27 Gestation stage and lactation impacts on nutrient retention in multiparous sows

Abstract Abstract: Introduction Understanding nutrient retention during gestation and lactation is important for understanding sow nutrient demands. Little information is available regarding nutrient retention of multiparous sows during these phases. Objective Assess nutrient apparent total tract digestibility (ATTD) days 40 to 44 and 96 to 100 of gestation and mid-lactation. Methods During the gestation collection periods, sows were housed in individual metabolism crates. Total feces and urine was collected. Titanium dioxide (TiO2) was used as an indigestible marker in lactation. The study used 48 parity 2 through 6 sows. Gestation and lactation diets contained 1,000 FTU/kg of phytase and 50 mcg/kg of 25-OH D3. Results The ATTD of DM, N, GE, fat, total and insoluble fiber were not different (P > 0.10) between stages of gestation but were lower in lactation than gestation (P < 0.001). Ash, Ca and P ATTD were greater in later gestation than early gestation (P < 0.001). Ash and Ca ATTD were lower in lactation than either stage of gestation (P < 0.05) with P ATTD being similar in early gestation and lactation. The ATTD of K (P < 0.05), Na and Mg (P < 0.001) were lower in lactation than gestation. Gestation Zn, Cu, Mn and Fe ATTD were positive with no difference by stage of gestation (P > 0.10). Lactation ATTD of Zn, Cu, Mn and Fe was negative and significantly lower than during either stage of gestation (P < 0.01). Conclusion Late gestation appears to drive Ca and P retention while lactation appears to result in reduced Ca retention and net loss of Zn, Cu, Mn and Fe.