Nanogel-Mediated antigen delivery: Biocompatibility, immunogenicity, and potential for tailored vaccine design across species.

Nanotechnology has emerged as a promising avenue for enhancing the efficacy of vaccine delivery systems. This study investigates the utilization of nanogels as carriers for the model antigen ovalbumin, with a focus on in vivo assessments in equine and murine models. Nanogels, owing to their biocompatibility and tunable physicochemical properties, offer a versatile platform for efficient antigen encapsulation and controlled release. The encapsulation efficiency and physicochemical characteristics of ovalbumin-loaded nanogels were comprehensively characterized. In vitro biocompatibility was evaluated, finding excellent properties of these nanogels. In vivo evaluations were conducted on both equine and murine subjects, assessing immunogenicity through antibody and splenic cell response. Furthermore, the study propose the potential use of nanogels in tailoring immune responses through the modulation of antigen release kinetics. The results obtained in the in vitro assays showed an increase in the uptake of nanogels by APCs compared to free antigen (OVA). In mice, an absence of inflammatory response in the inoculation site was observed, without systemic damage in the evaluated organs. In addition, non-significant humoral response was found nor cellular proliferation and proinflammatory cytokine production, compared with a traditional adjuvant as aluminum hydroxide, in both animal models. These findings allow further insights into nanogel-based delivery systems and offer valuable insights into their application in various animal models. In conclusion, this research establishes the utility of nanogels as effective carriers for antigens-based vaccines, with interesting biocompatibility properties and highly taken affinity by antigen-presenting cells, without inducing inflammation at the injection site. The study underscores the potential of nanogel technology in revolutionizing vaccine design and highlights the importance of tailored approaches for diverse target species.

Mycoplasma bovis-pneumonia and polyarthritis in feedlot calves in Argentina: First local isolation / Neumonía y poliartritis por Mycoplasma bovis en terneros de feedlot: primeraislamiento local

Abstract Bovine respiratory disease (BRD) is one of the most frequent clinical concerns inweaned calves after their arrival at the feedlot. This work reports the first local isolation ofMycoplasma bovis from feedlot calves with pneumonia and polyarthritis in Argentina. Twentyfour out of 545 calves showed progressive, subacute to chronic respiratory distress, coughing,and fever. Thirty percent of the affected calves also showed lameness and swelling of elbowor carpal, and knee or tarsal joints. Five necropsies were performed and severe multifocal tocoalescent pulmonary nodules, containing white-yellowish caseous exudate encircled by fibroustissue, and fibrinonecrotic arthritis and tenosynovitis were detected. Mycoplasma was isolatedfrom lung and joint samples. The 16S-23S rRNA ITS consensus sequence obtained from theseisolates showed 100% similarity with the same region of M. bovis strains. Since there are no com-mercially available vaccines in the region for the prevention and control of M. bovis pneumoniaand arthritis, surveillance is a priority to reduce the source of disease to naïve animals.

Resumen La enfermedad respiratoria bovina es uno de los problemas sanitarios más fre-cuentes en terneros recién destetados luego de su arribo a los corrales de encierre (feedlots).Este trabajo describe el primer aislamiento local de Mycoplasma bovis de terneros de feedlotcon neumonía y poliartritis en Argentina. Se vieron afectados 24 de 545 terneros; mostraron enfermedad respiratoria progresiva, subaguda a crónica, tos y fiebre. De los terneros afecta-dos, el 30% presentó, además, problemas en articulaciones carpales o tarsales. Se realizaron5 necropsias de terneros afectados y se observaron nódulos pulmonares multifocales a coa-lescentes, que contenían un exudado caseoso blanco-amarillento, rodeados de tejido fibroso,artritis y tenosinovitis fibrinonecrótica. Se aisló Mycoplasma de muestras de pulmón y artic-ulación. La secuencia consenso del gen codificante del ARNr 16S-23S rRNA obtenido de estosaislamientos mostró un 100% de similitud con la misma región de cepas de M. bovis. Teniendoen cuenta que no hay vacunas disponibles comercialmente en la región para la prevencióny el control de neumonías y poliartritis por M. bovis, es importante realizar una vigilanciaepidemiológica a fin de reducir las fuentes de infección para animales susceptibles.

Mycoplasma bovis-pneumonia and polyarthritis in feedlot calves in Argentina: First local isolation.

