Widespread distribution of CTX-M and plasmid-mediated AmpC β-lactamases in Escherichia coli from Brazilian chicken meat

The dissemination of plasmid-mediated antimicrobial resistance genes may pose a substantial public health risk. In the present work, the occurrences ofblaCTX-M and plasmid-mediated ampCand qnrgenes were investigated in Escherichia colifrom 16 chicken carcasses produced by four commercial brands in Brazil. Of the brands tested, three were exporters, including one of organic chicken. Our study assessed 136 E. coli isolates that were grouped into 77 distinct biotypes defined by their origin, resistance profiling, the presence of β-lactamase and plasmid-mediated quinolone resistance genes and enterobacterial repetitive intergenic consensus-polimerase chain reaction typing. TheblaCTX-M-15, blaCTX-M-2 andblaCTX-M-8 genes were detected in one, 17 and eight different biotypes, respectively (45 isolates). Twenty-one biotypes (46 isolates) harboured blaCMY-2.Additionally, blaCMY-2 was identified in isolates that also carried either blaCTX-M-2 orblaCTX-M-8. The qnrB and/orqnrS genes occurred in isolates carrying each of the four types of β-lactamase determinants detected and also in oxyimino-cephalosporin-susceptible strains. Plasmid-mediated extended-spectrum β-lactamase (ESBL) and AmpC determinants were identified in carcasses from the four brands tested. Notably, this is the first description ofblaCTX-M-15 genes in meat or food-producing animals from South America. The blaCTX-M-8, blaCTX-M-15 andblaCMY-2 genes were transferable in conjugation experiments. The findings of the present study indicate that plasmid-mediated ESBL and AmpC-encoding genes are widely distributed in Brazilian chicken meat.

Should I go to court?: an assessment of the role of the Judiciary in disputes between cattle raisers and meatpackers in Brazil

The main objective of this perspective paper is to analyze the role of the judiciary in resolving conflicts between cattle raisers and meatpacking firms in Brazil. Looking at the transaction for the acquisition of cattle for slaughter in the state of Mato Grosso do Sul (the central-western region of Brazil), the analysis encompasses three steps. First, the authors describe the transaction pattern between cattle raisers and meatpacking firms, identifying a guarantee vacuum within the supply chain. Secondly, the authors present evidence that the guarantee vacuum may give rise to legal conflicts of non-payment, which are indeed prevalent in disputes that reach the courts. Finally, the role of the judiciary in resolving these conflicts is investigated. Results suggest that, on average, producers have little confidence in the legal system, indicating the potential function that informal mechanisms may play in the supply chain. The paper concludes by suggesting some implications for public and private strategies.

Insects of forensic importance from Rio Grande do Sul state in southern Brazil

The experiment was conducted throughout the year 2005, at the Universidade Federal de Pelotas campus. The objectives of the study were to analyze the decomposition of rabbit (Oryctolagus cunniculus L.) with mean weight 2.67 Kg carcass and describe the interaction of insects acting on it, as well as the insect's potential use in legal medicine. We collected 5.239 insect specimens; 1.827 of them were obtained from larvae collected from carcasses and reared. The specimens were identified and 20 species were of forensic importance. The species Lucilia eximia (Wiedemann, 1819) and Chrysomya albiceps (Wiedemann, 1819) (Diptera, Calliphoridae) were better indicators of post-mortem interval (PMI) because they occurred in all seasons and were the first to reach the carcass. Hemilucilia semidiaphana (Rondani, 1850), H. segmentaria (Fabricius, 1805) (Diptera, Calliphoridae), Muscina stabulans (Fallén, 1817) and Synthesiomyia nudiseta (Wulp, 1883) (Diptera, Muscidae) can disclose death time because they occur only in certain months of the year. Oxyletrum discicolle (Brullé, 1840) (Coleoptera, Silphidae) and Dermestes maculates De Geer, 1774 (Coleoptera, Desmestidae) were found in advanced stages of decomposition.

