The bacterium that help in breakdown of cellulose in the rumen of cattle is

Options

A. Clostridium
B. Lactobacillus
C. Methanobacterium
D. Escherichia.

Answer

To answer the question regarding which bacterium helps in the breakdown of cellulose in the rumen of cattle, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Role of Bacteria in Rumen**: The rumen is a specialized stomach compartment in cattle that contains a diverse microbial population. These microbes play a crucial role in digesting cellulose, which is a major component of plant cell walls.

2. **Analyze Each Option**:
- **Clostridium**: This genus includes some pathogenic species that can cause diseases in cattle, such as clostridial abomasitis and enteritis. While they are involved in fermentation, they are not primarily known for cellulose breakdown.
- **Lactobacillus**: This is a beneficial bacterium that helps in lactic acid fermentation and can reduce methane production, but it is not specifically known for breaking down cellulose.
- **Methanobacterium**: This bacterium is found in the rumen and is involved in the fermentation process. It helps in the breakdown of cellulose, which is essential for the nutrition of cattle.
- **Escherichia**: While Escherichia coli is present in the intestines of cattle, it does not play a significant role in cellulose breakdown in mature cattle.

3. **Conclusion**: After analyzing all options, Methanobacterium is the bacterium that specifically aids in the breakdown of cellulose in the rumen of cattle.

### Final Answer:
The bacterium that helps in the breakdown of cellulose in the rumen of cattle is **Methanobacterium**.

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