Neonatal Lung Ultrasound and Surfactant Administration: A Pragmatic, Multicenter Study.

BACKGROUND: Previous research shows that a lung ultrasound score (LUS) can anticipate CPAP failure in neonatal respiratory distress syndrome. RESEARCH QUESTION: Can LUS also predict the need for surfactant replacement? STUDY DESIGN AND METHODS: Multicenter, pragmatic study of preterm neonates who underwent lung ultrasound at birth and those given surfactant by masked physicians, who also were scanned within 24 h from administration. Clinical data and respiratory support variables were recorded. Accuracy of LUS, oxygen saturation to Fio2 ratio, Fio2, and Silverman score for surfactant administration were evaluated using receiver operating characteristic curves. The simultaneous prognostic values of LUS and oxygen saturation to Fio2 ratio for surfactant administration, adjusting for gestational age (GA), were analyzed through a logistic regression model. RESULTS: Two hundred forty infants were enrolled. One hundred eight received at least one dose of surfactant. LUS predicted the first surfactant administration with an area under the receiver operating characteristic curve (AUC) of 0.86 (95% CI, 0.81-0.91), cut off of 9, sensitivity of 0.79 (95% CI, 0.70-0.86), specificity of 0.83 (95% CI, 0.76-0.89), positive predictive value of 0.79 (95% CI, 0.71-0.87), negative predictive value of 0.82 (95% CI, 0.75-0.89), positive likelihood ratio of 4.65 (95% CI, 3.14-6.89), and negative likelihood ratio of 0.26 (95% CI, 0.18-0.37). No significant difference was shown among different GA groups: 25 to 27 weeks' GA (AUC, 0.91; 95% CI, 0.84-0.99), 28 to 30 weeks' GA (AUC, 0.81; 95% CI, 0.72-0.91), and 31 to 33 weeks' GA (AUC, 0.88; 95% CI, 0.79-0.95), respectively. LUS declined significantly within 24 h in infants receiving one surfactant dose. When comparing Fio2, oxygen saturation to Fio2 ratio, LUS, and Silverman scores as criteria for surfactant administration, only the latter showed a significantly poorer performance. The combination of oxygen saturation to Fio2 ratio and LUS showed the highest predictive power, with an AUC of 0.93 (95% CI, 0.89-0.97), regardless of the GA interval. INTERPRETATION: LUS is a reliable criterion to administer the first surfactant dose regardless of GA. Its association with oxygen saturation to Fio2 ratio significantly improves the prediction power for surfactant need.

Lung Ultrasound Score Progress in Neonatal Respiratory Distress Syndrome.

BACKGROUND AND OBJECTIVES: The utility of a lung ultrasound score (LUS) has been described in the early phases of neonatal respiratory distress syndrome (RDS). We investigated lung ultrasound as a tool to monitor respiratory status in preterm neonates throughout the course of RDS. METHODS: Preterm neonates, stratified in 3 gestational age cohorts (25-27, 28-30, and 31-33 weeks), underwent lung ultrasound at weekly intervals from birth. Clinical data, respiratory support variables, and major complications (sepsis, patent ductus arteriosus, pneumothorax, and persistent pulmonary hypertension of the neonate) were also recorded. RESULTS: We enrolled 240 infants in total. The 3 gestational age intervals had significantly different LUS patterns. There was a significant correlation between LUS and the ratio of oxygen saturation to inspired oxygen throughout the admission, increasing with gestational age (b = -0.002 [P < .001] at 25-27 weeks; b = -0.006 [P < .001] at 28-30 weeks; b = -0.012 [P < .001] at 31-33 weeks). Infants with complications had a higher LUS already at birth (12 interquartile range 13-8 vs 8 interquartile range 12-4 control group; P = .001). In infants 25 to 30 weeks' gestation, the LUS at 7 days of life predicted bronchopulmonary dysplasia with an area under the curve of 0.82 (95% confidence interval 0.71 to 93). CONCLUSIONS: In preterm neonates affected by RDS, the LUS trajectory is gestational age dependent, significantly correlates with the oxygenation status, and predicts bronchopulmonary dysplasia. In this population, LUS is a useful, bedside, noninvasive tool to monitor the respiratory status.

Avian haemosporidians in the cattle egret (Bubulcus ibis) from central-western and southern Africa: High diversity and prevalence.

