Comparative effects of dietary fat and fibre in Alentejano and Large White piglets: Digestibility, digestive enzymes and metabolic data

Abstract

An experiment involving 24 Large White (LW) and 24 Alentejano (AL) piglets weaned at 21 days of age was conducted to study the effects of dietary fat and fibre on digestive capacity, and metabolic parameters in both genotypes, according to 2×2×2 factorial arrangement, with two genotypes, two levels of fibre (0 or 15% of wheat bran) and two sources of fat (olive oil or beef tallow). Total tract apparent digestibility (TTAD) was measured and blood samples were taken at fasting and throughout 5 h after meal. Average TTAD in AL and LW piglets, respectively, were 80.2 and 77.9% for energy, 69.4 and 61.4% for fat, 63.0 and 52.6% for NDF, and 39.8 and 13.1% for ADF. Wheat bran reduced TTAD of energy, fat and ADF by 5, 10 and 10 percentage units, respectively, in LW breed, and by 2, 10 and 4 percentage units, respectively, in AL breed. Total activities of pancreatic lipase, trypsin and amylase, and intestinal maltase at 49 d of age were 2.0, 1.5, 5.0 fold and 60% higher, respectively, in Alentejano piglets. For a constant nitrogen intake, daily nitrogen retention was greater in LW than in AL piglets, i.e., 6.7 vs. 5.8 g d −1, respectively. The maximum serum urea level was observed, 4 h after the meal, for diets containing wheat bran, i.e., 66.1 mg/100 ml and 53.1 mg/100 ml in AL and LW piglets, respectively, but LW breed exhibited higher levels of triglycerides, HDL-cholesterol and LDL-cholesterol.