The relationship between concentrations of vitamin D-binding protein (DBP) in serum and colostrum of mares and in serum of their foals in the neonatal period.

Vitamin D-binding protein (DBP) participates in the actin scavenger system, it is a carrier of vitamin D and its derivatives, it manifests the capacity to bind mainly monounsaturated and saturated fatty acids, it binds to the surface of several cells and enhances chemotactic activity of C5a of the complement. The present study was aimed at answering the question whether serum DBP level in mares is related to levels of this protein in colostrum and in serum of its progeny. For this purpose, sera from 77 mares, colostra from 72 mares and sera from 69 Thoroughbred foals were collected. Mother's age, number of deliveries experienced in the past, month of delivery, feeding of foals with colostra were recorded. Blood of the foals was sampled from the umbilical vein during delivery (0h) and 36-48 h after delivery from the external jugular vein, colostra of the mares were obtained after delivery and blood of the mares was sampled 36-48 h after delivery. Concentration of DBP was estimated by a self-designed ELISA. In the present study, DBP concentrations in newborn's serum were found independent of their concentrations in mother's serum, her age and number of parities experienced in the past. Colostrum DBP level was found to be lower than that in the mare's serum and was not correlated to the concentration of this protein in mare's serum. There was no effect of colostrum feeding on DBP level in the foal serum. These results indicate that serum DBP concentration in newborn foals depends on factors which act directly on the foal. Because of the lack of correlation between plasma and colostrum concentrations of DBP, it can be assumed that DBP is synthesised in the mammary gland and/or specific transport mechanisms exist in the mammary gland.

Transfer of maternal passive immunity to kids in goat herd.

The efficiency of tranfer of maternal immunity and its infuence on the kids' health was observed in a herd in which kids (n=20) had whole contact with the dam (n=13). The factors associated with dam, kid and human, which influence the efficiency of passive transfer were observed. It was estimated that the single-born kids reached higher serum gamma-globulin level (mean 23.14 g/dm3) than twin kids (mean 18.2 g/dm3) (p < 0.05). The gamma-globulin level was the highest in single-born kids at 48 h, and in twin kids in 24 h of life. The IgG class antibodies to herd-homologous strains of Pasteurella multocida and Escherichia coli were estimated using ELISA in sera, colostrum and milk whey samples of dams and sera of kids. It was found that maternal antibodies specific to these two facultative pathogens decreased in kids sera rapidly and the self humoral immune response occurred within the period of observation. Two kids delivered by goats with lowest hierarchic position in the herd showed failure of passive transfer, and died at the 10th and 12th weeks of life due to chronic infections induced by both above mentioned bacterial strains.

Enhanced tumor necrosis factor-alpha production following endotoxin challenge in rats is an early event during magnesium deficiency.

Magnesium (Mg) plays an essential role in fundamental cellular reactions and the importance of the immuno-inflammatory processes in the pathology of Mg deficiency has been recently reconsidered. The purpose of the present study was to assess the effect of different stages of Mg deficiency on endotoxin response and tumor necrosis factor-alpha (TNF alpha) production. Weaning male Wistar rats were pair fed either a Mg-deficient or a control diet. At day 7, lipopolysaccharide (LPS) induced no lethal effects in control rats but resulted in 70% mortality in Mg-deficient rats within 3 h. The vulnerability of Mg-deficient rats to LPS was associated with higher TNF alpha plasma values. Mg-deficient animals that received magnesium supplementation before endotoxin challenge had significantly increased survival. At day 2, control and Mg-deficient rats were also subjected to endotoxin challenge with or without magnesium pre-treatment. A significant increase in TNF alpha plasma level was observed in Mg-deficient rats compared to rats fed the control diet. Mg-deficient rats that received magnesium replacement therapy before endotoxin challenge had significantly lower TNF alpha plasma values than those receiving saline before endotoxin. Thus, the results of this experiment suggest that the activated or primed state of immune cells is an early event occurring in Mg deficiency.

Immunoglobulins of colostrum--VI. Comparative studies of cytophilic properties of bovine serum and colostral IgG.

In our previous studies, using physical-chemical and serological methods, substantial differences between bovine serum and colostral IgG, especially IgG2, have been shown. The structural differences were localized in the Fc region of immunoglobulins studied. The present comparative studies were undertaken to determine whether structural differences in the Fc region of bovine serum and colostral IgG are reflected in the interaction of these immunoglobulins with the guinea-pig peritoneal macrophage Fc gamma receptor. It was found that binding of bovine serum and colostral IgG1 was a saturable process and only quantitative differences in the mode of binding to the Fc receptor were observed. There is, however, a big difference in cytophilic activity of bovine IgG2--no saturable and reversible binding is observed in the case of bovine serum IgG2.