Diagnosis and key of the main families and species of South American Coleoptera of forensic importance

The objective of this paper is to provide diagnosis and keys of the families and species, with illustrations of the main groups. A table of all related species recorded from South America is presented, including the substrate in which they were collected and their geographical distribution. The list comprises 221 species included in 15 families, of which 70% of the species are from Brazil. Scarabaeidae is the most diverse family with 121 species, followed by Staphylinidae with 68. Also we provide one database of Coleoptera species associated with carcasses in South America.

Nutritional ecology of blowflies (Diptera, Calliphoridae): estimates of critical larval weight for pupation on two different

Under natural environmental conditions, blowflies utilize discrete and ephemeral feeding resources such as decaying carcasses. Competition for food on such feeding substrates is usually very severe, and only the individuals that are capable of attaining the critical larval weight for pupation will be able to survive. This critical weight is hitherto unknown for several blowfly species; therefore, the current work is aimed at obtaining such a critical value for four blowfly species of the genera Chrysomya and Lucilia, deploying two types of feeding substrate, namely, artificial diet and macerated bovine meat. On the whole, the critical weights ranged from 30 to 35 mg. The lowest larval weight which permitted pupation was 30.0 mg for Chrysomya megacephala reared on macerated bovine meat. This species was also the best adapted to pupation at low larval weights in relation to the maximum larval weight for males. Regarding the pupation of females, the best-adapted individual was a C. albiceps specimen exhibiting a critical weight that was equal to 39.20 % of the maximum value obtained. Concerning all the species and diet types, the female individuals exhibited the lowest critical weights that produced viable pupae, probably representing an evolutionary strategy that favoured the survival of females, responsible for the egg formation, contributing to the establishment of future generations. Regarding the loss (in percentage) of adult biomass in relation to the third instar larvae, the females of C. megacephala lost less weight than males in both feeding substrates. On the other hand, such a loss of weight occurred in males of C. albiceps and L. cuprina.

The effect of environment on development and survival of pupae of the necrophagous fly Ophyra albuquerquei Lopes (Diptera, Muscidae)

The effect of environment on development and survival of pupae of the necrophagous fly Ophyra albuquerquei Lopes (Diptera, Muscidae). Species of Ophyra Robineau-Desvoidy, 1830 are found in decomposing bodies, usually in fresh, bloated and decay stages. Ophyra albuquerquei Lopes, for example, can be found in animal carcasses. The influence of environmental factors has not been evaluated in puparia of O. albuquerquei. Thus, the focus of this work was motivated by the need for models to predict the development of a necrophagous insect as a function of abiotic factors. Colonies of O. albuquerquei were maintained in the laboratory to obtain pupae. On the tenth day of each month 200 pupae, divided equally into 10 glass jars, were exposed to the environment and checked daily for adult emergence of each sample. We concluded that the high survival rate observed suggested that the diets used for rearing the larvae and maintaining the adults were appropriate. Also, the data adjusted to robust generalized linear models and there were no interruptions of O. albuquerquei pupae development within the limits of temperatures studied in southern Rio Grande do Sul, given the high survival presented.

Arthropods associated with pig carrion in two vegetation profiles of Cerrado in the State of Minas Gerais, Brazil

Forensic Entomology research has been concentrated in only a few localities of the "Cerrado" vegetation, the Brazilian Savannah. The present study had, as its objective, an examination of the diversity of arthropod fauna associated with the carcasses of Sus scrofa (Linnaeus) in this biome. The study was conducted during the dry and humid periods in two Cerrado vegetation profiles of the State of Minas Gerais. The decaying process was slower and greater quantities of arthropods were collected during the dry period. Insects represented 99% of 161,116 arthropods collected. The majority of these were Diptera (80.2%) and Coleoptera (8.8%). The entomofauna belong to 85 families and at least 212 species. Diptera were represented by 31 families and at least 132 species. Sarcophagidae (Diptera) and Scarabaeidae (Coleoptera) were the richest groups. Oxysarcodexia (Sarcophagidae) presented the largest number of attracted species, however none of these species bred in the carcasses. The Coleoptera collected belong to at least 50 species of 21 families. Among these species, Dermestes maculatus and Necrobia rufipes were observed breeding in the carcasses. This study showed species with potential importance for estimating the postmortem interval (PMI), indicative of seasonal and environmental type located.

