, large litters but tiny piglets). In recent years, many producers have focused on increasing litter size and weaning weights of piglets in addition to an emphasis on increasing sow productive life span. In replacement gilts, the systematic evaluation of both reproductive and structural soundness is of paramount importance. The main aim of this review is to summarize the current criteria for selecting replacement gilts.