First large-scale study reveals important losses of managed honey bee and stingless bee colonies in Latin America.

Over the last quarter century, increasing honey bee colony losses motivated standardized large-scale surveys of managed honey bees (Apis mellifera), particularly in Europe and the United States. Here we present the first large-scale standardized survey of colony losses of managed honey bees and stingless bees across Latin America. Overall, 1736 beekeepers and 165 meliponiculturists participated in the 2-year survey (2016-2017 and 2017-2018). On average, 30.4% of honey bee colonies and 39.6% of stingless bee colonies were lost per year across the region. Summer losses were higher than winter losses in stingless bees (30.9% and 22.2%, respectively) but not in honey bees (18.8% and 20.6%, respectively). Colony loss increased with operation size during the summer in both honey bees and stingless bees and decreased with operation size during the winter in stingless bees. Furthermore, losses differed significantly between countries and across years for both beekeepers and meliponiculturists. Overall, winter losses of honey bee colonies in Latin America (20.6%) position this region between Europe (12.5%) and the United States (40.4%). These results highlight the magnitude of bee colony losses occurring in the region and suggest difficulties in maintaining overall colony health and economic survival for beekeepers and meliponiculturists.

[Characterization of a microbial community isolated from honey bee colonies]. / Caracterización de una comunidad microbiana aislada de colonias de abejas melíferas.

The microbial communities within honey bee colonies contribute to the defense against pathogens. The goal of this study was to isolate, identify, and lyophilize lactic acid bacteria and bifidobacteria from the gut of nurse bees and bee bread in Apis mellifera colonies. Bacterial cultures from the intestinal content were conducted, and subsequently identified, sequenced, and lyophilized. Cross-antagonism among them was also assessed. Studies based on 16 S rRNA gene Sanger sequencing revealed that the MC3 strain had 100% identity with Bifidobacterium choladohabitans, the PP2B strain showed 99.16% similarity with Enterococcus faecium, while the PP1 strain exhibited 99.49% similarity with Lacticaseibacillus sp. and the PP1B strain showed 99.32% similarity with Lacticaseibacillus sp. There was no evidence of cross-antagonism among the strains, and the lyophilization process showed good stability and conservation. This is the first report of the isolation of B. choladohabitans from honey bee gut in Argentina, and also associates the presence of E. faecium with bee bread.

Development of a loop-mediated isothermal amplification (LAMP) and a direct LAMP for the specific detection of Nosema ceranae, a parasite of honey bees.

Nosema ceranae is a ubiquitous microsporidian pathogen infecting the midgut of honey bees. The infection causes bee nosemosis, a disease associated with malnutrition, dysentery, and lethargic behavior, and results in considerable economic losses in apiculture. The use of a rapid, sensitive, and inexpensive DNA-based molecular detection method assists in the surveillance and eventual control of this pathogen. To this end, a loop-mediated isothermal amplification (LAMP) assay targeting the single-copy gene encoding the polar tube protein 3 (PTP3) has been developed. Genomic DNA of N. ceranae-infected forager bees sampled from distant geographic regions could be reliably amplified using the established LAMP assay. The N. ceranae-LAMP showed higher sensitivity than a classical reference PCR (98.6 vs 95.7%), when both approaches were applied to the detection of N. ceranae. LAMP detected a ten-fold lower infection rate than the reference PCR (1 pg vs 10 pg genomic DNA, respectively). In addition, we show highly specific and sensitive detection of N. ceranae from spore preparations in a direct LAMP format. No cross-reactions with genomic DNA and/or spores from N. apis, often co-infecting A. mellifera, or from N. bombi, infecting bumble bees, were observed. This low-cost and time-saving molecular detection method can be easily applied in simple laboratory settings, facilitating a rapid detection of N. ceranae in honey bees in epidemiological studies, surveillance and control, as well as evaluation of therapeutic measures against nosemosis.

Weissella paramesenteroides encapsulation and its application in the use of fish waste.

