The Infection Status Investigation Of Five Major Diseases In Large-scale Farms In Parts Of Shandong Province

At present, multiple infections or mixed infections of pathogens have become general problems in cattle, and Bovine viral diarrhea-mucosal disease, Infectious Bovine Rhinotracheitis(IBR), Bovine Tuberculosis, Bluetongue(BT) and Bovine Paratuberculosis have become five key infectious diseases which could do great harm to cattle husbandry and impede badly the development of cattle industry in our country. BVDV can be spread via contact of mouth and nose as well as blood. The infected cattle has a high morbidity and low mortality, especially for the cattle that have no clinical symptoms but weakened immunity as a matter of expelling of noxious substance. This can easily lead to other pathogen infection,which can result in the increase of morbidity and mortality and throw great difficulty to disease prevention and control. Infectious Bovine Rhinotracheitis(IBR) is an acute, febrile,and contagious disease(Gibbs and Rweyemammu 1997), which is epidemic worldwide, and it’s caused by Infectious bovine rhinotracheitis virus(IBRV), also named Bovine hepersvirus I(BHV-1). The virus can survive in trigeminal ganglia and ganglion, so it is hard to cure this kind of disease once it attacks an individual. M.TB is a chronic infectious disease caused by Mycobacterium bovis(M. bovis) which found both in human beings and in animals, able to be transmitted to human by dairy products, which seriously threatens the public health and food security and our country, and has defined it as the second class animal epidemic disease.Bluetongue(BT) is a fulminating infectious disease caused by Bluetongue Virus(BTV)belonging to Reoviridae Orbivirus genus and it can spread among ruminants by Culicoides serving as transmission media and now there is no effective therapeutic method for it. Bovine Paratuberculosis is a chronic debilitating infectious disease infected by mycobacterium paratuberculosis and it was mainly found in cattle and sheep. In order to have a better understanding of infection status of these five diseases in different cattle farms, this study has adopted the method of serology, which provides epidemiological data for the control and decontamination of cattle diseases.Serum samples of 741 cattle(inoculated of vaccines of BVDV、IBRV、BTV、M.bovis、MAP) from 25 farms of Shandong Province were detected in this study, using Bovine Viral Diarrhoea Virus Antibody Test Kit(BVDV Ab), Bovine Rhinotracheitis Virus(BHV-1) g E Antibody Test Kit, Bluetongue Virus(BTV) VP7 Antibody Test Kit(Bluetongue Competition),Mycobacterium Bovis Antibody Test Kit and Mycobacterium paratuberculosis Antibody Test Kit(Paratuberculosis Screening) of American idexx company. The result shown that the seroprevalence of BVD is 66.26%(491/741), IBRVg E 31.52%(232/736),M.bovis10.47%(76/726), MAP 4.61%(34/737) and(BTV)VP7 0.41%(7/737). It shows that infection rate of farms is comparatively high and exist mixed infection. The triple infection rate has reached 40%, double infection rate 32%, single infection rate 16%, quadruple infection rate8%, and total detection rate 96%. Different cattle farms have different infection status, and the individual positive rate of BVD in cattle farms is 88.89%, IBR 35%, Mycobacterium Bovis10%, Mycobacterium Paratuberculosis 9.45% and BT 0.28%. The individual positive rate of BVD in beef cattle farms is 34.75%, IBR 41.18%, and Mycobacterium Bovis 5.56%. The results of Mycobacterium Paratuberculosis and BT are all feminine. The individual positive rate of BVD in dairy farms is 50.83%, IBR 20.83%, Mycobacterium Bovis 13.75% and BT27.5%. The results of Mycobacterium Paratuberculosis are feminine.According to the results of the study, it can be seen that there are various kinds of infection status in different areas as well as farms of different scales. When it comes to the infection status of different diseases, there is a great difference in infection rate. The infection rate of BVD is the highest, followed by IBR and Bovine Tuberculosis, and the rate of BT is the lowest. This study has provided epidemiological data for BVD, IBR, Bovine Tuberculosis,Bovine Paratuberculosis and BT, which has important veterinarian lemology and public health significance.