Digestive utilization of novel biodegradable plastic in growing pigs

Two experiments were carried out to determine the effect of poly(3-hydroxyb utyrate-co-3-hydroxyvalerate) (PHBV) and polycaprolactone (PCL) inclusion ( Exp. 1), and of PHBV pre treatment with sodium hydroxide (Exp. 2) on the di gestibility of diets in growing pigs. In Exp. 1, eight male castrated Large White pigs (initial liveweight 24 kg; final liveweight 64 kg) received rat ioned amounts of a cereal-based diet containing 0 (C) or 8 % of either barl ey straw meal (S), PHBV (PI) or PCL (P2) in a replicated double 4 x 4 Latin square design. In Exp. 2, ten animals (23-84 kg liveweight) were fed the s ame standard diet including 0 (C), 10 or 20% of either untreated (P10, P20) or pretreated PHBV (tP10 and tP20) in a replicated double 5 x 5 Latin squa re design. Inclusion of untreated biodegradable plastic and straw negativel y influenced (P < 0.01) organic matter and energy digestibility. Untreated PHBV was poorly digested. The analogy of data indicates that PCL was even l ess digested. Untreated plastic can be considered as undegradable material in the gastrointestinal tract of pigs. In contrast, pretreatment (Exp. 2) s ignificantly increased (P < 0.01) PHBV, organic matter and energy digestibi lity. Independently of the amount included, 37 % of pretreated PHBV x;as di gested on average. ((C) Elsevier / Inra).