Effect of Australian sweet lupin (Lupinus angustifolius L.) inclusion levels and enzyme supplementation on the performance, carcass composition and meat quality of grower/finisher pigs

Abstract

Two hundred and twenty-four crossbred male pigs (Large White × Landrace, initial bodyweight 27.2 kg ± 0.22) were used to determine the influence of dietary Australian sweet lupin (ASL) inclusion level and enzyme supplementation on growth performance, carcass composition and meat quality. The experiment was a 4 × 2 factorial design with the respective factors being ASL inclusion level (Lupinus angustifolius L., cv. Mandelup; 200, 250, 300 and 350 g/kg, in replacement of soybean meal) and enzyme supplementation (without or with supplemental enzyme; Allzyme SSF). Pigs (7 pigs per pen × 4 replicates per treatment = 28 pigs per enzyme by lupin-level combination) were fed grower diets between 27 and 50 kg, finisher diets between 50 and 75 kg and pre-sale diets between 75 and 107 kg, and daily gain and feed intake were measured weekly. At ~107 kg liveweight, the pigs were slaughtered at a commercial abattoir and carcass composition was measured. Meat quality (pH, surface exudate, drip loss, cooking loss, meat colour and shear force) was measured from selected pigs (n = 18) fed the lowest and highest lupin diets without enzyme supplementation. Increasing the ASL inclusion level to 350 g/kg did not alter (P > 0.05) growth performance of pigs and did not influence (P > 0.05) carcass composition and meat quality. Likewise, addition of supplemental enzyme had no effect (P > 0.05) on growth performance and carcass composition. Lack of performance response to added enzyme complex is likely due either to the use of enzyme complex that was not substrate-specific for the lupin non-starch polysaccharides or to the high specification of the experimental diets, which was inevitable when increasing inclusion levels of lupins. The results show that a current variety (Mandelup) of ASL can be used in grower/finisher diets up to 350 g/kg without compromising growth, carcass composition or meat quality of pigs.