Prevalence of bovine herpesvirus-1, bovine viral diarrhea, parainfluenza-3, goat respiratory syncytial, bovine leukemia, and bluetongue viral antibodies in sheep

Sera from healthy sheep were collected in January and March 1982 from flocks of sheep located in southwestern and southeastern Louisiana. These sera were tested for bovine herpesvirus-1 (BHV-1), bovine viral diarrhea virus (BVDV), parainfluenza-3 (PI-3) virus, and goat respiratory syncytial virus (GRSV) antibodies by microtitration virus-neutralization test. The sera were tested also for bovine leukemia virus (BLV) and bluetongue virus (BTV) antibodies by immunodiffusion tests. The number of flocks with seropositive sheep for each virus were: 2/8 (25%) for BVDV; 8/8 (100%) for PI-3 virus; 7/8 (87.5%) for GRSV; and 6/8 (75%) for BTV. Seropositive rates for each virus for the individual sheep tested were: 4/158 (2.5%) for BVDV; 117/158 (74.1%) for PI-3 virus; 77/158 (48.7%) for GRSV; and 21/158 (13.3%) for BTV. All sheep were seronegative for BHV-1 and BLV.     

Prevalence of antibodies to bovine respiratory syncytial virus, bovine viral diarrhea virus, bovine herpesvirus-1, and bovine parainfluenza-3 virus in sheep and goats in Quebec

Serum samples were collected from 1,075 clinically normal sheep and goats from 77 flocks in 7 agricultural regions of Quebec from June to August 1982. Sheep and goats were tested for antibodies to bovine respiratory syncytial virus, bovine viral diarrhea virus, and bovine herpes-virus-1 by the indirect fluorescent antibody technique and for parainfluenza-3 virus by the hemagglutination inhibition test. The prevalence of antibodies in animals to respiratory syncytial virus was 31%; to bovine viral diarrhea virus, 22.2%; to bovine herpesvirus-1, 10.8%; and to parainfluenza-3 virus, 23.2%. Antibodies prevailed in similar proportions in young (less than 1 year) and adult (greater than 1 year) animals.     

Comparative serological response in calves to eight commercial vaccines against infectious bovine rhinotracheitis, parainfluenza-3, bovine respiratory syncytial, and bovine viral diarrhea viruses

A field trial was conducted to compare the serological responses in calves to eight commercial vaccines against infectious bovine rhinotracheitis virus (IBRV), parainfluenza-3 virus (PI3V), bovine respiratory syncytial virus (BRSV), and/or bovine viral diarrhea virus (BVDV). Calves given IBRV, P13V, BRSV, and BVDV vaccines had significantly higher antibodies to these viruses than unvaccinated controls; however, serological responses to killed BVDV vaccines were low. Calves with preexisting antibodies to IBRV, PI3V, BRSV, and the Singer strain of BVDV had lower seroconversion rates following vaccination than calves that were seronegative initially.

Serological responses in calves to IBRV, PI3V, BRSV, and BVDV differed among various commercial vaccines. Antibody titers to IBRV were higher in calves vaccinated with modified-live IBRV vaccines than in those vaccinated with killed IBRV vaccines. Following double vaccination with modified-live IBRV and PI3V vaccines, seroconversion rates and antibody titers to IBRV and PI3V were higher in calves vaccinated intramuscularly than in those vaccinated intranasally. Calves given Cattlemaster 4 had significantly higher titers to BRSV and PI3V, and lower titers to BVDV, than calves given Cattlemaster 3, suggesting that the addition of BRSV to Cattlemaster 4 caused some interaction among antigens.

     

Prevalence of bovine herpesvirus-1, bovine oral diarrhea, parainfluenza-3, bovine adenoviruses-3 and -7, and goat respiratory syncytial viral antibodies in goats

Sera from healthy goats were collected during October 1979 through October 1980. These sera were tested for bovine herpesvirus-1 (BHV-1), bovine viral diarrhea virus (BVDV), parainfluenza-3 (PI-3) virus, bovine adenoviruses (BAV) -3 and -7, and goat respiratory syncytial virus (GRSV) antibodies by microtitration virus-neutralization test. The number of herds with seropositive goats for each virus were: 5/38 (13.2%) for BHV-1; 9/38 (23.7%) for BVDV; 8/38 (21.1%) for PI-3 virus; 1/38 (2.6%) for BAV-3; 15/38 (39.5%) for BAV-7; and 26/34 (76.5%) for GRSV. Seropositive rates for each virus for the individual goats tested were: 6/502 (1.2%) for BHV-1; 9/498 (1.8%) for BVDV; 49/458 (10.75) for PI-3 virus; 1/487 (0.025) for BAV-3; 40/448 (8.9%) for BAV-7; and 166/332 (50.0%) for GRSV.     