We described the geographic distribution of 82 haemosporidian lineages (Plasmodium, Haemoproteus, and Leucocytozoon) in the cattle egret sampled in five countries in central-western and southern Africa. Seventy-three lineages have not previously been reported. We determined the prevalence of three haemosporidians in the samples. We investigated the influence of the internal environment of the host and environmental variables on the Plasmodium diversity and whether environmental variables may explain spatial variations in the prevalence of Plasmodium. We screened DNA from 509 blood samples from nestlings in 15 African colonies for infection by sequencing the cytochrome b gene of parasites. The molecular phylogenetic analysis was performed using Bayesian methods and including sequences from the MalAvi and GeneBank databases. We found 62 new Plasmodium lineages in a clade with MYCAME02, which is a lineage described in waterbirds and recently identified in birds of prey as Plasmodium paranucleophilum. Two Haemoproteus lineages identified in cattle egret formed a distinct group with Haemoproteus catharti and MYCAMH1 (Haemoproteus spp.). Seven Leucocytozoon lineages found in the cattle egret clustered with Leucocytozoon californicus. We found different Plasmodium diversities among the colonies sampled, demonstrating that the internal environment of the host is not the primary determinant of diversity. A linear mixed-effects multivariate model showed that precipitation was positively associated with Plasmodium diversity when controlling for the effects of temperature, colony composition (mixed and non-mixed species) and country. Moreover, a generalized mixed model showed that temperature was positively associated with the prevalence of Plasmodium when controlling for precipitation, elevation and country. We conclude that the cattle egret is a good model for future haemosporidian studies, as we found a significant number of new lineages in this host, which occupies regions with different climate characteristics where environmental variables exert an influence on the diversity and prevalence of Plasmodium.

A Multicenter Lung Ultrasound Study on Transient Tachypnea of the Neonate.

BACKGROUND AND AIM: Discordant results that demand clarification have been published on diagnostic lung ultrasound (LUS) signs of transient tachypnea of the neonate (TTN) in previous cross-sectional, single-center studies. This work was conducted to correlate clinical and imaging data in a longitudinal and multicenter fashion. METHODS: Neonates with a gestational age of 34-40 weeks and presenting with TTN underwent a first LUS scan at 60-180 min of life. LUS scans were repeated every 6-12 h if signs of respiratory distress persisted. Images were qualitatively described and a LUS aeration score was calculated. Clinical data were collected during respiratory distress. RESULTS: We enrolled 65 TTN patients. Thirty-one (47.6%) had a sharp echogenicity increase in the lower lung fields (the "double lung point" or DLP sign). On admission, there was no significant difference between patients with and without DLP in Silverman scores (4 ± 1.5 vs. 4 ± 2.1; p = 0.9) or LUS scores (7.6 ± 2.6 vs. 5.6 ± 3.8; p = 0.12); PaO2/FiO2 (249 ± 93 vs. 252 ± 125; p = 0.91). All initial LUS scans (performed at the onset of distress) and 99.5% of all scans showed a regular pleural line with no consolidation, with only 1 neonate showing consolidation in the follow-up scans. The Silverman and LUS scores were significantly correlated (rho = 0.27; p = 0.02). CONCLUSION: A regular pleural line with no consolidation is a consistent finding in TTN. The presence of a DLP is not essential for the LUS diagnosis of TTN. A semi-quantitative LUS score correlates well with the clinical course and could be useful in monitoring changes in lung aeration during TTN.

Considerations for monitoring population trends of colonial waterbirds using the effective number of breeders and census estimates.

Detecting trends in population size fluctuations is a major focus in ecology, evolution, and conservation biology. Populations of colonial waterbirds have been monitored using demographic approaches to determine annual census size (Na). We propose the addition of genetic estimates of the effective number of breeders (Nb) as indirect measures of the risk of loss of genetic diversity to improve the evaluation of demographics and increase the accuracy of trend estimates in breeding colonies. Here, we investigated which methods of the estimation of Nb are more precise under conditions of moderate genetic diversity, limited sample sizes and few microsatellite loci, as often occurs with natural populations. We used the wood stork as a model species and we offered a workflow that researchers can follow for monitoring bird breeding colonies. Our approach started with simulations using five estimators of Nb and the theoretical results were validated with empirical data collected from breeding colonies settled in the Brazilian Pantanal wetland. In parallel, we estimated census size using a corrected method based on counting active nests. Both in simulations and in natural populations, the approximate Bayesian computation (ABC) and sibship assignment (SA) methods yielded more precise estimates than the linkage disequilibrium, heterozygosity excess, and molecular coancestry methods. In particular, the ABC method performed best with few loci and small sample sizes, while the other estimators required larger sample sizes and at least 13 loci to not underestimate Nb. Moreover, according to our Nb/Na estimates (values were often ≤0.1), the wood stork colonies evaluated could be facing the loss of genetic diversity. We demonstrate that the combination of genetic and census estimates is a useful approach for monitoring natural breeding bird populations. This methodology has been recommended for populations of rare species or with a known history of population decline to support conservation efforts.

