The immunoglobulin abundant in colostrum is
or
The yellowish fluid colostrum has abundant antibodies to protect the infant

Options

A. IgG
B. IgA
C. IgM
D. IgE

Answer

**Step-by-Step Solution:**

1. **Understanding Colostrum**: Colostrum is the first form of milk produced by mammals immediately following the delivery of the newborn. It is a thick, yellowish fluid that is rich in antibodies and nutrients.

2. **Identifying Immunoglobulins**: There are different types of immunoglobulins (antibodies) in the human body, namely IgG, IgA, IgM, and IgE. Each type has a specific role in the immune system.

3. **Role of IgG**: IgG is the most abundant immunoglobulin in the bloodstream and provides immunity to the fetus during pregnancy. However, it is not the primary antibody found in colostrum.

4. **Role of IgA**: IgA is primarily found in mucosal areas, such as the gut, respiratory tract, and urogenital tract. It plays a crucial role in mucosal immunity and is abundant in colostrum, helping to protect the infant's mucous membranes.

5. **Role of IgM**: IgM is the first antibody produced in response to an infection. It is not specifically abundant in colostrum.

6. **Role of IgE**: IgE is involved in allergic reactions and responses to parasitic infections. It is not related to the antibodies present in colostrum.

7. **Conclusion**: Based on the information about the different immunoglobulins, the immunoglobulin that is abundant in colostrum is IgA. It provides essential protection to the infant during the initial days of life.

**Final Answer**: The immunoglobulin abundant in colostrum is IgA.

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