The Study
Energy and roughage levels in cattle receiving diets and impacts on health, performance, and immune responses1.
This study didn't test anything new—it just looked at old experiments where scientists fed cows different foods and wrote down what happened. It says, 'When cows ate more grain, they grew faster but sometimes got sick more often.' But it doesn't prove the food made them sick—it just noticed a pattern.
Analysis score
Maximum 5 for a narrative review.
Where the score came from
When cows first arrive at feedlots, they’re switched from grass to grain. More grain helps them grow faster, but it can also make their stomachs too acidic, causing symptoms that look like a cold — so farmers think they have an infection and give them antibiotics.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 52 / 100
Quality score
Systematic reviews and meta-analyses of cohort studies. They sit above a single cohort study but below a single randomized trial, because the underlying evidence is still observational.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes — farmers face a real choice: feed more grain for faster growth (and risk over-treating healthy cows for acidosis) or feed less grain and accept slower growth.
- 2Cows fed diets with 1.10 Mcal NEg/kg DM gained weight well and stayed healthier.
- 3Above that, weight gain didn’t improve much, but sickness rates went up.
- 4Adding fibrous by-products like corn distillers grains helped reduce sickness.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of animal science
Year
2019
Authors
J. Richeson, K. Samuelson, D. Tomczak
Related Content
Claims (6)
Cattle raised in high-density environments with grain-based diets and hormonal treatments have higher rates of disease and receive antibiotics more frequently as a routine practice.
Feedlot cattle fed high-energy, low-roughage diets show higher weight gain and feed intake but also higher rates of illness, likely because the diet causes ruminal acidosis that mimics respiratory disease symptoms.
Replacing high-starch diets with fibrous by-products like corn distiller’s grains or wet corn gluten feed in cattle feeding improves rumen health and lowers acidosis risk while maintaining the same level of performance.
In feedlots, cattle with acute ruminal acidosis often show symptoms identical to those of bovine respiratory disease, leading veterinarians to incorrectly treat metabolic disorders as infectious diseases.
For newly arrived cattle, feeding diets with more than 1.10 Mcal NEg/kg dry matter does not reliably improve growth or health and may increase illness rates, suggesting there is a specific energy level that works best.
Feeding cattle direct-fed microbials like live yeast or Megasphaera elsdenii while on high-energy diets is linked to more stable rumen pH and better nutrient absorption, but the impact on their overall health and performance differs between studies.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.