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Understanding the effect of pesticides on the survival of honeybee colonies is important because these pollinators are reportedly declining globally. In the present study, we examined the changes in the head proteome of nurse honeybees exposed to individual and combined pesticides (the fungicide pyraclostrobin and the insecticide fipronil) at field-relevant doses (850 and 2.5 ppb, respectively). The head proteomes of bees exposed to pesticides were compared with those of bees that were not exposed, and proteins with differences in expression were identified by mass spectrometry. The exposure of nurse bees to pesticides reduced the expression of four of the major royal jelly proteins (MRJP1, MRJP2, MRJP4, and MRJP5) and also several proteins associated with carbohydrate metabolism and energy synthesis, the antioxidant system, detoxification, biosynthesis, amino acid metabolism, transcription and translation, protein folding and binding, olfaction, and learning and memory. Overall, when pyraclostrobin and fipronil were combined, the changes in protein expression were exacerbated. Our results demonstrate that vital proteins and metabolic processes are impaired in nurse honeybees exposed to pesticides in doses close to those experienced by these insects in the field, increasing their susceptibility to stressors and affecting the nutrition and maintenance of both managed and natural colonies.Pollination is an indispensable service provided mainly by wild insects and farmed honeybees (Apis mellifera, Linnaeus, 1758) that supports biodiversity, agriculture, and food security 1,2 . There is growing concern over the reported global reduction in these insects, which compromises this ecological service 2-8 .The maintenance of honeybee colonies is dependent upon specialised tasks performed by individuals of different roles; thus, stress-related dysfunction of specialised workers can affect entire colonies 9,10 . Pesticides, phytochemicals, pathogens, and parasites are among the main stressors for honeybees, and exposure can lead to dysfunctions that change the behaviour, anatomy, and/or physiology of these insects 10 . Previous reviews have indicated that pesticide exposure negatively affects the maintenance of wild and commercial honeybee populations 5,11,12 . Exposure of bees to field-relevant doses of pesticides that are frequently found in plants visited by these insects compromise essential functions, such as cognition, foraging, navigation, homing, and memory [13][14][15] . Exposure also causes physiologic changes in individual bees that compromises colony maintenance 9,15-18 .Nutrition is a key factor in colony maintenance 19 and caste differentiation of honeybees, and is essential for the full development and activity of mandibular and hypopharyngeal (or brood-food) glands in the head of 6-day-old worker bees 20-22 . These glands are responsible for the production of royal jelly (RJ), a secretion used to nourish all bee larvae until 3 days old, after which only the queen larvae are fed with RJ throughout larval and a...

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ResumoO presente trabalho avaliou a influência da adição de urucum como agente pigmentante sobre as características de coloração da pele, músculo e desempenho produtivo de Carassius auratus, criados em hapas de 0,15 m 3 (dimensões de 0,50 x 0,50 x 0,65 m), dispostos no interior de um tanque de alvenaria circular de 25 m 3. Foram utilizados 336 alevinos de C. auratus distribuídos inteiramente ao acaso em 28 hapas, com sete tratamentos e quatro repetições, com 12 peixes por unidade. Os níveis de adição de urucum foram 0,0; 0,25; 0,50; 1,00; 2,00; 4,00 e 8,00%. Os peixes com peso inicial médio de 1,12 ± 0,18 g e comprimento de 4,31 ± 0,44 cm, foram alimentados as 08, 11, 14 e 17 horas. A característica colorimétrica de b* (amarelo) mostrou valores significativos aos 96 e 141 dias no sistema de coordenadas Hunter com adição de 2,0 e 1,0% de urucum na dieta, respectivamente e, no sistema de coordenadas CMYK aos 96 dias para C (ciano) e aos 141 dias para Y (amarelo) com adição de 8,0 e 2,0% de urucum na dieta respectivamente. Observaram-se diferenças (P<0,05) para peso final médio, ganho em peso médio, conversão alimentar aparente, taxa de crescimento diário e eficiência alimentar. Recomenda-se uma dieta contendo 1,0% de adição de urucum para C. auratus para o melhor desempenho e de 1,0 a 4,0% de adição de urucum para intensificação luminosa da pele dos peixes. Palavras-chave: Aquicultura, carotenóides, peixes ornamentais, piscicultura AbstractThis study evaluated the effect of adding annatto as agent pigmentation on the staining characteristics of the skin, muscle and productive performance of Carassius auratus, reared in 0.15 m 3 (dimensions 0.50 x 0.50 x 0.65 m) hapas disposed within a circular masonry tank of 25 m 3 . We used 336 C. auratus fingerlings completely randomized design in 28 hapas with seven treatments and four replicates with 12 fish per unit. The addition of annatto levels were 0.0, 0.25, 0.50, 1.00, 2.00, 4.00 and 8.00%. Fish with an average initial weight of 1.12 ± 0.18 g and length of 4.31 ± 0.44 cm, were fed the 08, 11, 14 and 17 hours. The b * colorimetric characteristics (yellow) showed significant at 96 and 141 days in the Hunter coordinate system with the addition of 2.0 and 1.0% annatto in the diet, respectively, and the coordinate system of CMYK and 96 days for C (cyan), and 141 days for the Y (yellow), with the addition of 8.0 to

Bioaccumulative metals such as mercury are found in increasing amounts in fish and their consumers. In the region of the Madeira River, in the Brazilian Amazon, mercury (Hg) is a predominant contaminant in the aquatic ecosystem. There is therefore a need to find specific biomarkers of mercury toxicity in fish to monitor contaminations. Here, mercury-bound proteins were identified in the liver tissues of fishes Mylossoma duriventre and Brachyplatystoma rousseauxii. Mercury was quantified in liver tissue, pellets and protein spots by graphite furnace atomic absorption. Proteins were fractionated by two-dimensional polyacrylamide gel electrophoresis and identified by mass spectrometry with electrospray ionization. We identified nine proteins linked to mercury and that presented biomarker characteristics of mercury. Among the proteins identified, isoforms of parvalbumin, ubiquitin-40S ribosomal protein S27a, brain-specific angiogenesis inhibitor 1-associated protein 2-like protein 2 and betainehomocysteine S-methyltransferase 1 are notable for having the molecular function of binding to metallic ions.