The Fecal Viral Flora of Wild Rodents

The frequent interactions of rodents with humans make them a common source of zoonotic infections. To obtain an initial unbiased measure of the viral diversity in the enteric tract of wild rodents we sequenced partially purified, randomly amplified viral RNA and DNA in the feces of 105 wild rodents (mouse, vole, and rat) collected in California and Virginia. We identified in decreasing frequency sequences related to the mammalian viruses families Circoviridae, Picobirnaviridae, Picornaviridae, Astroviridae, Parvoviridae, Papillomaviridae, Adenoviridae, and Coronaviridae. Seventeen small circular DNA genomes containing one or two replicase genes distantly related to the Circoviridae representing several potentially new viral families were characterized. In the Picornaviridae family two new candidate genera as well as a close genetic relative of the human pathogen Aichi virus were characterized. Fragments of the first mouse sapelovirus and picobirnaviruses were identified and the first murine astrovirus genome was characterized. A mouse papillomavirus genome and fragments of a novel adenovirus and adenovirus-associated virus were also sequenced. The next largest fraction of the rodent fecal virome was related to insect viruses of the Densoviridae, Iridoviridae, Polydnaviridae, Dicistroviriade, Bromoviridae, and Virgaviridae families followed by plant virus-related sequences in the Nanoviridae, Geminiviridae, Phycodnaviridae, Secoviridae, Partitiviridae, Tymoviridae, Alphaflexiviridae, and Tombusviridae families reflecting the largely insect and plant rodent diet. Phylogenetic analyses of full and partial viral genomes therefore revealed many previously unreported viral species, genera, and families. The close genetic similarities noted between some rodent and human viruses might reflect past zoonoses. This study increases our understanding of the viral diversity in wild rodents and highlights the large number of still uncharacterized viruses in mammals

Biodisponibilidade do cálcio dietético

O cálcio (Ca) dietético é fundamental para a saúde óssea. Tanto o teor como a biodisponibilidade do elemento nos alimentos devem ser considerados. Este artigo objetiva sumarizar os fatores envolvidos na absorção e destacar os alimentos com melhor disponibilidade do Ca. Este é absorvido principalmente no jejuno e o pH baixo parece favorecer sua absorção, que é maior no crescimento, na gestação/lactação e na carência de Ca ou fósforo (P), e menor no envelhecimento. As maiores fontes, e com melhor absorção, são os laticínios bovinos. Outros alimentos apresentam concentrações elevadas de Ca, mas com biodisponibilidade variável: os ricos em ácidos oxálico e fítico apresentariam uma menor absorção, enquanto que os ricos em carboidratos teriam uma absorção maior. Por apresentarem uma biodisponibilidade do Ca mais próxima da do leite bovino, o leite de outros animais, o de soja enriquecido e alguns vegetais, em quantidades adequadas, poderiam ser usados como alternativas a este.Dietary calcium (Ca) is fundamental to the bone's health. Both the purport and the element bioavailability in the food need to be considered. The purpose of this work was to summarize the factors involved in Ca absorption and point out the sources with higher bioavailability. Ca is mostly absorbed in the jejunum and low pH seems to favor its absorption, which is higher during growth, gestation/lactation and Ca and phosphorus (P) deficiency, and lower with aging. The richest and best-absorbed Ca source is cow's milk and its derivatives. Other foods show high Ca concentrations but variable bioavailability: foods rich in phytates and oxalates show a smaller absorption and carbohydrate-rich foods show higher absorption. Since Ca bioavailability in other animal's milk, soymilk and some vegetables is closer to that in cow's milk, adequate amounts of these foods could be used as an alternative

Importância de Cryptosporidium spp. como causa de diarréia em bezerros Importance of Cryptosporidium spp. as a cause of diarrhea in calves

Avaliou-se a presença de oocistos de Cryptosporidium spp. em amostras de fezes de 14 bezerros e de suas mães até a oitava semana pós parição. A maior taxa de excreção de oocistos foi verificada em bezerros com sete dias de idade. Das vacas, 42,8% foram positivas para Cryptosporidium no período pós-parto. Em outra etapa deste estudo, foram acompanhados 57 bezerros positivos para Cryptosporidium, com até 30 dias de idade, provenientes de 32 propriedades leiteiras, e estudouse o grau de eliminação dos oocistos com a possível ocorrência de diarréia. Em todos os animais positivos para Cryptosporidium foi pesquisada a presença de bactérias enteropatogênicas, vírus (Rotavirus e Coronavirus) e protozoários (Eimeria spp.).<br>The aim of this research was to evaluate the shedding of Cryptosporidium spp. oocysts in fecal samples from 14 calves from one dairy farm, from birth until 60 days old and from cows until eight weeks after parturition. The higher percentage of oocysts excreted was observed in 7-day-old calves. In the post-partum period 43.7% of cows were positive for Cryptosporidium oocysts. Further analyses were accomplished in 57 calves from another 32 milk farms, previously known as positive for Cryptosporidium, through oocysts fecal screening and clinical signs analyses until calves were 30 days old. Fecal samples from all animals that presented diarrhea were screened for the presence of bacteria, virus (Rotavirus and Coronavirus ) and protozoa (Eimeria spp.)

Picovirnavirus

Picobirnaviruses (PBVs) recently occupied a place in the list of entericviruses and are highly versatile due to their huge genetic diversity and wide hostrange. PBVs are small, non-enveloped viruses carrying a bi-segmented double-stranded RNA genome and have been placed within a new family?Picobirnaviridae?. Nevertheless, PBVs have been detected primarily from thefaeces of many host species, these viruses have also been reported in the respiratorytract of pigs and plasma of horses that needs further investigation for their inhabitantbehaviour. Based on the available information, PBVs may be considered as oppor-tunistic enteric pathogens; however, prokaryotic ribosomal binding motifs have beenidentified in many PBV gene segments, indicating that these may be prokaryoticviruses. Though PBVs may have an ambiguous clinical implication, they might posea potential public health concern. Because of lack of suitable animal model/cell lines,there remains an uncertainty on the pathogenesis, persistence, and evolution ofPBVs. The control of PBVs largely depends on the non-vaccine approach.Fil: Kumar, Naveen. National Institute Of High Security Animal Diseases; IndiaFil: D'Arc Pereira Mascarenhas, Joana. Evandro Chagas Institute. Virology Section; BrasilFil: Ghosh, Souvik. Ross University School of Veterinary Medicine. Department Of Biomedical Sciences. One Health Center; Trinidad y TobagoFil: Masachessi, Gisela. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de Virología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: da Silva Bandeira, Renato. Evandro Chagas Institute. Virology Section; BrasilFil: Nates, Silvia Viviana. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de Virología; ArgentinaFil: Dhama, Kuldeep. Indian Veterinary Research Institute; IránFil: Kumar Singh, Raj. Indian Veterinary Research Institute; IránFil: Singh Malik, Yashpal. Indian Veterinary Research Institute; Irá