Most swine diets must be supplemented with calcium because most plant ingredients commonly used in diets for pigs contain relatively little calcium. One way to add calcium is to include inorganic sources such as dicalcium phosphate or calcium carbonate; however, animal ingredients such as meat byproduct meals can also be used. These ingredients, often used as a protein source, are also a good source of calcium. To our knowledge, values for apparent (ATTD) and standardized (STTD) total tract digestibility of calcium in animal sources have not been reported. Therefore, an experiment was conducted to determine the ATTD and STTD of calcium in four calcium sources of animal origin.

The secondary objective of the study was to test the hypothesis that the addition of microbial phytase to diets containing calcium sources of animal origin would increase the digestibility of calcium. Although animal sources do not contain phytate, swine diets are composed primarily of plant ingredients, and the phytate in those ingredients might form complexes with the calcium in the animal sources.

Rojas, O. J. and H. H. Stein. 2013. Concentration of digestible and metabolizable energy and digestibility of amino acids in chicken meal, poultry byproduct meal, hydrolyzed porcine intestines, a spent hen–soybean meal mixture, and conventional soybean meal fed to weanling pigs. J. Anim. Sci. 91:3220-3230. Link to full text (.pdf)

Rojas, O. J. and H. H. Stein. 2013. Concentration of metabolizable energy and digestibility of amino acids in chicken meal, poultry by-product meal, Ultrapro, AV-E Digest, and conventional soybean meal fed to pigs. J. Anim. Sci. 91(Suppl. 2):26 (Abstr.) Link to abstract (.pdf)

Protein sources of animal origin provide highly digestible protein in diets for weanling pigs. Chicken meal consists primarily of skin, flesh, and sometimes bones from processed birds. Poultry by-product meal contains offal from processed chickens, including  feet, necks, beaks, undeveloped eggs, and intestinal contents. AV-E digest consists of enzymatically hydrolyzed spent hens and extruded egg albumin, mixed with a soybean meal carrier. Ultrapro is produced from enzymatically hydrolyzed porcine intestines, which are used in the production of the drug heparin. There is a lack of data on the concentration of digestible and metabolizable energy in all of these ingredients, which limits their use in diets fed to weanling pigs.

An experiment was conducted to determine the concentrations of digestible and metabolizable energy in chicken meal, poultry by-product meal, Ultrapro, and AV-E digest, and to compare these values with soybean meal.