Enterolith with a bonefish spine nidus in a Brazilian cownose ray Rhinoptera brasiliensis (Müller & Henle) (Myliobatiformes: Rhinopteridae).

An adult female Brazilian cownose ray (Rhinoptera brasiliensis), housed in Ubatuba Aquarium died after loss of appetite period. During necropsy, an enterolith was discovered partially obstructing the intestinal lumen. Examination of the enterolith revealed a bonefish spine nidus. Enterolithiasis has been linked to multiple factors including diet, genetics, alkaline intestinal environments and, as in this particular case, the ingestion and retention of foreign bodies. The composition of this enterolith from a cownose ray was primarily monohydrocalcite. This short communication, apparently the first to report enterolithiasis in stingrays, emphasizes the need for post-mortem examinations of carcasses on macroscopic and microscopic levels.

Gonadal remodeling and hormonal regulation during sex change of juvenile dusky grouper Epinephelus marginatus (Teleostei, Serranidae), an endangered protogynous hermaphrodite fish.

Sex change was induced in Epinephelus marginatus juveniles using a nonsteroidal aromatase inhibitor (AI), a synthetic androgen (17α-methyltestosterone; MT), and a combination of both (MT + AI) in a 90-day experiment. A detailed remodeling of the gonads, the plasma level of gonadal steroids, and immunostaining of pituitary follicle-stimulating hormone (FSH), luteinizing hormone (LH), and somatolactin (SL) cells were analyzed. Sex inversion reached the final spermatogenesis stages using MT, while AI triggered spermatogenesis, but reaching only the spermatid stage. Estradiol (E2) levels did not change in fish treated with AI but decreased throughout the experimental period in animals treated with MT and MT + AI. Testosterone (T) levels increased in animals treated with MT during the first 60 days (and combined with AI in the first 30 days), decreasing in all experimental groups at 90 days, while AI-treated animals had increased plasma 11-ketotestosterone (11-KT) levels after 90 days. In control fish, FSH- and SL-producing cells (ir-FSH and ir-SL) were restricted to pars intermedia (PI) of the adenohypophysis. Pituitary ir-FSH cells were decreased at the end of the experimental period in all treatments compared with the CT animals. LH-producing cells (ir-LH) were present in proximal pars distalis (PPD) and pars intermedia (PI) of adenohypophysis and did not change after the experimental period. The decreased number of ir-FSH cells at the end of the experiment in all treatments could be related to the negative feedback loop triggered by the increase in natural and/or synthetic androgens.

Sanitary conditions of the Goliath grouper Epinephelus itajara in captivity on estuarine environment: case report / Condições sanitárias do mero Epinephelus itajara em cativeiro em ambiente estuarino: relato de caso

This study aimed to report the sanitary conditions through the hematological analysis of grouper E. itajara reared in captivity on estuarine conditions. Seven Goliath groupers (1,881.5±1,246.03g) were captured and kept in two tanks located on estuary. After 20 days, fish were collected for morphologic and hemato-physiologic evaluation. Two fish had clinical signs such as hemorrhagic spots and loss of scale due to agonistic behavior. Blood samples were collected, and the hematological parameters (biochemical, erythrogram and leukogram) were determined. Blood cells were characterized by their size, color and shape. Univariate statistic and principal components analysis were used to identify a hematological standard between fish with or without clinical signs. Four leukocyte types were found: lymphocyte, monocyte, neutrophil and basophil. Regardless of the clinical signs the cell morphology did not present any difference among the fish. However, there is a significant correlation between erythrocyte and lactate on fish with clinical signs. Thus, agonistics encountered among the fish is a stressing factor in captivity conditions making it necessary to have adequate management related to the size of fish and stocking density.(AU)

