Status of Piglets’ Cellular Immunity in the Early Postnatal Period

Abstract

The results of studying piglets' cellular immunity in the postnatal period in an industrial pig-farming system have been reported. It is ascertained that the cellular immunity in piglets before colostrum intake is characterized by leukocytopenia, lymphocytopenia, T- and B-lymphocyte deficiencies and high ratios of theophylline-resistant (T-helpers) to theophylline-sensitive (T-suppressors) T cells, indicating the low suppressive activity of T lymphocytes. In 1-day-old piglets after colostrum intake and during the whole period of their growing under the sows, the increased counts of white-blood cells and lymphocytes, the T- and B-lymphocyte absolute counts, and T-helper cells, along with a lower count of T-suppressor cells and low T-to-B-cell ratios, indicating the predominant mechanisms of specific cellular defense, were recorded. A reduction in the counts of white-blood cells, lymphocytes, and T- and B-lymphocytes in piglets on the 14th day of life, when compared to the parameters measured on the seventh day of life, is caused by the decline in these cell’s supply via sow milk. A subsequent increase is associated with the activation of the piglets’ own immune system function, whose development is dependent on the effects of microbial contamination within the mucous membranes and the skin.