Tremor tales: A cohort study of general and neurological signs in pigs with atypical porcine pestivirus-induced congenital tremor.

Congenital tremor (CT) caused by atypical porcine pestivirus (APPV) is a widespread disease in the swine industry. It is characterized by tremors in newborn piglets, but tremor description and association to other clinical signs are not well documented. This study's objectives were to characterize general and neurological clinical signs of APPV-induced CT and describe the progression and associations between the different signs.

Could Naturally Occurring Coronaviral Diseases in Animals Serve as Models for COVID-19? A Review Focusing on the Bovine Model.

The current pandemic of COVID-19 has highlighted the importance of basic studies on coronaviruses (CoVs) in general, and severe acute respiratory syndrome CoV type 2 (SARS-CoV-2) in particular. CoVs have for long been studied in veterinary medicine, due to their impact on animal health and welfare, production, and economy. Several animal models using coronaviral disease in the natural host have been suggested.

Refined experimental design may increase the value of murine models for estimation of bluetongue virus virulence.

Bluetongue is a serious non-contagious vector-borne viral disease in ruminants, causing poor animal welfare and economic consequences globally. Concern has been raised about the development of novel bluetongue virus (BTV) strains and their possibly altered virulence through the process of viral reassortment. Virulence is traditionally estimated in lethal dose 50 (LD) studies in murine models, but agreement with both and virulence in ruminants is questionable, and a refined experimental design is needed.

Using Biosecurity Measures to Combat Respiratory Disease in Cattle: The Norwegian Control Program for Bovine Respiratory Syncytial Virus and Bovine Coronavirus.

Bovine respiratory disease (BRD) cause important health problems in all cattle husbandry systems. It contributes substantially to the use of antimicrobial substances and compromises animal welfare and the sustainability of the cattle industry. The existing preventive measures of BRD focus at the individual animal or herd level and include vaccination, mass treatment with antimicrobials and improvement of the animal's environment and general health status.

Bovine respiratory syncytial virus in experimentally exposed and rechallenged calves; viral shedding related to clinical signs and the potential for transmission.

Background: Bovine respiratory syncytial virus (BRSV) is an important respiratory pathogen worldwide, detrimentally affecting the economy and animal welfare. To prevent and control BRSV infection, further knowledge on virus shedding and transmission potential in individual animals is required. This study aimed to detect viral RNA and infective virions during BRSV infection to evaluate duration of the transmission period and correlation with clinical signs of disease.

Evaluation of a multiplex immunoassay for bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk against two indirect ELISAs using latent class analysis.

Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCV) are responsible for respiratory disease and diarrhea in cattle worldwide. The Norwegian control program against these infections is based on herd-level diagnosis using a new multiplex immunoassay. The objective of this study was to estimate sensitivity and specificity across different cut-off values for the MVD-Enferplex BCV/BRSV multiplex, by comparing them to a commercially available ELISA, the SVANOVIR BCV-Ab and SVANOVIR BRSV-Ab, respectively.

Temporary carriage of bovine coronavirus and bovine respiratory syncytial virus by fomites and human nasal mucosa after exposure to infected calves.

Background: In order to prevent spread of the endemic pathogens bovine coronavirus (BCoV) and bovine respiratory syncytial virus (BRSV) between herds, knowledge of indirect transmission by personnel and fomites is fundamental. The aims of the study were to determine the duration of viral RNA carriage and the infectivity of viral particles on fomites and human nasal mucosa after exposure to BCoV and BRSV. During two animal infection experiments, swabs were collected from personnel (nasal mucosa) and their clothes, boots and equipment after contact with calves shedding either virus.

Single primer isothermal amplification (SPIA) combined with next generation sequencing provides complete bovine coronavirus genome coverage and higher sequence depth compared to sequence-independent single primer amplification (SISPA).

Coronaviruses are of major importance for both animal and human health. With the emergence of novel coronaviruses such as SARS and MERS, the need for fast genome characterisation is ever so important. Further, in order to understand the influence of quasispecies of these viruses in relation to biology, techniques for deep-sequence and full-length viral genome analysis are needed.

A cohort study of the effect of winter dysentery on herd-level milk production.

Winter dysentery (WD) is a contagious disease caused by bovine coronavirus. It is characterized by acute onset of diarrhea, fever, depression, and reduced milk yield in adult cattle. Although production loss is a well-known consequence of WD, large-scale studies estimating the effect on milk production are lacking.

Genome Sequence of a Bovine Rhinitis B Virus Identified in Cattle in Sweden.

A bovine rhinitis B virus, identified in a calf from Sweden, was genetically characterized. The complete polyprotein was recovered, and phylogenetic analysis showed that this virus has the highest similarity to a bovine rhinitis B virus previously identified in Mexico.

Bovine respiratory syncytial virus and bovine coronavirus antibodies in bulk tank milk - risk factors and spatial analysis.