The goal of the present study was to evaluate the encapsulation of Weissella paramesenteroides, isolated from bee bread, as a technological tool for its use in biological fish silage. The pH decrease in fish silages using the bacteria encapsulated and in a non-encapsulated form was compared. W. paramesenteroides showed a good performance in the development of biological fish silage. The alginate encapsulation method showed an encapsulation efficacy of 85% and provides a reliable technological application.

Encapsulación de Weissella paramesenteroides y su aplicación en residuos de pescado / Weissella paramesenteroides encapsulation and its application in the use of fish wastes

The goal of the present study was to evaluate the encapsulation of Weissella paramesenteroides, isolated from bee bread, as a technological tool for its use in biological fish silage. The pH decrease in fish silages using the bacteria encapsulated and in a non-encapsulated form was compared. W. paramesenteroides showed a good performance in the development of bioEnc ap su lati on; logical fish silage. The alginate encapsulation method showed an encapsulation efficacy of 85% and provides a reliable technological application.

El objetivo del presente estudio fue evaluar la encapsulación de Weissella paramesenteroides, aislada a partir del pan de polen, como herramienta tecnológica para su uso en la elaboración de ensilado biológico de pescado. Se comparó el descenso de pH para los ensilados utilizando la bacteria encapsulada y no encapsulada. W. paramesenteroides mostró un buen desempeño en el desarrollo de ensilado biológico de pescado. El método de encapsulación con alginato mostró una eficacia del 85% y puede ser utilizado para su aplicación tecnológica.

Detection of Lotmaria passim in Africanized and European honey bees from Uruguay, Argentina and Chile.

Trypanosomatids affecting honey bees, Crithidia mellificae and Lotmaria passim, have been poorly studied in South America. We therefore analyzed their presence in Africanized and European honeybees from Uruguay, Argentina and Chile collected between 1990 and 2011 and assessed their association with other bee parasites and pathogens. Crithidia mellificae was not detected while L. passim was wide-spread. This report shows that L. passim has been present in this region at least since 2007 and it infects both Africanized and European honey bees. L. passim infected colonies showed high V. destructor parasitization levels, suggesting an association between them.

Bee bread increases honeybee haemolymph protein and promote better survival despite of causing higher Nosema ceranae abundance in honeybees.

Adequate protein nutrition supports healthy honeybees and reduces the susceptibility to disease. However little is known concerning the effect of the diet on Nosema ceranae development, an obligate intracellular parasite that disturbs the protein metabolism of honeybees (Apis mellifera). Here we tested the effect of natural (bee bread) and non-natural protein diets (substitute) on haemolymph proteins titers of honeybee and N. ceranae spore production. The natural diet induced higher levels of protein and parasite development, but the survival of bees was also higher than with non-natural diets. The data showed that the administration of an artificially high nutritious diet in terms of crude protein content is not sufficient to promote healthy bees; rather the protein ingested should be efficiently assimilated. The overall results support the idea that the physiological condition of the bees is linked to protein levels in the haemolymph, which affects the tolerance to parasite; consequently the negative impact of the parasite on host fitness is not associated only with the level of infection.

Efficacy of formic acid in gel for Varroa control in Apis mellifera L.: importance of the dispenser position inside the hive.

The efficacy of formic acid in a gel matrix was evaluated in two groups of honeybee colonies. In Group 1, a dispenser with 120 g of formic acid (70%) in gel was placed on the brood combs and another dispenser with the same dose was located on the hive bottom (total dose, 240 g). Group 2 received two doses of 240 g of formic acid (70%) in gel and each application was applied in two dispensers containing 120 g of the formic acid solution each and they were located over the brood chamber (total dose, 480 g). In Group 2, the period between both applications was 15 days, and the efficacies after the first and both applications were calculated. Significant differences were registered for final efficacy between both groups. When final efficacy of Group 1 was compared with efficacy after first application of Group 2, significant differences were found (P=0.0005). Same doses in different positions within the hive have different final efficacy. The higher efficacy was registered when the dispensers were placed over brood combs and on the hive bottom. It is suggested that efficacy is related to dispenser position within the hive.