Alterations of Porcine Skin Acid Mucopolysaccharides in Zinc Deficiency

Abstract

Zinc deficiency is overtly manifested as a dermatitis in swine; therefore, the purpose of this investigation was to determine possible zinc-related alterations in the metabolism of the skin acid mucopolysaccharides (AMPs). Eighteen 4-week-old Yorkshire pigs were randomly allocated to one of three dietary treatments. Six animals were fed a semipurified, zinc-deficient, basal diet containing 20 ppm zinc. Six animals served as pair-fed controls and were fed the basal diet supplemented with 90 ppm zinc as zinc carbonate. The remaining six animals were fed the zinc-supplemented diet on and ad libitum schedule. All animals were killed after 36 days when overt deficiency symptoms were apparent in those animals fed 20 ppm zinc. Skin AMPs were isolated. Total hexosamine and galactosamine indicated no alteration in total AMPs. Fractionation of total AMPs into consitituent sulfated and nonsulfated components revealed a significant increase in hyaluronic acid. No statistical difference in sulfated AMPs was found in skin from deficient and pair-fed animals, which was in accord with an in vitro sulfur-35 uptake study.