Biology and Potential Use of Pacific Grenadier, Coryphaenoides acrolepis, off California

Grenadiers (family Macrouridae) are the most abundant fish on most continental slope areas worldwide. Off California the Pacific grenadier, Coryphaenoides acrolepis, occurs in relatively large numbers and may have marketing potential. This repon provides information on the biology of the species and catch results from a number of scientific cruises. Catch data on several other species found together with Pacific grenadier, panicularly sablefish, Anoplopoma fimbria, are also given. The fish were caught with a bottom trawl (15 trawls), and with free-vehicle longline gear (117 sets). The latter was a hook and line system in which the gear was dropped to the seafloor untethered to the fishing vessel, and floated to the surface, with the catch, when detachable weights were automatically released. Sablefish dominated longline catches in depths of 200-600fm (334-1,098m), while Pacific grenadier was most abundant between 600 and 1,OOOfm (1,098-1,830m). Best trawl catches of Pacific grenadier were made at depths between 615 and 675fm (1,125 and 1,235 m) and at 760fm (1,391 m). Ripe females were absent from our samples, but spent females were found during the entire year with highest numbers in the spring and early summer. Only one larva was found despite extensive sampling with plankton nets. Pacific grenadier was found to have good edible qualities by a taste-test panel, although the protein content (15 percent) and flesh yield (24 percent) were significantly lower than those of other fishes. A second species, the giant grenadier, Albatrossia pectoralis, was found to have exceptionally poor eating qualities and even lower protein content.

Dinâmica populacional e caracterização conquiliomorfológica de Diplodon ellipticus Spix in Wagner, 1827 (Bivalvia: Unionoida: Hyriidae) da lagoa dos Caiçaras (Piraí, Rio de Janeiro, Brasil)

No presente estudo monitoramos uma população de Diplodon ellipticus Spix in Wagner, 1827 da lagoa dos Caiçaras, Piraí, Rio de Janeiro, e avaliamos alguns aspectos conquiliomorfológicos da larva e do adulto, a relação peso-comprimento, os padrões populacionais tais como crescimento, mortalidade e expectativa de vida, e o ciclo larval. Amostragens mensais foram realizadas de novembro/2012 a novembro/2013 em três pontos da lagoa. Em cada ponto, definimos uma area de 15 m2, que foi subdividida em 15 quadrados de 1m2 cada. Os bivalves foram procurados por três coletores, usando mãos e pés, totalizando 45 minutos de coleta/área. Posteriormente, foram medidos com um paquímetro em relação ao comprimento total, marcados e devolvidos a lagoa. Quinze bivalves foram coletados e analisados em laboratório durante dois anos. Os fatores abióticos (condutividade, temperatura da água, temperatura do ambiente, umidade, pH e oxigênio dissolvido) foram mensurados e amostragens do sedimento e da água foram realizados em cada ponto. Os indivíduos foram agrupados em classes de comprimento com intervalo de 2,0 mm para análise da estrutura de comprimento da população. Os parâmetros de curva de crescimento foram estimados pela rotina ELEFAN (distribuição de frequência) e pelo método de Gulland-Holt (marcação e recaptura), ambos no programa FISAT. A mortalidade foi calculada pelo método da curva de captura convertida em comprimento e a expectativa de vida foi calculada pela equação invertida de von Bertalanffy. Ao todo, 3474 bivalves foram marcados e 1849 recapturados, alguns deles mais de uma vez. O menor bivalve recapturado mediu 23,58 mm e foi recapturado 127 dias depois com 25,50 mm e o maior bivalve recapturado mediu 62,14 mm e foi recapturado 31 dias depois com 62,20 mm. Pelo método indireto analizamos 6922 bivalves com comprimentos variando de 11,37 a 62,49 mm. A maior frequência de comprimento foi encontrada em tamanhos intermediários de 44-46 mm, como foi observado em outras populações de Diplodon. A análise do crescimento, mortalidade e expectativa de vida foram similares em ambos os métodos, por isso, utilizamos em conjunto para ajustar a curva de crescimento da população. A relação peso-comprimento foi alta (r = 0,7-0,8). A avaliação do ciclo reprodutivo indica uma continuidade no desenvolvimento larval ao longo dos meses, à exceção de janeiro/2014. Contabilizamos um total de 54.617 gloquídios, havendo mais indivíduos grávidos com gloquídios (n=5) nos meses de julho e setembro de 2014. Padrão similar foi encontrado em outras espécies de bivalves de água doce, inclusive em Diplodon ellipticus no estado do Paraná. Os gloquídios maduros foram encontrados em amplitudes de temperaturas de 20,1-25,27C e acreditamos que a temperatura pode influenciar na liberação dos mesmos. Os bivalves com o maior e o menor número de gloquídios foram encontrados em novembro/2013 (n= 4759) e setembro/2014 (n= 212), respectivamente. A correlação entre o comprimento do marsúpio e o tamanho da ninhada foi testada pela primeira vez nesse gênero e foi significativa (r= 0,303 , p<0,05). As informações deste estudo são relevantes ao conhecimento da espécie e às futuras ações de gestão que tenham como objetivo preservar as espécies de Diplodon

