High-producing lactating sows can thrive using 15% distiller's dried grains with solubles (DDGS) to help meet their nutritional needs.
Equally important, adding phytase to these DDGS-supplemented sow lactation diets reduced phytate phosphorus excretion levels over sows fed conventional sow rations or a complete DDGS ration without phytase.
Two studies were completed using Yorkshire x Landrace sows nursing 11 or more pigs/litter, weaned at 18 days of age.
The first study compared sows fed 15% DDGS with sows fed 5% beet pulp (BP). The diets contained the same amount of fiber; lysine (1.2%); calcium (0.9%); and phosphorus (0.84%).
Treatment did not influence lactation performance. Sows weaned 10.9 and 10.8 pigs/litter with an average gain of 8.4 and 8.6 lb./pig for the BP- and DDGS-fed sows, respectively. Weight loss during lactation was 13.6 lb. (BP) and 17.9 lb. (DDGS). Fecal phosphorus excretion decreased linearly for DDGS-fed sows.
In the second study, a 15% DDGS sow lactation diet was compared with three other diet formulations. The trial included a control group (typical corn-soy diet); control group plus phytase, control group with 17% of phosphorus supplied by 15% DDGS; and this same DDGS diet plus phytase.
At 110 days of gestation, sows were gradually introduced to their lactation diet. Two days postfarrowing, litters were crossfostered to 11 pigs/litter, and sows and litters were weighed. Fecal grab samples were collected from 48 sows (12/treatment) on Day 7, 14 and 18 of lactation. Litter weight gain (101.2, 101.9, 92.6 and 92.8 lb.) and sow weight loss (17.8, 15.8, 15.4 and 13.9 lb.) were not affected by the respective dietary treatments.
The phosphorus concentration in the feces was similar between treatments on Day 7, 14 or 18, but was reduced in sows fed all treatments on Day 14 and 18.
Significantly, however, fecal phytate phosphorus (the form of phosphorus in corn and soybeans) was reduced in sows fed the DDGS-phytase diet at Day 14 and 18, vs. sows fed the three other diets.
Researchers: G.M. Hill, D.L. Kirkpatrick, J.E. Link, M.L. Gibson, K. Karges and M.J. Rincker, Michigan State University; and Dakota Gold Research Assn. Contact Hill by phone (517) 355-9676, fax (517) 432-0190 or e-mail hillgre@msu.edu.