Prevalence of antibodies to infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial, and bovine viral diarrhea viruses in cattle in Saskatchewan and Alberta

A total of 1745 healthy cattle from 295 farms in Saskatchewan and Alberta was tested by ELISA for antibodies to four viruses. Antibodies to infectious bovine rhinotracheitis (IBR) virus were found in 37.8% of sera (59.5% of properties), to parainfluenza 3 (PI3) virus in 93.9% of sera (99.7% of properties), to bovine respiratory syncytial (BRS) virus in 78.5% of sera (86.6% of properties), and to bovine viral diarrhea (BVD) virus in 40.6% of sera (66.7% of properties)

The prevalence of PI3 viral antibodies among Saskatchewan cattle was not affected by district of origin, breed, sex, age, or vaccination practices, though BRS viral antibodies appeared less frequent in young, male, and unvaccinated animals. Antibodies to IBR and BVD viruses were less prevalent in the Prince Albert/Tisdale districts and in young, male, and unvaccinated animals, but were more common in Holstein cattle. Antibodies to IBR virus appeared less frequent in Herefords. Antibodies were more prevalent in cattle which had been vaccinated against IBR, BRS, and BVD virus infections.

The relatively small number of cattle sampled from Alberta had a similar prevalence of antibodies to PI3 and BRS viruses to that seen in cattle in Saskatchewan, though IBR and BVD prevalence rates were lower.

     

Presence of antibodies to bovine viral diarrhea-mucosal disease virus (border disease) in sheep and goat flocks in Quebec.

A seroepidemiological study of border disease was conducted in sheep and goats in various areas of Quebec. Sera of 10% of animals of selected flocks were collected and specific antibodies against bovine viral diarrhea- mucosal disease were tested by seroneutralization. Results show that 10.9% and 16% of sheep and goats respectively gave a positive reaction. The lower serological prevalence was found in sheep flocks of the Sherbrooke area (5.4%) while the highest percentage of positive sera was observed in the Quebec area (24.7%). The prevalence in goats varied according to areas (2.6 to 45.5%). No relation was observed in seropositive animals between age, sex, breed and the presence of abortions in the flocks. Our serological results indicate that border disease is probably present in Quebec sheep and goat flocks but that the clinical diagnosis of this disease is not well established.     

Seroepidemiological survey of maedi-visna virus infection in sheep and goat flocks in Quebec.

Maedi-visna, a chronic viral disease of adult sheep characterized by progressive dyspnoea or neurological manifestations, was first recognized and described clinically in Canada in 1970. Seroepidemiological study was conducted in sheep and goats in various areas of Quebec. Sera of 10% of the animals of selected flocks were collected and specific antibodies against maedi-visna virus were tested by a modified direct complement fixation test. Results show seropositive rate of 67.6% for Sherbrooke sheep; of 40.5, 41.1 and 47.1% for Quebec, Saint-Hyacinthe and Nicolet sheep respectively and only 29.2 and 20.0% positive sera in l'Assomption and Rimouski animals. Prevalence rate of positive goats varied according to geographic areas (0 to 36.8%). Statistical analysis of various factors, e.g. age, breed, mode of raising, origin and size of flock showed no relation between these factors and the geographic areas. But, some clinical problems in the sheep flocks such as cough, rapid breathing, mortality and abortion were associated with high infection rate (greater than or equal to 50%) to maedi-visna virus. In goats, no correlation was demonstrated between these clinical signs and serological results. Our results suggest that it is important to consider this disease in an adequate program of preventive medicine in Quebec.     

The association between serological titers in infectious bovine rhinotracheitis virus, bovine virus diarrhea virus, parainfluenza-3 virus, respiratory syncytial virus and treatment for respiratory disease in Ontario feedlot calves.

A seroepidemiological study of the association between antibody titers to infectious bovine rhinotracheitis, parainfluenza-3, bovine virus diarrhea and bovine respiratory syncytial viruses, and treatment for bovine respiratory disease was conducted. A total of 322 calves from five different groups were bled on arrival, then one month later all cases (cattle treated for bovine respiratory disease) were rebled together with an equal number of controls (cattle not treated for any disease). Titers to these viruses varied significantly from group to group. Based on seroconversion, infectious bovine rhinotracheitis virus was active in 4.4%, bovine virus diarrhea virus in 24%, parainfluenza-3 virus in 69.5% and bovine respiratory syncytial virus in 71.3% of the cattle. Cattle with low titers to infectious bovine rhinotracheitis and/or bovine respiratory syncytial viruses on arrival, were at increased risk of subsequent treatment for bovine respiratory disease. Treated cattle also had significantly greater increases to parainfluenza-3 and/or bovine virus diarrhea viruses than control calves. Treatment rates varied considerably from group to group and were not strongly correlated with weight gain in the postarrival period.     