Effects of habitat suitability for vectors, environmental factors and host characteristics on the spatial distribution of the diversity and prevalence of haemosporidians in waterbirds from three Brazilian wetlands.

BACKGROUND: Wetlands are ecosystems in which vectors of avian haemosporidians live and reproduce and where waterbirds join to breed in colonies. Brazil has wetlands at different latitudes, which enables testing the influence of the ecological factors on the prevalence and diversity of haemosporidians. We identified avian haemosporidians in waterbird species in three wetlands and investigated the effects of vector habitat suitability, landscape and host characteristics on the diversity and prevalence of these parasites. METHODS: We created a map with the probability of occurrence of avian haemosporidian vectors using maximum-entropy modelling based on references addressing species known to be vectors of haemosporidians in birds in Brazil. We determined the prevalence and diversity index of haemosporidians in the great egret (Ardea alba) (n = 129) and roseate spoonbill (Platalea ajaja) (n = 180) and compared the findings to data for the wood stork (Mycteria americana) (n = 199). RESULTS: We report the first record of Plasmodium in the family Threskiornithidae: four lineages in the roseate spoonbill, which also presented one lineage of Haemoproteus. In the family Ardeidae, we found three Plasmodium lineages in the great egret. The similar habitat suitability for vectors found in three wetlands explains the pattern of haemosporidian diversity determined for great egret and wood stork populations. Comparisons of haemosporidian diversity within each waterbird species and between regions showed a higher level in the central-western roseate spoonbill population than in the northern population (P = 0.021). Removing the host effect, we discussed the results obtained in terms of characteristics of the Pantanal region. Comparisons of Plasmodium spp. prevalence among waterbird species within the same wetland showed higher level in roseate spoonbill (74%) than those found in the great egret (21%) and wood stork (11%). Excluding the environmental effect, we interpreted result focusing host characteristics that favour infection: time required for nestlings to be covered by feathers and migratory behaviour. CONCLUSIONS: The map of habitat suitability showed that wetlands located in a 30° latitudinal range offer similar conditions for avian vectors species and diversity of haemosporidians. The lineages described in waterbirds were previously identified in birds of prey as Plasmodium paranucleophilum.

Use of noninvasive 'bug-eggs' to enable comparative inferences on genetic mating system with and without parental information: A study in a cattle egret colony.

Colonial waterbirds such as herons, egrets and spoonbills exhibit ecological characteristics that could have promoted the evolution of conspecific brood parasitism and extra-pair copulation. However, an adequate characterization of the genetic mating systems of this avian group has been hindered by the lack of samples of elusive candidate parents which precluded conducting conventional parentage allocation tests. Here, we investigate the genetic mating system of the invasive cattle egret using hematophagous insects contained in fake eggs to collect blood from incubating adults in a wild breeding colony. We tested a protocol with a previously unused Neotropical Triatominae, Panstrongylus megistus, obtained blood samples from males and females in 31 nests built on trees, drew blood from 89 nestlings at those nests, and genotyped all samples at 14 microsatellite loci, including six new species-specific loci. We comparatively addressed the performance of parentage allocation versus kinship classification of nestlings to infer the genetic mating system of cattle egrets. In line with previous behavioral observations, we found evidence in support of a non-monogamous genetic mating system, including extra-pair paternity (EPP) and conspecific brood parasitism (CBP). Parentage allocation tests detected a higher percentage of nests with alternative reproductive tactics (EPP: 61.7%; CBP: 64.5%) than the kinship classification method (EPP: 50.0%; CBP: 43.3%). Overall, these results indicate that rates of alternative reproductive tactics inferred in the absence of parental genetic information could be underestimated and should be interpreted with caution. This study highlights the importance of incorporating samples from candidate parents to adequately determine the genetic mating system of a species. We expand knowledge on the reproductive tactics of colonial waterbirds, contributing novel data on the genetic mating system of the cattle egret, valuable for the design of management strategies for this invasive bird.

