Soybean vs. Pea Bean in the Diet of Medium-Growing Broiler Chickens Raised under Semi-Intensive Conditions of Inner Mediterranean Areas: Growth Performance and Environmental Impact

SIMPLE SUMMARY: Growth performance of medium-growing broiler chickens raised under semi-intensive conditions was evaluated comparing two different dietary treatments and two different genotypes. Starting from the dietary ingredients traditionally used, soybean was totally replaced by pea bean. The experimental diets were also compared from an environmental point of view simulating the annual global warming potential of the diets. Neither genotype nor dietary treatment affected feed consumption and growth performance, suggesting that the total replacement of soybean with pea bean can be a valuable feeding strategy, also from the economic point of view. A diet containing pea slightly reduced the total greenhouse gas and carbon dioxide emitted on a yearly basis. The results of the present study suggest that replacing soybean with pea bean can be a sustainable feeding strategy in broiler chicken production of inner Mediterranean areas, from both economic and environmental perspectives. ABSTRACT: The effects of Glycine max L. (SOY) vs. Pisum sativum L. (PEA) in the diet were investigated on in vivo performance of two medium-growing broiler genotypes and on environmental impact. Sixty Kabir Red Plus and sixty New Red chickens were randomly allocated in 20 pens (n = 6 birds per pen). Each pen, i.e., experimental unit, received 1.18 kg dry matter (DM) including soybean (3.39%) in SOY, or pea bean (6.78%) in PEA groups. DM intake, DM refusals and bodyweight (BW) were recorded on pen basis, and average daily gain (ADG) and feed conversion rate (FCR) were calculated. Data on in vivo performance were processed by ANOVA General Linear Model followed by Student–Newman–Keuls post hoc test. Greenhouse gas (GHG) emissions were evaluated on a year basis by GLEAM-i software. The diet did not affect (p > 0.05) DM intake and DM refusals, BW, ADG and FCR. Diet x genotypes affected (p < 0.05) DM intake and DM refusals. PEA diet, cheaper than SOY diet, allowed the reduction in total GHG and CO(2), and of meat emission intensity. However, an increase in total CH(4) and N(2)O emissions was observed. The replacement of soybean with pea bean can represent a possible management strategy to reach trade-off between good farming practices and environmental protection on small-scale poultry farms of inner Mediterranean areas.