Protection from parainfluenza-3 virus and persistence of infectious bovine rhinotracheitis virus in sheep vaccinated with a modified live IBR-PI-3 vaccine.

Ewes (N = 7) and their lambs (N = 12) were vaccinated with a commercial modified live infectious bovine rhinotracheitis-parainfluenza type 3 virus vaccine. Both the vaccinated ewes and lambs and a group of unvaccinated ewes (N = 8) and their lambs (N = 13) were subsequently challenged with virulent parainfluenza type 3 virus. Although absolute immunity to infection and clinical response was not conferred, the clinical response was less severe in vaccinated lambs. Vaccinated animals also shed parainfluenza type 3 virus in nasal secretions for a shorter time than nonvaccinated animals. Some vaccinated lambs developed a persistent infectious bovine rhinotracheitis virus infection that was recrudesced by treatment with dexamethasone. It was concluded that vaccination was of benefit in reducing the severity of infection with parainfluenza type 3 virus. However, the inclusion of infectious bovine rhinotracheitis virus in a vaccine for sheep respiratory tract disease is highly questionable as it might increase the risk factor associated with vaccination. The consequences of the persistence of infectious bovine rhinotracheitis virus are now known.     

Persistence of antibodies and anamnestic response in calves vaccinated with inactivated infectious bovine rhinotracheitis virus and parainfluenza-3 virus vaccines

Persistence of antibodies in calves vaccinated with 2 types of inactivated infectious bovine rhinotracheitis (IBR) virus and parainfluenza-3 (PI-3) virus vaccines were determined. Calves seronegative for IBR and PI-3 viruses were inoculated with 2 doses of inactivated IBR virus-PI-3 virus vaccines administered 2 weeks apart. Blood samples were obtained from the calves for serum at 2 weeks, 6 months, and 1 year after vaccination. The serums were tested by serum-neutralization tests. Antibody response to the vaccines persisted on a declining scale for 1 year. The anamnestic responses to the vaccines were determined by inoculating the same calves with a booster dose of vaccine 1 year after the original 2 doses were given. Blood samples were obtained from the calves for serum 2 weeks later. The serums were tested by serum-neutralization tests. The single booster dose of vaccine elicited an anamnestic response to both IBR and PI-3 viruses.     

Prevalence of bovine virus diarrhoea and infectious bovine rhinotracheitis antibodies in Nigerian sheep and goats

Neutralising antibodies to bovine virus diarrhoea virus were commoner in Nigerian sheep than goats while precipitating antibodies offered an alternative but less reliable indicator of previous infection. In contrast, neutralising antibodies to infectious bovine rhinotracheitis virus were more common in goats than sheep. These findings are discussed in relation to infectivity rates in cattle and general husbandry practices.     

Bovine viral diarrhea viral infections in feeder calves with respiratory disease: interactions with Pasteurella spp., parainfluenza-3 virus, and bovine respiratory syncytial virus.

The prevalence of bovine viral diarrhea virus (BVDV) infections was determined in a group of stocker calves suffering from acute respiratory disease. The calves were assembled after purchase from Tennessee auctions and transported to western Texas. Of the 120 calves, 105 (87.5%) were treated for respiratory disease. Sixteen calves died during the study (13.3%). The calves received a modified live virus BHV-1 vaccine on day 0 of the study. During the study, approximately 5 wk in duration, sera from the cattle, collected at weekly intervals, were tested for BVDV by cell culture. Sera were also tested for neutralizing antibodies to BVDV types 1 and 2, bovine herpesvirus-1 (BHV-1), parainfluenza-3 virus (PI-3V), and bovine respiratory syncytial virus (BRSV). The lungs from the 16 calves that died during the study were collected and examined by histopathology, and lung homogenates were inoculated onto cell cultures for virus isolation. There were no calves persistently infected with BVDV detected in the study, as no animals were viremic on day 0, nor were any animals viremic at the 2 subsequent serum collections. There were, however, 4 animals with BVDV type 1 noncytopathic (NCP) strains in the sera from subsequent collections. Viruses were isolated from 9 lungs: 7 with PI-3V, 1 with NCP BVDV type 1, and 1 with both BVHV-1 and BVDV. The predominant bacterial species isolated from these lungs was Pasteurella haemolytica serotype 1. There was serologic evidence of infection with BVDV types 1 and 2, PI-3V, and BRSV, as noted by seroconversion (> or = 4-fold rise in antibody titer) in day 0 to day 34 samples collected from the 104 survivors: 40/104 (38.5%) to BVDV type 1; 29/104 (27.9%) to BVDV type 2; 71/104 (68.3%) to PI-3V; and 81/104 (77.9%) to BRSV. In several cases, the BVDV type 2 antibody titers may have been due to crossreacting BVDV type 1 antibodies; however, in 7 calves the BVDV type 2 antibodies were higher, indicating BVDV type 2 infection. At the outset of the study, the 120 calves were at risk (susceptible to viral infections) on day 0 because they were seronegative to the viruses: 98/120 (81.7%), < 1:4 to BVDV type 1; 104/120 (86.7%) < 1:4 to BVDV type 2; 86/120 (71.7%) < 1:4 to PI-3V; 87/120 (72.5%) < 1:4 to BRSV; and 111/120 (92.5%) < 1:10 to BHV-1. The results of this study indicate that BVDV types 1 and 2 are involved in acute respiratory disease of calves with pneumonic pasteurellosis. The BVDV may be detected by virus isolation from sera and/or lung tissues and by serology. The BVDV infections occurred in conjunction with infections by other viruses associated with respiratory disease, namely, PI-3V and BRSV. These other viruses may occur singly or in combination with each other. Also, the study indicates that purchased calves may be highly susceptible, after weaning, to infections by BHV-1, BVDV types 1 and 2, PI-3V, and BRSV early in the marketing channel.     

