Total apparent digestibility and nitrogen balance in Cinta Senese pigs. Utilization of field bean (Vicia faba L.) [Tuscany]

This work aimed at studying the digestive capacity and the nitrogen balance in Cinta Senese pigs in comparison with Large White pigs, employing field bean and soybean as protein sources. Twelve 5-month old barrows, 6 Cinta Senese (CS) and 6 Large White (LW), were submitted to trials in metabolism cage to determine apparent digestibility and nitrogen balance of diets containing soybean meal (S diet) or field bean (F diet), 10% and 20% respectively, as protein source. CS showed lower digestibility coefficients for all the nutritive fractions than LW pigs (DM: 85.33% vs 82.87%; CP: 86.38% vs 84.17%; ADF 51.35% vs 43.31%). Nitrogen retention, also, was less favourable in CS pigs, which showed a 20% higher excretion (fecal + urinary) value of total ingested N (59.88% vs 48.60%). Differences between the diets were limited. Field beans, containing only 0.25% of tannin as used here, appear a valuable protein source in pig nutrition, even in local breeds such as CS