Topics:
Animal Physiology, Animal Refresher
Redox Potential of Reticulo-Rumen
Liquid phase of reticulo-rumen has an oxidation-reduction potential (redox potential) about-
- (−) 350 mV — Correct Answer
- (+) 350 mV
- (+) 500 mV
- (−) 500 mV
Explanation:
Correct Answer: (−) 350 mV
The liquid phase of the reticulo-rumen has a redox potential of approximately (−) 350 mV — indicating an extremely reducing (oxygen-free / anaerobic) environment.
What Does Negative Redox Potential Mean?
- A negative (reducing) redox potential = the environment is highly anaerobic (no free oxygen)
- Essential for survival of obligate anaerobic bacteria that drive fermentation
- Majority of ruminal bacteria are gram-negative obligate anaerobes
- Rumen metabolism is inhibited by oxygen — even small O₂ amounts disrupt fermentation (Q95 concept)
Exception — Lactic Acid Bacteria
- Lactic acid-producing bacteria (e.g., Streptococcus bovis, Lactobacillus) are facultative anaerobes
- They attach to the ruminal wall where trace O₂ may be present
- During high-grain feeding → lactic acid accumulates → ruminal acidosis
Rumen Ecosystem at a Glance
- pH: 6.5–6.8 | Temperature: 39°C | Redox: −350 mV | Gas: CO₂:CH₄ = 65:35 | VFA: Ace:Prop:But = 65:20:10 | VFA level: 80–120 mEq/L
📚 About this Topic — Animal Physiology
This multiple choice question is from Animal Physiology, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Physiology to strengthen your preparation.
