Sodium and chloride are involved in numerous body processes, such as the sodium potassium pump and osmotic regulation. Typically, most diets for growing pigs contain a fixed amount of salt (0.35 to 0.50%) to meet the requirement estimate. However, this may result in exceeding concentrations of Na and Cl of the requirement estimate. A total of 1188 pigs (27 kg of initial BW) were used to determine the effects of additional salt on the growth performance of pigs. The trial lasted 44 d and approximately from 27 to 64 kg under commercial conditions. Pens were blocked by BW and randomly assigned to 1 of 4 dietary treatments in a completely randomized block design. There were 27 pigs per pen and 11 pens per treatment. The diets used were corn-soybean meal-based with 20% dried distillers grain with soluble and dietary treatments added salt containing either 0.10, 0.33, 0.55, or 0.75%, which resulted in calculated dietary Na levels of 0.10, 0.19, 0.28, and 0.36%; and calculated Cl levels of 0.23, 0.36, 0.49, and 0.61%.
Chemical analysis indicated that calculated values for Na and Cl were similar to analysed values. Sodium ranged from 0.11 to 0.34% and Cl ranged from 0.26 to 0.61%. From d 0 to 44, there was no evidence of difference to indicate that increasing salt beyond 0.10% influenced ADG, ADFI, FGR, or BW. In conclusion, 0.10% of added salt in a corn-soybean meal diet containing 20% dried distillers grain with solubles was adequate to maximize ADG, ADFI, and FG in 27 to 64 kg grower pigs.
Shawk, D.; Dritz, S. S.; Tokach, M. D.; Goodband, R. D.; Woodworth, J. C.; and DeRouchey, J. M. (2017) "Effects of Increasing Salt Concentrations on Growth Performance of Pigs Weighing 60 to 140 lb," Kansas Agricultural Experiment Station Research Reports: Vol. 3: Iss. 7. https://doi.org/10.4148/2378-5977.7486