Diferentes granulometrias de rações sobre o ganho de peso, crescimento, sobrevivência e reversão sexual para tilápias-do-Nilo (Oreochromis niloticus)

The aim of this work was to evaluate the effects of three different diameters of crumble diets (0.25, 0.35 and 0.50 mm) on weight gain, growing, survival and sexual proportion to Nile tilapia (Oreochromis niloticus) larvae with 30, 60 and 90 days of age. In the first 30 days of age larvae were submitted to sex reversion with diets containing the hormone 17 α-methyltestosterone in a dosage of 60mg/kg of ration, respecting the different diameters and after this period, larvae were measured, weighed and counted for calculation of survival taxes. For the biometrical parameters as weight and total length a completely randomized design was used in subdivided installments with three treatments and three repetitions, considering installments the three diameters of diet and the sub installments, the three ages. In the end of this study, fish fed with diets of grain diameters 0.35 and 0.25 mm obtained the best results for weight gain (14.42 g and 13.36 g) and total length (83.13 mm and 82.72 mm), although these results were not statistically significant, and diets with grain diameters 0.50 and 0.35 mm resulted in 96,66 % and 93,33% of males, respectively, after histological analysis of gonads, without statistics differences between the treatments.O objetivo deste trabalho foi avaliar os efeitos de três diferentes granulometrias de rações fareladas (0,25, 0,35 e 0,50 mm) sobre o ganho de peso, crescimento, sobrevivência e proporção sexual para larvas de tilápia-do-Nilo (Oreochromis niloticus) aos 30, 60 e 90 dias de idade. Nos primeiros 30 dias de vida, as larvas foram revertidas com rações contendo hormônio 17 α-metiltestosterona na dosagem de 60 mg/kg de ração, respeitando-se as diferentes granulometrias e após este período, foram medidas, pesadas e contadas para cálculo da taxa de sobrevivência. Para as variáveis biométricas de peso e comprimento total, foi utilizado o delineamento inteiramente casualizado (DIC), em parcelas subdivididas, com três tratamentos e três repetições, considerando-se parcelas as três granulometrias de ração e subparcelas as três idades. Ao término do estudo, os peixes alimentados com as granulometrias 0,35 e 0,25 mm, obtiveram os melhores resultados para o ganho de peso (14,42 g e 13,36 g) e comprimento total (83,13 mm e 82,72 mm), não diferindo estatisticamente e as rações com diâmetros de grão 0,50 e 0,35 mm resultaram em 96,66% e 93,33% de machos, respectivamente, após análise histológica das gônadas, sem diferenças estatísticas entre os tratamentos

Viabilidade de embriões de piracanjuba (Brycon orbignyanus) submetidos a diferentes protocolos de resfriamento

O gênero Brycon tem despertado grande interesse nas instituições de pesquisa, não só pela excelente qualidade e sabor da carne, mas também por características adequadas à pesca esportiva, rápido crescimento e ganho de peso. A piracanjuba tem sofrido drástica redução dos estoques em decorrência da ação antrópica estando na lista do IBAMA de espécies ameaçadas de extinção. A criopreservação de gametas e embriões de espécies migradoras e espécies raras surge como uma alternativa para a reprodução, repovoamento, criação de banco genético, transporte e possível obtenção de larvas ao longo do ano. Assim, este trabalho teve por objetivo ampliar os conhecimentos de criogenia utilizando embriões de piracanjuba (Brycon orbignyanus), com o intuito de estabelecer um protocolo de resfriamento para ser utilizado em projetos de reprodução e conservação desta espécie. Após a obtenção dos embriões por meio de reprodução induzida, estes, quando na fase de fechamento do blastóporo, foram contados e subdivididos em parcelas, considerando como unidade experimental um tubo (vacutainer) contendo 100 embriões. Cada tratamento teve oito repetições. Com exceção dos grupos controles, os demais tratamentos foram submetidos a diferentes combinações e concentrações de crioprotetores (sacarose, metanol, etilenoglicol e DMSO), diferentes temperaturas (0,0±2,0°C e 8,0±2,0ºC) e tempos de estocagem em refrigerador (6h, 10h, 24h, 72h, 168h). Transcorridos os tempos de estocagem, os embriões foram aclimatados, rehidratados e transferidos para incubadoras para monitoramento do desenvolvimento e aferições das taxas de eclosão, sobrevivência e deformidade. Para avaliar o desenvolvimento de tecidos e células após a realização do experimento, amostras foram fixadas, observadas em estereomicroscópio e...The genus Brycon have aroused great interest of research institutions, not only for the excellent quality and flavor of the meat, but also for characteristics suited to sport fishing, quick growth and weight gain. Piracanjuba suffers drastic reduction in natural environment as a result of human action and is in the list of endangered species of IBAMA. The cryopreservation of gametes and embryos of migratory and rare species is an alternative to reproduction, repopulation, creating genetic database, transport of larvae and obtainment of larvae throughout the year. The aim of this study is expand the knowledge of cryogenics using embryos of piracanjuba (Brycon orbignyanus) and establishing a cooling protocol to be used in projects of reproduction and conservation of this species. After obtaining embryos from induced reproduction, those ones that were in this phase of blastopore closuring, were colected, counted and divided into groups, considering as experimental unit each tube (vacutainer) containing 100 embryos. Each treatment had eight replications. Except for the control groups, the other treatments were subjected to different combinations and concentrations of cryoprotectants (sucrose, methanol, ethylene glycol and DMSO), different temperatures (0,0 ± 2,0ºC and 8,0 ± 2,0°C) and storage time on refrigerator (6h, 10h, 24h, 72h, 168h). Elapsed times of storage, the embryos were acclimated, washed and transferred to incubators for monitoring the development of measurements and hatching rates, survival and deformity. To evaluate the development of tissues and structures after the experiment, samples were put on fixative solution and observed under stereomicroscope, and after that were processed and analyzed by light microscopy and transmission electron microscopy. It was observed that... (Complete abstract click electronic access below

