Influence of dietary cation–anion difference in finishing diets fed to Holstein steers during periods of high ambient temperature on feedlot performance and digestive function

Carlos Antonio Pacheco,Martin Francisco Montano-Gomez,Noemi Guadalupe Torrentera,Jaime Salinas-Chavira,Jose De Jesus Ortiz,Aris Bionel Cano,Ricard Avery Zinn

doi:10.1080/09712119.2017.1392311

Abstract

ABSTRACTOne hundred twenty-six Holstein steers (457.1 ± 27.5 kg BW) were used in a 127-d experiment to evaluate the influence of dietary cation–anion difference (DCAD) on growth performance and carcass characteristics. Treatments consisted of steam-flaked corn-based diets supplemented to provide DCAD of 34, 84 or 134 mEq/kg diet DM. There was no treatment effect (P > .20) on ADG, DMI, gain efficiency or dietary NE. Six Holstein steers (196 ± 3 kg) with cannulas in rumen and proximal duodenum were used in a replicated 3 × 3 Latin Square design to evaluated treatment effects on digestion characteristics. The DCAD did not affect (P > .20) ruminal or total digestion of OM, NDF, starch and N, or ruminal pH and VFA molar proportions. It is concluded that increasing DCAD of Holstein steers fed a conventional steam-flaked corn-based diet under conditions of high ambient temperature will not enhance growth performance.

Highlights

The anion–cation difference (DCAD) is represented as the possible negative or positive charge produced by nonmetabolizable dietary ion mixtures (Tucker et al 1988)
Diets formulated with dietary cation–anion difference (DCAD) of 250 mEq/kg DM have been recommended for optimal growth in chickens (Mongin 1981) and pigs (Austic and Calved 1981; Patience et al 1987), and 200–370 mEq/kg DM for optimal milk yield in lactating dairy cattle (Tucker et al 1988; West et al 1991)
Colgan and Mader (2007) evaluated effects of DCAD on ability of cross-bred yearling feedlot steers to cope with moderate summer heat stress during the final 67 d on feed

Summary

Introduction

The anion–cation difference (DCAD) is represented as the possible negative or positive charge produced by nonmetabolizable dietary ion mixtures (Tucker et al 1988). Increasing DCAD of dry rolled cornbased finishing diet from 91 to 294 mEq/kg did not affect ADG, DMI or gain efficiency. During periods of high ambient temperature characteristic of the desert Southwest (USA), DMI, and ADG and gain efficiency of Holstein steers are markedly depressed. This depression is most apparent during the late finishing phase (Torrentera et al 2017). The objective of this study was to evaluate the potential benefit of increasing DCAD in finishing diets on performance of Holstein steers when the late finishing phase coincides with the summer period of very high ambient temperature

Materials and methods

Results and discussion

Conclusion