Patrycja Schulz

Influence of nematode Anguillicoloides crassus infestation on the cellular and humoral innate immunity in European eel (Anguilla anguilla L.).

Parasitic invasions are recognized as one of the primary factors responsible for decreasing populations of European eel. The aim of the present study was to determine the influence of infestation with the nematode Anguillicoloides crassus on the innate immunity in European eel (Anguilla anguilla). Anguillicoloides crassus parasitizes the swim bladder of this fish. Levels of the following immunological parameters were measured: spleen phagocyte respiratory burst activity, spleen phagocyte potential killing activity, pronephros lymphocyte proliferation stimulated by concanavaline A or lipopolisaccharide, plasma lysozyme and ceruloplasmin activity, total protein and immunoglobulin (Ig) serum levels. The analyses of the results of humoral and cellular immunity indicate that all studied parameters were statistically significant higher (p < 0.05) in non-infested fish compared to the ones with anguillicolosis except for ceruloplasmin level. These data suggest that the A. crassus infestation in European eel is responsible for a decreased immune response what could result in higher susceptibility to other pathogenic conditions.

Influence of β-glucan Leiber ® Beta-S on selected innate immunity parameters of European eel (Anguilla anguilla) in an intensive farming system

Nutritional support plays an important role in promoting high cellular and humoral innate immunity activity and in preventing outbreaks of disease. The effects of β-glucan Leiber®Beta-S dietary supplementation on selected nonspecific immune parameters in juvenile European eel (Anguilla anguilla) in an intensive culture system were studied. The fish were fed commercial pellets containing either 0 (control group) or 200 mg Leiber®Beta-S kg-1 of feed (glucan-fed group). After four and eight weeks of feeding, the levels of the following immunological parameters were measured: phagocyte respiratory burst activity, phagocyte potential killing activity, lymphocyte proliferation stimulated by concanavaline A or lipopolysaccharide, serum lysozyme activity, and total immunoglobulin (Ig) serum levels. After four and eight weeks of feeding 200 mg Leiber®Beta-S kg feed-1 the levels of all immune parameters were statistically significantly higher (p < 0.05) in the glucan-treated group than in the control group. After eight weeks of feeding the fish 200 mg Leiber®Beta-S kg feed-1 and after an additional eight weeks in ponds, the levels of all immune parameters, excluding lymphocyte proliferation stimulated by concanavaline A, were statistically significantly higher (p < 0.05) in the glucan-fed group than in the control group. These data suggest that feeding juvenile eel Leiber®Beta-S for four and eight weeks might improve innate immunity.

Influence of bacteriophages cocktail on European eel (Anguilla anguilla) immunity and survival after experimental challenge

Inland fishery belongs to those branches of animal production that use very large amounts of chemotherapeutics, in particular antibiotics. The accumulation of chemotherapeutic agents in bottom sediments is a direct threat to the aquatic environment and directly affects the condition and health of the fish. Finding a preparation that could be used both prophylactically to increase the resistance of fish and therapeutically in case of infection with pathogenic bacteria, without side effects for fish and aquatic environment could be a great solution to this problem. Our aim was to determine influence of BAFADOR® the new bacteriophage-based preparation on European eel immunity and survival after experimental challenge. Application of BAFADOR® increased total protein level, immunoglobulin level, lysozyme activity and ceruloplasmin level in European eel serum. Potential killing activity and metabolic activity of spleen phagocytes as well as pronephros lymphocyte proliferation of was higher compared to control. The preparation also reduced mortality after experimental infections with the pathogenic bacteria Aeromonas hydrophila and Pseudomonas fluorescens. Our results showed that preparation BAFADOR® is well tolerated by the fish organism causing stimulation of cellular and humoral immunity parameters and reduces the mortality of the European eel after experimental challenge.

The innate immunity of wild Eurasian beaver from Poland - present knowledge and the need for research

For the first time we tried to examine the basic parameters of innate immunity in beavers for developing the new methods of prevention against infectious diseases in different reintroduction and translocation programmes in Poland. The aim of the present study was to determine the selected innate immunity parameters in Eurasian beavers living in natural conditions. The analyses of the results showed that the phagocytic ability (RBA) and potential killing activity (PKA) of blood phagocytes were higher in adult beavers compared to the young animals. The similar pattern was observed in proliferative response of blood lymphocytes stimulated by mitogens Concanavalin A (Con A) and lipopolysaccharides (LPS). The highest proliferative response in adult Eurasian beavers was observed. The ceruloplasmin activity in plasma was on similar levels in adult and young Eurasian beavers. The results of humoral mediated immunity showed that the lysozyme activity, total protein and gamma-globulin levels in serum were higher in adult beavers compared to the young beavers. The results of this preliminary study are important in comparative and clinical immunology.