Effects of zinc on growth performance

Project Title: The effects of increasing levels of Availa Zn compared to inorganic Zn on growth performance, carcass characteristics, and economics of finishing pigs

Background Information

High capital costs of building modern confinement finishing barns encourage pork producers to reduce floor space allowance for each pig in an effort to spread fixed building costs over more pigs.  Reduced floor space allowance or crowding of pigs clearly depresses performance of individual pigs (Brumm and NCR-89, 1996).  However, even though performance of individual pigs is depressed with crowding, overall output of the barn measured as pigs or pounds of pork increases when pigs are crowded (Kornegay and Notter, 1984).  Efforts to mitigate the crowding-induced depression in pig performance by increasing dietary energy, and amino acids (Brumm and Miller, 1996) or including an antibiotic in the diet (Moser et al., 1985) have not been successful.  Most researchers agree that crowding is a stress to the animal.  Psychological stress causes redistribution of body zinc stores and depressed serum zinc concentration in rats (Tao et al., 2013).  Similarly, highly available dietary zinc ameliorated the negative effects of heat stress on intestinal integrity of pigs (Sanz Fernandez et al., 2014).  Anecdotal observations suggest that performance of pigs under stress improves when a highly-available source of zinc is present in the diet (Dr. Zach Rambo, Zinpro Corporation).  This experiment is designed to test this observation under controlled conditions.  

Study Objectives

  1. To evaluate the effect of increasing dietary levels of zinc amino acid complex (Availa Zinc, AvZn) on growth performance and carcass composition of growing-finishing pigs housed with reduced floor space allocation

  2. Determine the level of Availa Zinc inclusion that optimized pig performance and profitability.  


March – April, 2015                   Finalize barn protocol, secure necessary supplies

May – Aug, 2015                       Conduct first replicate of experiment

Sept, 2015 – Jan, 2016               Conduct second replicate of experiment

Feb – March, 2016                     Summarize results and conduct statistical analysis

Summer or Fall, 2016                 Final results available

More Info