RESUMO
An outbreak of Psoroptes sp.-caused mange was detected in a llama herd of Larcas, Jujuy province, Argentina. Infested llamas showed alopecia, erythema, hyperpigmentation, hyperkeratosis, and inflammation of the ear pinnae, as well as crusts and serous, serosanguineous, or purulent drainage with unpleasant smell in the external ear canal. Microscopic evaluation of skin scrapings revealed 0.5- to 0.7-mm-long acari identified as Psoroptes sp. based on their morphology. Histology showed a typical allergic reaction with perivascular to periadnexal mixed inflammatory infiltrate. Phylogenetic tree analysis showed that the cytochrome c oxidase subunit I gene sequences analyzed from the sampled acari clustered into a single P. ovis clade including sequences isolated from rabbits and bighorn sheep, with P. natalensis as a sister taxon that infested bighorn sheep from the USA. Phylogenetic analysis of cytochrome b sequences showed three well-supported clades, one of which contained the sequences of the Larcas llamas and US bighorn sheep isolates. This is the first report on P. ovis infestation of llamas raised in their original location. Investigations on mange etiological agents acting on South American camelids and their distribution are necessary to implement control strategies to mitigate the negative impacts of these parasitic infections.
Assuntos
Camelídeos Americanos , Infestações por Ácaros , Filogenia , Psoroptidae , Animais , Camelídeos Americanos/parasitologia , Infestações por Ácaros/veterinária , Infestações por Ácaros/parasitologia , Infestações por Ácaros/epidemiologia , Psoroptidae/genética , Psoroptidae/classificação , Argentina/epidemiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Citocromos b/genética , Surtos de Doenças/veterinária , Análise de Sequência de DNARESUMO
This paper aims to describe a case of trombiculosis in llamas from the Puna region of Argentina caused by Eutrombicula cochinocaensis. Trombiculosis is a parasitic infestation caused by the larval form of trombiculid mites, commonly known as chigger mites. Six adult llamas out of eighteen (33%) were infested and showed dermatitis, hyperemia, and crusts together with an orange-dotted pattern. The chigger mites were found mainly in the hind limbs and the abdomen. Microscopic identification of E. cochinocaensis was made by phase-contrast microscopy. Then, a histopathological study of the affected animals' skin was performed. Histological findings included dermatitis withmainly lymphocytic infiltrate, pustules, crusts, hyperkeratosis, and the mites' stylostomes in the dermis and epidermis. This is the first report of trombiculosis caused by E. cochinocaensis in llamas from Argentina. Mites of the family Trombiculidae are vectors of certain diseases to humans and animals and are therefore of sanitary and productive importance.
Assuntos
Camelídeos Americanos , Trombiculíase , Trombiculidae , Animais , Argentina , Camelídeos Americanos/parasitologia , Trombiculíase/veterinária , Trombiculíase/parasitologia , Trombiculíase/patologia , Trombiculidae/classificação , Trombiculidae/fisiologiaRESUMO
Pascalia glauca, a perennial herb known for its toxicity in ruminants, is one of the most important toxic plants in northwestern Argentina. This work describes several outbreaks of natural intoxication with P. glauca from different sources affecting cattle, sheep and goats in different production systems, with morbidity varying between 1% and 100%. Clinical signs included tremors in the hindquarters, recumbency and death. The liver showed swelling, congestion and a mottled appearance. Histopathologic findings included centrilobular hepatocellular necrosis with hemorrhage.
Assuntos
Doenças dos Bovinos , Intoxicação por Plantas , Doenças dos Ovinos , Animais , Argentina/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/patologia , Surtos de Doenças/veterinária , Cabras , Intoxicação por Plantas/epidemiologia , Intoxicação por Plantas/patologia , Intoxicação por Plantas/veterinária , Ruminantes , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/patologiaRESUMO
Hairy vetch (Vicia villosa) poisoning in cattle is characterized by a systemic granulomatous inflammatory response that resembles a type-IV hypersensitivity reaction. Hairy vetch toxicity has been described in cattle worldwide. The aim of this paper was to describe 10 outbreaks of hairy vetch poisoning in cattle studied at INTA EEA Salta and INTA EEA Balcarce, Argentina, from 2004 to 2019. Clinical signs included weakness, pyrexia, dermatitis, alopecia, and progressive weight loss, which leads to death over a clinical course of approximately two weeks. A total of 12 necropsies were performed and tissue samples were collected for histopathology. The main gross changes were observed in skin, lymph nodes, liver, heart, spleen and kidneys. Other tissues, such as pancreas, thyroid, and adrenal glands, were also affected. Histological lesions consisted of multifocal to diffuse granulomatous inflammation in those organs. The toxicity of hairy vetch has been described in several countries of the world. In Argentina, the use of hairy vetch as a cover crop has become common in some regions during the past years. The data suggest that hairy vetch poisoning is an important disease in cattle. More studies are needed to contribute with further information.