Paratuberculosis in breeding stock of red Holstein cows

Abstract

This paper describes paratuberculosis in an isolated breeding herd of 25 high-yield dairy cows of the Red Holstein breed. The animals were examined clinically and then given the test for ldelayed type hypersensitivity and their blood serum was examined for the presence of specific antibodies against Mycobacterium avium subsp. paratuberculosis (Map). The clinical examination revealed that two cows exhibited symptoms of the disease that indicated an advanced stage of paratuberculosis. The following parameters were examined in the blood of the cows that showed clinical signs of the disease: leukocytes and erythrocytes count, concentrations of total proteins, albumin, iron, sodium, potassium, and activity of creatine kinase. The analysis of the red blood cell count revealed certain digressions that indicated the existence of hypochromic microcytic anaemia. The number of leukocytes was within the physiological values, but the neutrophil-lymphocyte ratio was disrupted and stood at almost 1:1. The results of the biochemical analyses of the blood serum of diseased cows indicated hypoproteinaemia, hypoalbuminaemia, hypoferremia, hyposodiumaemia, hypokalemia, and increased activities of creatine kinase enzymes. A suspect reaction on the site of application of avian tuberculin was determined in two animals. Animals with clinical signs of the disease reacted negative to the test of delayed type hypersensitivity. The presence of specific antibodies against the cause of paratuberculosis was proven in four animals (16%), including two animals with clinical signs of the disease and one that had a suspect reaction on the site of application of avian tuberculin. Furthermore, one animal that died exhibited macroscopic and microscopic changes regarding the intensity and distribution of lesions, the type of cellular infiltrate, and the number of present acidresistent bacteria, and the changes were characterized as diffuse changes of multibacillary type. The cause of bovine paratuberculosis was isolated from the altered organs.

U ovom radu opisana je paratuberkuloza u izolovanom zapatu od 25 visokomlečnih krava rase crveni holštajn. Životinje u zapatu su klinič ki pregledane, a zatim podvrgnute testu kasne preosetljivosti i ispitivanju krvnog seruma na prisustvo specifičnih antitela protiv Mycobacterium avium subsp. paratuberculosis (Map). Kliničkim pregledom kod dve životinje uočeni su simptomi bolesti koji su ukazivali na uznapredovali stadijum paratuberkuloze. U krvi krava koje su pokazivale kliničke znake bolesti određivani su parametri crvene i bele krvne slike, koncentracija ukupnih proteina, albumina, gvožđa, natrijuma, kalijuma i aktivnost kreatin kinaze. Analizom parametara crvene krvne slike utvrđena su izvesna odstupanja koja su ukazivala na postojanje hipohromne mikrocitne anemije. Broj leukocita je bio u okviru fizioloških vrednosti, ali je neutrofilno-limfocitni količnik bio narušen i iznosio skoro 1:1. Rezultati biohemijskih analiza krvnog seruma obolelih krava ukazali su na hipoproteinemiju, hipoalbuminemiju, hipoferemiju, hiponatremiju, hipokalemiju i povećanu aktivnost enzima kreatin kinaze. Sumnjiva reakcija na mestu aplikacije avijarnog tuberkulina je ustanovljena kod dve životinje. Životinje sa kliničkim znakovima bolesti su bile negativne na test kasne preosetljivosti. Prisustvo specifičnih antitela protiv uzročnika paratuberkuloze dokazano je kod četiri životinje (16%), uključujući dve životinje sa kliničkim znakovima bolesti i jednu koja je imala sumnjivu reakciju na mestu aplikacija avijarnog tuberkulina. Pored toga, kod jedne uginule životinje opisane su makroskopske i mikroskopske promene u odnosu na intenzitet i distribuciju lezija, tip ćelijskog infiltrata i broja prisutnih acidorezistentnih bakterija, a promene su okarakterisane kao difuzne promene multibacilarnog tipa. Iz promenjenih organa izvršena je izolacija uzročnika bovine paratuberkuloze.