Influence of grain processing in regard to serum metabolites and enzymes for finishing bull calves

C Castillo,P Vázquez,J Benedito,J Hernández,J Méndez,J Sotillo,V Pereira,A Suárez

doi:10.22358/jafs/66202/2011

Abstract

This study compared two grain processing methods that are widely used for beef cattle, grinding and steam pelleting, with respect to serum metabolic parameters: glucose, non-esterified fatty acids (NEFA), serum urea nitrogen (SUN), total serum protein (TSP), albumin, L-lactate, aspartate aminotransferase (AST), y-glutamyltransferase (GGT) and amylase. Ten Belgian Blue bull calves were allotted randomly to each of two experimental groups: PF, fed pelleted concentrate, and GF, fed ground concentrate. During the 77-day study most parameters underwent significant variation in time, increasing only numerically serum values of total protein, albumin, AST and amylase, while serum glucose, NEFA and GGT decreased numerically. Statistically significant differences were found only between groups PF and GF for creatinine (higher in group PF, in relation with its greater average body weight) and urea nitrogen, which for unknown causes fluctuated in opposite directions in the two groups throughout most of the study and attributable to changes in ruminai protein digestion. Neither serum glucose nor L-lactate were affected by treatment of grains.

Highlights

For high-output production, feedlot calves require a high-energy diet component such as starch, which is readily supplied in the form of cereal grains, of which it is a major component
Whole, unprocessed grains can be relatively indigestible. It is well-known that starch availability increases with processing grains, considerable differences have been detected between grain processing facilities (Brown et al, 2000)
Blood parameters indicate that, except for creatinine and the unexplained group×time interaction (G×T) interaction shown by the serum urea nitrogen (SUN) data, processing technique had no influence on the nutritional value of the ration

Summary

Introduction

For high-output production, feedlot calves require a high-energy diet component such as starch, which is readily supplied in the form of cereal grains, of which it is a major component. Whole, unprocessed grains can be relatively indigestible. It is well-known that starch availability increases with processing grains, considerable differences have been detected between grain processing facilities (Brown et al, 2000). The grain processing methods predominantly used in the production of Spanish cattle feeds are grinding and steam pelleting. Grinding destroys mechanical structure, exposing more starch to microbial digestion, but does not alter chemical structure. Steam pelleting increases moisture content, and disrupts the starch-protein matrix, which facilitates microbial and enzymatic access to starch granules (Dehghan-Banadaky et al, 2007)

Methods

Results

Discussion

Conclusion