Este estudo avaliou as condições sanitárias do peixe mero E. itajara mantido sob cativeiro, em condições estuarinas, pelas análises hematológica e morfológica. Sete peixes (1.881,5±1.246,03g) foram capturados e mantidos em tanques localizados no estuário. Após 20 dias, os peixes foram coletados para avaliações morfológica e hematológica. Dois peixes tiveram sinais clínicos, como manchas hemorrágicas e perda de escamas devido ao comportamento agonístico entre os peixes. Amostras sanguíneas foram coletadas dos peixes anestesiados com auxílios de seringas umedecidas com EDTA 3%. Determinaram-se os parâmetros hematológicos (bioquímico, eritrograma e leucograma). Células sanguíneas foram caracterizadas por seu tamanho, cor e padrão. Estatística univariada e análises de componentes principais foram usadas para identificar um padrão hematológico entre os peixes com e sem sinais clínicos. Quatro tipos de leucócitos foram encontrados: linfócito, monócito, neutrófilo e basófilo. Os sinais clínicos não apresentaram diferença entre os peixes e a morfologia celular. Contudo, observou-se uma correlação entre os peixes com sinais clínicos e a quantidade de eritrócitos e lactato. Assim, encontros antagônicos entre os peixes são um fator estressante em condições de cativeiro, tornando-se necessário um manejo mais adequado relacionado ao tamanho dos indivíduos e à densidade de estocagem.(AU)

Does intensive feeding frequency affect growth performance of common snook Centropomus undecimalis (Bloch, 1792)? / A utilização de frequência alimentar elevada pode afetar o desempenho produtivo do robalo flecha Centropomus undecimalis (Bloch, 1792)?

Abstract Salt water recirculation systems using automatic feeders are a new frontier for marine aquaculture. It is possible to decrease the vulnerability of the traditional fish farming in open systems and reduce wasteful feeding and discharge of effluents, as well as increase the economic returns. An experiment with common snook fingerings (4.31 ± 1.42 g and 8.4 ± 1.0 cm) was performed. Three feeding treatments were evaluated: six, twelve and eighteen feeding times per day. Each treatment had three replications. Among the three tested frequencies (fed 6, 12 and 18 times a day), the feeding frequency of 12 times per day (every two hours) showed the best values of the parameters evaluated for production performance. The final weight values, condition factor, specific growth rate and daily weight gain of the treatment 12 feeding times per day were all significantly higher than the lower and higher frequencies. Our results demonstrate that high feeding frequency is not synonymous of higher performance, but is extremely necessary to find out the best range for the target species. Besides, this relationship between feeding frequency and growth performance might change over weight range. Therefore, future studies should address higher weight ranges for comparison to our results.

Resumo Sistemas de recirculação de água salgada utilizando alimentadores automáticos são uma nova fronteira para a aquicultura marinha. Possibilitam diminuir a vulnerabilidade dos cultivos em sistemas abertos e conferir redução de desperdício de ração e lançamento de efluentes, assim como elevar o retorno econômico. Foi realizado um experimento com juvenis de Robalo-flecha (4,31 ± 1,42 g e 8,4 ± 1,0 cm). Três frequências alimentares foram avaliadas: alimentação seis vezes ao dia; doze vezes ao dia, e; dezoito vezes ao dia. Cada tratamento teve três repetições. Dentre as três frequências avaliadas a frequência alimentar de 12 vezes ao dia foi a que apresentou os melhores valores para os parâmetros zootécnicos avaliados. Os valores obtidos de peso final, fator de condição, taxa de crescimento específico e ganho de peso diário foram todos maiores para a frequência de 12 vezes ao dia do que os obtidos para as frequências maior e menor. Nossos resultados demonstram que elevadas frequências alimentares não são sinônimo de melhor desempenho produtivo, mas é extremamente importante conhecer a frequência ideal para a espécie a ser cultivada. Além disto, a relação entre frequência alimentar e crescimento pode mudar de acordo com a faixa de peso dos indivíduos. Desta forma, é extremamente importante que trabalhos futuros avaliem as frequências aqui estudadas para comparar os resultados em indivíduos maiores.

