ABSTRACT
The aim of this study was to evaluate some physiological parameters as total locomotor activity and subcutaneous temperature in two different bovine breeds under tropical environment. In this study, total locomotor activity and subcutaneous temperature were evaluated in 18 clinically healthy female cows. All cows were divided into 3 groups: group A1 was constituted by 6 Holstein Bos taurus, group A2 was constituted by 6 female Herford Bos taurus cows, and group B was constituted by 6 female Bradford Bos indicus cows. Data recording of total locomotor activity (TLA) and subcutaneous temperature (ST) was performed by means of a subcutaneous thermometer (Thermocron) and an actimeter ACTIWATCH® (Cambridge Neurotechnology Ltd.) based on accelerometer technologies equipped on all subjects to record TLA. At the same time, thermal and hygrometric recording were carried out, considering the subtropical climate of Santa Fe. The application of GLM for statistical analysis showed a significant effect (P < 0.05) on statistical model and time of the day on TLA and ST for all groups; no significative effects on animal parameters were found for ST and TLA except for group B. Circadian parameters have been evaluated according to the single cosinor procedure of ST that showed a diurnal daily rhythmicity for all investigated groups and TLA which is focused almost during the photophase for groups A1 and A2 and during scotophase for group B. Considering different species and breeds, and different environmental conditions, this study suggested that some subjects may be much more able to adapt themselves to environmental stress than others. During their evolution from Bos taurus, zebu cattle (Bos indicus) have acquired genes that confer thermotolerance. Subjects from Bos indicus breeds are better able to regulate body temperature in response to heat stress than Bos taurus subjects.
Subject(s)
Adaptation, Physiological , Locomotion , Cattle , Animals , Female , Temperature , ArgentinaABSTRACT
Abstract Background: Lernaea cyprinacea was introduced in South America with cyprinids. To the best of our knowledge, this ectoparasite has not been reported in Santa Fe province (Argentina). Objective: To report Lernaea cyprinacea presence in Rhamdia quelen under hatchery conditions in Santa Fe province (Argentina). Methods: In May 2014, samples of L. cyprinacea attached to the fins and flanks of R. quelen were obtained in the Chronobiology Laboratory of the Veterinary Sciences School at Esperanza (Santa Fe, Argentina) where they were collected and identified. Results: A description of L. cyprinacea is presented along with detailed records previously reported in this and other regions. Conclusions: Presence of this parasite constitutes evidence of the introduction of exotic species through commercialization of their natural hosts and the potential pathogen colonization of natural environments, which constitutes a threat to the integrity of aquatic ecosystems.
Resumen Antecedentes: la Lernaea cyprinacea fue introducida en América del Sur a través de los ciprínidos, no habiendo siendo previamente registrada en la provincia de Santa Fe (Argentina). Objetivo: reportar la presencia de Lernaea cyprinacea en Rhamdia quelen en condiciones de acuicultivo. Método: en mayo de 2014, se obtuvieron ejemplares de L. cyprinacea, parasitando aletas y flancos de R. quelen en el laboratorio de Cronobiología de la Facultad de Ciencias Veterinarias, en Esperanza (Santa Fe, Argentina), donde fueron colectados e identificados. Resultados: se brinda una descripción de L. cyprinacea y se detallan antecedentes del ectoparasito en ésta y otras regiones. Conclusiones: la presencia de este parásito constituye evidencia de introducción de una especie exótica mediante la comercialización de sus hospedadores naturales y de la potencial colonización por patógenos introducidos en ambientes naturales, lo cual amenaza la integridad de estos ecosistemas.
Resumo Antecedentes: Lernaea cyprinacea foi introduzido na América do Sul através de ciprinídeos, não sendo registrado na província de Santa Fe. Objetivo: relatar a sua presença no Rhamdia quelen, em condições de crescimento. Método: em maio de 2014, foram obtidas individuos de L. cyprinacea, parasitando nadadeiras e flancos em R. quelen, no Cronobiologia Laboratório da Faculdade de Ciências Veterinárias, Esperanza (Santa Fe, Argentina), que foram coletados e identificados. Resultados: uma descrição de L. cyprinacea é relatada, e detalhes prévios da presença deste parasito na região. Conclusões: a presença neste parasito é evidência de introdução de espécies exóticas através da comercialização de seus hospedeiros naturais. O potencial de colonização de patógenos introduzidos em ambientes naturais é uma ameaça à integridade dos ecossistemas.