Desenvolvimento de um instrumento de avaliação da vulnerabilidade de pacientes imunodeprimidos a infecções zoonóticas a partir de animais de estimação.

Os animais de estimação podem ser fonte de infecções, principalmente para seres humanos imunocomprometidos, em especial, pacientes portadores do vírus HIV. Considerando que o contato com animais pode prover benefícios emocionais, profissionais da área da saúde, em particular médicos e médicos veterinários, devem estar conscientes do papel potencial destes animais na transmissão de doenças de forma a preconizar medidas profiláticas para que esta transmissão não ocorra. As circunstâncias que favorecem a transmissão de doenças a partir dos animais de estimação ainda não são totalmente conhecidas, principalmente na realidade brasileira. Faltam estudos com o objetivo de investigar o risco de doenças de origem zoonótica decorrentes do contato com estes animais, hoje também chamados de animais pet. Ademais, ressente-se da falta de um instrumento devidamente elaborado e validado com a finalidade de captar as informações necessárias para a realização de estudos deste tipo ou mesmo para servir como ferramenta de rastreio de situações de vulnerabilidade de pacientes imunodeprimidos com vistas ao aconselhamento sobre medidas de prevenção. Desta maneira, o objetivo deste estudo é elaborar um instrumento para averiguar a vulnerabilidade de pacientes imunodeprimidos a infecções zoonóticas a partir de animais de estimação. Inicialmente, foram mapeados os animais de estimação mais encontrados no ambiente doméstico e as principais infecções que podem ser transmitidas a partir deles. Selecionaram-se, então, os possíveis mecanismos de transmissão a serem abordados. Dentre as espécies de animais de estimação elencadas, os cães, gatos, aves, répteis e os pequenos roedores foram os selecionados para a confecção deste instrumento. As infecções selecionadas foram: Salmonelose; Criptosporidíase; Giardíase; Dermatofitoses, Esporotricose, Bartonelose; Ancilostomíase; Toxocaríase; Psitacose; Toxoplasmose; Escabiose; Campilobacteriose; Criptococose e Histoplasmose. Considerando as diferentes formas de transmissão de cada infecção foram identificados os possíveis atos e comportamentos no contato com animais de estimação, bem como características destes animais, que poderiam aumentar a probabilidade de transmissão. O instrumento desenvolvido foi composto de uma primeira parte abarcando os critérios de elegibilidade, e de outra envolvendo o escopo principal do instrumento. Como as características de contato e as infecções variam de acordo com a espécie de animal, o instrumento abordou cada um dos cinco grupos de animais separadamente. O instrumento aqui proposto concerne à etapa inicial de um processo de desenvolvimento formal para utilização em futuras pesquisas sobre o papel dos animais de estimação na transmissão de infecções para pacientes imunodeprimidos. Estudos que explorem a confiabilidade e validade do instrumento proposto, assim como sua aceitabilidade, são necessários antes que seu uso seja recomendado.

Report on two types of leptocephalus-eel from Vellar Estuary (Bay of Bengal)

Two types of leptocephalus-eel, identified as ophichthyid larva and Muraenesox cinereus, collected from the Vellar estuary, India, are described. M. cinereus larvae are common in the estuary during November-January whereas ophichthyid larvae are very rare, collected on one occasion (January) only.

