Which antibodies are abundant in colostrum ?

Options

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

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 typically yellowish in color and is rich in nutrients and antibodies.

2. **Identifying Antibodies**: The main antibodies present in colostrum are immunoglobulins. The most abundant antibody found in colostrum is Immunoglobulin A (IgA).

3. **Role of IgA**: IgA plays a crucial role in the immune defense of mucosal surfaces. It provides passive immunity to the newborn, as it is transferred from the mother to the infant through colostrum.

4. **Passive Immunity**: The transfer of IgA from mother to infant via colostrum is an example of natural passive immunity. This means the infant receives ready-made antibodies without its immune system having to produce them.

5. **Other Antibodies**: While other antibodies such as IgM, IgE, and IgG are important in the immune response, they are not abundant in colostrum. IgM is the first antibody produced by the body, IgE is involved in allergic reactions, and IgG is transferred from mother to fetus through the placenta.

6. **Conclusion**: Based on the information, the antibody that is abundant in colostrum is IgA.

**Final Answer**: The antibodies that are abundant in colostrum are Immunoglobulin A (IgA).

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