Calidad nutricional del polen y efecto de la alimentación complementaria sobre poblaciones de abeja "Apis mellifera iberiensis"

Abstract

Climate change is affecting all ecosystems on the planet. Some evidence of this change is high temperatures, frequent and prolonged droughts, irregular rainfall, etc. In various ways, these factors affect species, such as plants and pollinating insects. The domestic bee is one of the most economically and ecologically critical pollinating insects that is being directly and indirectly affected by the factors that cause climate change. Bees depend on the nectar and pollen produced by plants. Therefore, when plants are affected by climatic factors, bees suffer nutritional stress. Since bees depend on the pollen they consume, it is necessary to analyze its nutritional content to identify nutrient deficiencies. Rapeseed (Brassica napus) and apple (Malus domestica) are two of the monocultures that the domestic bee (Apis mellifera) pollinates and from which they obtain nectar and pollen. Furthermore, the variation of pollen nutrients can influence the productive and reproductive behavior of the hive. Moreover, microsporidia such as Nosema sp and parasites such as the Varroa sp mite contribute to reducing the lifespan of bees and adequate development of larvae. Finally, in the last decade, it has been shown that there is a close and positive relationship between the components of the immune system of insects and the existence of a specific intestinal flora of microorganisms, the microbiota. Thus, the main objectives of this thesis were: 1) to evaluate the nutrient content of monocultures B. napus and M. domestica located in Albacete and Murcia (Spain), respectively; 2) to evaluate the nutrient content of pollen in the Murcia University (Spain), apiary during a beekeeping cycle; 3) to evaluate the effect of different diets with different levels of protein on physiological parameters of newborn bees, and 4) evaluate the effect of different diets to which bacterial strains have been added to act as probiotics in apiaries located in Murcia and Soria (Spain). Cultures B. napus and M. domestica were found to produce pollen deficient in fat and protein. Of the amino acids analyzed, it was observed that Trp and Met are found in amounts lower than those required by bees, while Mn, Cu, and Zn were the most deficient minerals. During an annual cycle, all the parameters evaluated increased during the spring, decreased during the summer, and increased again during the autumn. The amount of pollen and the percentage of protein positively influence the number of operculated larvae. The environmental temperature influences the amount of pollen collected, while the precipitation influences the percentage of humidity. Finally, food consumption increased as the age of the bees and body weight increased. Protein levels do not affect body fat content, but age suggests that bees may adjust their fat levels as they age. The insect's age is closely related to phenoloxidase activity, especially at six and nine days of age. In addition, these parameters are related to protein levels, especially when fed with diets with 9% and 12% protein content. The number of Nosema sp spores was higher in Murcia (Spain) hives supplemented with diets 2 and 4, both under patent restrictions. However, the infestation decreased with time