Effects of NaOH-treated wheat and a mixture of barley and oats on the voluntary feed intake and milk production in dairy cows

Abstract

An experiment was conducted to examine how including NaOH-treated wheat in the diet of dairy cows affects dry matter intake (DMI) and milk production, using diets based on rolled wheat and an oat/barley mixture for comparative purposes. The study was based on 24 Swedish Red dairy cows that were 147 +/- 51 d in milk (DIM), with an average milk yield of 31 +/- 5.6 kg/d and a live weight of 611 +/- 66 kg. The cows were blocked according to DIM and randomly assigned to six replicated 4 x 4 balanced Latin squares with 21-d experimental periods. The diets were fed as total mixed rations consisting of grass silage supplemented with concentrates in a ratio of 52:48. Four diets were examined: an oat/barley mixture (0BM), 100% rolled wheat (RW) of which 50 (SHW/RW) or 100% was replaced with NaOH treated wheat (SHW). Total tract digestibility was determined using acid-insoluble ash as an internal marker. Ruminal degradation parameters for the cereal feeds were estimated using an in vitro gas production technique and modelling approach. Increased inclusion of Na0H-treated wheat did not affect DMI or milk production. NaOHtreatment reduced (P<0.01) milk protein concentrations and milk N efficiency (P< 0.05),and tended (P=0.10) to decrease milk protein yield. There were no differences between the OBM and RW diets in terms of DMI, milk production, or milk composition. Increased levels of NaOH-treated wheat in the diet caused linear increases (P< 0.05) in faecal N output and estimated urinary volumes and decreasing milk urea concentrations. This indicates that NaOH-treatment increased the mineral load of the diet and shifted starch digestion from the rumen to the small and large intestines. These results were consistent with the lower observed in vitro ruminal digestion rates of NaOH-treated wheat. It is concluded that the oat/barley mixture and the rolled wheat had comparable feeding values despite the higher tabulated metabolisable energy and protein concentrations of the latter. It is concluded that NaOH-treatment of wheat has no beneficial effects that justify its use. (C) 2013 Elsevier B.V. All rights reserved.

Keywords

Alkali-treated grain; Digestibility Oat/barley mixture; Starch Urinary excretion

Published in

Livestock Science
2013, volume: 154, number: 1-3, pages: 103-111
Publisher: ELSEVIER SCIENCE BV

SLU Authors

• Hetta, Mårten

  • Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences
    

• Krizsan, Sophie Julie

  • Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences
    

• Huhtanen, Pekka

  • Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Agricultural Science

Publication identifier

• DOI: https://doi.org/10.1016/j.livsci.2013.03.015

Permanent link to this page (URI)

https://res.slu.se/id/publ/52650