Tesis Doctorado
The physiological and life-history costs of parasitism: effect of the interaction between temperature and the ectoparasite Varroa destructor on Apis mellifera
Autor
Aldea Sánchez, Patricia Loreto
Institución
Resumen
European bees (Apis mellifera) are very important for human activity, but since 2006 there have been high losses of productive colonies. Varroa destructor is considered one of the main culprits, added to other factors such as malnutrition, pesticides and climate change. The objective of this thesis was to determine the interrelationship between temperature and the ectoparasite Varroa destructor in the physiological performance of Apis mellifera, evaluating energy expenditure, maximum thermal tolerance (CTMax), survival, protein and hemolymphatic cell count. For this purpose, we worked with bees acclimatized to two temperatures (TAcc 32 and 38 °C) and different parasitic load (0, 1 or 2 varroas). It was obtained that the higher TAcc reduced the energy expenditure, survival, proteins and total cells, but their values are negatively affected when the number of mites increases. On the other hand, survival time against high temperatures is significantly higher in the group with TAcc 38 °C, being reduced with the number of mites and with the interaction of both factors. CTMax values were similar between treatments, showing that exposure temperature is a more determinant variable than TAcc or parasitic load. Key words: Thermal tolerance, survival, fitness.