RESUMEN
Resumen El barbering es una conducta que consiste en halar o recortar el pelo y en algunos casos incluso ingerirlo. Este comportamiento ha sido reportado tanto en el ser humano como en otras especies, no obstante, su presentación en ratones de laboratorio es frecuente en algunos linajes, genera impacto sobre su bienestar y la fiabilidad de los resultados de investigación, siendo un problema destacado en los bioterios de ratones. Al realizar una revisión de literatura disponible sobre esta condición, se identifican múltiples causas, entre estas, deficiencias en el enriquecimiento ambiental, alteraciones de manejo, estrés, conductas aprendidas, ansiedad y dominancia, así como causas genéticas haciendo que algunas cepas, linajes y modelos genéticamente modificados sean más susceptibles al barbering y ayudando a facilitar la comprensión de rutas metabólicas involucradas en esta condición. La etiología múltiple del barbering permite abordar opciones de manejo orientadas hacia la intervención ambiental y algunas estrategias farmacológicas que podrían ser útiles para reducir su incidencia y los problemas de salud y desempeño reproductivo asociados.
Abstract Barbering is a behavior that consists of pulling, cutting, or even ingesting hair. This behavior has been reported in humans or other animals; nevertheless, its presentation in laboratory mice is common in some mice strains, affects these animals' welfare, and results of research studies being a problem in mice facilities. After reviewing the available literature on this condition, multiple causes are identified, including deficiencies in environmental enrichment, management alterations, stress, learned behaviors, anxiety, and dominance, as well as genetic causes, making some strains, lineages, and genetically modified models more susceptible to barbering and helping to facilitate the understanding of metabolic pathways involved in this condition. The multiple etiology of barbering makes it possible to approach management options oriented towards environmental intervention and some pharmacological strategies that could be useful to reduce its incidence and associated reproductive health and performance problems.
Resumo O comportamento de barbeiro consiste em puxar ou aparar o pelo e, em alguns casos, até mesmo ingeri-lo. Esse comportamento tem sido relatado tanto em humanos quanto em outras espécies, entretanto, sua apresentação em camundongos de laboratório é frequente em algumas linhagens, gerando impacto no seu bem-estar e na confiabilidade dos resultados das pesquisas, sendo um problema de destaque nos biotérios. Ao realizar uma revisão da literatura disponível sobre esta condição, múltiplas causas foram identificadas, incluindo deficiências no enriquecimento ambiental, alterações de manejo, estresse, comportamentos aprendidos, ansiedade e dominância, além de causas genéticas, tornando mais suscetíveis à barbearia à algumas linhagens e modelos geneticamente modificados e ajudando a facilitar o entendimento das vias metabólicas envolvidas nessa condição. A múltipla etiologia deste comportamento de barbeiro permite abordar opções de gestão orientadas para a intervenção ambiental e algumas estratégias farmacológicas que podem ser úteis para reduzir a sua incidência e os problemas de saúde e desempenho reprodutivos associados.
RESUMEN
Metronomic chemotherapy is a relevant strategy that uses low doses of antineoplastic drugs for sustained periods to control tumor growth, an alternative frequently utilized in veterinary patients. This work aimed to evaluate the toxic effects of a metronomic oral dose of methotrexate (MTX) for 45 days in tumor-free Wistar rats when compared with control animals. Clinical alterations, body weight, food, and water intake were monitored daily, and bone marrow suppression, hematological, biochemical, and histopathological analyses were performed at three points (days 30, 45, and 60). MTX-treated animals did not demonstrate severe systemic involvement. At 30 days, compared with control animals, MTX-treated animals showed significant leukocytosis (11.9 ± 2.3 vs. 7.8 ± 0.2 106/µL; P < .05) and augmentation of immature myeloid populations from bone marrow (9.0 ± 0.8 vs. 6.5 ± 1.5%; P < .05), and at 60 days, treated animals showed significant neutrophilia (35.0 ± 11.0 vs. 23.00 ± 3.0%; P < .05), depletion of bone marrow lymphocytes (8.2 ± 0.7 vs. 11.5 ± 1.9%; P < .05), and immature myeloid populations (7.2 ± 0.7 vs. 8.3 ± 0.6%; P < .05). At a histopathological level, splenic hypoplasia and respiratory inflammatory lesions were significant when compared with control animals, presenting mild to moderate myelotoxicity, immune suppression, and associated clinical compromise that persisted beyond treatment withdrawal. This suggested that MTX metronomic toxicity should not be neglected owing to the observed residual side-effects and special care should be taken regarding myelosuppression.
