Utilization of milk minerals by Iberian suckling piglets

Abstract

Little information is available concerning mineral metabolism in suckling piglets. The utilization of milk minerals and the mineral composition of Iberian (IB) suckling piglets were studied in two consecutive experiments at different ambient temperatures (trial 1, 27 ± 2°C; trial 2, 22 ± 2°C). Milk composition and the piglets’ performance were determined weekly over a 34 days lactation period and, at the end, body mineral contents were analyzed and mineral retention and bioavailability were calculated. The ash content in IB sows’ milk and in suckling IB piglets was found to be higher than that reported for lean genotypes. During lactation, mean ash content per unit of body weight gain in IB piglets (40.6 g kg-1) was 42% higher than that observed for lean breeds, and weaned IB piglets contained 60% more Ca (11-12.7 g kg-1 empty body weight) and P (7-7.5 g kg-1 empty body weight), compared with conventional pigs. Minerals from milk were retained by the IB piglet with an overall efficiency of 78.3%, 66.3% and 48.7% for Ca, P and Mg, respectively. Significant differences between trials were observed in the mineral fraction composition of the milk, which were reflected in piglet body composition at weaning, presumably due to differences in ambient temperature. Present findings underline genotype differences in mineral composition of sow’s milk and suckling piglets and may provide a useful starting point for formulating milk-replacer diets for IB piglets.