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The land application of manure involves several environmental risks such a contamination of soil and water by nitrates, P, trace elements, etc. One way to minimize the excretion of N and P is to adjust the nutritional content of the feed to the animals’ requirements, but sometimes this management increases facility costs. The objective of this study was to asses, under experimental conditions, the animal responses and environmental impacts of a daily multiphase feeding systems (DPF) compared to a three-phase feeding system (3PF), on growth performance, body composition, and N and P excretions. A total of 104 female pigs were randomly assigned to 8 pens, each housing 13 animals. Only 10 pigs per pen were used for body composition measurements. Feeds for the 3PF and DPF treatments were obtained by mixing two feeds, one with a high nutrient concentration and the other with a low nutrient concentration.
The DPF pigs tended (P=0.08) to consume more feed (+3.7%) than the 3PF pigs, but only during the first feeding phase. The DPF pigs consumed 7.3% less protein (P<0.01) but a similar amount of total P. For the whole growing period, the DPF pigs tended (P=0.08) to gain more weight (+2.4%) than the 3PF pigs, mainly because of faster growth (P=0.02) during the first feeding period. At the end of the experiment, total body protein mass was similar in the two treatment groups, but the DPF pigs had 8% more body lipids (P=0.04) than the 3PF pigs. Daily multiphase feeding reduced N excretion by 12% (P<0.01) but did not significantly reduce P excretion. In addition, feed costs, nutrient intake and nutrient excretion under the two feeding strategies were simulated and compared after different approaches were used to formulate complete feeds for each phase of the 3PF system, as well as the two feeds used in the DPF program. Simulated feed intake and growth was similar to those observed in the animal experiment. In comparison with the simulated 3PF system, the feed cost for the DPF pigs was reduced by 1.0%, the simulated N and P intakes were reduced by 7.3% and 4.4%, respectively, and the expected N and P excretions were reduced by 12.6% and 6.6%, respectively.
The concomitant adjustment of the dietary concentration of nutrients to match the evaluated requirements of pig populations can be an efficient approach to significantly reduce feeding costs and N and P excretions in pig production systems.
Pomar, C., Pomar, J., Dubeau, F., Joannopoulos, E. and Dussault, J.-P. (2014). The impact of daily multiphase feeding on animal performance, body composition, nitrogen and phosphorus excretions, and feed costs in growing–finishing pigs. Animal, 8; 704-713.