Immunoglobulins in neonatal sepsis: has the final word been said?

Systemic infection is a major cause of mortality and morbidity among premature neonates. In this fragile population, the immaturity of the innate immune response relates inversely to gestational age and is one of the determinants of susceptibility to infections. Antibiotic therapy, even when appropriately and timely instituted, may fail to prevent death or significant sequelae. The quest for additional strategies is still open; in this scenario, the supplementation with exogenous immunoglobulins represents an attractive additional strategy of defence. As current data are conflicting, we provide a critical appraisal with a focus on IgM enriched immunoglobulins preparations.

Use of neonatal chest ultrasound to predict noninvasive ventilation failure.

BACKGROUND: Noninvasive ventilation is the treatment of choice for neonatal moderate respiratory distress (RD). Predictors of nasal ventilation failure are helpful in preventing clinical deterioration. Work on neonatal lung ultrasound has shown that the persistence of a hyperechogenic, "white lung" image correlates with severe distress in the preterm infant. We investigate the persistent white lung ultrasound image as a marker of noninvasive ventilation failure. METHODS: Newborns admitted to the NICU with moderate RD and stabilized on nasal continuous positive airway pressure for 120 minutes were enrolled. Lung ultrasound was performed and blindly classified as type 1 (white lung), type 2 (prevalence of B-lines), or type 3 (prevalence of A-lines). Chest radiograph also was examined and graded by an experienced radiologist blind to the infant's clinical condition. Outcome of the study was the accuracy of bilateral type 1 to predict intubation within 24 hours from scanning. Secondary outcome was the performance of the highest radiographic grade within the same time interval. RESULTS: We enrolled 54 infants (gestational age 32.5 ± 2.6 weeks; birth weight 1703 ± 583 g). Type 1 lung profile showed sensitivity 88.9%, specificity 100%, positive predictive value 100%, and negative predictive value 94.7%. Chest radiograph had sensitivity 38.9%, specificity 77.8%, positive predictive value 46.7%, and negative predictive value 71.8%. CONCLUSIONS: After a 2-hour nasal ventilation trial, neonatal lung ultrasound is a useful predictor of the need for intubation, largely outperforming conventional radiology. Future studies should address whether including ultrasonography in the management of neonatal moderate RD confers clinical advantages.

Genetic differentiation among populations of the Roseate Spoonbill (Platalea ajaja; Aves: Pelecaniformes) in three Brazilian Wetlands.

Effective population size, levels of genetic diversity, gene flow, and genetic structuring were assessed in 205 colonial Roseate spoonbills from 11 breeding colonies from north, central west, and south Brazil. Colonies and regions exhibited similar moderate levels of diversity at five microsatellite loci (mean expected heterozygosity range 0.50-0.62; allelic richness range 3.17-3.21). The central west region had the highest Ne (59). F ST values revealed low but significant genetic structuring among colonies within the north and within the south regions. Significant global genetic structuring was found between the northern and central western populations as well as between the northern and southern populations. An individual-based Bayesian clustering method inferred three population clusters. Assignment tests correctly allocated up to 64% of individuals to their source regions. Collectively, results revealed complex demographic dynamics, with ongoing gene flow on a local scale, but genetic differentiation on a broader scale. Populations in the three regions may all be conserved, but special concern should be given to central western ones, which can significantly contribute to the species' gene pool in Brazil.

Are IgM-enriched immunoglobulins an effective adjuvant in septic VLBW infants?

AIM: To investigate the effectiveness of IgM-enriched immunoglobulins (IgM-eIVIG) in reducing short-term mortality of neonates with proven late-onset sepsis. METHODS: All VLBW infants from January 2008 to December 2012 with positive blood culture beyond 72 hours of life were enrolled in a retrospective cohort study. Newborns born after June 2010 were treated with IgM-eIVIG, 250 mg/kg/day iv for three days in addition to standard antibiotic regimen and compared to an historical cohort born before June 2010, receiving antimicrobial regimen alone. Short-term mortality (i.e. death within 7 and 21 days from treatment) was the primary outcome. Secondary outcomes were: total mortality, intraventricular hemorrhage, necrotizing enterocolitis, periventricular leukomalacia, bronchopulmonary dysplasia at discharge. RESULTS: 79 neonates (40 cases) were enrolled. No difference in birth weight, gestational age or SNAP II score (disease severity score) were found. Significantly reduced short-term mortality was found in treated infants (22% vs 46%; p = 0.005) considering all microbial aetiologies and the subgroup affected by Candida spp. Secondary outcomes were not different between groups. CONCLUSION: This hypothesis-generator study shows that IgM-eIVIG is an effective adjuvant therapy in VLBW infants with proven sepsis. Randomized controlled trials are warranted to confirm this pilot observation.

