Thank you for biting: dispersal of beneficial microbiota through 'antagonistic' interactions.

Multicellular organisms harbor populations of microbial symbionts; some of these symbionts can be dispersed through the feeding activities of consumers. Studies of consumer-mediated microbiota dispersal generally focus on pathogenic microorganisms; the dispersal of beneficial microorganisms has received less attention, especially in the context of 'antagonistic' trophic interactions (e.g., herbivory, parasitism, predation). Yet, this 'trophic transmission' of beneficial symbionts has significant implications for microbiota assembly and resource species (e.g., prey) health. For example, trophic transmission of microorganisms could assist with environmental acclimatization and help resource species to suppress other consumers or competitors. Here, we highlight model systems and approaches that have revealed these potential 'silver-linings' of antagonism as well as opportunities and challenges for future research.

Alphaflexivirus Genomes in Stony Coral Tissue Loss Disease-Affected, Disease-Exposed, and Disease-Unexposed Coral Colonies in the U.S. Virgin Islands.

Stony coral tissue loss disease (SCTLD) is decimating Caribbean corals. Here, through the metatranscriptomic assembly and annotation of two alphaflexivirus-like strains, we provide genomic evidence of filamentous viruses in SCTLD-affected, -exposed, and -unexposed coral colonies. These data will assist in clarifying the roles of viruses in SCTLD.

Direct evidence of sex and a hypothesis about meiosis in Symbiodiniaceae.

Dinoflagellates in the family Symbiodiniaceae are obligate endosymbionts of diverse marine invertebrates, including corals, and impact the capacity of their hosts to respond to climate change-driven ocean warming. Understanding the conditions under which increased genetic variation in Symbiodiniaceae arises via sexual recombination can support efforts to evolve thermal tolerance in these symbionts and ultimately mitigate coral bleaching, the breakdown of the coral-Symbiodiniaceae partnership under stress. However, direct observations of meiosis in Symbiodiniaceae have not been reported, despite various lines of indirect evidence that it occurs. We present the first cytological evidence of sex in Symbiodiniaceae based on nuclear DNA content and morphology using Image Flow Cytometry, Cell Sorting and Confocal Microscopy. We show the Symbiodiniaceae species, Cladocopium latusorum, undergoes gamete conjugation, zygote formation, and meiosis within a dominant reef-building coral in situ. On average, sex was detected in 1.5% of the cells analyzed (N = 10,000-40,000 cells observed per sample in a total of 20 samples obtained from 3 Pocillopora colonies). We hypothesize that meiosis follows a two-step process described in other dinoflagellates, in which diploid zygotes form dyads during meiosis I, and triads and tetrads as final products of meiosis II. This study sets the stage for investigating environmental triggers of Symbiodiniaceae sexuality and can accelerate the assisted evolution of a key coral symbiont in order to combat reef degradation.

Factors associated with infant feeding practices after hospital discharge.

OBJECTIVE: To assess factors associated with infant feeding practices on the first day at home after hospital discharge. METHODS: A total of 209 women, who had a child aged four months or less and were living in Itapira, Brazil, were interviewed during the National Immunization Campaign Day in 1999. Statistical analysis was performed using the Chi-square test and a logistic regression model was used for verifying an association between dependent and independent variables. RESULTS: Women aged 25.5 years on average and 18.2% were teenagers. Fifty-three percent of the women delivered vaginally and most vaginal deliveries (78.5%) took place in the public hospital. The prevalence of exclusive breastfeeding on the first day at home was 78.1% and 11.6% of the infants were receiving formula at this time. The only factor associated with EBF on the first day at home was being a teenaged-primiparous mother (OR=9.40; 95% CI: 1.24-71.27). This association remained statistically significant even after controlling for type of delivery and hospital where the birth took place. Feeding formula on the first day at home was only significantly associated with the hospital (i.e., birth at the city hospital was a protective factor (OR=0.33; 95% CI: 0.13-0.86), even after controlling for vaginal delivery. CONCLUSIONS: On the first day at home after hospital discharge, teenaged-primiparous mothers were more likely to exclusive breastfeeding as well as those infants born in the municipal public hospital. Further studies are needed from a multidisciplinary approach.

Factors associated with infant feeding practices after hospital discharge

OBJETIVO: Avaliar os fatores associados à prática de amamentação no primeiro dia em casa após a alta hospitalar. MÉTODOS: Foram realizadas 209 entrevistas com mães de lactentes, com idade até quatro meses de vida, residentes em Itapira, SP, no momento em que levaram seus filhos para serem vacinados durante a Campanha Nacional de Vacinação, em 1999. Utilizou-se de análise exploratória dos dados, teste do qui-quadrado. Verificou-se associação entre as variáveis dependentes e independentes por análise de regressão logística. RESULTADOS: Observou-se, que a idade média das mães foi de 25,5 anos e 18,2% eram mães adolescentes. Nasceram por parto vaginal 53% dos lactentes, sendo a maioria (78,5%) em hospital municipal. Constatou-se que 78,1% dos lactentes no primeiro dia em casa encontravam-se em aleitamento materno exclusivo e 11,6% já haviam consumido outros alimentos. O único fator associado à maior chance de estar amamentando exclusivamente no primeiro dia em casa foi o fato de a mãe ser adolescente e primípara (OR=9,40; IC 95% (OR)=1,24-71,27), ajustado para o tipo de parto e hospital de nascimento. Em relação ao uso de leite artificial no primeiro dia em casa, a mãe atendida no hospital municipal teve menor chance de usar leite artificial (OR=0,33; IC 95% (OR)=0,13-0,86), mesmo após o controle para o parto vaginal. CONCLUSÕES: No primeiro dia em casa após alta hospitalar, adolescentes primíparas tiveram maior chance de amamentar exclusivamente, assim como aquelas crianças que nasceram no hospital municipal. Sugere-se a realização de outros estudos, que contemplem uma abordagem multidisciplinar.