Susceptibility of cell line cultures of bovine kidney origin to infectious bovine rhinotracheitis and parainfluenza-3 viruses

A comparative study was carried out on the susceptibility of primary bovine embryo kidney (PBEK) cell cultures, and that of AUBEK and MDBK cell lines to infectious bovine rhinotracheitis (IBR) and Parainfluenza-3 (PI-3) viruses.

The cytopathic effects induced by the two viruses were rather inconsistent, based on observations of unstained preparations. On the other hand, there was no significant difference between the susceptibility of the PBEK cultures and the cell line cultures to infection with either virus on the basis of the lesions detected in stained preparations, and of the growth curve patterns.

It is concluded that PBEK cell cultures are more sensitive for isolating IBR or PI-3 viruses than are the AUBEK and MDBK cell lines. However, the latter appear to be satisfactory for studies of these two viruses.     

江苏规模化奶牛场BVD与IBR流行病学调查

为了解江苏地区规模化奶牛场牛传染性鼻气管炎(IBR)及牛病毒性腹泻病(BVD)流行与分布情况,采用商品化酶联免疫吸附试验(ELISA)试剂盒对来自江苏省7个市和不同地区的13个大型规模化奶牛养殖场共540份血清中IBRV抗体进行检测,采用商品化ELISA试剂盒对来自江苏省5个市和不同地区的11个大型规模化奶牛养殖场共460份血清中BVDV抗体进行检测,同时从中随机采集100份血清样本,采用巢式逆转录聚合酶链式反应(nRTPCR)进行BVDV抗原检测与基因分型。结果表明:不同牛场的BHV-Ⅰ抗体阳性率为0%~82.1%%,平均阳性率为21.1%(114/540);不同牛场的BVDV抗体阳性率为0%~98%,平均阳性率为51.5%(237/460);不同牛场的BVDV抗原阳性率为0%~100%,平均阳性率为55%(55/100);对相应样本的BVDV抗原与抗体检测结果进行比较表明,抗原~+/抗体~+牛占40%(40/100),抗原~+/抗体~-牛占15%(15/100),抗原~-/抗体~-牛占35%(35/100),抗原~-/抗体~+牛占10%(10/100);基因分型结果显示,BVDV-Ⅰ型占11%(6/55),BVDV-Ⅱ型为78%(43/55),Ⅰ型与Ⅱ型混合感染占11%(6/55),未发现BVDV-Ⅲ型。研究表明,BVDV和BHV-Ⅰ在江苏省主要规模奶牛场普遍流行,但不同地区、不同牛场的阳性率存在明显差异,大部分牛场均能检测出抗原~+/抗体~-的持续感染牛,BVDV含基因Ⅰ、Ⅱ型,但主要以Ⅱ型感染为主。     

Effects of infection with parainfluenza-3 virus and infectious bovine rhinotracheitis virus on neutrophil functions in calves

Calves were challenge exposed in separate experiments with parainfluenza-3 (PI-3) virus or infectious bovine rhinotracheitis (IBR) virus. Blood neutrophils were assayed for functional activity every other day for at least 3 weeks by random migration, Staphylococcus aureus ingestion, antibody-dependent cell-mediated cytotoxicity, cytochrome-c reduction, iodination, and native chemiluminescence. Exposure to PI-3 virus resulted in a brief febrile response and no other clinical signs. Alterations in total or differential WBC counts were not detected. Chemiluminescence and iodination activities were reduced from activities before exposure. Exposure to IBR virus resulted in mild clinical signs and a febrile response of several days' duration. Total WBC and mononuclear cell counts were reduced. Random migration was reduced, whereas S aureus ingestion was enhanced. We concluded that infection of calves with IBR virus and PI-3 virus might directly or indirectly result in alterations of neutrophil function. The functional alterations apparently are different for each virus. These virus-induced alterations in neutrophil function might predispose calves to secondary bacterial pneumonia.