Breast fed baby is protected from some GI infection due to presence of what in mothers milk: March 2013
**Core Concept**
The presence of certain immunoglobulins in breast milk provides protection to the infant against gastrointestinal infections. This concept is related to the transfer of maternal antibodies to the infant through breast milk, which helps to confer immunity against various pathogens.
**Why the Correct Answer is Right**
The correct answer is related to the presence of secretory immunoglobulin A (sIgA) in breast milk. sIgA is the primary immunoglobulin in breast milk, accounting for up to 80% of the total immunoglobulin content. It plays a crucial role in preventing the attachment and invasion of pathogens to the epithelial lining of the infant's gut, thereby providing protection against gastrointestinal infections. The presence of sIgA in breast milk also helps to stimulate the infant's immune system to produce antibodies against specific pathogens.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the correct answer is related to immunoglobulins, not enzymes.
* **Option B:** This option is incorrect because lactoferrin is an iron-binding protein found in breast milk, which has antimicrobial properties, but it is not the primary immunoglobulin responsible for protecting against gastrointestinal infections.
* **Option C:** This option is incorrect because lysozyme is an enzyme found in breast milk that has antimicrobial properties, but it is not the primary immunoglobulin responsible for protecting against gastrointestinal infections.
**Clinical Pearl / High-Yield Fact**
Breast milk contains a range of immunoglobulins and other bioactive molecules that provide protection to the infant against various pathogens. The presence of these molecules in breast milk is an important factor in the development of the infant's immune system.
**Correct Answer: B. Lactoferrin.**