Mastitis in cattle is called by

Options

A. virus
B. bacteria
C. protozoan
D. helminth

Answer

### Step-by-Step Solution:

1. **Understanding Mastitis**: The term "mastitis" refers to the inflammation of the mammary gland. The suffix "-itis" indicates inflammation, and "masto-" refers to the breast or mammary gland.

2. **Identifying the Cause**: Mastitis can occur due to various pathogens, including viruses, bacteria, protozoa, and helminths. However, in cattle, it is primarily associated with bacterial infections.

3. **Common Bacterial Strains**: The most common bacteria responsible for mastitis in cattle are:
- **Staphylococcus aureus**: This is a well-known bacterium that can cause various infections, including mastitis.
- **Corynebacterium**: Another type of bacteria that can also lead to mastitis.

4. **Conclusion**: Based on the information, mastitis in cattle is primarily caused by bacteria, specifically strains like Staphylococcus aureus and Corynebacterium.

### Final Answer:
Mastitis in cattle is caused by **bacteria**.

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