Optimizing nutrient efficiency is essential to increase pig chain sustainability, since it may reduce nutrient excretion and production costs. This study was thus undertaken to evaluate if a feeding strategy of growing-finishing pigs based on the modelling of nutrient requirements according to a target of performance could achieve at least similar growth performance, carcass traits and meat quality as a strategy based on standard recommendations with rather large safety margins, whilst reducing the environmental impacts evaluated by life cycle assessment. The objective of this study was to evaluate the effect of reducing dietary nutrient content for pigs from 25 to 130 kg live weight, on performance, carcass traits, meat quality and environmental impact. Forty gilts and 40 barrows were distributed in a randomized block design with two treatments and 10 replications per treatment, with four animals per experimental unit. The feeding program was in four phases. Two diets were formulated for each feeding phase. One was adjusted using the InraPorc® model to minimize crude protein, amino acid and phosphorus excess (LN), and the other (ST) was formulated with standard Brazilian recommendations.
No differences were observed on performance. The mean ADG and ADFI were 0.919 and 2.46 kg/day, respectively. Carcass characteristics and meat quality were also not affected by the experimental diets. The average total feed cost was 6.8% lower for animals fed the LN diets. For nitrogen and phosphorus balance, there was no statistical difference in retention, but nitrogen and phosphorus intakes were 15.8% and 9.42% lower for pigs fed LN diets, respectively, and the excretion levels were 24.1% and 14.6% lower for pigs fed LN diets, respectively. Life cycle assessment showed that LN strategy can reduce the environmental impacts of climate change and terrestrial ecotoxicity by about 4%, acidification and eutrophication by 8% and 10%, respectively, and land occupation by 9%.
Data suggest that nutritional adjustment is a valuable alternative to standard formulations, without affecting performance, but lowering costs and reducing environmental burdens.
Monteiro, A. N. T. R., Bertol, T. M., de Oliveira, P. A. V., Dourmad, J. Y., Coldebella, A., and Kessler, A. M. (2017). The impact of feeding growing-finishing pigs with reduced dietary protein levels on performance, carcass traits, meat quality and environmental impacts. Livestock Science, 198, 162-169. http://doi.org/10.1016/j.livsci.2017.02.014