Acta Veterinaria 18. (1968)
3. szám - SIMONYI ERZSÉBET - BOGNÁR KÁROLY - BIRÓ JENŐ - PALATKA ZOLTÁN: Immunization experiments against bovine viral diarrhoea. I. The production and application of hyperimmune serum
Acta Veterinaria Academiae Scientiarum Hungaricae Tomus 18 (3), pp. 237—243 (1968) IMMUNIZATION EXPERIMENTS AGAINST BOVINE VIRAL DIARRHOEA I. THE PRODUCTION AND APPLICATION OF HYPERIMMUNE SERUM By Erzsébet Simonyi, K. Bognár, J. Biró and Z. Palatka State Institute for the Control of Veterinary Serobacteriological Products (Director: Erzsébet Simonyi) and Phylaxia State Serum Institute (Director: J. Molnár), Budapest (Received August 29, 1967) In 1946 Olafson et al. described a new calf disease under the name bovine viral diarrhoea. In the meantime numerous reports have been published in all parts of the world on diseases of various mucous membranes of cattle. For a long time this group of disease has been referred to as bovine mucosal disease complex. The extensive application of tissue culture methods has promoted a closer investigation of this problem. It has been shown that in the aetiology of the disease complex several viral agents play a role. One of them is the causative agent of bovine viral diarrhoea (BVD), a calf disease causing the greatest losses among cattle both in Hungary and abroad. In Hungary, incidence of BVD was observed first by Manninger et al. (1963), who demonstrated its identity with the condition described abroad. Another Hungarian paper (SÁLYI and Kardeván, 1964) dealt with the pathology of the disease. An epidemiological analysis revealed the extensive occurrence of BVD also in this country as well as its severe economic damages, particularly in calf rearing farms (Rom- VÁRY, 1964a, b). Economic losses have considerably increased with the development of large-scale cattle farming. Incidence of BVD in a calf herd causes losses not only by mortality, but also by growth retardation and faulty development of the surviving animals. In our country, so far no specific control measures have been applied against BVD. To minimize losses, besides symptomatic treatment, improvement of feeding and management conditions has been suggested in order to improve the natural resistance of the young animals (Romváry, 1964a, b). Nevertheless, certain shortcomings of intensive farming could not yet be eliminated and as BVD has continued to spread and cause relevant losses, the elaboration of specific control measures has become necessary (Simonyi et al., 1965). Foreign authors have recommended the application of broad-range antibiotics, e.g. tetracyclines, for the symptomatic treatment of BVD. Möhlmann (1965) has suggested the use of gamma globulin, whereas Mayr (1965) the use of preparations, particularly of foreign proteins, which are apt to increase the non-specific resistance of calves. As a specific measure against BVD, certain authors give preference to active immunization, since in other countries BVD affects chiefly calves above 6 months of age. As to active immunization of young animals, several authors (Fey, 1964; Fey and Hunyadi, 1962; Mayr et al., 1964, 1965) have agreed in that it is useless owing to the physiological absence of immune globulins in newborn calves. Immunization of day-old calves may even give rise to immunological tolerance. The last cited authors have recommended the application of stable-specific colostrum, i.e., the enhancement of colostral immunity by vaccination of the mother animals. Since in newborn animals the intestinal absorption of antibodies may be depressed, they suggest the parenteral administration of colostrum-serum or of gamma globulin extracted from colostrum or blood serum. Fey and Hunyadi (1962) have found favourable results with the intravenous application of 50 — 100 ml colostrum-serum. With this method also Bürki and Germann (1964) have successfully cured calves infected with serious BVD. Examining the protective effect of collecl- Acta Veterinaria Academiae Scientiarum Hungaricae 18, 1968 2