Conspecific brood parasitism in the white-faced ibis Plegadis chihi (Aves: Pelecaniformes) revealed by microsatellites' based kinship-reconstruction.

The white-faced ibis Plegadis chihi Vieillot, 1817 (Pelecaniformes: Threskiornithidae) is a socially monogamous colonially breeding bird in which behavioral and ecological observations suggest the occurrence of conspecific brood parasitism (CBP). We inferred aspects of the genetic mating system of P. chihi in nature, using a genetic approach in the absence of parental information. We used five heterologous microsatellite loci and a multiple-step methodological approach to infer kinship patterns among 104 pairs of nestlings sampled inside 80 nests in a breeding colony from southern Brazil. The estimated effective population size was 69 white-faced ibises (95% CI: 50-98), enough to ensure long-term population survival. Kinship patterns were identified for 38% of the analyzed pairs: 60% of the diagnosed pairs were identified as full-siblings, 2.5% as half-siblings and 37.5% as unrelated individuals. CBP could explain the presence of unrelated nestlings within broods, in agreement with available non-genetic evidence. The presence of half-siblings within broods could indicate extra-pair paternity. Results suggest that a non-strictly monogamous genetic mating system may be present in the white-faced ibis. This study is the first molecular approach to better characterize the reproductive behavior of P. chihi in the wild. Our findings set the stage for further research to investigate the possible causes and consequences of alternative reproductive strategies in this species.

Inferred kinship patterns reveal low levels of extra-pair paternity in the endangered Neotropical Jabiru Stork (Jabiru mycteria, Aves: Ciconiiformes).

The present study inferred the genetic mating system in a natural breeding population of the Jabiru Stork (Jabiru mycteria), a Neotropical wading bird considered endangered in part of its distribution range. Based on data from eight microsatellite loci, maximum-likelihood kinship reconstruction techniques, parentage assignment analyses and effective population size (Ne) estimates were applied to samples collected in the Brazilian Pantanal wetland (N = 45 nestlings from 20 nests; N = 17 shed adult feathers from 11 nests). The relationship diagnosis was determined for most of the complete clutches (86.66 %): 92.31 % were full siblings and 7.69 % were half siblings. Shed feathers collected from the nests matched the genetic parents of the offspring in 80 % of cases. Feathers collected from the ground below the nests were compatible with the putative parents in 41.67 % of cases. A mean Ne of 35 reproductive individuals was inferred, corresponding to an Ne/Nc ratio of 0.09, which is similar to the ratio found in populations of a number of different wild animals. The higher proportion of full siblings identified in the broods suggests that genetic monogamy is the prevalent mating system in the Jabiru Stork, while the detection of half siblings suggests some degree of extra-pair paternity. The present findings are in agreement with previous ecological observations of social monogamy in this species, despite the isolated evidence of extra-pair copulation events. This study also demonstrates the usefulness of a noninvasive approach to sampling adults and performing parentage and relatedness analyses in an elusive, threatened species.

Blood parasites in nestlings of wood stork populations from three regions of the American continent.

This study documents the prevalences and lineages of hemoparasites in wood stork nestlings from 3 regions of the American continent: southeastern United States (n = 90), northern Brazil (n = 74), and central-western Brazil (n = 125). Identification was based on PCR amplification of a mitochondrial small subunit ribosomal RNA gene. A fragment of the hemoparasite cytochrome B gene in infected individuals was utilized for Bayesian phylogenetic analysis. Four wood stork nestlings were infected by Haemoproteus, 1 from northern Brazil and 3 from the United States, and all shared the same haplotype. Morphological analysis confirmed the infection of the U.S. birds by Haemoproteus. Infection by Plasmodium was found in wood stork nestlings from northern (6) and central-western Brazil (14). Five Plasmodium lineages (MYCAMP1-2, and MYCAMP4-6) were found in the Brazilian central-western region and 3 Plasmodium lineages (MYCAMP2-3, and MYCAMP7) were found in the northern region. The most prevalent haplotype (MYCAMP2) differs from the others by 1 mutation, and the less prevalent haplotypes are derived from MYCAMP2. We did not find Plasmodium or Haemoproteus in nestlings younger than 15 and 30 days old, respectively. This is the first documentation of Plasmodium and Haemoproteus infection in wood storks in Brazilian breeding populations. Potential connectivity among wood stork populations was indirectly supported by the presence of identical Haemoproteus lineages in U.S. and northern Brazilian populations, and by the presence of identical Plasmodium haplotypes in the northern and central-western Brazilian populations.