Use of eugenol for anesthesia of lesser guitarfish Zapteryx brevirostris (Rhinobatidae) / Uso de eugenol para anestesia de raia-viola Zapteryx brevirostris (Rhinobatidae)

Abstract Anesthesia can be utilized as a non-lethal procedure to allow easy handling of teleosts and elasmobranchs in captivity or in the wild. For this, anesthetic protocols need to be established according to the species. The aim of this study was to determine the ideal concentration of eugenol for anesthesia of Zapteryx brevirostris. Four concentrations were tested: 21.25, 42.50, 85.00 and 170.00 mg L-1 (ratio of 1:5 with absolute ethanol). The perfect concentration of eugenol for this species was 85.0 mg L-1 , which enabled up to 300 seconds of work on the fish, without any response to handling.

Resumo A anestesia pode ser utilizada como um procedimento não letal que facilita o manejo de teleósteos e elasmobrânquios de cativeiro e de vida livre. Para isso, protocolos anestésicos devem ser estabelecidos de acordo com a espécie. O objetivo deste trabalho foi determinar a concentração ideal do eugenol para anestesiar Zapteryx brevirostris. Foram testadas as concentrações de 21,25; 42,50; 85,00 e 170,00 mg L-1 (1:5 de álcool absoluto). A concentração de 85,0 mg L-1 de eugenol foi a mais adequada para a espécie, permitindo uma janela de trabalho de até trezentos segundos com o animal não respondendo ao manejo.

Does intensive feeding frequency affect growth performance of common snook Centropomus undecimalis (Bloch, 1792)?

Salt water recirculation systems using automatic feeders are a new frontier for marine aquaculture. It is possible to decrease the vulnerability of the traditional fish farming in open systems and reduce wasteful feeding and discharge of effluents, as well as increase the economic returns. An experiment with common snook fingerings (4.31 ± 1.42 g and 8.4 ± 1.0 cm) was performed. Three feeding treatments were evaluated: six, twelve and eighteen feeding times per day. Each treatment had three replications. Among the three tested frequencies (fed 6, 12 and 18 times a day), the feeding frequency of 12 times per day (every two hours) showed the best values of the parameters evaluated for production performance. The final weight values, condition factor, specific growth rate and daily weight gain of the treatment 12 feeding times per day were all significantly higher than the lower and higher frequencies. Our results demonstrate that high feeding frequency is not synonymous of higher performance, but is extremely necessary to find out the best range for the target species. Besides, this relationship between feeding frequency and growth performance might change over weight range. Therefore, future studies should address higher weight ranges for comparison to our results.

Use of eugenol for anesthesia of lesser guitarfish Zapteryx brevirostris (Rhinobatidae).

Anesthesia can be utilized as a non-lethal procedure to allow easy handling of teleosts and elasmobranchs in captivity or in the wild. For this, anesthetic protocols need to be established according to the species. The aim of this study was to determine the ideal concentration of eugenol for anesthesia of Zapteryx brevirostris. Four concentrations were tested: 21.25, 42.50, 85.00 and 170.00 mg L-1 (ratio of 1:5 with absolute ethanol). The perfect concentration of eugenol for this species was 85.0 mg L-1 , which enabled up to 300 seconds of work on the fish, without any response to handling.

Refrigeração do sêmen da garoupa-verdadeira Epinephelus marginatus / Refrigerated storage of dusky grouper Epinephelus marginatus sperm

Foram estudados diferentes diluentes no processo de refrigeração do sêmen da garoupa-verdadeira. Inicialmente, a taxa e a duração da motilidade e a concentração espermática foram avaliadas, caracterizando a qualidade do sêmen fresco. Para os testes de refrigeração a 4ºC, diferentes diluentes foram testados em atmosfera normal e modificada (100% oxigênio). O sêmen fresco apresentou concentração espermática de 3,1±0,2 x 109 células mL-1, motilidade média de 90%, permanecendo móvel, em média, por 3.060 segundos. No experimento de refrigeração, a taxa e a duração média da motilidade foram mantidas adequadas durante 144 horas para o diluente A (70%; 3100 segundos) em atmosfera normal. Na atmosfera modificada, a qualidade do sêmen caiu drasticamente durante as primeiras 24 horas, independentemente do diluente empregado, não propiciando vantagem em sua utilização. A refrigeração do sêmen da garoupa-verdadeira permite manter por até 144 horas uma apropriada qualidade espermática.(AU)

