Year of Publication


Document Type





Animal Science

First Advisor

Merlin D. Lindemann


The initial study herein assessed mineral digestibility in situations when reducedamounts of inorganic and organic (proteinates) trace minerals (TM) were fed in finishingpigs, and their long-term effects on body mineral status. The second study was aslaughter-investigation that tested the impact of lean growth potential on phosphorusbody accretion from 30 to 110 kg.Organic TM exhibited neither improvement in digestibility nor in total retention;fecal excretion responded quantitatively to mineral intake independently of the source.Contents of copper in kidney and zinc in liver were higher for pigs fed the organic form.Phosphorus content was linearly related to live weight, empty body weight, andnitrogen content. Phosphorus accretion was very similar for both genetic backgrounds,with gilts retaining more mineral (Pandlt;0.05) than barrows. A N/P deposition ratio of 5.14was determined for pigs of both genders and genetic backgrounds to further predictphosphorus requirements based on protein accretion.Reduction of TM waste from growing-finishing pigs may be best addressed bylimiting their dietary inclusion rather than by using organic forms. Data from the secondstudy may be useful for an accurate estimation of phosphorus requirements, whichaccounts for variations in lean accretion rate.