The Claim
In cattle, increasing dietary beta-carotene from 0 to 352 mg/kg dry matter intake raises 15,15'-dioxygenase enzyme activity in the duodenum from 0.19 to 0.45 nmol retinal/(mg S-9 protein/h), and this activity remains lower than in goats at all doses.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When cattle are fed more beta-carotene, their duodenal enzyme activity that converts beta-carotene to retinal increases from 0.19 to 0.45 nmol retinal per mg S-9 protein per hour, but this activity is consistently lower than in goats under the same feeding conditions.
See the scientific wording
In cattle, increasing dietary beta-carotene from 0 to 352 mg/kg dry matter intake raises 15,15'-dioxygenase enzyme activity in the duodenum from 0.19 to 0.45 nmol retinal/(mg S-9 protein/h), but activity remains lower than in goats at all doses.
When cattle eat more beta-carotene, their gut enzyme that breaks it down becomes more active, but it still works much slower than in goats. This means less of the beta-carotene turns into retinal, so more of it stays in the body and colors the fat yellow.
What the research says
1 studyWhen cows eat more beta-carotene, their gut enzyme that breaks it down works a little harder, but it still works much slower than the same enzyme in goats. This is exactly what the study found.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.