Effects of inclusion of urea and wet distillers grains with solubles in diets based on dry-rolled corn on heifer performance and carcass characteristics

Abstract

Objectives

The objective of this study was to evaluate the effects of urea and wet distillers grains with solubles (WDGS) inclusion on heifer growth performance and carcass characteristics.

Materials and Methods

Crossbred heifers (n = 96) were used to study the effects of 2 inclusion levels of both WDGS and urea in a finishing diet based on dry-rolled corn on performance and carcass characteristics. Heifers were individually fed using a Calan gate system with a 2 × 2 factorial arrangement of treatments. Factors were inclusion of WDGS at either 10% or 20% of diet DM and dietary urea at a concentration of either 0.2% or 1.2% DM basis. Cattle were stratified by BW and assigned randomly to treatment. Blood samples were collected at 3 time points during the feeding period and analyzed for plasma urea nitrogen content. The statistical model included urea and WDGS inclusions and their interactions as fixed effects.

Results and Discussion

There were no interactions between WDGS and urea inclusion for any performance or carcass characteristics, so only main effects are discussed. There were no differences for final BW, ADG, and G:F on a live or carcass-adjusted basis for either urea or WDGS inclusion in the diet. Dry matter intake was less with increased urea inclusion; however, WDGS inclusion did not influence DMI. No differences were observed for any carcass characteristics because of urea or WDGS inclusion. Plasma urea nitrogen was greater for cattle as either urea or WDGS inclusion increased.

Implications and Applications

These data would suggest that when feeding diets based on dry-rolled corn, adding urea beyond that of the 0.2% treatment is not necessary when at least 10% WDGS is included in the diet