Early development of Astronotus ocellatus under stereomicroscopy and scanning electron microscopy

Astronotus ocellatus, popularly known as Oscar, is a cichlid fish from the Amazon basin (Brazil) with a great potential for fish farming. The aim of this research is to describe the morphology of eggs and larvae of A. ocellatus under stereomicroscopy and scanning electron microscopy. Eggs from natural spawnings were taken to hatcheries, collected at previously established time periods and then analysed. Oscar's eggs are demersal, adhesive and fragile to touch, with a slightly oval shape. The fertile eggs are yellowish in colour and when unfertilized are a white opaque colour. In the initial collection (IC), the majority of eggs were found to be at the gastrula phase with 30% epiboly. At 12 h after the IC, the formation of the embrionary axis and somites was observed, followed by differentiation of the tail and of the head. Fifteen hours after the IC, the emergence of the optic and otic vesicles, and of adhesive glands and the yolk pigmentation was observed. Larval hatching took place between 46 and 58 h after the first collection, at an average temperature of 27.45 +/- 2.13 degrees C. The larval stage was characterized by the development of the heart, fins, branchial apparatus, neuromasts, taste buds and adhesive glands on the head. Larval development to yolk absorption took a period of 257 h. These results provide important information for reproduction, rearing and preservation of A. ocellatus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Diferentes granulometrias de rações sobre o ganho de peso, crescimento, sobrevivência e reversão sexual para tilápias-do-Nilo (Oreochromis niloticus)

The aim of this work was to evaluate the effects of three different diameters of crumble diets (0.25, 0.35 and 0.50 on weight gain, growing, survival and sexual proportion to Nile tilapia (Oreochromis niloticus) larvae with 30, 60 and 90 days of age. In the first 30 days of age larvae were submitted to sex reversion with diets containing the hormone 17[alpha]-methyltestosterone in a dosage of 60mg/kg of ration, respecting the different diameters and after this period, larvae were measured, weighed and counted for calculation of survival taxes. For the biometrical parameters as weight total length a completely randomized design was used in subdivided installments with three treatments and repetitions, considering installments the three diameters of diet and the sub installments, the three ages. In the end of this study, fish fed with diets of grain diameters 0.35 and 0.25 mm obtained the best results for weight gain (14.42g and 13.36 g) and total length (83.13 mm and 82.72 mm), although these results were not statistically significant, and with grain diameters 0.50 and 0.35 mm resulted in 96,66 % and 93,33% of males, respectively, after histological an, of gonads, without statistics differences between the treatments

Efetividade de métodos de identificação sexual em tilápias-do-nilo (oreochromis niloticus) revertidas sexualmente com hormônio em ração com diferentes granulometrias

Three methods of sexual identification were evaluated in Nile tilapia (Oreochromis niloticus) at ages of 30, 60 and 90 days that were submitted to sexual reversion under administration of androgen hormone 17 alpha-methyltestosterone added to crumble diets with different granules sizes (0.25, 0.35 and 0.50 mm) in dosage of 60mg/kg. The techniques of sexual identification employed were: a) Macroscopic examination of urogenital papilla; b) Microscopic examination of gonads through stain with carmine-acetate and c) Microscopic examination of gonads through histological routine. In the presence of three methods of sexual identification evaluated, histology of gonads has shown the most confident diagnosis. The grain diameters of rations did not interfere in morphological characteristics of gonads, neither in secondary sexual characters of fish.O presente trabalho avaliou três métodos de identificação do sexo em tilápia-do-nilo (Oreochromis niloticus), nas idades de 30, 60 e 90 dias que foram revertidas mediante a administração do hormônio androgênico 17 α-metiltestosterona incorporado às rações fareladas com diferentes granulometrias (0,25, 0,35 e 0,50 mm) na dosagem de 60mg/kg de ração. As técnicas de sexagem testadas foram: exame macroscópico da papila urogenital, exame microscópico das gônadas coradas a fresco com acetato-carmim e exame microscópico das gônadas pela rotina histológica. Perante os três métodos de sexagem avaliados, a histologia das gônadas obteve o diagnóstico mais seguro. As granulometrias das rações utilizadas não interferiram nas características morfológicas das gônadas e nem nos caracteres sexuais secundários dos peixes

