Phosphorus (P) is an expensive component in swine diets, and dietary P levels above the pig's requirement can result in excess P excreted in manure and potential environmental concerns. Consequently, utilization of dietary P by pigs must be optimized in order to minimize diet cost and P excretion in manure. Phosphorus and calcium (Ca) balance was evaluated in nursery pigs fed a control maize-soybean meal (M-SBM) diet formulated on a total P (TP) basis, and four experimental diets containing maize dried distillers grains with solubles (DDGS; 100 or 200. g/kg) formulated on either a TP or available P (AP) basis. Barrow pigs (n= 39, initial body weight = 10.37 ± 0.37. kg) were randomly assigned to one of five diets for a 7. d adaptation period followed by a 5. d period of total, separate collection of both urine and feces. Compared to the M-SBM diet, dry matter (DM) digestibility coefficients were reduced in pigs fed diets containing 100 or 200. g/kg DDGS by approximately 0.02 and 0.04 units, respectively (P<0.01). Feed and total P intake were similar among pigs fed control and DDGS diets, but P intake was lower (P<0.01) for pigs fed diets formulated on an AP compared to TP basis. Fecal P concentration was reduced (P<0.01) when diets contained DDGS compared to the M-SBM diet, and when DDGS diets were formulated on an AP basis compared to a TP basis. Total P excretion, retention, and apparent total tract digestibility coefficients were not affected by diet formulation method (FM) or level of DDGS inclusion (P>0.05). Calcium intake tended to be higher (P=0.06), and fecal Ca concentration and retention were higher (P<0.05) for pigs fed the M-SBM diet compared with those fed the DDGS diets. Feeding the 200. g/kg DDGS diets tended to increase (P=0.08) fecal Ca excretion, and reduced (P<0.05) Ca retention, retention coefficient, and apparent total tract digestibility compared to feeding the 100. g/kg DDGS diets. There were no significant effects of FM or DDGS × FM for Ca intake, retention, excretion, or apparent total tract digestibility. These results indicate that increasing dietary DDGS inclusion levels for nursery pigs decreases DM digestibility and fecal P concentration, but does not affect P excretion, retention, or digestibility. Formulating DDGS diets (100 or 200. g/kg) on a TP or AP basis had no effect on P digestibility or total excretion, but total dietary P content is reduced when diets are formulated on an AP basis.
- Dried distillers grains with solubles
- Nursery pig
- Nutrient digestibility