A suplementação de vitamina C na estruturação do tecido conjuntivo de melanotência-maçã / Vitamin C supplementation in the structuring of connective tissue of red rainbowfish

Peixes cultivados mostram-se altamente sensíveis a dietas deficientes em ácido ascórbico com sinais clínicos que afetam o desempenho e a comercialização por provocar deformidades. Com objetivo de conhecer os níveis mínimos para a melanotênia-maçã, foram testadas seis rações isoaminoacídicas e isocalóricas com níveis variados de vitamina C ativa. Ao final dos 42 dias experimentais, 36 peixes foram analisados histologicamente quanto à porcentagem de tecido conjuntivo e fibras musculares a fim de determinar a influência da porcentagem de Vitamina C nesses índices. Apesar de as médias serem estatisticamente iguais do ponto de vista quantitativo, qualitativamente os níveis mais altos de vitamina C possibilitaram melhor estrutura tecidual. A desestruturação do tecido muscular é um indicativo da deficiência alimentar com ácido ascórbico...

Farmed fishes are highly sensitive to diets deficient in ascorbic acid with clinical symptoms that affect performance and commercialization for causing deformities. Aiming to meet the minimum levels for red rainbow fish, six isoaminoacid and isocaloric diets with varying levels of active vitamin C were tested. At the end of 42 days experimental period, 36 fishes were histologically analyzed for the percentage of connective tissue and muscle fibers in order to determine the influence of the Vitamin C percentage in those ratios. Although the averages are statistically indistinguishable from the quantitative point of view, qualitatively higher levels of vitamin C allow better tissue structure. The breakdown of muscle tissue is indicative for dietary deficiency of ascorbic acid...

Morphology of male reproductive system of two solitary bee species (Hymenoptera: Apidae)

Bees can form all levels of social organization, from solitary to advanced eusocial societies. Although 80 percent of the species exist as solitary species, most researches emphasize social species. This study focuses on the description of the male reproductive system of the solitary beesThygater analis (Lepeletier) and Melitoma segmentaria (Fabricius) and searches for traits that support behavioral and phylogenetic studies. The reproductive system of males were dissected, fixed in 2.5 percent glutaraldehyde in 0.1 M sodium cacodylate buffer pH 7.2 and post-fixed with 1 percent osmium tetroxide. The tissue was dissected and included for light microscopy. The species presented similar anatomical traits, including paired testicles, seminal vesicles, deferent ducts, accessory glands and an ejaculatory duct. Each testicle was composed of four follicles. In both species, a testicle and a seminal vesicle were surrounded by a joint capsule, forming a seminal vesicle-testicle complex. The two species presented accessory glands with very distinct morphological traits. The anatomic pattern and the histological traits of the reproductive system of the species studied were similar to those described for other bees. In addition, these traits can be used to differentiate species and allow inferences concerning their reproductive biology.