Dvogodišnje serološko istraživanje virusa goveđe virusne dijareje, goveđeg alfa-herpesvirusa 1 i virusa goveđe parainfluence tipa 3 na farmama mliječnih krava u Qazvinu, sjeverozapadni Iran

Infections with bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoHV-1), and bovine parainfluenza virus type 3 (BPIV-3) cause diseases in cattle with serious economic consequences worldwide. The objective of the present study was to determine of herd-level and animal-level BVDV, BoHV-1, and BPIV-3 seroprevalence, and evaluate some of the associated risk factors on farms in Qazvin province, Northwestern Iran. A total of 1036 cattle in 16 herds were randomly selected, and their serum samples were tested to detect antibodies to these viruses in a cross-sectional study over 2 years. The results showed the seroprevalence of BVDV, BoHV-1, and BPIV-3 was 100%, 56.3%, and 100% at herd-level and 55.1%, 5.1%, and 95.2% at animal-level, respectively. Statistical analysis revealed that the farm was a strong risk factor for all the studied viruses, while the year was determined as a risk factor for only BVDV (P<0.001). The seroprevalence of BVDV and BPIV-3 was significantly (P<0.01) affected by season. The proportion of seropositive cows increased with age for BVDV and BoHV-1 (P<0.001). Concurrent infection was the highest in mixed infections with BVDV and BPIV-3 (53.2%), and there was a positive correlation between BVDV and BoHV-1 seropositivity (R2= 0.106, P<0.001). The present study shows that infections of BVDV and BPIV-3 are common in cattle in Northwestern Iran and which implies the need to implement control programs to reduce the risk of the spread of these viruses.Infekcije virusom goveđe virusne dijareje (BVDV), goveđeg alfa-herpesvirusa 1(BoHV-1) i virusa goveđe parainfluenze tipa 3 (BPIV-3) uzrokuju pobol u goveda širom svijeta, sa znatnim ekonomskim posljedicama. Cilj ovog istraživanja bio je odrediti seroprevalenciju BVDV-a, BoHV-1 i BPIV-3, na razini stada i na razini životinje, te procijeniti rizične čimbenike povezane s tim virusima na farmama u pokrajini Qazvin u sjeverozapadnom Iranu. U presječnom istraživanju, koje je trajalo više od dvije godine, nasumično je odabrano ukupno 1036 goveda iz 16 stada čiji su uzorci seruma testirani kako bi se pronašla antitijela na tri navedena virusa. Rezultati su pokazali da je seroprevalencija BVDV-a 100 %, BoHV-1 56,3 %, a BPIV-3 100 % na razini stada, dok je na razini životinje seroprevalencija BVDV-a bila 55,1 %, BoHV-1 5,1 %, a BPIV-3 95,2 %. Statistička je analiza pokazala da je farma znatan rizični čimbenik za sve istraživane viruse, dok se kombinacija godine i sezone pokazala rizičnim faktorom samo za BVDV (P < 0,001). Na seroprevalenciju BVDV-a i BPIV-3 znakovito je utjecala sezona (P < 0,01). Omjer seropozitivnih krava za BVDV i BoHV-1 znakovito je rastao s dobi (P < 0,001). Najčešća je koinfekcija bila virusima BVDV i BPIV-3 (53,2 %), a ustanovljena je i pozitivna korelacija između seropozitivnosti BVDV-a i BoHV-1 (R2 = 0,106, P < 0,001). Ovo je istraživanje pokazalo da su infekcije BVDV-om i BPIV-3 česte u goveda u sjeverozapadnom Iranu što upućuje na potrebu uvođenja programa nadzora kako bi se smanjio rizik od širenja ovih virusa