RESUMEN
1. The adult possums showed a circadian rhythm of body temperature with a peak in temperature around midnight and a nadir at noon. 2. The young possum within the pouch displayed a circadian rhythm with the highest temperatures during the day and the lowest in the early evening. 3. Although the body temperature of the young possum exceeded that of the mother occassionally, for the major part of the 24 hr the body temperature of the young was lower than that of the mother. 4. The young possum could maintain a steady body temperature between 140 and 167 days post partum. A circadian rhythm of temperature was observed between 157-190 days post partum. 5. All adipose tissue examined with the light and electron microscope had the morphology of white adipose tissue.
Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Zarigüeyas/fisiología , Tejido Adiposo/citología , Tejido Adiposo/ultraestructura , Animales , Ritmo Circadiano , Femenino , Microscopía ElectrónicaRESUMEN
The effect of tick infestations on body weight and various blood parameters was monitored in juvenile northern brown bandicoots (Isoodon macrourus) after release into tick-infested or tick-free enclosures. Three species of ticks were observed in the enclosures, Haemaphysalis humerosa, Ixodes tasmani and Ixodes holocyclus. Bandicoots released into tick-infested enclosures showed a reduced growth rate (1.8 versus 2.5 g/day increase in body weight), a reduced haematocrit value (27.4 versus 40.0%) and an increased number of white blood cells when compared with bandicoots released into tick-free enclosures. These results suggest that tick infestations may influence the health of juvenile I. macrourus.
Asunto(s)
Marsupiales/parasitología , Infestaciones por Garrapatas/veterinaria , Análisis de Varianza , Animales , Peso Corporal , Femenino , Hematócrito/veterinaria , Recuento de Leucocitos/veterinaria , Masculino , Infestaciones por Garrapatas/sangre , Infestaciones por Garrapatas/metabolismo , Garrapatas/clasificación , Garrapatas/crecimiento & desarrolloRESUMEN
The possum is a seasonally breeding marsupial which gives birth in Queensland from March through to September. To ascertain whether this seasonality in breeding is manifest in the male reproductive system, body weight and plasma testosterone concentrations were examined in five possums. Plasma testosterone concentrations fluctuated throughout the year and a seasonal cycle was observed, with a peak in testosterone concentration in March and a nadir in September. Body weights fluctuated in a similar manner. Statistical analysis suggested that the annual plasma testosterone profile correlated well with the rate of change of daylength.