Bovine respiratory disease (BRD) is one of the most frequent clinical concerns in weaned calves after their arrival at the feedlot. This work reports the first local isolation of Mycoplasma bovis from feedlot calves with pneumonia and polyarthritis in Argentina. Twenty four out of 545 calves showed progressive, subacute to chronic respiratory distress, coughing, and fever. Thirty percent of the affected calves also showed lameness and swelling of elbow or carpal, and knee or tarsal joints. Five necropsies were performed and severe multifocal to coalescent pulmonary nodules, containing white-yellowish caseous exudate encircled by fibrous tissue, and fibrinonecrotic arthritis and tenosynovitis were detected. Mycoplasma was isolated from lung and joint samples. The 16S-23S rRNA ITS consensus sequence obtained from these isolates showed 100% similarity with the same region of M. bovis strains. Since there are no commercially available vaccines in the region for the prevention and control of M. bovis pneumonia and arthritis, surveillance is a priority to reduce the source of disease to naïve animals.

HoBi-like pestivirus in 2 cases of fatal respiratory disease of feedlot cattle in Argentina.

HoBi-like pestivirus (HoBiPeV) is an emerging virus that has been detected in cattle and other ruminants. We diagnosed 2 cases of fatal bovine respiratory disease complex (BRDC) associated with infection with HoBiPeV in a feedlot in Argentina. The main findings in 2 steers autopsied were interstitial bronchopneumonia (case 1) and fibrinous bronchopneumonia (case 2). HoBiPeV was detected by RT-PCR in lungs of both animals and by immunohistochemistry in case 2. Phylogenetic analysis showed that both strains clustered within the "Brazilian-Italian" clade. In case 2, Mannheimia haemolytica was isolated from the lung. There is scant information about the contribution of HoBiPeV to the pathogenesis of BRDC. To our knowledge, HoBiPeV has not been reported previously in association with M. haemolytica pneumonia. Our findings further support the involvement of HoBiPeV in cases of BRDC and contribute to understanding the synergy of this etiologic agent in the pathogenesis of BRD, which is critical for the development of appropriate preventive strategies.

[Outbreak of bovine paralytic rabies in a disease-free region of Argentina]. / Brote de rabia paresiante bovina en la región libre de enfermedad en la Argentina.

We report an outbreak of bovine paralytic rabies in a feed lot in a disease-free area in southern Santa Fe, Argentina. Six of 122 unvaccinated steers died after showing neurological signs (morbimortality = 4.9%) for 24-72 hours, 40-75 days after being transported to the feed lot from a farm located in Formosa. Pathologic examination of the brain in 3 steers revealed gliosis, lymphoplasmacytic meningoencephalitis, and intracytoplasmic inclusion bodies in neurons, along with intralesional detection of the rabies virus antigen by immunohistochemistry in 2 cases. Rabies virus was confirmed by direct immunofluorescence in the brain, and further identified as variant 3a, typical of hematogenous bats, by inoculation in mice followed by indirect immunofluorescence. This represents the first communication of bovine paralytic rabies described in the Pampas plain in Argentina, and evidences that the transport of cattle from endemic to disease-free areas could represent a mechanism of dissemination of this communicable zoonotic disease.

Histophilus somni myocarditis and leptomeningitis in feedlot cattle: case report and occurrence in South America.

We investigated deaths in a group of feedlot steers in Argentina. The main findings in 3 steers autopsied were pulmonary congestion and edema, necrotizing myocarditis, pericarditis, suppurative leptomeningitis, and bronchopneumonia. Histophilus somni was detected by bacterial culture and immunohistochemistry in the hearts of the 3 animals. Partial sequences of the 16S rRNA gene of a H. somni isolate had 99% similarity with other H. somni sequences in GenBank. Most reports of H. somni septicemia in cattle originate from North America and western Europe. There is scant information about cardiac histophilosis in South America. A survey of diagnostic laboratory personnel in 7 South American countries documented various forms of bovine histophilosis in Argentina, Brazil, Uruguay, and Venezuela.

Bovine respiratory syncytial virus seroprevalence and risk factors in feedlot cattle from Córdoba and Santa Fe, Argentina / Seroprevalencia del virus respiratorio sincicial bovino y factores de riesgo asociados en engordes a corral de Córdoba y Santa Fe, Argentina

Bovine respiratory syncytial virus (BRSV) is one of the causative agents of respiratory disease in cattle all over the world, leading to important economic losses. The aim of this work was to determine the seroprevalence of BRSV in feedlot cattle of Argentina and the risk factors associated with the disease. Results showed a high individual seroprevalence of 78.64% (95% confidence interval adjusted -#91;CI-#93; =66.55-90.75%) against the virus. Positive association was found between the presence of high BRSV neutralizing antibody titers, and the following risk factors: cattle age, source of animals, presence of clinical respiratory signs and herd size. This work contributes to updating the understanding of its epidemiology in Argentinean feedlots and poses the need for reevaluating vaccination strategies against this virus in order to control infection and its impact on productivity.