Hatching, survival and deformities of piracanjuba (Brycon orbignyanus) embryos subjected to different cooling protocols

Groups of one hundred Brycon orbignyanus embryos at the stage of blastopore closure were subjected to different cooling protocols. Different combinations and concentrations of cryoprotectants were tested: sucrose, methanol, ethylene glycol and dimethyl sulfoxide (Me2SO); at different temperatures (0.0 +/- 2.0 degrees C and 8.0 +/- 2.0 degrees C) and refrigeration times (6, 10, 24, 72 and 168 h), with the exception of the positive control (incubation without previous cooling). At the end of each refrigeration time, the embryos were acclimatized, rehydrated and incubated to determine hatching, survival and deformity rates. Morphological analysis of embryos was also carried out. The results showed that temperature and refrigeration time are critical factors for embryo survival. No embryos survived after 24, 72 and 168 h of refrigeration. Furthermore, when the refrigeration time increased from 6 to 10 h and the temperature decreased from 8.0 +/- 2.0 degrees C to 0.0 +/- 2.0 degrees C, mortality rates increased significantly. It was also found that in all protocols dead eggs and/or larvae with some degree of deformity were present. The main larval deformities observed were the malformation of the head, tail, yolk sac, vertebral column and eyes. (C) 2014 Elsevier Inc. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Sociobehavioral, Biological, and Health Characteristics of Riverside People in the Xingu Region, Pará, Brazil

This study aimed to evaluate the sociodemographic, behavioral, and biological profile and its relationship with the emergence of chronic non-communicable diseases in riverside populations in the Xingu region, Pará, Brazil. Characteristics related to health indicators and which risk factors are considered most important were analyzed. This is a cross-sectional, exploratory, and descriptive study. The sample consisted of riverside people of over 18 years of both sexes. The sample size (n = 86) was calculated with a confidence level of 95% and a sample error of 5%. The K-means clustering algorithm was adopted through an unsupervised method to divide the groups, and the values were expressed as a median. For continuous and categorical data, the Mann-Whitney and chi-square tests were used, respectively, and the significance level was set at p p p p < 0.05), and waist–hip ratio, with values above the expected being observed in both groups. The factors considered important so as to be considered to have good health condition or not were the educational and social conditions of these communities, and one part of the riverside population was considered healthier than the other

Induced reproduction and early development histology of Oscar Astronotus ocellatus (Agassiz, 1831)

Oscar (Astronotus ocellatus) is an important fish from the Amazon Basin that has great potential for fish farming, human consumption, sport fishing and fish keeping. This study aimed to evaluate the effect of two hormonal treatments on the induction of artificial reproduction in broodstock and to describe the histological development of embryos and larvae. Broodstocks were selected and induced using two different hormones: (i) extract of carp pituitary (ECP); and (ii) synthetic human chorionic gonadotropin (hCG). Spawnings were transferred to hatcheries, collected at pre-established times, processed and analysed by histology. Astronotus ocellatus did not respond well to induced reproduction. From 16 couples of breeding fish, only five out of the eight females released oocytes after the hormonal action time, three with hCG and two with ECP; just one male responded positively to hCG. Oscar eggs were oval, and semi-adhesive, the yolk contained granules, and egg diameter was approximately 1.65 +/- 0.057 to 1.98 +/- 0.038 mm. Development from the initial collection (IC) point until the total absorption of the yolk lasted 315 h, at an average temperature of 27.45 +/- 2.13 degrees C. Several events marked embryonic and larval development, including the formation of the optic cup, forebrain, otic vesicle and cephalic divisions. The newly hatched larvae had non-pigmented eyes, and a closed mouth and anus, as well as the presence of adhesive glands on the head. Larval development was characterized by formation of the heart, liver, gaseous bladder, gills, pronephros, brain, fins and also the digestive tract. These results provide important information for the rearing and reproduction of A. ocellatus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Maternal age influences on reproductive rates in Nile tilapia (Oreochromis niloticus)

In this study we examined the effects of the maternal age on the fecundity (absolute and relative), egg production, and fertilization rates of Nile tilapia (Oreochromis niloticus). Females were divided into three groups: Group 1 (6 years old), Group 2 (3 years old), and Group 3 (8 months old). Males of eight months were used in all groups. Twice a week, the females'mouths were examined, and if they had eggs, these were removed and transferred to 2-L incubators. No difference was observed in the absolute fecundity between the different maternal age groups. Relative fecundity and egg production was greater in Group 3 (8 months) and fertilization rates were lower in Group 1 (6 years). Younger tilapias are more viable for egg production, because they have better reproductive indexes.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq