Original scientific paper
Pathological findings and molecular diagnostics in cattle serologically positive for bovine leukemia virus in Croatia
Dunja Vlahović
orcid.org/0000-0002-6598-4798
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
*
Branko Šoštarić
Branka Artuković
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Ivan-Conrado Šoštarić-Zuckermann
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Marko Hohšteter
; Bioinstitut d.o.o., Čakovec
Lidija Medven Zagradišnik
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Doroteja Huber
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Dragan Brnić
; Croatian Veterinary Institute, Zagreb, Croatia
Krešimir Severin
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Valerija Benko
orcid.org/0000-0002-3307-9582
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
Lorena Jemeršić
; Croatian Veterinary Institute, Zagreb, Croatia
Andreja Jungić
orcid.org/0000-0002-9497-9904
; Croatian Veterinary Institute, Zagreb, Croatia
Gordan Kompes
; Croatian Veterinary Institute, Zagreb, Croatia
Relja Beck
; Croatian Veterinary Institute, Zagreb, Croatia
Karmen Branović Čakanić
orcid.org/0000-0001-8760-4680
; Croatian Veterinary Institute, Zagreb, Croatia
Krunoslav Sokolić
Andrea Gudan Kurilj
; Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
* Corresponding author.
Abstract
Enzootic bovine leukosis is a chronic viral infectious disease in cattle caused by the bovine leukemia virus (BLV). It has significant economic implications due to losses caused by decreased milk production, increased herd culling rates, reduced lifespan, and increased susceptibility to secondary diseases. The aim of this study was to determine the stage of infection in cows and heifers serologically positive for the BLV virus in the Republic of Croatia, to determine pathological changes in their organs, to detect proviral DNA in the blood, and to determine their susceptibility to secondary bacterial and parasitic infections. From 2015 to
2016, blood samples, 11 organ samples, and feces were collected from 65 serologically positive animals and 10 serologically negative animals (control group). Serological, hematological and molecular examinations were performed of the blood samples. Organ samples were examined grossly and histopathologically. Lung and liver samples were evaluated by bacteriological tests, and feces samples by parasitological tests. Hematological testing showed that the BLV-positive animals were in a state of persistent infection at the
time of slaughter. Gross and histopathological findings showed somewhat more frequent changes in BLV-positive animals compared to the control group. Real-time PCR detected proviral DNA in the blood of 46 out of 65 (70.77%) BLV-positive animals. No increased susceptibility to secondary bacterial or parasitic infections was found in these animals. The statistically significant (p<0.05) higher total of white blood cell count in the blood, the degree of reactive splenic hyperplasia, and the degree of neutrophil infiltration in the splenic marginal zone suggest the potential role of neutrophils as B-helper neutrophils in the spleen, which
is the first such finding described in cattle in Croatia. The borderline significantly higher value of neutrophils in the blood (p=0.051) in BLV-positive animals also supports this finding.
Keywords
enzootic bovine leukosis; pathology; histopathology; real-time PCR
Hrčak ID:
320824
URI
Publication date:
23.9.2024.
Visits: 0 *