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Salmonella enterica is a major food-borne pathogen that affects cattle-rearing systems worldwide. Little information is available on the epidemiology and pathology of salmonellosis and the virulence genes (VGs) carried by Salmonella in spontaneous outbreaks in cattle. We describe epidemiological findings in 15 fatal outbreaks of salmonellosis in Uruguayan dairy farms and the age, clinical signs, and pathology in 20 affected calves. We also describe the serotypes and frequencies of 17 VGs in the causative Salmonella strains and explore their associations with epidemiological, clinical, and pathological findings. Salmonella Typhimurium and Dublin were identified in 11/15 and 4/15 outbreaks, respectively. The most frequent reason for consultation was digestive disease (8 outbreaks caused by S. Typhimurium), followed by sudden death (4 outbreaks, 3 caused by S. Dublin). Morbidity, mortality, and lethality ranged 4.8-100%, 3.8-78.9%, and 10-100%, without significant differences between serotypes. Diarrhea, the most common clinical sign (14 cases), was associated with the Typhimurium serotype (OR = 26.95), especially in ≤ 30-day-old calves with fibrinous enteritis as the main autopsy finding. The Dublin serotype affected ≥ 50-day-old calves and was associated with fibrinosuppurative splenitis (p = 0.01) and tubulointerstitial nephritis (OR = 48.95). The chances of the Dublin serotype increased significantly with age. There was low variability of VG across serotypes. The pefA gene was associated with the Typhimurium serotype (OR = 21.95), macroscopic enteritis (p = 0.03), and microscopic fibrinosuppurative splenitis (p = 0.04). Understanding the epidemiology, pathology, and virulence of S. enterica at the farm level is key to delineating prevention and control strategies to mitigate its impact on animal and human health.

Se realizó un estudio retrospectivo de brotes de babesiosis y anaplasmosis (tristeza parasitaria bovina, TPB) ocurridos entre 2006 y 2016 en el Noroeste argentino (NOA) para evaluar algunos aspectos epidemiológicos y clínicos de estas enfermedades. De 4.398 muestras para diagnóstico, 238 (5,4%) tuvieron sospechas de TPB, las cuales se confirmaron en 106 (44,3%) casos por observación microscópica de los agentes causales. Cuarenta y siete (44,3%) brotes se debieron a Anaplasma marginale, 40 (37,7%) a Babesia bovis y 14 (13,2%) a Babesia bigemina. En cinco (4,7%) focos de babesiosis no se determinó la especie causal de Babesia. Los brotes se diagnosticaron en 62 establecimientos ganaderos de cuatro provincias (Salta, Jujuy, Santiago del Estero y Chaco). La mayoría ocurrieron en verano y otoño, con máxima incidencia en abril y nula en setiembre para ambas noxas. Las vacas adultas fueron la categoría de ganado más afectada. En 58% (61/106) de los brotes murió al menos un bovino, con un número promedio de cuatro muertes por brote. Se concluye que la TPB continúa incidiendo negativamente en la producción bovina del NOA. SUMMARY. Bovine babesiosis and anaplasmosis outbreaks diagnosed at INTA Salta, Argentina: 2006-2016. A retrospective study of babesiosis and anaplasmosis outbreaks (tick fever, TF) was made, which occurred from 2006 to 2016 in Northwest Argentina (NWA), to evaluate clinical and epidemiological aspects of these diseases. From 4,398 specimens, 238 (5.4%) were associated with suspicions of TF and 106 of these cases (44.3%) were confirmed as TF outbreaks by microscopic observation of causal agents. Forty seven (44.3%) were due to Anaplasma marginale, 40 (37.7%) to Babesia bovis and 14 (13.2%) to Babesia bigemina. In five (4.7%) outbreaks of babesiosis, Babesia species were not determined. Outbreaks were diagnosed at 62 different cattle ranches in four provinces (Salta, Jujuy, Santiago del Estero and Chaco). The outbreaks occurred mostly during summer and autumn with a peak of incidence in April and null incidence in September for both diseases. Adult cows were the most affected cattle category. At least one death was recorded in 58% (61/106) of the outbreaks and the average number of deaths was determined as four by outbreak. We conclude that TF maintain its negative historical impact on cattle production of NWA.