This study aimed to evaluate different extenders in refrigerated storage of dusky grouper sperm. Initially, motility rate, motility time, and sperm density were analyzed to characterize the fresh sperm quality. Different diluents were used in the refrigerated storage sperm at 4ºC in normal atmosphere and modified atmosphere (100% oxygen). The fresh sperm has a spermatozoa density of 3.1±0.2 x 109 spermatozoa mL-1, motility rate 90% and motility time of 3,060 seconds. In the experiment of refrigerated storage, the motility rate and the motility time were maintained appropriate for 144 hours for the extender A (70%; 3,100 seconds) in normal atmosphere. In the modified atmosphere, the sperm quality decreased drastically during the first 24 hours, independently of the diluent used, not propitiating advantages. The refrigerated sperm of dusky grouper is a viable alternative for the short-term storage, being possible, to maintain for up to 144 hours an appropriate sperm viability.(AU)

Rediscovering hermaphroditism in Grammatidae with the description of the testicular gland in Brazilian Basslet Gramma brasiliensis / Redescobrindo o hermafroditismo em Grammatidae com a descrição da glândula testicular de Gramma brasiliensis

Abstract Many aspects of sex change in reef fishes have been studied, including behavior and social organization. However, gonad histology remains the most robust way to identify sexual patterns in fishes. Some uncommon tissues remain poorly described, such as the accessory gonadal structures found in species from the Gobiidae family, which are rare in other bony fishes. This is the first report of the testicular gland in Gramma brasiliensis and for the Grammatidae family. Between April 2011 and February 2012 eighty specimens were collected during four dive campaigns on the Taipus de Fora reef (13°56’20”S 38°55’32”W), Bahia, Northeast Brazil, and their sex was determined. Thirteen per cent of the active-females and 90% of the active-males had testicular gland tissue in their ovotestis. This discovery led to additional research into the characteristics of the gland tissue and its relationship with gonadal maturation. Three patterns of testicular gland development were found in Brazilian basslet ovotestis. Both ova and sperm-producing gonad contained testicular gland tissue, and the appearance of this tissue seems to be the first modification of ovotestis tissue marking the beginning of the protogynous sex-change process in G. brasiliensis.

Resumo Diversos aspectos da troca de sexo em peixes recifais vem sendo estudados, incluindo comportamentos e organização social. Entretanto, a histologia das gônadas continua sendo a maneira mais robusta para se identificar padrões sexuais em peixes. Alguns tecidos incomuns, tais como as estruturas anexas a gônada encontradas em espécies da família Gobiidae e raras em outras espécies são pouco estudados. Este trabalho é a primeira descrição da glândula testicular em Gramma brasiliensis e para a família Grammatidae. Entre abril de 2011 e fevereiro de 2012, oitenta espécimes foram coletados durante quatro amostragens no recife de Taipus de Fora (13°56’20”S 38°55’32”W), Bahia, Brasil, e tiveram seus sexos determinados. Treze por cento das fêmeas ativas e noventa por cento dos machos ativos apresentaram tecido da glândula testicular em suas gônadas. Esta descoberta levou ao estudo da características dessa estrutura e sua relação com a maturação gonadal. Foram identificados três padrões de desenvolvimento da glândula testicular nas gônadas do Gramma brasiliensis. Tanto as gônadas produtoras de espermatozoides quanto as de oócitos apresentaram tecido da glândula testicular, e o surgimento desse tecido parece ser a primeira modificação gonadal do início da troca de sexo protogínica em G. brasiliensis.

Rediscovering hermaphroditism in Grammatidae with the description of the testicular gland in Brazilian Basslet Gramma brasiliensis.

