Diseases associated with bovine viral diarrhea virus subtypes 1a and 2b in beef and dairy cattle in Uruguay.

Bovine viral diarrhea virus (BVDV, Pestivirus) causes significant economic losses to the livestock industry worldwide. Although serological surveys show that BVDV exposure is widespread in cattle in Uruguay, BVDV-associated diseases are greatly underreported. The aim of this work is to describe the epidemiological, clinical, pathological, and virological findings from spontaneous outbreaks of BVDV-associated diseases in cattle in Uruguay. Diagnostic investigations were performed during 6 spontaneous disease outbreaks on beef and dairy cattle farms in the departments of Colonia, Rio Negro, and Soriano between November 2016 and April 2018. Carcasses of 8 naturally deceased cattle from these outbreaks were necropsied and subjected to histological examination and immunohistochemistry to detect BVDV antigen in the tissues. Reverse transcription real-time PCR and genomic sequencing were also performed to identify BVDV at the species and subtype levels. Other ancillary diagnostic tests, including bacterial cultures, were performed on a case-by-case basis to rule in/out differential diagnoses based on initial clinicopathological presumptive diagnoses. BVDV-associated conditions that were diagnosed in the 8 cases included mucosal disease, transient postnatal BVDV infections associated with digestive/septicemic salmonellosis by Salmonella serovar typhimurium, Histophilus somni bronchopneumonia, urinary tract coinfections with Escherichia coli and Streptococcus sp., enteric coinfection with coccidia, and transplacental fetal infections and abortions with Neospora caninum coinfection. BVDV-1a and BVDV-2b were each identified in four of the eight cases. We conclude that BVDV-1a and BVDV-2b contribute significantly to disease and mortality in cattle in Uruguay. Future research should estimate the economic impact of BVDV in the Uruguayan livestock sector.

Evaluation of losses in carcasses of cattle naturally infected with Fasciola hepatica: effects on weight by age range and on carcass quality parameters.

Although fasciolosis is a relatively common disease, the productive and economic losses resulting from cattle with chronic fasciolosis are unclear. This paper aims to investigate the effect of fasciolosis on the parameters of carcass quality and discuss the hypothesis that the effects on weight differ among age ranges of cattle. For this, we analysed abattoir data of 30,151 bovines, from 928 farms, slaughtered in Uruguay in 2016, of which 33.9% (95% confidence interval (CI): 27.3-41.1%) had Fasciola hepatica (liver fluke). A mixed model was built to assess whether the effect of fasciolosis on weight differs depending on the age range, using the interaction term 'age*F. hepatica'. The effect on the carcass parameters was tested using a proportional logistic regression. The interaction of age and F. hepatica was statistically significant (P < 0.001). Differences in carcass weights between infected and non-infected animals were observed mostly at younger ages (up to 30 months), with the highest difference observed in the 23-30 months age range (estimated marginal mean difference of 6.34 kg). Overall, the presence of F. hepatica was positively associated with poor conformations and lower fat scores of carcasses (P < 0.001). The carcasses of cattle infected with F. hepatica had 0.16 times greater odds of having worse conformation scores than carcasses of cattle without F. hepatica (proportional odds ratio (POR) = 1.16; 95% CI: 1.07-1.26). Similarly, carcasses of cattle with F. hepatica had 0.30 times (POR = 1.30, 95% CI: 1.23-1.39) greater odds of having poorer fat scores than carcasses of cattle without F. hepatica. Therefore, infection with F. hepatica is associated with poorer carcass quality parameters and lower weights, and the effect on weight differs across age ranges.

Outbreak of contagious ecthyma caused by Orf virus (Parapoxvirus ovis) in a vaccinated sheep flock in Uruguay.

Orf virus (ORFV) causes contagious ecthyma (CE), a highly transmissible, zoonotic disease of small ruminants. CE most commonly affects lambs and unvaccinated sheep. This work reports epidemiologic, clinicopathologic, and virologic findings in a CE outbreak in a vaccinated sheep flock in Uruguay and failure to detect ORFV in a commercial vaccine.