Introduction: Hearing loss due to mutations in the DFNB1 locus is characterized by being of pre-consecutive onset, by a degree of severity that varies generally from moderate to profound. Objective- Study deafness related to GJB2 associated with Cochlear.- Analyse results from our population Method: An rretrospective study of patients studied in the Garrahan pediatric hospital with connexin and who received a cochlear implant. Results: Despite the genotype- phenotype correlations observed, there is a significant phenotypic variability that can be the reflection of environmental factors and / or modifying genes that lead to a variable expression. Of the population studied in the Hospital (270 children), 75 patients with two connexin 26 and / or 30 mutations could be identified. Of the total of patients with mutations, 72 has bilateral profound sensorineural hearing loss and only 3 moderate to severe loss. The indicated treatment was a cochlear implant for profound losses and hearing aids for minor hearing losses. In four families, it was possible to act early when detecting in newborns the mutations present in the affected brother and in three families the presence of mutations in newborn siblings was ruled out. In homozygous 35delG patients, a hearing impairment in the first year of life with progression towards severe bilateral profound or profound hearing loss, unlike patients with a homozygous deletion in the GJB6 gene who presented a bilateral deep sensorineural hearing loss from the beginning. We have also observed that all 35delG homozygous patients showed a degree of severe to profound deafness while patients with moderate deafness had at least one non-35delG allele. Conclusion: Deafness related to GJB2 associated with Cochlear Implant is significantly better prognosis compared to the loss of acquired hearing caused by environmental etiologies. However, it was shown that the age of implantation was a better indicator of implant performance than the genotype. [ABSTRACT FROM AUTHOR]

Neospora caninum is a leading cause of bovine abortion worldwide. Although the genetic diversity of this apicomplexan parasite has long been recognized, there is little information on whether infection with different genotypes results in different clinical outcomes or whether infection by a given genotype impairs protective immunity against abortion induced by different genotypes. Here, we provide evidence supporting that natural subclinical infection with isolate NcUru3 of N. caninum in a pregnant heifer did not provide protection against abortion caused by a different N. caninum genotype in the subsequent gestation. A Holstein heifer delivered a healthy calf congenitally infected with N. caninum . Specific anti- N. caninum IgG was detected by indirect ELISA in sera obtained from the dam at calving and the calf before ingestion of colostrum, indicating in utero exposure to the parasite in the latter. A N. caninum strain named NcUru3 was isolated and characterized by multilocus microsatellite typing from the brain of this neonate euthanized at 9 days of age. Sixty days after calving, the cow got pregnant, although she aborted spontaneously at ~6 months of gestation. Pathologic examination of the aborted fetus and placenta revealed typical lesions of neosporosis, including encephalitis, myocarditis, hepatitis, myositis, and placentitis. Neospora caninum DNA was amplified from the fetal brain, heart, kidney, and placenta, and multilocus microsatellite typing revealed a genotype that differed from isolate NcUru3 at the level of microsatellite marker 6A (MS6A). Serum obtained from the dam at the time of abortion had IgG that cross-recognized isolate NcUru3, as demonstrated by immunoblotting, indicating that the humoral immune response did not prevent the other genotype from infecting the fetus and inducing fetoplacental lesions and abortion. This is the first description of one same dam transmitting two N. caninum genotypes to her offspring in subsequent gestations., (Copyright © 2022 Giannitti, Aráoz, da Silva Silveira, Francia, Robello and Cabrera.)

