Emerging technologies with the potential to improve feed efficiency in swine

Abstract

Although there are metabolic modifiers such as injectable porcine somatotropin available for some pork industries, producers are very much interested in orally active compounds that may cause metabolic shifts that result in similar improvements in feed efficiency and body composition. The purpose of this review is to discuss some of the alternatives that may be used to manipulate growth, feed efficiency, and body composition in growing pigs. The new technologies include immunization against gonatotropin releasing factor (GnRF) to enhance the use of boars while the orally active dietary additives discussed include ractopamine, cysteamine, chromium, betaine, and dietary neurolepetics. Cysteamine may stimulate somatotropin secretion in pigs and under some circumstances can increase ADG and decrease back fat. However, responses are variable and further work is needed to define the dose response curve. Responses to dietary chromium have also been variable and this may be in part due to inefficient digestion and absorption. Micro- and nano-particles of chromium may increase efficacy of dietary chromium and improve insulin sensitivity and growth performance in pigs. Dietary betaine has the potential to reduce maintenance requirements and in some circumstances this additional energy can be used for protein deposition. Dietary neuroleptics offer a means of reducing sexual and aggressive activities in finisher pigs, specifically boars, and improve growth performance. Immunization against GnRF reduces boar taint, sexual activity, and aggression in boars and improves lifetime feed efficiency over that of barrows. Responses to dietary feed additives are generally not as powerful as the responses to porcine somatotropin but they do offer an alternative means to manipulate growth performance and carcass quality.