Induced breeding, embryonic and larval development in Heteropneustes fossilis (Bloch) in the agro-climatic conditions of Maharashtra

Heteropneustes fossilis was induced bred for the first time in the agro-climatic conditions of Maharashtra, India. The embryonic development was completed within 16-18h after fertilisation. Head and tail ends were distinguishable after 3h and 11-12 somites were visible after 6-7h. The eggs started hatching after 14h of incubation. Average hatching time was 16-18h at 26 degrees C. In first day old pro-larva, notochord was deflected upwards, eyes were darkly pigmented and alimentary canal appeared. In fourth day old post-larva intestinal coiling could be seen and yolk was absorbed. Aerial respiration started by 8th day. The 10 day old post-larva was free swimming and fed voraciously attaining a length of 20 mm in 30 days.

Larval ontogeny of a percichthyid fish, Synagrops philippinensis (Günther) in Kagoshima Bay, southern Japan

The larval ontogeny of a developmental series (1.2-8.3mm body length, BL) of Synagrops philippinensis from Kagoshima Bay, southern Japan is described and illustrated. The yolk was completely absorbed in larva of ≥1.5 mm BL. Notochord flexion commenced at about 3.5mm BL and was completed by about 4.0-4.5mm BL. S. philippinensis larvae were distinguished from their congeners based on melanophore patterns, head spination and fin spines and rays. Larvae of 7.5-8.3 mm BL were characterized by anteriorly serrated pelvic spine, two anal spines, nine inner preopercular spines and no melanophore on lateral side of the caudal peduncle; 7.0 to 7.5mm BL larvae by the above characters except serration on pelvic spine; and yolk-sac, pre-flexion, flexing and post-flexion larvae up to 7.0mm BL by unique melanophores on lower lobe of pectoral finfold/fin.

Effect of stocking density on growth of tiger shrimp (Penaeus monodon Fab.) fed on commercial formulated diets

Three different stocking rates in a semi-intensive pilot shrimp project was adopted in duplicates of three treatments designated as T1, T2 and T3 having initial per meter square stocking density of shrimp of 40, 44 and 51 respectively of 0.025g size post larva. The study was conducted for 84 days. Commercial pelleted diets designated as starter - 1, 2, 3 and grower were fed at a satiation level during the study period with a feeding frequency of 4 to 5 times per day. Feed rationing was based on the survivability, body weight and tray checking. 5-25% of the pond water was exchanged daily. Sampling was done for growth after every 2nd week. Monthly sampling was done for mortality in the ponds. Mean weight gain of the shrimp in treatments T1, T2 and T3 were 16.96 ± 1.14, 16.04 ± 1.38 and 14.08 ± 1.17g respectively and T1 with a low stocking density showed a significantly best growth among the treatments. Total mortality in treatments T1, T2 and T3 were as 30.00, 39.77 and 31.37% respectively. Significantly higher feed conversion ratio (FCR) of 1.87 was obtained with shrimp in treatment T3 followed by shrimp in T1 and T2 with FCR values of 1.70 and 1.41 respectively. A positive correlation of growth and salinity was observed during the study. Total production per unit area was the highest in the treatment T3 (4928 kg/ha) and followed by T1 (4747 kg/ha) and T2 (4251 kg/ha). The result show significantly negative correlation between individual growth and density.

Colossal loss of shell and fin-fish larvae during collection of Penaeus monodon (Fab.) fry in the rivers of Satkhira

This study was conducted in five river-estuaries of Satkhira from January to December '96. It was found that during the collection of each Peneaus monodon) post larva (PL), about 45 larvae of other shrimps, 12 individuals of fin-fishes and 530 macro-zooplankters were mercilessly destroyed. It was also recorded that about 11.6 million of P. monodon PLs were harvested annually from the study area. The sh1dy implies that colossal loss of shell and fin-fishes and other plankton resources is done by tiger shrimp fry collectors, and such massive destruction adversely affect the natural productivity and ecological balance of the coastal environment.

Effect of submerged aquatic vegetation on growth and survival of Penaeus monodon (Fab.)

An experiment was conducted in brackish water ponds with transplanted aquatic weed (Najas sp.) to study the effect of submerged aquatic vegetation on culture of Penaeus monodon. Out of six ponds three were without any aquatic vegetation (T1) while in other three ponds weeds were planted covering 40% of the pond bottom (T2). Hatchery produced post larva of P. monodon (0.006 g) were stocked in all ponds at a density of 40,000/ha. Shrimps were fed twice daily with commercial and formulated feed prepared from locally available ingredients. After 105 days of rearing shrimp of highest average weight (63.18g) was obtained from T2 with a survival rate of 25.90% and the total production was obtained at 654.54 kg/ha. The average weight, survival and total production of shrimp in T1 were 35.0 g, 28.76% and 405.63 kg/ha, respectively.