The aim of this work was to identify causes of abortion through laboratory investigations in sheep flocks in Uruguay. One hundred cases of abortion, comprising 58 fetuses, 36 fetuses with their placentas, and 6 placentas were investigated in 2015-2021. Cases were subjected to gross and microscopic pathologic examinations, and microbiological and serological testing for the identification of causes of abortion, including protozoal, bacterial, and viral pathogens. An etiologic diagnosis was determined in 46 (46%) cases, including 33 (33%) cases caused by infectious pathogens, as determined by the detection of a pathogen along with the identification of fetoplacental lesions attributable to the detected pathogen. Twenty-seven cases (27%) were caused by Toxoplasma gondii , 5 (5%) by Campylobacter fetus subspecies fetus , and 1 (1%) by an unidentified species of Campylobacter . Fourteen cases (14%) had inflammatory and/or necrotizing fetoplacental lesions compatible with an infectious etiology. Although the cause for these lesions was not clearly identified, T. gondii was detected in 4 of these cases, opportunistic bacteria ( Bacillus licheniformis, Streptococcus sp.) were isolated in 2 cases, and bovine viral diarrhea virus 1 subtype i (BVDV-1i) was detected in another. Campylobacter jejuni was identified in 1 (1%) severely autolyzed, mummified fetus. BVDV-2b was identified incidentally in one fetus with an etiologic diagnosis of toxoplasmosis. Microscopic agglutination test revealed antibodies against ≥1 Leptospira serovars in 15/63 (23.8%) fetuses; however, Leptospira was not identified by a combination of qPCR, culture, fluorescent antibody testing nor immunohistochemistry. Neospora caninum, Chlamydia abortus, Chlamydia pecorum, Coxiella burnetii and border disease virus were not detected in any of the analyzed cases. Death was attributed to dystocia in 13 (13%) fetuses delivered by 8 sheep, mostly from one highly prolific flock. Congenital malformations including inferior prognathism, a focal hepatic cyst, and enterohepatic agenesis were identified in one fetus each, the latter being the only one considered incompatible with postnatal life. Toxoplasmosis, campylobacteriosis and dystocia were the main identified causes of fetal losses. Despite the relatively low overall success rate in establishing an etiologic diagnosis, a systematic laboratory workup in cases of abortion is of value to identify their causes and enables zoonotic pathogens surveillance., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The handling editor GC declared past co-authorships with the authors MD, CS, RC, VA, JA, and FGi., (Copyright © 2022 Dorsch, Francia, Tana, González, Cabrera, Calleros, Sanguinetti, Barcellos, Zarantonelli, Ciuffo, Maya, Castells, Mirazo, da Silva Silveira, Rabaza, Caffarena, Doncel Díaz, Aráoz, Matto, Armendano, Salada, Fraga, Fierro and Giannitti.)

Campylobacter fetusfetus (Cff) is a major infectious cause of abortion in sheep worldwide, and an opportunistic human pathogen. Information on Cff as an ovine abortifacient in South America is limited. We describe a case of abortion caused by a multidrug resistant strain of Cff in a sheep in Uruguay. In August 2017, 3/57 pregnant ewes (5.3%) aborted whithin one week. Histopathologic examination of the placenta of an aborted ewe revealed severe neutrophilic and fibrinonecrotizing placentitis with vasculitis and thrombosis of the chorionic arterioles. Cff was isolated on microaerobic culture in Skirrow agar, and further confirmed by 16S rDNA PCR amplification and sequencing, and endpoint and real time PCR assays. Antimicrobial sensitivity testing revealed resistance to tetracyclines, nalidixic acid, telithromycin and clindamycin. Other abortifacients were not detected. Further studies are necessary to determine the geographic distribution, ecology, epidemiology, economic impact, and antimicrobial resistance of Cff in sheep flocks in Uruguay., (Copyright © 2021 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.)

Baccharis coridifolia is one of the most common poisonous plants affecting livestock in Uruguay. Poisoning occurs when animals raised in areas free of B. coridifolia are transported to pastures containing the plant. Young stock become spontaneously averted to it after ingesting non-toxic amounts of the plant. As B. coridifolia is widespread in the country, farmers selling livestock report when animals have been raised in areas with the plant, meaning that they are naturally averted and will not ingest it if introduced in B. coridifolia-containing paddocks. Of 2456 farmers from 18 departments of Uruguay selling cattle through online auctions between June 2019 and May 2020, 78% mentioned that the animals they were selling were raised in grasslands containing B. coridifolia. However, only 35.8% of the farmers from three departments of Eastern Uruguay mentioned that their cattle were raised in grasslands with B. coridifolia. Herds from these departments presented 16.7 times (95% CI: 13.1-21.3; p < 0.001) more risk of not being naturally averted to B. coridifolia ingestion than the herds of the other 15 departments of the country. In this paper we review all outbreaks of B. coridifolia poisoning reported in livestock in Uruguay from 1911 to present. We also describe three outbreaks of poisoning, one in cattle and two in sheep that were poisoned in the same farms in which the animals were raised. Intoxication occurred when the animals raised indoors and/or in cultivated pastures without B. coridifolia were introduced into grasslands of the same farms containing B. coridifolia. Typical gastrointestinal lesions were observed in pathological examinations. Furthermore, two of three necropsied heifers showed severe acute nephrosis, which had not been reported previously in this poisoning., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Campylobacter fetus is an important reproductive pathogen of ruminants that occasionally infects humans. Here, we describe the complete circularized genome of a strain of Campylobacter fetus subsp. fetus isolated from a sheep. The final assembly consisted of a unique contig with a length of 1,849,237 bp., (Copyright © 2020 Costa et al.)

