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Increasing fat deposition and feed conversion ratio over the days in finishing phase directly influence pork quality and productive profitability. Nonetheless, the slaughter of heavier pigs can result in benefits for the slaughterhouse due to dilution of production and processing costs, as well as economic benefits for the pig producer resulting from the dilution of production costs. Therefore, dietary supplementation of chromium for finishing pigs of high lean-genotypes is a strategy to increase lean tissue accretion and minimize fat deposition, reflecting positively on growth performance. This review discussed recent studies results and mechanisms of action of this modifier of performance and carcass a traits in finishing pigs. Chromium increases the insulin action, facilitating insulin binding to the receptors on cell membrane. As a result, insulin-sensitive cells uptake more glucose, which will be later converted into energy. This additional energy is use to increase protein synthesis, thereby increasing the amount of lean tissue and reducing fat content in the carcass, without altering protein intake by pigs. Chromium also reduces lipid oxidation rate maintaining meat quality for longer period. In conclusion, dietary Cr supplementation for finishing pigs have shown that 0.2 mg/kg of organic Cr sources for pigs from ~60 kg until the slaughter can improve growth performance, lean gain and reduce fat content in carcass. However, the development of nanotechnology has allowed the use of inorganic Cr source at 0.2 mg/kg of inclusion, leading to improve the growth performance and carcass traits of finishing pigs.

To evaluate the effects of temporary dietary lysine restriction on nursery pigs’ growth performance and its economic viability compared to control diets, 144 piglets (21-d-old) were assigned to randomized blocks, with two treatments and twelve replicates. The treatments were control-lys: lysine level as recommended from 21-32 and 32-42 days and low-lys: 90% of the lysine level of the control-lys diets. From 42 to 62 days, all animals received a control diet. From 21 to 32 days, pigs fed low-lys had worse average daily gain (ADG), feed conversion, and 32-d body weight (BW; P ≤ 0.05). From 32 to 42 days, pigs fed low-lys had lower average daily feed intake, ADG, and 42-d BW (P ≤ 0.05). From 42 to 62 days, pigs had similar performance (P > 0.05). Overall (21 to 62 days), pigs fed the low-lys had lower (P <0.05) ADG and final BW. At 27 and 29 days, pigs fed the low-lys diet had a higher (P≤0.05) incidence of diarrhea. The lowest feed cost and the highest economic efficiency index were recorded for the low-lys treatment. However, pigs fed the control-lys presented a 3.9% higher profitability. In conclusion, a temporary reduction of lysine in the diets of nursery pigs followed by an unrestricted diet in the subsequent period led to worse growth performance and lower economic viability.