RESUMO
Managed honeybees play an important role as pollinators. The health and nutritional condition of honeybee colonies (Apis mellifera L.) depends for an important part on management practices, and it is influenced by multiple factors. This study aims to identify the stressors that lead to the loss of honeybee health and its consequences on the colony's productivity. Different aspects related to management practices, productivity, clinical observations related to diseases, presence of sanitary gaps in the apiaries, colony strength, weather and infestation rates by Varroa sp. mites were measured. The information was collected during two monitoring in 53 apiaries in the Province of Santa Fe, Argentina. The results show correlations among many of the management practices, health condition and yield. The most important factors affecting the productivity of the studied honeybee colonies were nuclei preparation, the number of combs in the brood chamber, change of bee queen, disinfection of beekeeping material, among other less significant ones. Although honey production is important in the region, the colony strength was deficient and inadequate during both monitoring. Due to its dependence on management by the beekeeper, it is suggested that a holistic approach could improve bee health, increasing the productivity of honeybees.
RESUMO
The main objective of this study was to determine the impact of Lactobacillus salivarius A3iob, a honey bee gut-associated strain (GenBank code access KX198010), on honey yield. Independent assays were conducted from May to September 2014 and 2015, in three commercial apiaries: Tilquiza, El Carmen and Yala, all located in north-western Argentina. Local Apis mellifera L. bees were kept in standard Langstroth hives; treated hives were fed once a month with 1×105 cfu/ml viable Lactobacillus cells, administered to the bees through a Doolittle-type feeder in 125 g/l sucrose syrup. Control hives were only given the syrup mixed with MRS sterile broth. The main honey harvest was done in December in all groups and we found that there was an overall increase in honey yield from the treated hives. In 2014, all treated hives produced between 2.3 to 6.5 times more honey than the controls. However, in 2015, higher honey average yields in the treated hives at El Carmen and Yala were obtained, yet not at Tilquiza, because of a slight mishap. They experienced the swarming of several bee colonies due to a higher number of bees without appropriate management, which caused the control group to yield more honey compared to the hives fed with Lactobacillus. Interestingly, at El Carmen, two honey harvests were recorded: one in winter and another in summer (July and December 2015, respectively). This unexpected result arose from the particular flora of the region, mainly Tithonia tubaeformis, which blooms in winter. L. salivarius A3iob cells prove to be a natural alternative that will positively impact the beekeepers' economy by providing a higher honey yield.
Assuntos
Abelhas/microbiologia , Suplementos Nutricionais , Mel/normas , Ligilactobacillus salivarius/fisiologia , Probióticos , Ração Animal , Animais , Microbioma Gastrointestinal , Mel/microbiologia , Filogenia , RNA Ribossômico 16S/genéticaRESUMO
Apis mellifera L. is one of the most important natural pollinators of significant crops and flowers around the world. It can be affected by different types of illnesses: american foulbrood, nosemosis, varroasis, viruses, among others. Such infections mainly cause a reduction in honey production and in extreme situations, the death of the colony. Argentina is the world's second largest honey exporter and the third largest honey producer, after China and Turkey. Given both the prominence of the honey bee in nature and the economic importance of apiculture in Argentina and the world, it is crucial to develop efficient and sustainable strategies to control honey bee diseases and to improve bee colony health. Gram-positive bacteria, such as lactic acid bacteria, mainly Lactobacillus, and Bacillus spp. are promising options. In the Northwest of Argentina, several Lactobacillus and Bacillus strains from the honey bee gut and honey were isolated by our research group and characterized by using in vitro tests. Two strains were selected because of their potential probiotic properties: Lactobacillus johnsonii CRL1647 and Bacillus subtilis subsp. subtilis Mori2. Under independent trials with both experimental and commercial hives, it was determined that each strain was able to elicit probiotic effects on bee colonies reared in the northwestern region of Argentina. One result was the increase in egg-laying by the queen which therefore produced an increase in bee number and, consequently, a higher honey yield. Moreover, the beneficial bacteria reduced the incidence of two important bee diseases: nosemosis and varroosis. These results are promising and extend the horizon of probiotic bacteria to the insect world, serving beekeepers worldwide as a natural tool that they can administer as is, or combine with other disease-controlling methods.