Measuring transcutaneous bilirubin: a comparative analysis of three devices on a multiracial population.

BACKGROUND: Hyperbilirubinemia can lead to potentially irreversible bilirubin-induced neurotoxicity. Transcutaneous bilirubin (TcB) determination has become a valuable aid in non invasive screening of neonatal jaundice.The aim of this study is to compare the performance of three most widespread transcutaneous bilirubinometers on a multiracial population of term and late pre-term neonates. METHODS: Bilirubin concentration was determined using traditional photometric determination and transcutaneously with Bilicheck, BiliMed and JM-103, in random order.Total serum bilirubin (TSB) was determined over a wide concentration range (15,8-0,7 mg/dl) with a mean of 9,5 mg/dl. Related TcB values using Bilicheck (TcB-BC), BiliMed (TcB-BM), and JM-103 (TcB-JM) are reported in Table 1. RESULTS: A multiracial population of 289 neonates was enrolled with a gestational age ranging from 35 to 41 weeks; birth weight ranging from 1800 to 4350 grams; hours of life ranging from 4 to 424. In the total study population correlation analysis using Pearson coefficients showed good results for Bilicheck (r = 0.86) and JM-103 (r = 0.85) but poor for BiliMed (r = 0,70). Similar results were found for the non-Caucasian neonates subgroup. Bilicheck and JM-103 had a greater area under the curve than BiliMed when TSB =14 mg/dl was chosen as a threshold value both for the total study population and the non-Caucasian subgroup. CONCLUSIONS: Bilicheck and JM-103, but not BiliMed, are equally reliable screening tools for hyperbilirubinemia in our multiracial neonatal population.

Polymorphic heterologous microsatellite loci for population genetics studies of the white-faced ibis Plegadis chihi (Vieillot, 1817) (Pelecaniformes, Threskiornithidae).

We screened 44 heterologous microsatellites isolated in species of the families Threskiornithidae, Ciconiidae and Ardeidae for their use in a migratory waterbird, the white-faced ibis Plegadis chihi (Vieillot, 1817) (Threskiornithidae). Of the screened loci, 57% amplified successfully and 24% were polymorphic. In two breeding colonies from southern Brazil (N = 131) we detected 32 alleles (2-10 alleles/locus). Average He over all loci and colonies was 0.55, and the combined probability of excluding false parents, 98%. There was no departure from HWE in any loci or population. Eru6 and Eru4 loci were in non-random association in the Alvorada colony, and NnNF5 and Eru5 in both populations. AMOVA analysis indicated that most of the genetic diversity was contained within populations. Structure analysis suggested a single population, and F(ST) value showed weak genetic structuring (F(ST) = 0.009, p = 0.05). The two populations are apparently connected through gene-flow. The panel of six microsatellites optimized here was sufficiently informative for characterizing the genetic diversity and structure in these natural populations of the white-faced ibis. The information generated could be useful in future studies of genetic diversity, relatedness and the mating system in Plegadis chihi and related species.

Polymorphic heterologous microsatellite loci for population genetics studies of the white-faced ibis Plegadis chihi (Vieillot, 1817) (Pelecaniformes, Threskiornithidae)

We screened 44 heterologous microsatellites isolated in species of the families Threskiornithidae, Ciconiidae and Ardeidae for their use in a migratory waterbird, the white-faced ibis Plegadis chihi (Vieillot, 1817) (Threskiornithidae). Of the screened loci, 57 percent amplified successfully and 24 percent were polymorphic. In two breeding colonies from southern Brazil (N = 131) we detected 32 alleles (2-10 alleles/ locus). Average He over all loci and colonies was 0.55, and the combined probability of excluding false parents, 98 percent. There was no departure from HWE in any loci or population. Eru6 and Eru4 loci were in non-random association in the Alvorada colony, and NnNF5 and Eru5 in both populations. AMOVA analysis indicated that most of the genetic diversity was contained within populations. Structure analysis suggested a single population, and F ST value showed weak genetic structuring (F ST = 0.009, p = 0.05). The two populations are apparently connected through gene-flow. The panel of six microsatellites optimized here was sufficiently informative for characterizing the genetic diversity and structure in these natural populations of the white-faced ibis. The information generated could be useful in future studies of genetic diversity, relatedness and the mating system in Plegadis chihi and related species.