Many aspects of sex change in reef fishes have been studied, including behavior and social organization. However, gonad histology remains the most robust way to identify sexual patterns in fishes. Some uncommon tissues remain poorly described, such as the accessory gonadal structures found in species from the Gobiidae family, which are rare in other bony fishes. This is the first report of the testicular gland in Gramma brasiliensis and for the Grammatidae family. Between April 2011 and February 2012 eighty specimens were collected during four dive campaigns on the Taipus de Fora reef (13°56'20"S 38°55'32"W), Bahia, Northeast Brazil, and their sex was determined. Thirteen per cent of the active-females and 90% of the active-males had testicular gland tissue in their ovotestis. This discovery led to additional research into the characteristics of the gland tissue and its relationship with gonadal maturation. Three patterns of testicular gland development were found in Brazilian basslet ovotestis. Both ova and sperm-producing gonad contained testicular gland tissue, and the appearance of this tissue seems to be the first modification of ovotestis tissue marking the beginning of the protogynous sex-change process in G. brasiliensis.

Sperm cryopreservation of lane snapper Lutjanus synagris (Linnaeus, 1758).

This study aims developing and evaluate a protocol of semen cryopreservation of the lane snapper Lutjanus synagris. Firstly, sperm motility rate, motility time, density and spermatocrit were appraised to characterize the sperm quality of the lane snapper. The effect of three extenders with distinct ionic compositions and pH values combined with seven concentrations of cryoprotector dimethylsulfoxide (0; 2.5; 5.0; 7.5; 10.0; 12.5 e 15.0%), five cooling rates (110, 90, 60, 45 e 30°C -min), nine equilibration time (1; 2,5; 5; 10; 15; 20; 25; 30 e 60 minutes) e five dilutions ratio (1:1; 1:3; 1:6; 1:10 e 1:20) on the sperm motility rate and motility time were analyzed. Fertilization test was accomplished to evaluate the viability of the cryopreserved sperm. The higher sperm motility rate and motility time (P<0.05) was achieved by combining extender with pH 8.2 with 10% concentration of dimethylsulfoxide and cooling rate 60°C -min, 1 minute of equilibration time and 1:3 (v/v) dilution ratio. The use of cryopreserved sperm presented fertilization rates >60% validating the present protocol for lane snapper. The cryoconserved sperm of lane snapper is a viable alternative, being possible to maintain appropriate sperm viability.

Parasite fauna of wild and cultured dusky-grouper Epinephelus marginatus (Lowe, 1834) from Ubatuba, southeastern Brazil / Fauna parasitária da garoupa selvagem e de cultivo Epinephelus marginatus (Lowe, 1834) em Ubatuba, sudeste do Brasil

This study aimed at identifying and quantifying the parasites of wild and cultured dusky grouper Epinephelus marginatus. During a year and thereby all four seasons, 20 wild and 20 cultured groupers were examined for the presence of parasites, except in the last season, in which 19 wild and 20 cultured fish were examined, totalling 159 groupers analysed from Ubatuba, southeastern Brazil. Prevalence, mean intensity of infection, mean abundance and mean relative dominance were calculated. Five species of parasites were identified in fish from both origins: Pseudorhabdosynochus beverleyburtonae (Monogenea), Neobenedenia melleni (Monogenea), Pseudempleurosoma sp. (Monogenea), Helicometrina nimia (Digenea) and larvae of Contracaecum sp. (Nematoda). The prevalence of ectoparasites, in most cases, was higher than endoparasites. The most abundant parasite was the monogenea Pseudorhabdosynochus beverleyburtonae in both wild and cultured fish, along all seasons. Neobenedenia melleni was observed in wild and cultured fish in all seasons, with a gradual increase in the number of parasites from the coldest to the hottest seasons, with the highest prevalence and mean intensity in the summer. Helicometrina nimia was found in all seasons in both wild and cultured fish, except for summer, where its presence was detected only in wild fish. Pseudempleurosoma sp. and larvae of Contracaecum sp. showed low prevalence occurring in wild and cultured fish in the autumn and spring, respectively. This study revealed high intensities of potentially pathogenic parasites that could favour disease outbreaks in culture conditions.