Bovine respiratory syncytial virus (BRSV) and bovine coronavirus (BCoV) are considered widespread among cattle in Norway and worldwide. This cross-sectional study was conducted based on antibody-ELISA of bulk tank milk (BTM) from 1347 herds in two neighboring counties in western Norway. The study aims were to determine the seroprevalence at herd level, to evaluate risk factors for BRSV and BCoV seropositivity, and to assess how these factors were associated with the spatial distribution of positive herds.

Bovine coronavirus in naturally and experimentally exposed calves; viral shedding and the potential for transmission.

Background: Bovine coronavirus (BCoV) is a widely distributed pathogen, causing disease and economic losses in the cattle industry worldwide. Prevention of virus spread is impeded by a lack of basic knowledge concerning viral shedding and transmission potential in individual animals. The aims of the study were to investigate the duration and quantity of BCoV shedding in feces and nasal secretions related to clinical signs, the presence of virus in blood and tissues and to test the hypothesis that seropositive calves are not infectious to naïve in-contact calves three weeks after BCoV infection.

Bovine respiratory syncytial virus outbreak reduced bulls' weight gain and feed conversion for eight months in a Norwegian beef herd.

Background: Cost-benefit evaluation of measures against respiratory disease in cattle requires accounting with the associated production losses. Investigations of naturally occurring respiratory infections in a herd setting are an opportunity for accurate estimates of the consequences. This article presents estimates based on individual monitoring of weight and concentrate intake of several hundred bulls previous to, during and after a respiratory infection outbreak with bovine respiratory syncytial virus (BRSV) as the main pathogen.

Detection of serum neutralizing antibodies to Simbu sero-group viruses in cattle in Tanzania.

Background: Orthobunyaviruses belonging to the Simbu sero-group occur worldwide, including the newly recognized Schmallenberg virus (SBV) in Europe. These viruses cause congenital malformations and reproductive losses in ruminants. Information on the presence of these viruses in Africa is scarce and the origin of SBV is unknown.

First isolation, identification, phenotypic and genotypic characterization of Brucella abortus biovar 3 from dairy cattle in Tanzania.

Background: Brucellosis is a disease of worldwide public health and economic importance. Successful control is based on knowledge of epidemiology and strains present in an area. In developing countries, most investigations are based on serological assays.

Association between the level of antibodies in bulk tank milk and bovine respiratory syncytial virus exposure in the herd.

Antibody levels in bulk tank milk (BTM) against bovine respiratory syncytial virus (BRSV) are used to classify BRSV status of herds. The aim of this study was to investigate how these levels correspond with the time at which the herds were infected. Bulk tank milk, individual milk and serum samples from cows and young stock were investigated using an indirect ELISA.

Viral replication kinetics and in vitro cytopathogenicity of parental and reassortant strains of bluetongue virus serotype 1, 6 and 8.

Bluetongue virus (BTV), a segmented dsRNA virus, is the causative agent of bluetongue (BT), an economically important viral haemorrhagic disease of ruminants. Bluetongue virus can exchange its genome segments in mammalian or insect cells that have been co-infected with more than one strain of the virus. This process, may potentially give rise to the generation of novel reassortant strains that may differ from parental strains in regards to their phenotypic characteristics.

A review of experimental infections with bluetongue virus in the mammalian host.

Experimental infection studies with bluetongue virus (BTV) in the mammalian host have a history that stretches back to the late 18th century. Studies in a wide range of ruminant and camelid species as well as mice have been instrumental in understanding BTV transmission, bluetongue (BT) pathogenicity/pathogenesis, viral virulence, the induced immune response, as well as reproductive failures associated with BTV infection. These studies have in many cases been complemented by in vitro studies with BTV in different cell types in tissue culture.

Bovine respiratory syncytial virus: infection dynamics within and between herds.

The infection dynamics of bovine respiratory syncytial virus (BRSV) were studied in randomly selected Norwegian dairy herds. A total of 134 herds were tested twice, six months apart. The herds were classified as positive for BRSV if at least one animal between 150 and 365 days old tested positive for antibodies against BRSV, thereby representing herds that had most likely had the virus present during the previous year.

Transplacental infection in goats experimentally infected with a European strain of bluetongue virus serotype 8.

The capability of the recently emerged European strain of bluetongue virus serotype 8 (BTV-8) to cross the ruminant placenta has been established in experimental and field studies in both sheep and cattle. Seroprevalence rates in goats in North-Western Europe were high during the recent outbreak of BTV-8; however the capability of the virus to infect goats through the transplacental route has not been established. In the present study, four Saanen goats were inoculated with the European strain of BTV-8 at 62 days of gestation; this resulted in mild clinical signs, however gross lesions observed post mortem were more severe.

Bluetongue virus genetic and phenotypic diversity: towards identifying the molecular determinants that influence virulence and transmission potential.

Bluetongue virus (BTV) is the prototype member of the Orbivirus genus in the family Reoviridae and is the aetiological agent of the arthropod transmitted disease bluetongue (BT) that affects both ruminant and camelid species. The disease is of significant global importance due to its economic impact and effect on animal welfare. Bluetongue virus, a dsRNA virus, evolves through a process of quasispecies evolution that is driven by genetic drift and shift as well as intragenic recombination.