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1.
Poult Sci ; 102(10): 102887, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37572620

RESUMO

The United States is the largest broiler producer in the world, and Americans consume about 45 kg of chicken per capita per year, which generates substantial economic and environmental footprints. We conduct techno-economic analysis and life cycle assessment (TEA/LCA) to evaluate the sustainability performance of the U.S. broiler industry and quantify the cost, greenhouse gas (GHG) emissions, energy, water, land, fertilizer, and respiratory impacts of 7 broiler production scenarios for a contract Grower, Integrator, and Combined control volume. The assessment is a farm-gate to farm-gate analysis that includes capital cost of chicken houses, labor, chicks brought into the farm, feeds, on-site fuels, and on-site emissions. We found that economics for the Integrator are profitable and dominated by the cost of corn and soybean meal feeds, payments to the Grower, and revenue from live broilers. Additionally, we found that economics for the Grower generate modest return on investment (ROI) largely based on the cost of houses and labor when compared to contract revenue from the Integrator. Environmental impacts for GHG, energy, and respiratory effects are primarily associated with upstream feed production (roughly 65%-80% of total impacts) and on-site fuel consumption (∼20%-35% of total impacts), while those for water, land, and eutrophication are almost entirely attributable to upstream feed production (litter spreading has a low economic allocation factor). Tradeoffs among sustainability metrics are further explored with a sensitivity analysis and by evaluating cost/environmental benefit scenarios.


Assuntos
Galinhas , Gases de Efeito Estufa , Humanos , Estados Unidos , Animais , Meio Ambiente , Fazendas , Zea mays , Água , Efeito Estufa
2.
Poult Sci ; 99(6): 3266-3279, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32475462

RESUMO

Genetic selection in broilers has resulted in improved growth performance, meat yield, and feed conversion efficiency. However, consumers have become increasingly concerned about modern broiler welfare that is related to their rapid growth rate, which may be alleviated by nutrient dilution. This study was conducted to investigate the effects of dietary amino acid (AA) reduction on the growth performance and internal organ development of different genetic strains of broilers. A randomized completed block design with a factorial arrangement of 10 treatments (5 strains × 2 AA levels) was used. The 5 different strains of broilers were fed either a control diet, with digestible AA (lysine, total sulfur AA, and threonine) at the highest recommended levels for the 5 strains, or an AA-reduced diet, with the digestible AA being 20% lower than the control diet. Feed conversion ratio was increased by AA reduction in all 5 strains during day 0-14, 14-28, and 28-41 but was not affected from day 41-55. Body weight and feed intake responses to AA reduction varied in the different strains and ages of birds. Liver weight relative to BW on day 40, and weights of the duodenum and jejunum relative to BW on day 60 were increased by decreasing the dietary AA concentration. These results indicate that the birds had adjusted their organ growth and metabolism in response to increases in digestion, absorption, and utilization efficiency to accommodate a decrease in dietary AA content. Surprisingly, the cost of feed required to produce the same BW was decreased in 4 of 5 strains on both day 41 and 55, which was largely because of the lower price of the diets containing reduced AA levels and the later compensatory growth experienced by the birds fed AA-reduced diets. In the future, when dietary AA levels need to be adjusted to control growth rate and improve welfare status, the genetic strain, age of the birds, and targeted goals need to be taken into consideration.


Assuntos
Aminoácidos/deficiência , Metabolismo Basal , Bolsa de Fabricius/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Trato Gastrointestinal/crescimento & desenvolvimento , Ração Animal/análise , Criação de Animais Domésticos/economia , Animais , Bolsa de Fabricius/efeitos dos fármacos , Galinhas/genética , Galinhas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Masculino , Mortalidade , Tamanho do Órgão/efeitos dos fármacos
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