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.

Rhipicephalus microplus causes high economic losses for Uruguay; the country is divided into a R. microplus-free area and an endemic area. The aim of this research was to evaluate the R. microplus and tick fever situation in Uruguay and the feasibility of implementing R. microplus control or elimination programs to reduce the number of infested farms. A representative survey was performed to determine the number of infested farms, the number of farms with outbreaks of tick fever and the control and preventive measures being used. Control or elimination programs using generational treatment were implemented on 30 farms. Previously, a situation diagnosis was performed by evaluating the background of each farm, identifying acaricide resistance, serologically evaluating the enzootic stability of tick fever, and analyzing the risk of R. microplus introduction to farms. According to the survey, R. microplus was present on 9544 (36%) farms, and 3436 (36%) of these farms experienced outbreaks of tick fever. Only 323 (9.4%) farmers used the tick fever vaccine. Of the 30 farms for which control or elimination programs were carried out, 18 reduced the number of treatments applied per year and six achieved the elimination of the cattle tick. It is concluded that by administering elimination or control programs, it is possible to reduce the number of infested farms and the number of treatments to maintain control. New surveys should be performed to measure the degree of technology adoption by farmers and to analyze the advances in tick control or elimination programs on farms.

Sarcocystis spp. are causative agents of bovine eosinophilic myositis and/or myocarditis, which are chronic subclinical myopathies that are occasionally responsible for condemnation at slaughterhouses. Sarcocystis cruzi is a protozoan parasite of worldwide distribution transmitted by canids, most commonly associated with subclinical infection in cattle. Although S. cruzi infections can rarely lead to fatal systemic disease, fatal cardiac cases with confirmation of the etiologic diagnosis have not been reported, to our knowledge. We describe herein an unusual case of S. cruzi -induced fatal bovine eosinophilic myocarditis. A 22-mo-old, Holstein-Hereford heifer, in a group of 110 cattle on pasture, manifested growth retardation and died in February 2017. Autopsy revealed myriad yellow-green 1-3-mm coalescing foci, surrounded by fibrosis, affecting ~75% of the ventricular myocardium. Pulmonary edema, ascites, and hydrothorax were consistent with chronic congestive heart failure. Histology revealed severe eosinophilic, granulomatous, necrotizing myocarditis, with multinucleate giant cells, fibrosis, and mineralization. Numerous thin-walled protozoan cysts resembling Sarcocystis spp. were present in the necrotic foci and within the sarcoplasm of adjacent cardiomyocytes. PCR and sequencing of the 18S rRNA gene revealed 99.9-100% homology with S. cruzi . Sarcocystosis can be a rare cause of fatal myocarditis in cattle.

Acute leptospirosis is an infrequent disease in sheep that can cause jaundice, haemolysis, haemoglobinuria, hepatitis and nephritis. In most reports the diagnoses have been made by clinical, pathological or serological evidence without isolation or direct identification of the agent. Here, we report one confirmed and one presumptive outbreak of acute leptospirosis in suckling lambs from two unrelated sheep farms in Uruguay with mortalities of 9/60 (15%) and 9/163 (5.5%) lambs. Both outbreaks occurred in Sep-Oct 2017 after heavy rainfall and flooding events. The main gross and histologic pathological findings in two autopsied lambs, one from each farm, included severe diffuse jaundice, haemoglobinuria, acute necrotizing hepatitis with cholestasis and interstitial nephritis. Leptospira interrogans serogroup Pomona serovar Kennewicki was isolated from sheep in both flocks and the same genotype was identified directly in clinical samples from infected animals, including one of the deceased lambs subjected to autopsy, by amplification and partial sequencing of rrs and secY genes. This serovar has recently been identified in infected cattle and humans in Uruguay. The impact of Leptospira spp. infection in ovine health, and the epidemiologic role of sheep as reservoirs of leptospirosis for humans and animals need further investigation., (© 2019 Blackwell Verlag GmbH.)