Topics:
Animal Nutrition, Animal Refresher
Effects of Ionophores on Fermentation
Which of the following is an effect of monensin & lasalocid on rumen fermentation?
- They increase ruminal propionate & decrease ruminal acetate concentration so it decrease Acetate:Propionate ratio
- Decrease $CH_{4}$ production
- Inhibit biohydrogenation & Depress the activity of urease so less Ammonia is formed
- All are correct — Correct Answer
Explanation:
Correct Answer: All are correct
Ionophores (Monensin and Lasalocid) selectively inhibit Gram-positive bacteria in the rumen. This fundamentally shifts the rumen ecosystem to favour Gram-negative, propionate-producing bacteria, producing all the listed beneficial effects simultaneously.
Complete Effects of Ionophores on Rumen Fermentation
| Effect | Mechanism | Practical Benefit |
|---|---|---|
| ↑ Propionate, ↓ Acetate | Shifts fermentation toward Gram-negative succinate producers | Improved gluconeogenesis → higher milk sugar & body condition |
| ↓ CH₄ production | Less H₂ available (consumed by propionate pathway, not methanogenesis) | Reduced energy loss (CH₄ = 7% of GE intake in normal rumen) |
| Inhibit biohydrogenation | Suppress bacteria that hydrogenate unsaturated fatty acids | Higher unsaturated fatty acid content in milk fat |
| Depress urease activity | Fewer ureolytic bacteria → less NH₃ from dietary protein | Improved nitrogen utilization; less urea toxicity risk |
📚 About this Topic — Animal Nutrition
This multiple choice question is from Animal Nutrition, Animal Refresher. It has 4 options with a detailed explanation of the correct answer. Practice more MCQs from Animal Nutrition to strengthen your preparation.
