ARTIFICIAL REARING OF COLOSTRUM-DEPRIVED PIGLETS USING IRON CHELATORS: THE EFFECTS OF ORAL ADMINISTRATION OF EDDHA WITH AND WITHOUT BOVINE OR PORCINE IMMUNOGLOBULINS ON PIGLET PERFORMANCE AND IRON METABOLISM

Abstract

The iron chelator ethylene diamine-di-orthohydroxyphenyl acetic acid (EDDHA) was fed to 79 colostrum-deprived piglets with or without bovine or porcine serum immunoglobulins. Piglets that received bovine immunoglobulins from birth to day 14 had significantly lower survival rates, average daily weight gains and plasma immunoglobulin concentrations than piglets that received porcine immunoglobulins on the first day after birth. Piglets that received porcine immunoglobulins on day 1 followed by either bovine or porcine immunoglobulins on days 2–14 had significantly higher average daily gains than piglets that received no immunoglobulins on days 2–14. The addition of EDDHA to piglet's diets from birth to day 14 caused significant decreases in piglet average daily weight gains but had no effect on survival. EDDHA also caused significant reductions in packed cell volume and hemoglobin concentrations during the period it was included in the diet but these effects ceased when EDDHA was withdrawn. The effects of EDDHA on iron metabolism and excretion in the piglet were studied further using [59Fe]. Eight piglets were fed a commercial milk replacer containing either 0 or 37.5 mg kg−1 body weight d−1 of EDDHA. Piglets that received EDDHA had significantly longer plasma iron disappearance rates but did not significantly differ in hematocrits or plasma iron concentrations. Oral administration of EDDHA significantly increased the excretion of [59Fe] in the feces and urine and significantly reduced the incorporation of [59Fe] into red blood cells. There were no treatment differences in the distribution of [59Fe] in the livers or spleens of the piglets. Key words: EDDHA, immunoglobulins, piglet, artificial rearing, [59Fe]