Changes of enzymatic activity during larval development of carp, Catla catla (Ham.)

Quantitative assays of trypsin, amylase and alkaline phosphatases were made in relation to age and food during the larval development of the Indian major carp Catla catla. The responses of all the test enzymes to age and food were identical. No enzymes were detected from the fertilized eggs. Detectable amount of enzymes were first observed in the first day old hatchlings. All the test enzymes in the group fed normal feed tended to rise gradually with advancement of age till day 22 after which an asymptotic level was attained. Absence of food throughout the rearing period caused the enzymatic activity of the larva to remain at the lowest level throughout. When starvation was followed by feeding, enzymatic activity in the former group was consistently higher than that of latter, suggesting that feeding activity was primarily responsible in maintaining the enzymatic activity of carp larva. The enzymatic activity of zooplankton was significantly higher than carp larva till day 6 to 12 after which the latter exceeded the former implying that carp larva during development utilizes the exogenous enzymes of zooplankton.

Artificial insemination in penaeid shrimps

Artificial Insemination (AI) is a tool for genetic manipulation in the shrimp stocks. It is seen as one of the means for propagating shrimp culture to new areas by controlled reproduction. Attempts at artificial insemination in the dominant closed-thelycum penaeid shrimps species of the area viz. Metapenaeus affinis and Metapenaeus brevicornis were induced in wild adult stocks collected off Mumbai coast. Female specimens were subjected to unilateral eyestalk ablation by pinching so as to induce moulting and maturation. AI was performed two days after moulting on these females when the cuticle was still soft and flexible. Moulting also ensured rejection of initial spermatophores, if present. Response of males to electrical stimulation for spermatophore expulsion was spontaneous. Use of tissue glue for spermatophore retention was found to be unnecessary. Latency period ranged between10-16 days, while spawning occurred within 10-12 days of spermatophore transfer. Three partial spawning were recorded viz., two in Metapenaeus affinis and one in Metapenaeus brevicornis with an average spawning and hatching rates of 30% and 72.3% respectively. Average survival from first nauplius (N1) to one-day old post-larva (PLI) was a meager 3.43%. Use of AI in genetic manipulation of shrimp stocks for aquacultural purposes is indicated.

On the spawning activities of kingfish, Scomberomorous commerson, in Oman waters

The spawning activities of kingfish, Scomberomorus commerson, in Oman waters are traced out for the first time. The possible spawning period and spawning ground are identified on the basis of collection of its eggs and larvae from Oman waters. The eggs and early larval characteristics are described suitably with photographic illustration of 4.9 mm larva. The optimum surface water temperature and salinity recorded for the occurrence of kingfish eggs and larvae are 23.57-26.05°C and 36.0-36.1‰, respectively.

Larval rearing of a freshwater prawn Macrobrachium gangeticum

Observations were made on the larval development of a freshwater prawn, Macrobrachium gangeticum, which revealed that hatching occurred in freshwater but the larvae failed to survive after 2nd molting. Salinity was necessary for survival of the larvae after 2nd molting. The complete larval development involved nine larval stages and the 10th stage was considered to be the post-larva which measured between 4.5 and 5.0 mm in length. All the larval stages were completed within 26 days of hatching. Specimens from each larval stage were taken out and examined under a microscope.

Embryonic and larval development of Mystus gulio (Ham.)

Mystus gulio eggs are strongly adhesive and contain relatively small yolk (0.75-1.0 mm). The egg envelop is thick and transparent. First cleavage (two cells), four cells, eight cells, sixteen cells and multi cells stages were found 20, 25, 35-40, 60 and 70 minutes after fertilization, respectively. The morula stage was visualized within 1.5 h after fertilization. The heart beat visible and the circulatory system commenced after 16 h of fertilization. Embryos hatched 18-20h after activation of egg. The newly hatched larva measured 2.82±0.03 mm in length and 0.32±0.06 mg in weight. The yolk sac was fully absorbed by the third day though larvae commenced exogenous feeding even before completion of yolk absorption. A 5-day old post larva began wandering in search of food. Ten-day old post larvae endowed with eight branched rays in dorsal fin and seven in caudal fin. Fifteen-day old post larvae had the pectm:al spine become stout though the embryonic fin folds had to be disappeared. The length of fingerlings ranged from 25-30 mm after 30 days, and their external features were just like those of an adult except that they were not sexually matured.