Abstract
It is of important methodological considerations to understand how the small intestine would respond to feeding of a series of assay diets deficient in gradient levels of phosphorus (Pi) associated with corn in growing pigs by the regression analysis technique (TRAT). A total of 48 barrows, with an average initial BW 32 kg, were randomly assigned to 6 grower pig diets and were fed close to ad libitum for 10 d, with 8-d adaptation and 2-d collection fecal samples, according to a randomized complete block design. Six cornstarch-based diets, containing 6 levels of Pi at 1.3, 1.9, 2.0, 3.6, 3.4 and 4.0 g/kg DMI, were formulated from corn. The gut permeability marker of D-mannitol was fed 0.30 g/kg BW at 4 h, prior to be sacrificed for sampling. ADG and the apparent ileal DM digestibility were linearly affected (P < 0.05); however, the ADFI, feed conversion ratio, the apparent fecal DM digestibility, transcellular gut permeability and the jejunal alkaline phosphatase kinetics were not affected (P > 0.05) by the increasing dietary levels of corn inclusion. There were linear relationships (P < 0.05), expressed as g/kg DMI, between the apparent ileal and fecal digestible Pi and the total intake of dietary Pi, suggesting that true ileal and fecal Pi digestibility (33.3±4.7 vs. 52.7±3.8%); and the endogenous Pi outputs (0.37±0.12 vs. 0.60±0.09, g/kg DMI) associated with corn could be estimated by the TRAT. Our results have shown that the intestinal physiological functions were not affected in the grower pigs fed on a series of test diets that were deficient in gradient levels of multiple assay nutrients, including macro-minerals, crude protein and amino acids supplied from the testing corn, for a period of 10 d, in the determination of corn-specific true digestibility and the endogenous outputs of Pi by the TRAT.
Accumulation of Insensitive Munitions Compounds in the Earthworm
Eisenia andrei
from Amended Soil – Methodological Considerations for Determination of Bioaccumulation Factors
