Alternative testing specimens
for Mammary Secretions
Neonates have an immature immune system that cannot adequately protect against infectious diseases. Early in life, maternal antibodies transferred from mother to offspring drive immune protection. In humans, maternal antibodies are mainly transferred before birth transplacentally. However, for animals of veterinary importance, lactogenic immunity remains the most promising and effective way to protect neonatal suckling animals from enteric diseases like enteric coronavirus or rotavirus. This is particularly true for domesticated animals like swine and cattle whose epitheliochorial placenta inhibits immunoglobulin (Ig) transfer in utero. Therefore, colostrum (first secretions from the mammary gland), and milk-derived antibodies and other immune factors are the sole source for immune protection after birth.
Passive lactogenic immunity is achieved through high titers of IgG antibodies in colostrum and a continuous supply of secretory IgA (sIgA) antibodies in milk. While colostral IgG antibodies are present in the bloodstream of the neonate in a finite amount that declines over time, IgA antibodies are continuously supplied through breast milk from the mother and protect the gastro-intestinal tract against pathogens in the same way as actively produced antibodies.