Related Experiment Videos
Free and total ion concentrations in pig digesta
F R Dintzis1, J A Laszlo, T C Nelsen
1National Center for Agricultural Utilization Research, ARS, USDA, Food Physical Chemistry, Peoria, IL 61604, USA.
Journal of Animal Science
|April 1, 1995
Summary
Understanding mineral bioavailability requires differentiating between total and free ion concentrations in the gastrointestinal tract. Mineral supplementation did not change the free:total ratios, but increased free calcium, zinc, and copper levels in specific areas.
Area of Science:
- Animal Nutrition
- Mineral Metabolism
- Gastrointestinal Physiology
Background:
- Mineral bioavailability is crucial for animal health and is influenced by the concentration of free ions in the digesta.
- Distinguishing between total and free mineral ion concentrations is essential for accurate bioavailability assessments.
Purpose of the Study:
- To quantify and compare free and total cation concentrations in pig digesta across different gastrointestinal locations.
- To investigate the impact of dietary mineral supplementation (Ca, Zn, Fe, Cu) on free ion concentrations.
- To assess the role of corn bran fiber in mineral absorption and bioavailability.
Main Methods:
- Determined free and total cation concentrations in pig digesta using a 1,000 molecular weight cutoff filter.
- Analyzed Ca and K content in corn bran fragments via energy-dispersive X-ray analysis.
- Compared mineral concentrations and free:total ratios between pigs fed basal and supplemented diets.
Main Results:
- Free cation concentrations varied significantly, with Na and K being highly soluble, while Ca, Zn, Fe, and Cu showed lower free percentages.
- Free:total cation ratios for Ca, Mg, Zn, and Cu differed between upper and lower gastrointestinal tract regions.
- Dietary mineral supplementation did not alter the free:total ratios but increased overall mineral concentrations and free Ca, Zn, and Cu in specific segments.
Conclusions:
- The study highlights the importance of considering free ion concentrations for understanding mineral bioavailability in pigs.
- Corn bran did not show preferential mineral absorption, suggesting other factors influence bioavailability.
- While supplementation increased total and some free mineral levels, the fundamental free:total ratios remained largely unaffected by dietary changes.