Contrasting effects of high-starch and high-sugar diets on ruminal function in cattle

Francesio, A., Viora, L. , Denwood, M. J., Tulley, W., Brady, N., Hastie, P. , Hamilton, A., Davison, C., Michie, C. and Jonsson, N. N. (2020) Contrasting effects of high-starch and high-sugar diets on ruminal function in cattle. Journal of Dairy Research, 87(2), pp. 175-183. (doi: 10.1017/S002202992000031X) (PMID:32314683)

Abstract

The experiment reported in this research paper aimed to determine whether clinical and subclinical effects on cattle were similar if provided with isoenergetic and isonitrogenous challenge diets in which carbohydrate sources were predominantly starch or sugar. The study was a 3 × 3 Latin square using six adult Jersey cows with rumen cannulae, over 9 weeks. In the first 2 weeks of each 3 week experimental period cows were fed with a maintenance diet and, in the last week, each animal was assigned to one of three diets: a control diet (CON), being a continuation of the maintenance diet; a high starch (HSt) or a high sugar (HSu) diet. Reticuloruminal pH and motility were recorded throughout the study period. Blood and ruminal samples were taken on day-1 (TP-1), day-2 (TP-2) and day-7 (TP-7) of each challenge week. Four clinical variables were recorded daily: diarrhoea, inappetence, depression and ruminal tympany. The effects of treatment, hour of day and day after treatment on clinical parameters were analysed using linear mixed effects (LME) models. Although both challenge diets resulted in a decline in pH, an increase in the absolute pH residuals and an increase in the number of minutes per day under pH 5.8, systemic inflammation was only detected with the HSt diet. The challenge diets differentially modified amplitude and period of reticuloruminal contractions compared with CON diet and both were associated with an increased probability of diarrhoea. The HSu diet reduced the probability of an animal consuming its complete allocation. Because the challenge diets were derived from complex natural materials (barley and molasses respectively), it is not possible to assign all the differential effects to the difference in starch and sugar concentration: non-starch components of barley or non-sugar components of molasses might have contributed to some of the observations. In conclusion, substituting much of the starch with sugar caused no substantial reduction in the acidosis load, but inflammatory response was reduced while feed rejection was increased.

• Item Type: Articles
• Additional Information: The work was partially funded by the Biotechnology and Biological Research Council, UK (Industrial Partnership Award BB/J016373/1, BB/J016608/1 and BB/J018120/1).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Hastie, Professor Peter and Jonsson, Professor Nicholas and Denwood, Dr Matthew and Francesio, Andrea and Brady, Mrs Nicola and Viora, Dr Lorenzo
• Authors: Francesio, A., Viora, L., Denwood, M. J., Tulley, W., Brady, N., Hastie, P., Hamilton, A., Davison, C., Michie, C., and Jonsson, N. N.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Journal of Dairy Research
• Publisher: Cambridge University Press
• ISSN: 0022-0299
• ISSN (Online): 1469-7629
• Published Online: 21 April 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Journal of Dairy Research 87(2): 175-183
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
167846		Sub-acute and acute ruminal acidosis; an interdisciplinary approach to understand and prevent a multifactorial disease.	Nicholas Jonsson	Biotechnology and Biological Sciences Research Council (BBSRC)	BB/J018120/1	Institute of Biodiversity, Animal Health and Comparative Medicine