The Study
Circadian Rhythm Enhances mTORC1/AMPK Pathway-Mediated Milk Fat Synthesis in Dairy Cows via the Microbial Metabolite Acetic Acid.
This study shows that in cows, certain gut bacteria and chemicals change at night, and these changes happen at the same time as higher milk fat. It doesn’t prove that one causes the other — just that they’re linked. Think of it like noticing ice cream sales and sunburns both go up in summer — they’re related, but one doesn’t necessarily cause the other.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
Cows make milk with more fat at night because their gut bacteria change and send more of a special acid into the blood. This acid helps turn on fat-making switches in the body.
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 56 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1This helps explain how a cow's daily rhythm affects milk quality, which could help farmers make better milk.
- 2At night, cows have more fat in their milk, more acetic acid in their blood, and certain bacteria and vitamin B6 go up in their stomachs.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Journal of agricultural and food chemistry
Year
2024
Authors
Xingwei Jiang, Huijun Geng, Chenguang Zhang, YuanYuan Zhu, Miaomiao Zhu, DingPing Feng, Dangdang Wang, J. Yao, Lu Deng
Related Content
Claims (5)
Cows might make fattier milk at night because their gut bacteria and body chemicals change with the time of day.
Acetic acid might help control how dairy cows make fat in their milk by turning certain genes on or off, depending on how much and how long they're exposed to it.
In dairy cows, a substance made by gut microbes (acetic acid) might affect milk fat by turning on certain cellular switches (mTORC1 and AMPK) that control fat-related genes.
When certain gut bacteria in cows are more active at night, it might help them make milk with more fat — kind of like how our body uses food differently depending on the time of day.
In dairy cows, vitamin B6 goes up in the stomach at night, and this might help move more acetic acid into the blood by turning on a protein called MCT1.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.