Ichthyoplankton distribution and abundance in the northern Todos os Santos and Camamu Bays, Bahia State - Brazil

O ictioplâncton coletado ao norte da baía de Todos os Santos e na baía de Camamu (Inverno 2003, Verão 2003, Inverno 2004 e Verão 2005) é analisado de forma comparativa. As amostras foram obtidas com redes de plâncton do tipo cônica-cilíndrica de 200 µm de malhagem, em arrastos horizontais de subsuperfície. Os resultados sobre a distribuição e abundância de ovos de peixes sugerem uma ampla variação sazonal e anual da desova. Entre os verões as diferenças foram especialmente visíveis, sendo observados no primeiro verão (dez/03) os maiores valores quantitativos do projeto (máximo = 106,56 ovos.m-3; média = 43,46 ovos.m-3), enquanto que no segundo verão (jan/05) os valores foram em geral baixos (média geral = 3,49 ovos.m-3). A composição taxonômica é caracterizada pela predominância de gobiídeos, com pequenas variações entre o verão e o inverno. Considerando-se todas as campanhas e as duas áreas, foram identificadas larvas de 11 famílias: Engraulidae, Clupeidae, Mugilidae, Atherinopsidae, Hemiramphidae, Syngnathidae, Blenniidae, Carangidae, Gobiidae, Achiridae e Tetraodontidae.The occurrence, distribution and abundance of ichthyoplankton in Todos os Santos and Camamu Bays were analyzed based on four samplings (winter 2003, summer 2003, winter 2004 and summer 2005). Samples were obtained by surface horizontal hauls, using a 200-µm mesh conical-cylinder plankton net. The distribution and abundance of eggs indicate a remarkable seasonal and annual variation of spawning activity in the region, especially when the two summer campaigns are compared. In summer 2003 the highest quantitative values were recorded, especially for Camamu, where the maximum reached 106.56 eggs.m-3, with an overall average of 43.46 eggs.m-3 for the two areas. In summer 2005 values were relatively low, the overall average being 3.49 eggs.m-3. The larval taxonomic composition is characterized by the predominance of gobiids, with small variation from summer to winter. Considering all the campaigns and samplings undertaken in both areas, larvae of 11 families were identified: Engraulidae, Clupeidae, Mugilidae, Atherinopsidae, Hemiramphidae, Syngnathidae, Blenniidae, Carangidae, Gobiidae, Achiridae and Tetraodontidae

Early development of fat snook, Centropomus parallelus (Poey 1860) (Teleostei, entropomidae) from Southeastern Brazil

Early development of fat snook, Centropomus parallelus (Poey 1860), is described based on embryos and larvae obtained from rearing experiments and from specimens caught in the field, in Cananéia, southeastern Brazil, during December 1999–January 2000. Larvae of common snook, C. undecimalis, were also collected to compare the pigmentation pattern and body shape. Eggs of C. parallelus were relatively small (0.65 to 0.70 mm in diameter), spherical, and usually with a single oil globule. Notochord length (NL) of newly hatched ranged between 1.1 mm to 1.4 mm. Notochord flexion began at 3.4 mm NL and was usually completed by 4.0 mm SL. Larval and early juvenile of both species were very similar with tenuous distinction, however, some morphological and pigmentation characters were used to distinguish their early stages. The main differences were as follow: trend of lower values of the ratio of body depth to body length (BD/BL) for C. par-allelus larger than 10.0 mm SL; absence of the post-temporal spine in C. undecimalis; absence of pigmentation along the dorsal midline of C. parallelus larvae by 2.6–7.0 mm; and presence of a pair of dendritic melanophores posterior to the bases of pelvic fins in C. parallelus larger than 6.0. Key words: Centropomus parallelus, Fish eggs, Fish larvae, Cananéia-Iguape estuarine system, southeastern Brazi

Descripción de larbas y juveniles de Bairdiella Ronchus (Sciaenidae: Teleostei) en el sudeste de Brasil

Developmental stages from flexion larvae to early juvenile of Bairdiella ronchus were described and illustrated from specimens collected along the margins of tidal creeks in the southern zone of the Cananéia-Iguape System on the southeastern coast of Brazil. The B. ronchus larvae were identified working backwards from the juvenile using characteristics common to successively earlier ontogenetic stages. The number of myomeres was 25 (11+14). The flexion of notochord was completed by 5.5 mm SL. The fin formation began in the following sequence: caudal, second dorsal and anal, pelvic fins, first dorsal and pectoral. It was fully completed in this sequence: principal caudal, second dorsal, anal, first dorsal, pelvic and pectoral fins. Squamation began between 10.0 mm SL and 11.1 mm SL, and was entirely completed by 35.0 mm SL. The major head spines included the posterior preocular, supraocular and post-temporal. The larval morphology and pigmentation, mainly the swath pigmentation pattern, were very similar to those described for B. chrysoura in the South Atlantic Bight of the United States. Among sciaenid larvae co-occurring in the study area, Stellifer rastrifer shows larval characteristics more similar to those of B. ronchus, mainly in the preflexion and flexion stages, and in the contraction of the swath pigmentation. They can be differentiated by the fact that in S. rastrifer there is a post-anal lateral pigmentation or caudal pigment on the ventral midline radiating dorsally, which is absent in B. ronchus.El desarrollo larvario de Bairdiella ronchus desde estadios de flexión hasta juvenil temprano de fueron descritos e ilustrados a partir de especimenes recogidos a lo largo de los canales de marea de la parte sur del Sistema de Cananéia-Iguape en la costa sudeste de Brasil. Las larvas de B. ronchus fueron identificadas a partir de los juveniles usando características comunes a sucesivos estadios tempranos ontogenéticos. El número de miómeros es de 25 (11+14). La flexión de la notocorda se completa a los 5.5 mm SL. La formación de las aletas se inicia según la siguiente secuencia: caudal, segunda dorsal, anal, pélvicas, primera dorsal y pectoral, y alcanza la dotación final en este orden: caudal principal, segunda dorsal, anal, primera dorsal, pélvicas y pectoral. La escamación comienza entre 10.0 mm SL y 11.1 mm SL, y se completa a los 35.0 mm SL. Las principales espinas de la cabeza incluyen las preoculares anterior y posterior, supraocular y pos-temporal. La morfología y pigmentación larvaria, principalmente el patrón de pigmentación “swath”, fue muy similar al descrito para B. chrysoura del “South Atlantic Bight” de Estados Unidos. Entre las larvas sciaenidos encontradas también en el área de estudio, Stellifer rastrifer es la que muestra características más similares a B. ronchus, principalmente en los estadios de preflexión y flexión, y por la contracción de la pigmentación “swath”. Las larvas de S. rastrifer pueden ser identificadas por la presencia de una pigmentación pos-anal lateral o pigmentos caudales en la línea central ventral que radian dorsalmente, ausentes en B. ronchus

Ichthyoplankton distribution and abundance in the northern Todos os Santos and Camamu Bays, Bahia State - Brazil

The occurrence, distribution and abundance of ichthyoplankton in Todos os Santos and Camamu Bays were analyzed based on four samplings (winter 2003, summer 2003, winter 2004 and summer 2005). Samples were obtained by surface horizontal hauls, using a 200-µm mesh conical-cylinder plankton net. The distribution and abundance of eggs indicate a remarkable seasonal and annual variation of spawning activity in the region, especially when the two summer campaigns are compared. In summer 2003 the highest quantitative values were recorded, especially for Camamu, where the maximum reached 106.56 eggs.m-3, with an overall average of 43.46 eggs.m-3 for the two areas. In summer 2005 values were relatively low, the overall average being 3.49 eggs.m-3. The larval taxonomic composition is characterized by the predominance of gobiids, with small variation from summer to winter. Considering all the campaigns and samplings undertaken in both areas, larvae of 11 families were identified: Engraulidae, Clupeidae, Mugilidae, Atherinopsidae, Hemiramphidae, Syngnathidae, Blenniidae, Carangidae, Gobiidae, Achiridae and Tetraodontidae.<br>O ictioplâncton coletado ao norte da baía de Todos os Santos e na baía de Camamu (Inverno 2003, Verão 2003, Inverno 2004 e Verão 2005) é analisado de forma comparativa. As amostras foram obtidas com redes de plâncton do tipo cônica-cilíndrica de 200 µm de malhagem, em arrastos horizontais de subsuperfície. Os resultados sobre a distribuição e abundância de ovos de peixes sugerem uma ampla variação sazonal e anual da desova. Entre os verões as diferenças foram especialmente visíveis, sendo observados no primeiro verão (dez/03) os maiores valores quantitativos do projeto (máximo = 106,56 ovos.m-3; média = 43,46 ovos.m-3), enquanto que no segundo verão (jan/05) os valores foram em geral baixos (média geral = 3,49 ovos.m-3). A composição taxonômica é caracterizada pela predominância de gobiídeos, com pequenas variações entre o verão e o inverno. Considerando-se todas as campanhas e as duas áreas, foram identificadas larvas de 11 famílias: Engraulidae, Clupeidae, Mugilidae, Atherinopsidae, Hemiramphidae, Syngnathidae, Blenniidae, Carangidae, Gobiidae, Achiridae e Tetraodontidae

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0-4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2-6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates