Developmental Social Experience Changes Behavior in a Threatening Environment in Corydoras Catfish.

Coordinated responses to threats are important for predator evasion in many species. This study examines the effect of developmental social experience on antipredator behavior and group cohesion in a highly gregarious catfish that communicates via tactile interaction, Corydoras aeneus. We reared fish either in a mixed-age group of age-matched peers and adult C. aeneus (mixed-age condition, or MAC), or with age-matched peers only (same-age condition, or SAC). A startle test was conducted with small groups of subadults from either social rearing condition. Prior to any startle events, SAC subadults had increased tactile communication compared to MAC subadults, but SAC individuals were overall less active. SAC fish exhibited a stronger antipredator response to startles, and were more likely to freeze or take refuge in cover in response to a startle than MAC fish. MAC fish tended to respond to startle events by maintaining or decreasing their cohesion, whereas SAC fish tended to maintain or increase their cohesion. These behavioral differences are attributed to MAC fish developing with group protection as a result of shoaling with adults, resulting in reduced antipredator responses when reared with adults. This study underscores how social context during development can be critical in shaping how individuals perceive and respond to potential threats in their environment.

Comprehensive Husbandry Protocol for Corydoras Catfish and Many Other Amazonian Species.

A variety of fish species have proven instrumental in the investigation of evolution, behavior, ecology, and physiology, among many other fields. Many model systems (e.g., zebrafish, guppies, and three-spined sticklebacks) have been maintained by institutions and have had protocols written with respect to their husbandry. Here we present the protocols we have developed to maintain and breed a variety of Corydoras catfish species, which are native to the tropical Americas. Corydoras species are excellent systems for investigating behavior, ecology, and other topics, and our husbandry protocols would be suitable for nearly every species in the genus. In addition, these protocols are appropriate for a variety of softwater Amazonian species, and we present options for a variety of housing and husbandry conditions. On the whole, we suggest that, in a scientific laboratory setting, the use of remineralized reverse osmosis water is most appropriate and that in context, a single measure, total dissolved solids, can be used to monitor the water chemistry for water introduced to fish enclosures.

Familiarity, personality, and foraging performance in three-spined sticklebacks.

Animals can gain large benefits from living in groups but must coordinate with their groupmates in order to do so. Social interactions between groupmates drive overall group coordination and are influenced by the characteristics of individual group members. In particular, consistent inter-individual differences in behaviour (e.g. boldness) and familiarity between individuals in groups profoundly affect the individual interactions that mediate group coordination. However, the effects of boldness and familiarity have mostly been studied in isolation. Here we describe how familiarity and boldness interact to affect individual performance, leadership, and group coordination in small shoals of three-spined sticklebacks (Gasterosteus aculeatus) solving a novel foraging task. Groups of higher average boldness were less cohesive, but only when group members were familiar with one another. Familiarity affected shy and bold individuals' foraging performance and leadership tendencies differently depending on group characteristics: the shyest group member experienced declining foraging success and leadership with increased group boldness in familiar groups, but experienced the opposite effect on foraging and no effect on leadership in unfamiliar groups. The boldest group member, in contrast, exhibited the opposite pattern: leading and eating more with increasing group boldness in familiar groups, but eating less with increasing group boldness in unfamiliar groups. These results suggest that both boldness and familiarity are important for establishing group behaviour and coordination, and that consistent inter-individual differences in behaviour may primarily impact group coordination once familiarity has been established.

Inferior vena cava ultrasonography before general anesthesia cannot predict arterial hypotension in patients undergoing vascular surgery.

INTRODUCTION: Intraoperative hypotension (IH) is an independent predictor of mortality. Some experts have suggested that ultrasound measurement of the inferior vena cava (IVC) in spontaneous ventilation can predict IH. OBJECTIVE: To evaluate the capacity of ultrasound measures of IVC in spontaneous ventilation to predict episodes of IH after anaesthesia induction. PATIENTS AND METHODS: We studied 55 high-risk cardiac patients undergoing vascular surgery. The maximum (dIVCmax) and minimum (dIVCmin) diameter of the IVC were measured and the collapsibility index CI = (dIVCmax-dIVCmin)/dIVCmax was calculated prior to anaesthesia induction. Three definitions of IH were used: systolic blood pressure (SBP) less than 100 mmHg, mean arterial pressure (MAP) less than 60 mmHg, and a decrease in MAP greater than or equal to 30% compared to baseline. RESULTS: There were no significant differences in dIVCmax or in CI between patients presenting IH after anaesthesia induction and those who did not. ROC curves for dIVCmax showed an area under the curve of 0.55 (0.39-0.70), 0.69 (0.48-0.90), and 0.57 (0.42-0.73) and ROC curves for the CI were 0.62 (0.47-0.78), 0.60 (0.41-0.78) and 0.62 (0.47-0.78) for the 3 definitions of IH (<100 mmHg, MAP < 60 mmHg, and MAP ≥30% baseline), respectively. CONCLUSIONS: Ultrasound measurements of IVC in spontaneous ventilation are not good predictors of IH after anaesthesia induction in these patients. The optimal cut-off points show low specificity and moderate sensitivity for predicting IH.

Identification of slit3 as a locus affecting nicotine preference in zebrafish and human smoking behaviour.

To facilitate smoking genetics research we determined whether a screen of mutagenized zebrafish for nicotine preference could predict loci affecting smoking behaviour. From 30 screened F3 sibling groups, where each was derived from an individual ethyl-nitrosurea mutagenized F0 fish, two showed increased or decreased nicotine preference. Out of 25 inactivating mutations carried by the F3 fish, one in the slit3 gene segregated with increased nicotine preference in heterozygous individuals. Focussed SNP analysis of the human SLIT3 locus in cohorts from UK (n=863) and Finland (n=1715) identified two variants associated with cigarette consumption and likelihood of cessation. Characterisation of slit3 mutant larvae and adult fish revealed decreased sensitivity to the dopaminergic and serotonergic antagonist amisulpride, known to affect startle reflex that is correlated with addiction in humans, and increased htr1aa mRNA expression in mutant larvae. No effect on neuronal pathfinding was detected. These findings reveal a role for SLIT3 in development of pathways affecting responses to nicotine in zebrafish and smoking in humans.

Desensitizing Toothpastes for Dentin Hypersensitivity: A Network Meta-analysis.

The goal of this systematic review and network meta-analysis was to compare the relative effects of toothpaste formulations for dentin hypersensitivity (DH), tested in randomized controlled trials (RCTs). We searched 7 databases to February 2019. Paired reviewers independently screened studies, extracted data, and performed risk of bias assessment. The outcome of interest was painful response measured through tactile, cold, and air stimuli. We conducted a random-effects Bayesian network meta-analysis using standardized mean difference (SMD) and their credible intervals (CIs) as the measure of effect for each pain stimuli. We assessed certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We included 125 RCTs (12,541 patients). For tactile stimulus, the following active ingredients showed large beneficial effects compared to fluoride with moderate certainty of evidence (SMD; 95% CI): potassium + stannous fluoride (SnF2) (3.05; 1.69-4.41), calcium sodium phosphosilicate (CSP) (2.14; 0.75-3.53), SnF2 (2.02; 1.06-2.99), potassium + hydroxyapatite (2.47; 0.3-4.64), strontium (1.43; 0.46-2.41), and potassium (1.23; 0.48-1.98). For cold stimulus, CSP showed large beneficial effects compared to fluoride (3.93; 0.34-7.53) with moderate certainty; for air stimulus, arginine (2.22; 1.45-2.99), potassium + hydroxyapatite (2.44; 0.33-4.55), potassium + SnF2 (2.28; 0.87-3.69), CSP (1.98; 0.99-2.98), and SnF2 (1.9; 1.03-2.77) showed large beneficial effects compared to fluoride with moderate to high certainty. Most toothpaste formulations showed evidence of superiority against placebo or fluorides (amine fluoride, sodium monofluorophosphate, or sodium fluoride). CSP was most beneficial for all 3 stimuli with high to moderate certainty. SnF2 alone and potassium combined with SnF2 or hydroxyapatite were beneficial for tactile and air stimulus with high to moderate certainty. Arginine was beneficial for air stimulus, and strontium and potassium were beneficial for tactile stimulus, with moderate certainty.

Coping with strangers: how familiarity and active interactions shape group coordination in Corydoras aeneus.

Social groups composed of familiar individuals exhibit better coordination than unfamiliar groups; however, the ways familiarity contributes to coordination are poorly understood. Prior social experience probably allows individuals to learn the tendencies of familiar group-mates and respond accordingly. Without prior experience, individuals would benefit from strategies for enhancing coordination with unfamiliar others. We used a social catfish, Corydoras aeneus, that uses discrete, observable tactile interactions to assess whether active interactions could facilitate coordination, and how their role might be mediated by familiarity. We describe this previously understudied physical interaction, 'nudges', and show it to be associated with group coordination and cohesion. Furthermore, we investigated nudging and coordination in familiar/unfamiliar pairs. In all pairs, we found that nudging rates were higher during coordinated movements than when fish were together but not coordinating. We observed no familiarity-based difference in coordination or cohesion. Instead, unfamiliar pairs exhibited significantly higher nudging rates, suggesting that unfamiliar pairs may be able to compensate for unfamiliarity through increased nudging. By contrast, familiar individuals coordinated with comparatively little nudging. Second, we analysed nudging and cohesion within triplets of two familiar and one unfamiliar individual (where familiar individuals had a choice of partner). Although all individuals nudged at similar rates, the unfamiliar group-mate was less cohesive than its familiar group-mates and spent more time alone. Unfamiliar individuals that nudged their group-mates more frequently exhibited higher cohesion, indicating that nudging may facilitate cohesion for the unfamiliar group-mate. Overall, our results suggest that nudges can mitigate unfamiliarity, but that their usage is reduced in the case of familiar individuals, implying a cost is associated with the behaviour.

Anti-ApoA-I IgG antibodies are not associated with carotid artery disease progression and first-time cardiovascular events in middle-aged individuals.

OBJECTIVE: IgG antibodies against apolipoprotein A-I (ApoA-I) have been found to be elevated in subjects from the general population with clinically manifest cardiovascular disease and in myocardial infarction patients with an adverse prognosis. Here, we investigated whether these antibodies are prospectively associated with carotid artery disease progression and with the risk for first-time cardiovascular events in individuals with no previous history of cardiovascular disease. APPROACH AND RESULTS: We selected 383 subjects from the cardiovascular cohort of Malmö Diet and Cancer study who suffered a coronary event during a median follow-up period of 15.4 (10.3-16.4) years and 395 age- and sex-matched controls. None of the study participants had a previous history of coronary artery disease or stroke. Anti-ApoA-I IgG were measured by ELISA in serum samples collected at baseline. Intima-media thickness (IMT) was measured in the common carotid artery and in the carotid bifurcation at baseline and after 15.9 (±1.5) years. We found no associations between anti-ApoA-I IgG and carotid artery IMT at baseline or with IMT progression during follow-up. In Cox proportional hazards analyses adjusted for traditional cardiovascular risk factors, the hazard ratio (HR 95%CI) for the primary outcome, incident coronary events, was 0.97 (0.75-1.25), P = 0.782, in subjects with anti-ApoA-I IgG within the highest tertile compared with the lowest tertile. Similarly, we did not find any associations with the secondary outcome, incident first-time stroke. CONCLUSIONS: Serum autoantibodies against ApoA-I do not correlate with disease progression and adverse events in cardiovascular disease-free individuals from the general population.

Amelanotic iris melanoma in a 7 year-old hispanic boy with subclinical globe perforation. / Melanoma amelanótico del iris en un niño hispano de 7 años con perforación del globo subclínica.

We report an unusual case of an amelanotic melanoma in a 7 year old hispanic child with subclinical globe perforation. Uveal melanoma rarely occurs in children. Young affected patients are mostly light-colored eye Caucasian adolescents. Since they are not common, these tumors are usually not recognized and misdiagnosed. Differential diagnoses and therapeutic options are outlined.

Anestesia regional periférica para revascularización arterial de miembros inferiores. Revisión bibliográfica y casos clínicos / Peripheral regional anesthesia for arterial revascularization of lower limbs. Bibliographical review and clinical cases

Introducción: La tendencia actual es diferir la cirugía de revascularización de miembros inferiores hasta etapas avanzadas, lo que explica que sean pacientes de mayor complejidad con alta morbimortalidad cardíaca y respiratoria. Los mayores avances para reducirlas, se han desarrollado en la preparación de los pacientes y en las técnicas quirúrgicas. La elección de la técnica anestésica no ha sido considerada un factor determinante. Los bloqueos regionales presentan potenciales ventajas, como mayor estabilidad hemodinámica y respiratoria. Objetivo: Realizar una revisión bibliográfica y presentación de casos clínicos sobre la utilidad de los bloqueos periféricos para anestesia en la cirugía de revascularización de miembros inferiores. Material y métodos: La búsqueda se realizó a través de la base de datos Medline, LILACS y SciELO. Se incluyeron estudios donde los bloqueos periféricos se utilizaron para anestesia. Se describen dos casos clínicos. Resultados: Se seleccionaron 4 artículos originales, 3 de ellos eran estudios descriptivos de la técnica y el cuarto una comparación con anestesia general inhalatoria. 2más correspondieron a casos clínicos. Conclusiones: No existe evidencia suficiente que permita concluir que reducen la mortalidad o la morbilidad cuando se la compara con las demás técnicas anestésicas. Esto puede ser debido al diseño metodológico de los estudios, a la no utilización de la ecografía como guía y la no sistematización de los bloqueos. El análisis de los casos clínicos sugiere que en situaciones específicas como pacientes de alto riesgo cardíaco y respiratorio, bajo tratamiento con anticoagulantes y antiagregantes estos presentan ventajas sobre las otras técnicas.

Background: The current trend is to defer revascularization surgery from lower limbs to advanced stages, which explains why they are more complex patients with high cardiac and respiratory mortality. The choice of anesthetic technique remains controversial. Regional blockades have potential advantages, such as hemodynamic and respiratory stability. Our primary objective was a bibliographic review to assess the peripheral blockages for anesthesia in lower limb revascularization surgery. Our secondary objective was report two clinical cases. Material and methods: The search was performed through the Medline, LILACS and SciELO database. We included studies where peripheral blocks were used for anesthesia. Two clinical cases are described. Results: Four original articles were selected, 3 of which were descriptive studies of the technique and the fourth a comparison with general inhalation anesthesia. 2 more corresponded to clinical cases. Conclusions: There is insufficient evidence to conclude that peripheral nerve block reduce mortality or morbidity when compared with other anesthetic techniques. This may be due to the methodological design of the studies, to the non-use of echocardiography as a guide and the non-systematization of the blocks. The analysis of the clinical cases suggests that this technique is a good option in specific situations as patients with high cardiac and respiratory risk, under treatment with anticoagulants and antiplatelets drugs.

Microcirculatory changes during cardiac surgery with cardiopulmonary bypass. / Alteraciones microcirculatorias en cirugía cardíaca con circulación extracorpórea.

OBJECTIVE: To evaluate microcirculation in intermediate and high mortality risk patients undergoing cardiac surgery (CS) with cardiopulmonary bypass (CPB). PATIENTS AND METHODS: The study included 22 patients with a Euroscore >3. Using the Videomicroscopy Side Stream Dark Field system, and evaluation was made of, capillary density, proportion of perfused capillaries, density of perfused capillaries, microcirculatory flow index (MFI), and heterogeneity flow index. Three to five video sequences were recorded: after induction of anaesthesia (T1), at the beginning of the CPB (T2), before finalising CPB (T3), at the end of the surgery, and before the patient was transferred to Intensive Care Unit (T4). Mean arterial pressure decreased, while the blood lactate increased significantly, when comparing the initial and final values (P<.05). MFI increased significantly in T3 and T4 (P<.05) with regards to the initial values. When the patients with and without postoperative complications were compared, significant differences were found in, Euroscore, left ventricular ejection fraction, and MFI in T3. CONCLUSIONS: in patients with intermediate/high preoperative risk, CS and CBP can involve an increase in MFI and blood lactate at the end of the study. These alterations suggest the possibility of a functional microcirculatory shunt at tissue perfusion level, secondary to the surgical injury and the CPB. Further investigation is needed to have a better understanding of the mechanisms involved.

[The changes in the oxygen saturations in the superior vena cava and the pulmonary artery are not the same during cardiac surgery]. / Las tendencias en el tiempo de las saturaciones de oxígeno en la vena cava superior y la arteria pulmonar no son equivalentes en cirugía cardiaca.

OBJECTIVE: To evaluate the changes over time (trend) in sign and magnitude for SSVO2 and SVO2 during and after cardiac surgery. PATIENTS AND METHODS: A prospective and observational study was conducted on 34 cardiac surgery patients. Venous blood samples were taken simultaneously from the introductor (SVCO2) and distal (SVO2) port of the pulmonary artery catheter at predefined intervals. Systemic and pulmonary hemodynamic variables were measured at the same time. The trend was calculated as the difference between 2 consecutive measurements (tSO2). Data were processed with ANOVA for multiple comparisons, Pearson correlation coefficient and Bland-Altman analysis. RESULTS: There was a significant correlation between SVCO2 and tSVO2 (R(2)=0.55), the mean of the differences was 0.36±7.75%, and the limits of agreement ranged from -15.1 to 15.9%. The sign of the trend was similar in 85.1% of the paired data. However, the magnitude of the changes in tSVCO2 and tSVO2 were not always equivalent. Between 0 and 5% of the change in the tSVCO2 was coincident with only 44.7% of the tSVO2. A wide variation was found between both trends when the signs and magnitudes of the changes were taken into account. CONCLUSIONS: When considering the sign and magnitude, the change over time of central venous O2 saturations were not interchangeable in cardiac surgery patients. Clinical decisions based exclusively on tSVCO2 monitoring should be taken with caution.

[Anaestheia for valve replacement in the second trimester of pregnancy]. / Anestesia para sustitución valvular en el segundo trimestre del embarazo.

Cardiac surgery in the pregnant woman gives rise to several anesthetic challenges, as the mother, but mainly the fetus, have a risk of high morbidity and mortality. In this context, the cardiopulmonary bypass is the most complex period, owing to the risks of fetal hypoxia it entails. Due to the absence, for ethical reasons, of prospective trials that provide generally accepted guidelines in intraoperative management, it means that physicians have to work based on case reports in the literature. These procedures also require team coordination to be successful. The case is presented of a 19 weeks pregnant woman, who required a mitral valve replacement, which was achieved with success, and enabled her to complete her pregnancy without complications. Details are provided on the published references on which our management was based.

Estudo fitoquímico e análise mutagênica das folhas e inflorescências de Erythrina mulungu (Mart. ex Benth. ) através do teste de micronúcleo em roedores / Phytochemical and mutagenic analysis of leaves and inflorescences of Erythrina mulungu (Mart. Ex Benth. ) through micronucleus test in rodents

Este trabalho teve como objetivo investigar a composição química, estabelecer a dose letal média (DL50) e avaliar os potenciais efeitos mutagênicos do extrato hidroalcoólico de folhas e inflorescências de Erythrina mulungu Mart. ex Benth por meio do teste de micronúcleo em medula óssea de camundongos. Os ensaios fitoquímicos foram realizados através de reações preliminares com mudança de coloração e/ou formação de precipitado; a DL50, por meio da administração intraperitoneal de três concentrações dos extratos, avaliando-se o número de óbitos após 48 horas e o teste de micronúcleo foi feito por meio do método do esfregaço, após exposição dos animais a cinco dias de tratamento. Os resultados fitoquímicos demonstraram presença de açúcares redutores, fenóis e taninos, proteínas e aminoácidos, flavonóides, alcalóides, depsídeos e depsidonas e derivados de cumarina em ambos os órgãos; saponinas espumídicas e esteróides e triterpenóides nas folhas e glicosídeos cardiotônicos e antraquinônicos e alcalóides nas inflorescências. Para a DL50 a folha demonstrou-se atóxica e a inflorescência moderadamente tóxica. Para o teste de micronúcleo, os resultados indicaram ausência de citotoxicidade e genotoxicidade dose-dependente para as folhas e independente da dose para as inflorescências. Assim, esses resultados sugerem que a planta, nas condições analisadas, possui potencial para induzir danos ao DNA.

This study aimed to investigate the chemical composition, to establish the mean lethal dose (LD50) and to assess the potential mutagenic effects of hydroalcoholic extract of leaves and inflorescences of Erythrina mulungu Mart. ex Benth by using micronucleus test in bone marrow of mice. Phytochemical assays were carried out through preliminary reactions with color change and/or precipitate formation; the LD50 was obtained by intraperitoneal administration of three concentrations of the extracts, assessing the number of deaths after 48 hours, and the micronucleus test was done by the smear method, after exposure of animals to five days of treatment. Phytochemical results showed the presence of reducing sugars, phenols and tannins, proteins and amino acids, flavonoids, alkaloids, depsides, depsidones and coumarin derivatives in both organs; foaming and steroidal saponins and triterpenes in the leaves and cardiotonic and anthraquinonic glycosides and alkaloids in the inflorescences. Considering the LD50, the leaf was atoxic and the inflorescence was moderately toxic. As regards the micronucleus test, results indicated absence of cytotoxicity while genotoxicity was dose-dependent for leaves and dose-independent for inflorescences. Thus, these results suggest that the plant, under the tested conditions, has the potential to induce damages to the DNA.

Contribution of the coronary sinus blood to the pulmonary artery oxygen saturation gradient in cardiac surgery patients.

BACKGROUND: The coronary sinus oxygen saturation (SO2) can affect the oxygen saturation of the superior vena cava (superior cava SO2) and the pulmonary artery (pulmonary artery SO2), causing a gradient between the latter two (ΔSO2), as has been observed in different physiological and pathological conditions. The objective of the study was to evaluate the different determinants of ΔSO2 in cardiac surgery patients. METHODS: An observational, prospective study was carried out on 18 patients undergoing elective cardiac surgery. Blood samples were obtained from the superior vena cava, the pulmonary artery, the inferior vena cava, and the coronary sinus before extracorporeal circulation. RESULTS: The following measurements were made: superior cava SO2, pulmonary artery SO2, coronary sinus SO2, and inferior cava SO2. The mean values (± SD) were as follows: superior cava SO2=76.4±12.6%; inferior cava SO2=72.7±15.8%; coronary sinus SO2=46.6±17.0%; and pulmonary artery SO2=71.9±12.9%. The ΔSO2 was 4.5±5.5%. The average oxygen saturation (SO2avg=[Superior cava SO2 + inferior cava SO2]/2) was 74.6±13.7%. The superior cava SO2 was significantly higher than the pulmonary artery SO2, and the ΔSO2 was significantly different from zero (P≤0.05). No significant differences were found between the superior cava SO2 and the inferior cava SO2, and both were significantly different from the coronary sinus SO2. The difference between SO2avg and the pulmonary artery SO2 was 2.74±4.4%. CONCLUSION: The observed ΔSO2 could only be explained by dilution of the superior cava SO2 with blood with a lower SO2. The coronary sinus blood contributed to generate this gradient.

Evaluation of three methodologies to estimate the VO2max in people of different ages.

Aging and gender are factors that affect the variation of physical work capacity. The present paper highlights the importance of the metabolism used by ergonomics to establish the appropriate limits of loads at work. This study compares the aerobic capacity of people from 20 to 71 years old split in 5 different groups. The laboratory experiment tested 33 volunteers (19 women and 14 men). A submaximal step test was used to measure the VO(2) using a portable breath by breath metabolic system and a telemetric heart rate monitor. Three methods to estimate the VO(2max) were compared: 1) a direct measurement of VO(2), 2) estimation by heart rate, and 3) a step test method using predetermined charts. Significant difference was encountered among the estimation methods as well as among the age ranges (F(2,92)=6.43, p<0.05 y F(4,92)=7.18, p<0.05 respectively). The method of direct measurement and the method of predetermined charts were different for the estimation of the VO(2max) with a confidence level of 95%. The method of predetermined charts is better adapted for males and people younger than 30 years. The estimation through non invasive heart rate apparatus was a good appraiser of the maximal oxygen consumption considering both genders and all the age groups.

Pathogenicity of a ratite-origin influenza A H5 virus in ostriches (Struthio camelus).

Ostriches were inoculated with a highly pathogenic avian influenza (HPAI) virus of ratite origin, A/emu/Texas/39924/93 (H5N2) done clB. The aim of this study was to evaluate the pathogenicity of this isolate for ostriches and to assess the ability of routine virologic and serologic tests to detect infection. Avian influenza virus (AIV) was isolated from tracheal swabs from 2 to 12 days postinfection and from cloacal swabs from 3 to 10 days postinfection. AIV was also isolated from a wide range of tissues. Birds seroconverted as early as 7 days postinfection. This study indicates that HPAI virus of ratite origin replicates extensively in infected ostriches without causing significant clinical disease or mortality.

Characterization of avian influenza virus isolates submitted to the National Centre for Foreign Animal Disease between 1997 and 2001.

The National Centre for Foreign Animal Disease (NCFAD) in Winnipeg, Manitoba, is the Canadian Food Inspection Agency's (CFIA) newest high biocontainment laboratory. One of the functions of the NCFAD is to serve as a national reference laboratory for avian influenza. Between 1997 and 2001, 15 avian influenza virus isolates were characterized. These isolates originated from domestic poultry, imported caged birds held in quarantine, and wild birds. Diagnostic specimens were submitted to the NCFAD by CFIA field veterinarians, provincial veterinary diagnostic laboratories, and veterinary colleges. Characterization of isolates included the determination of H and N subtypes: H1, H6, H7, and H10 subtypes were isolated from domestic poultry; H3, H4, and three H13 viruses were isolated from water fowl, and six H3 viruses were isolated from caged birds being held in import quarantine. Selected isolates were characterized with respect to their pathogenic potential by intravenous inoculation of 4-to-6-wk-old chickens. A molecular-based protocol was used to assess the pathogenicity of one H7 isolate. During this period, work was also carried out toward validating our molecular pathotyping protocol for avian influenza viruses with H5 and H7 hemagglutinin subtypes.

Molecular characterization of avian paramyxovirus 1 isolates collected from cormorants in Canada from 1995 to 2000.

Sequences encompassing cleavage sites of fusion protein genes were obtained for avian paramyxovirus 1 isolates from cormorants in Canada. All isolates have the virulent cleavage site SRGRRQKR*FVG. They form a distinct cluster within isolates obtained around the world and may represent a novel genotype closely related to genotype V.