Maternal transference of passive humoral immunity to Haemonchus contortus in goats

Maternal protein deficiency during a gastrointestinal nematode infection alters developmental profile of lymphocyte populations and selected cytokines in neonatal mice

Neonatal immune development begins in pregnancy and continues into lactation and may be affected by maternal diet. We investigated the possibility that maternal protein deficiency (PD) during a chronic gastrointestinal (GI) nematode infection could impair neonatal immune development. Beginning on d 14 of pregnancy, mice were fed protein-sufficient (PS; 24%) or protein-deficient (PD; 6%) isoenergetic diets and were infected weekly with either 0 (sham) or 100 Heligmosomoides bakeri larvae. Pups were killed on d 2, 7, 14, and d 21 and dams on d 20 of lactation. Lymphoid organs were weighed. Cytokine concentration in maternal and pup serum and in milk from pup stomachs and lymphoid cell populations in pup spleen and thymus were determined using luminex and flow cytometry, respectively. GI nematode infection increased Th2 cytokines (IL-4, IL-5, IL-13), IL-2, IL-10, and eotaxin in serum of dams whereas PD reduced IL-4 and IL-13. The lower IL-13 in PD dams was associated with increased fecal egg output and worm burdens. Maternal PD increased vascular endothelial growth factor in pup milk and eotaxin in pup serum. Maternal infection increased eotaxin in pup serum. Evidence of impaired neonatal immune development included reduced lymphoid organ mass in pups associated with both maternal infection and PD and increased percentage of T cells and T:B cell ratio in the spleen associated with maternal PD. Findings suggest that increases in specific proinflammatory cytokines as a result of the combination of infection and dietary PD in dams can impair splenic immune development in offspring.

Teladorsagia circumcincta antibodies in serum and milk samples in experimentally infected lactating ewes

The aim of this study was to evaluate the IgG activity in serum and milk samples of experimentally infected lactating ewes with the nematode Teladorsagia circumcincta as well as its relationship to the degree of infection. In a previous study 28 pregnant ewes were divided into two homogeneous groups, with high (H) and low (L) level of parasitism, respectively. Blood and milk samples were taken weekly after lambing until the end of the lactation, 126 days post-partum (pp). IgG against T. circumcincta were measured by means of an indirect ELISA. The kinetic of the immunoglubulins in serum samples showed a very low activity at the beginning but gradually increased throughout the lactation; H group showed higher values most of the sampled days than L group. Contrary, IgG in milk samples remained high during the first month pp, then decreased around 38% and by the end of the study rose again. Antibodies in both samples were correlated and especially during the second month of lactation (r=0.3; p<0.001). With the aim to correlate the immune response and the degree of infection we found an inverse relationship (r=-0.2; p<0.05) during the second month of lactation between eggs and IgG in serum. However the correlation with immunoglobulins in milk was positive, mainly, on the last third of lactation (r=0.2; p<0.01). As a conclusion, the individual detection of total IgG antibodies against T. circumcincta in lactating ewes is highly dependent on the stage of lactation. Therefore, these associations should be confirmed under field conditions.