Calcium digestibility

Determination of endogenous intestinal losses of calcium and apparent and true total tract digestibility of calcium in canola meal fed to growing pigs

When formulating diets for pigs, it is more accurate to use values for standardized or true nutrient digestibility than values for apparent nutrient digestibility because the former are additive in mixed diets. No values for standardized or true total tract digestibility of calcium in pigs have been reported. The true total tract digestibility (TTTD) of a nutrient is calculated by correcting apparently total tract digestibility (ATTD) by total endogenous losses, which may be estimated using a regression procedure. To our knowledge, no measurements of the endogenous loss of calcium in pigs have been reported. An experiment was, therefore,  performed to measure endogenous loss of calcium and to determine TTTD of calcium in growing pigs, and to investigate if  the addition of microbial phytase to the diets affects TTTD of calcium. In addition, calcium retention was measured in pigs fed diets containing varying levels of calcium with or without microbial phytase.

Publication Type: 

Digestibility of phosphorus and calcium in meat and bone meal fed to growing pigs

Meat and bone meal (MBM) is a product of the rendering industry composed primarily of the offal and bones of slaughtered livestock, fat from unmarketable animal tissues, unsellable retail meat products, and whole condemned carcasses (excluding hair, blood, hooves, horns, and contents of the gastrointestinal tract).  MBM is traditionally used as an animal protein source in swine diets, but because of its high concentrations of calcium and phosphorus, it can also replace inorganic phosphates in swine diets.

The proportions of soft tissue and bone in different sources of MBM can vary widely. Because mineral digestibility differs in bone and soft tissue, the variation in composition of MBM sources leads to a variation in mineral digestibility values.

An experiment was conducted to 1) determine the apparent (ATTD) and standardized (STTD) total tract digestibility of phosphorus and the ATTD of calcium in 8 different sources of MBM,  2) estimate variation among MBM sources, and 3) develop equations to predict the concentrations of digestible phosphorus and calcium in MBM.

Publication Type: