Priprema, ispitivanje imunogenosti i ocena efikasnosti vakcine u profilaksi nastanka mastitisa kod krava

Abstract

Zapaljenje mlečne ţlezde, mastitisi krava, predstavljaju jedan od najaktuelnijih problema u intenzivnoj proizvodnji mleka, koji nanosi velike ekonomske gubitke. Dugogodišnji različiti pristupi lečenju subkliničkih i kliničkih mastitisa nisu dali zadovoljavajuće rešenje, pa je problem mastitisa i dalje aktuelan. Sprečavanje prodora patogenog uzročnika u mlečnu ţlezdu, njegovo naseljavanje i razmnoţavanje, nameću stalnu potrebu za redovnim kontrolama mleka, kao i preduzimanje preventivnih i terapijskih mera u cilju smanjenјa nastanka mastitisa. Stafilokoke mogu u akutnoj formi da izazovu teške, maligne mastitise, u vidu granulomatoznih i nekrotičnih promena. Hronične forme stafilokoknog mastitisa uglavnom prolaze kao subklinički oblici obolenja mlečne ţlezde. Najčešći prouzrokovači akutnog kataralnog mastitisa (mastitis catarrhalis acuta) su streptokoke (Streptococcus agalactiae, Streptococcus dysgalactiae i Streptococcus uberis), reĎe drugi mikroorganizmi. Javlja se neposredno posle telenja u periodu najveće mlečnosti. Ovi mikroorganizmi tokom vremena dovode do prestanka sinteze mleka. Stafilokoke, kao i streptokoke, su veoma slabi antigeni, što dodatno oteţava pronalazak efikasne vakcine. Iz tih razloga još uvek nije pronaĎena komercijalna efikasna vakcina protiv mastitisa izazvanih bakterijama S. aureus i Str.agalactiae, ali primena autohtonih vakcina u preveniranju mastitisa moţe dati zadovoljavajuće rezultate. Opisane su inaktivisane vakcine koje se sastoje od celih ili delova bakterijskih ćelija i njihovih toksoida. U pravljenju vakcina protiv mastitisa izazvanog S. aureus-om novina je dodavanje proteina A i fibronectin-binding proteina kao celularnih antigena. Sasvim nov pristup imunizaciji mlečne ţlezde predstavlja inkorporacija lizata S. aureus u biorazgradive partikule koje imaju funkciju da stimulišu produkciju i opsonizaciju antitela. Uzimajući u obzir rezultate drugih istraţivača i sopstvena preliminarna istraţivanja, a imajući u vidu problem koji predstavljaju mastitisi izazvani bakterijama Staphylococcus aureus i Streptococcus agalactiae, cilj istraţivanja je bio priprema i ispitivanje vakcine čija bi se efikasnost ogledala u smanjenju nastanka kliničkih i subkliničkih mastitisa izazvanih navedenim uzročnicima...

Inflammation of the mammary gland, mastitis in cows, are one of the most pressing problems in intensive milk production, causing great economic losses. For many years various approaches to treatment of subclinical and clinical mastitis did not give a satisfactory solution, so the problem of mastitis is still present. Prevent the infiltration of pathogenic agents into the mammary gland, its settlement and growth, impose a constant need for regular inspections of milk, as well as preventive and therapeutic measures to reduce the occurrence of mastitis. Staphylococci can cause an acute, severe, and malignant form of granulomatous mastitis with necrotic changes. Chronic cases of staphylococcal mastitis often go as subclinical forms of diseases of the mammary gland. The most frequent causes of acute catarrhal mastitis (mastitis catarrhalis acuta) are streptococcus (Streptococcus agalactiae, Streptococcus dysgalactiae and Streptococcus uberis), rarely other microorganisms. It occurs immediately after calving, in period of largest milk production. These microorganisms over time lead to the cessation of milk synthesis. Staphylococci and streptococci are very weak antigens, which further complicates finding of effective vaccines. For these reasons an effective commercial vaccine against mastitis caused by S. aureus and Str. agalactiae still not found, but the application of indigenous vaccine in prevention of mastitis may be sufficient. In the literature there are descriptions of inactivated vaccines consist of bacterial particules or entire cells and their toxoid. A new opportunity in making a vaccine against mastitis caused by S. aureus is adding protein A and fibronectin-binding protein as cellular antigens. An entirely new approach to immunization of the mammary gland gave incorporation of S. aureus lysate into biodegradable particles that have a function to stimulate production and opsonisation of antibodies. Given the results of other investigators and our own preliminary studies, and keeping in mind problem that mastitis caused by Staphylococcus aureus and Streptococcus agalactiae represents, goal of the research is the preparation and testing of vaccines whose effectiveness is reflected in the reduction of clinical and subclinical mastitis caused by these pathogens...