Este estudo teve como objetivo identificar e quantificar os parasitos da garoupa verdadeira Epinephelus marginatus selvagem e cultivada. Durante um ano, nas quatro estações, 20 garoupas selvagens e 20 cultivadas foram examinadas quanto à presença de parasitos, exceto na última estação, em que foram examinados 19 peixes selvagens e 20 cultivados, totalizando 159 peixes examinados em Ubatuba, Sudeste do Brasil. A prevalência, intensidade média de infecção, abundância média and dominância média relativa foram calculados. Cinco espécies de parasitos foram identificadas nos peixes de ambas as origens: Pseudorhabdosynochus beverleyburtonae (Monogenea), Neobenedenia melleni (Monogenea), Pseudempleurosoma sp. (Monogenea), Helicometrina nimia (Digenea) e larvas de Contracaecum sp. (Nematoda). A prevalência de ectoparasitos foi, na maioria das vezes, maior do que a de endoparasitos. O parasito mais abundante foi o monogenea Pseudorhabdosynochus beverleyburtonae em ambos os peixes selvagens e cultivados, durante todas as estações. Neobenedenia melleni foi observado e, peixes selvagens e cultivados em todas as estações, com aumento gradativo no número de parasitos das estações mais frias para as mais quentes, com as maiores prevalências e intensidades médias no verão. Helicometrina nimia foi encontrado em todas as estações em ambos os peixes selvagens e cultivados, exceto no verão, em que foi observada sua presença apenas em peixes selvagens. Pseudempleurosoma sp. e larvas de Contracaecum sp. apresentaram baixas prevalências, ocorrendo em peixes selvagens e cultivados no outono e na primavera, respectivamente. Este estudo revelou altas intensidades de parasitos potencialmente patogênicos que podem favorecer surtos de doenças em situações de cultivo.

Parasite fauna of wild and cultured dusky-grouper Epinephelus marginatus (Lowe, 1834) from Ubatuba, southeastern Brazil.

This study aimed at identifying and quantifying the parasites of wild and cultured dusky grouper Epinephelus marginatus. During a year and thereby all four seasons, 20 wild and 20 cultured groupers were examined for the presence of parasites, except in the last season, in which 19 wild and 20 cultured fish were examined, totalling 159 groupers analysed from Ubatuba, southeastern Brazil. Prevalence, mean intensity of infection, mean abundance and mean relative dominance were calculated. Five species of parasites were identified in fish from both origins: Pseudorhabdosynochus beverleyburtonae (Monogenea), Neobenedenia melleni (Monogenea), Pseudempleurosoma sp. (Monogenea), Helicometrina nimia (Digenea) and larvae of Contracaecum sp. (Nematoda). The prevalence of ectoparasites, in most cases, was higher than endoparasites. The most abundant parasite was the monogenea Pseudorhabdosynochus beverleyburtonae in both wild and cultured fish, along all seasons. Neobenedenia melleni was observed in wild and cultured fish in all seasons, with a gradual increase in the number of parasites from the coldest to the hottest seasons, with the highest prevalence and mean intensity in the summer. Helicometrina nimia was found in all seasons in both wild and cultured fish, except for summer, where its presence was detected only in wild fish. Pseudempleurosoma sp. and larvae of Contracaecum sp. showed low prevalence occurring in wild and cultured fish in the autumn and spring, respectively. This study revealed high intensities of potentially pathogenic parasites that could favour disease outbreaks in culture conditions.

Evaluation of a new tablet formulation based on Bacillus thuringiensis sorovar. israelensis for larvicidal control of Aedes aegypti.

The effect of sunlight on the efficacy and persistence of an experimental tablet formulation based on Bacillus thuringiensis sorovar. israelensis (C4P1) was evaluated against Aedes aegypti larvae under simulated field conditions. The initial mortality ranged from 93 to 100%, and the residual activity (> or = 70% mortality) recorded in containers exposed to sunlight or shade were, respectively, 13-35 days and 40-54 days. The results suggest that C4P1 can provide long-term larvicidal effect and operational advantages.