The protective effects of breast milk are known to be associated with -

Ans. is `d' i.e., IgA antibodies Although antibodies and Lysozyme, both are impoant for protective effects of breast milk, antibodies play the major role. Out of IgM and IgA antibodies, breast milk is especially rich in secretory IgA which is the single best answer here. Protective role of breastfeeding against infection o Breast milk provides protection against infection because of the following facts ? 1. The breast milk is clean and uncontaminated 2. Breast milk contains several antiinfective factors - i) Antibodies secretory IgA, IgM ii) Lysozyme iii) Antistaphylococcal factor iv) Specific inhibitory substances against viral infections. v) Lactoferrin --> Inhibits growth of E. coli. vi) Bile stimulated lipase --> kills entamoeba histolytica and Giardia lamblia. vii) Bifidus factor -4 Inhibits growth of E. coli viii) Para-amino-benzoic acid (PABA) -3 Provides protection against malaria ix) Phagocytic macrophages and lymphoid cells 3. Lower pH of the stool of breastfed infants contributes to the orable intestinal flora ---> more bifidobacteri a and lactobacilli, fewer E. coli.