El virus respiratorio sincicial bovino (BRSV) es uno de los agentes causantes de enfermedad respiratoria bovina a nivel mundial, conduciendo a importantes pérdidas económicas. El objetivo de este trabajo fue determinar la seroprevalencia del BRSV en bovinos de engorde a corral de Argentina y estudiar los factores de riesgo asociados. Los resultados mostraron una elevada seroprevalencia individual del 78,64% (IC = 66,55-90,75%) contra el virus. Se encontró una asociación positiva entre la presencia de altos títulos de anticuerpos neutralizantes contra BRSV y los factores de riesgo: edad del ganado, origen de los animales, presencia de signos clínicos respiratorios y el tamaño del rebano. Este trabajo contribuye en gran medida a la comprensión de la epidemiología en los establecimientos de engorde a corral de Argentina y plantea la necesidad de revaluar las estrategias de vacunación contra este virus con el fin de controlar la infección y su impacto en la producción.

Bovine respiratory syncytial virus seroprevalence and risk factors in feedlot cattle from Córdoba and Santa Fe, Argentina.

Bovine respiratory syncytial virus (BRSV) is one of the causative agents of respiratory disease in cattle all over the world, leading to important economic losses. The aim of this work was to determine the seroprevalence of BRSV in feedlot cattle of Argentina and the risk factors associated with the disease. Results showed a high individual seroprevalence of 78.64% (95% confidence interval adjusted [CI]=66.55-90.75%) against the virus. Positive association was found between the presence of high BRSV neutralizing antibody titers, and the following risk factors: cattle age, source of animals, presence of clinical respiratory signs and herd size. This work contributes to updating the understanding of its epidemiology in Argentinean feedlots and poses the need for reevaluating vaccination strategies against this virus in order to control infection and its impact on productivity.

Atypical actinobacillosis in bulls in Argentina: granulomatous dermatitis and lymphadenitis / Actinobacilose atípica em touros na Argentina: dermatite granulomatosa e linfadenite

Actinobacillosis is a common cause of sporadic infection in cattle. It was mostly characterized as a pyogranulomatous inflammation of the tongue, but also soft tissues as lymph nodes, other digestive tract localization and skin. The aim of this study was to describe an episode of granulomatous dermatitis and lymphadenitis affecting a bull herd in Argentina during 2010. Actinobacillus lignieresii was isolated from samples collected from one of the affected bulls, and characteristic lesions were observed. Lesions other than 'wooden tongue' are usually uncommon; however, actinobacillosis should be included as a differential diagnosis for cutaneous diseases.

A actinobacilose é causa comum de infecções esporádicas em bovinos. Esta afeção tem sido caracterizada como uma infecção piogranulomatosa não somente da língua como também de tecidos moles tais como linfonodos, ou outras localizações no trato digestivo e na pele. O objetivo do presente trabalho é descrever um episódio de dermatite piogranulomatosa e linfadenite que afetou um rebanho de touros na Argentina em 2010. As amostras recolhidas de um dos animais afetados permitiram o isolamento de Actinobacillus lignieresii. Observaram-se as lesões características da doença. Habitualmente não são comuns outras lesões para além das descritas como "língua de pau", no entanto, a actinobacilose deve ser incluída como um possível diagnóstico diferencial de doenças cutâneas.

Mortality of a captive axis deer (Axis axis) and a llama (Lama glama) due to ingestion of Wedelia glauca.

The current study describes a naturally occurring cluster of cases of Wedelia glauca intoxication. Seven of 14 axis deer (Axis axis) and 1 of 8 llamas (Lama glama) in a zoo of Buenos Aires province, Argentina, died suddenly after ingestion of a new batch of alfalfa (Medicago sativa) hay bales contaminated with the hepatotoxic plant W. glauca. Necropsies of 1 deer and 1 llama were performed. Pathological findings in both animals included severe diffuse acute centrilobular hepatocellular necrosis and hemorrhage, and clear yellowish translucent gelatinous edema on the wall of the gall bladder and the serosa of the choledochoduodenal junction. Fragments of W. glauca plants were identified in the hay based on the botanical characteristics of the leaves. Samples of gastric contents were examined by microhistological analysis, which identified epidermal fragments of W. glauca based on the presence of characteristic uniseriate glandular hairs (trichomes), confirming recent ingestion of W. glauca in both cases. The fragments were quantified and represented 5% of all examined vegetal fragments in the deer and 10% in the llama.