Sedentary nestlings of Wood Stork as monitors of mercury contamination in the gold mining region of the Brazilian Pantanal.

Sedentary organisms that are at top trophic levels allow inference about the level of local mercury contamination. We evaluated mercury contamination in feather tissue of nestling Wood Storks (Mycteria americana), sampled in different parts of the Brazilian Pantanal that were variably polluted by mercury releases from gold mining activities. Levels of mercury in feathers sampled in seven breeding colonies were determined by atomic absorption spectroscopy, and the mean value of mercury concentration was 0.557 µg/g, dry weight (n=124), range 0.024-4.423 µg/g. From this total sample, 21 feathers that represent 30% of nestlings collected in Porto da Fazenda and Tucum colonies, in the northern region, ranged from 1.0 to 4.43 µg/g, dry weight (median value=1.87 µg/g). We found significant differences among regions (H=57.342; p=0<0.05). Results suggest that permanently flooded areas, or along mainstream rivers are more contaminated by mercury than dry areas, regardless of the distance from the gold mining center, which is located in the northern Pantanal. Highest values found in nestlings feathers were similar to those found in feathers of adult birds and in tissues of adult mammals that are less sedentary and were captured in the same region of Pantanal. These findings indicate that mercury released has been biomagnified and it is present in high concentrations in tissues of top consumers. We suggest a program to monitor mercury availability in this ecosystem using sedentary life forms of top predators like Wood Storks or other piscivorous birds.

Reconstructing genetic mating systems in the absence of parental information in colonially breeding waterbirds.

BACKGROUND: DNA-based studies have demonstrated that avian genetic mating systems vary widely, with many species deviating from long-assumed monogamy by practicing extra-pair paternity and conspecific brood parasitism. Colonially breeding waterbirds provide interesting models in which to investigate this question because they show nesting habits proposed to promote alternative reproductive strategies. However, little is known about the genetic mating systems of this group of birds, mainly due to difficulties in obtaining genetic data from incubating adults at nests that are necessary for conducting conventional parentage studies. Here, we inferred kinship patterns among offspring in broods of three co-distributed waterbird species, Wood Stork (Mycteria americana), Roseate Spoonbill (Platalea ajaja) and Great Egret (Ardea alba egretta), to investigate genetic mating system in the absence of parental data. RESULTS: Multi-step analyses combining estimates of relatedness coefficients, formulation of relationship-hypotheses, significance testing of alternative hypotheses, and maximum-likelihood sibship reconstruction techniques revealed evidence that alternative reproductive strategies may be present in natural populations of Wood Storks and Roseate Spoonbills, whereas relatedness of co-nestlings diagnosed in the Great Egrets did not deviate from a hypothesis of genetic monogamy. Specifically, under this analytical framework, inferred kinship relationships revealed that Great Egret nests contained full-sibling nestlings (100%), with the Roseate Spoonbill (RS) and Wood Stork (WS) exhibiting proportions of half-siblings (RS: 5%) and/or unrelated nestlings (RS: 24%; WS: 70%), patterns consistent with extra-pair paternity and conspecific brood parasitism, respectively. CONCLUSIONS: We provide evidence that genetic monogamy occurs in Brazilian natural breeding colonies of the Great Egret, but is not the sole reproductive strategy employed by the Wood Stork and the Roseate Spoonbill. In fact, extra-pair paternity and conspecific brood parasitism were common in the latter two species, with a combined frequency of 7.5% and 11.3% in Roseate Spoonbill and Wood Stork, respectively. Although geographically co-distributed, differences among these species may be due to variation in their life histories. From a methodological standpoint, the approach implemented here, although not free from limitations, can have broad application for analyzing systems with limited genealogical information and/or in studying similarly challenging organisms in which obtaining genetic data on complete families is problematic.