ZINC, SELENIUM AND COPPER SUPPLEMENTATION THROUGH RETICULUM-RUMEN PELLETS AND ITS EFFECT ON THE RATE OF CELLULAR AND HUMORAL REACTIONS IN SHEEP

The objective of the study was to test the effectiveness of Zn, Se and Cu supplementation through reticulum-rumen pellets and its effects on the rate of cellular and humoral reactions in sheep. An experiment in cluded 12 lambing ewes of the Merino breed at the age of two years. Zn -containing pellets were applied via rumen to three lambing ewes at th e end of November, Se pellets were applied to other three lambing.ewes Cu pellets to other three ewes. Three lambing ewes were control. Bloo d samples were taken from the v. jugularis from all the investigated e wes before bolus administration, in month 1, 2, 3, 4, 6 and 7 after ap plication. Zn, Se and Cu concentrations in the blood serum were determ ined by atomic absorption spectrophotometry. Immune reactions were eva luated from the concentrations of serum immunoglobulins (IgC), albumin (ALB), total proteins (TP), from phagocytic activity (PA), phagocytic index (PI), migration-inhibitory test (MIT) and determination of tetr azolium-reductase activity of phagocytes (INT-test). In comparison wit h the starting values, the highest increase in zincemia (80 %) was rec orded in the lambing ewes administered zinc boluses as soon as in the lst month after administration. A significant difference in Zn concent rations between the zinc-pellet group and the control animals was obse rved in the 1st month after administration (P < 0.01). An increase in Se concentrations in the blood serum was observed in the lambing ewes administered selenium boluses in the lst month after administration. S e content in the blood serum of the given group of ewes was highest at the end of observation (2.72 +/- 0.29 mumol/l). A statistically signi ficant difference in Se content between the group of selenium-bolus ew es and the control ewes was confirmed at a significance level P < 0.05 in the 1st and 2nd month of the experiment. Cu concentrations in the blood serum in the Cu-bolus ewes increased in the 1st month if compare d with the starting values. The highest Cu concentration in the blood serum was recorded in the given group within month 4 to 7 of the exper iment (16.53 +/- 2.72, or 21.23 +/- 4.40 mumol/l). There were signific ant differences in cupremia between the Cu-pellet group of ewes and th e control animals (P < 0.05). In comparison with the starting values, the highest increase in TP concentrations were determined in the Cu-pe llet ewes in the 4th, 6th and 7th months. Albuminemia dynamics in the experimental animals and in the control group did mt vary significantl y. A trend of the highest immunoglobulinemia during the experiment was apparent in the ewes administered Se and Cu boluses. Significant diff erences in the concentrations of serum IgC between the groups of Cu-pe llet ewes and the control were recorded in the 4th, 6th and 7th months (P < 0.05, or P < 0.01) while between the Se-bolus animals and the co ntrol it was in the 6th month (P < 0.05). The experimental ewes had an insignificantly higher per cent of PA in the experiment. All the expe rimental groups had the statistically insignificantly higher PI in the 1st, 2nd, 6th and 7th months of observation in comparison with the co ntrol animals. After the polyclonal activation of ewe lymphocytes with phytohemagglutinin in MIT there was no significant difference in the migration index depending upon Se, Cu and Zn administration in compari son with the control group. The index of metabolic surge in the INT-te st had the highest values in the experiment in the ewes administered Z n-containing pellets. Significant differences in the index of metaboli c surge were confirmed between the Zn-pellet group of ewes arid the co ntrol animals in the 6th and 7th months (P < 0.05). The results of the experiments demonstrate the effectiveness of the tested reticulum-rum en boluses used in Zn, Cu and Se supplementation in ewes. The administ ration of these pellets can positively influence the animal immunity, which is advantageous particularly in the animals with a long-range de ficit of microelements.