Necrophagous species of Diptera and Coleoptera in northeastern Brazil: state of the art and challenges for the Forensic Entomologist

Inventories on necrophagous insects carried out in Brazil encompass mostly species from the southeastern and central-western regions of the country. This review aims to produce the first checklist of necrophagous Diptera and Coleoptera species of forensic relevance in northeastern Brazil, an area that concentrates high rates of homicides. We performed a literature survey on scientific articles, theses and dissertations regarding necrophagous insect species in the region, and contacted scientists who develop research on forensic entomology. Fifty-two species of Diptera belonging to eight families with previous record of necrophagy were reported in the region: Sarcophagidae, Calliphoridae, Muscidae, Fanniidae, Piophilidae, Phoridae, Anthomyiidae and Stratiomyidae. Coleopteran species from six families of forensic relevance were registered, although taxonomical identification remained superficial. Bait traps were the most frequent methodology used, followed by collection on animal carcasses. Seven Dipteran species from two families were registered on human cadavers. All species had been previously reported in other Brazilian states and/or other countries, although none has been effectively used in legal procedures in the region. The status of research on forensic entomology in northeastern Brazil is incipient, and the checklist produced here contributes to the knowledge on the local diversity of necrophagous insects.

First record of Chrysomya rufifacies (Macquart) (Diptera, Calliphoridae) from Brazil

First record of Chrysomya rufifacies (Macquart) (Diptera, Calliphoridae) from Brazil. In addition to its native fauna, the Neotropical region is known to be inhabited by four introduced species of blow flies of the genus Chrysomya. Up until now, only three of these species have been recorded in Brazil - Chrysomya albiceps (Wiedemann), Chrysomya megacephala (Fabricius), and Chrysomya putoria (Wiedemann). In South America, C. rufifacies (Macquart) has only been reported from Argentina and Colombia. This study records C. rufifacies from Brazil for the first time. The specimens were collected in an area of cerrado (savanna-like vegetation) in the municipality of Caxias in state of Maranhão, and were attracted by pig carcasses.

Dung beetle assemblages (Coleoptera, Scarabaeinae) in Atlantic forest fragments in southern Brazil

Dung beetle assemblages (Coleoptera, Scarabaeinae) in Atlantic forest fragments in southern Brazil. The beetles of the subfamily Scarabaeinae are important organisms that participate in the cycle of decomposition, especially in tropical ecosystems. Most species feed on feces (dung) or carcasses (carrion) and are associated with animals that produce their food resources. Dung beetles are divided into three functional groups: rollers, tunnelers and dwellers. This present work aims to study the diversity of dung beetle communities inhabiting fragments of the Atlantic Forest, with the purpose of describing the ecology of the species in southern Brazil. This study was conducted in the region of Campos Novos, in Santa Catarina, where twenty sites of Atlantic forest fragments were sampled. Samplings of dung beetles were conducted using 200 pitfall traps, of which 100 were baited with human feces and another 100 with carrion. Size and environmental complexity were also measured for each forest fragment. A total of 1,502 dung beetles, belonging to six tribes, 12 genera and 33 species, were collected. Results of the Levin's index of niche breadth indicated that 11 species were categorized as being coprophagous, ten as generalists, and two as necrophagous. Most species are tunnelers (19), nine of rollers and four of dwellers. The great diversity of Scarabaeinae in the region of Campos Novos, including several rare species, adds important data to the Scarabaeinae fauna in the central-western region of Santa Catarina. It may also help choosing priority areas for conservation in the region, where human impact, with large areas of monoculture, increasingly threatens the fragments of Mixed Ombrophilous Forest.

Trophic roles of scavenger beetles in relation to decomposition stages and seasons

Carcasses represent a trophic and reproductive resource or shelter for arthropods, which are a representative component of the decomposition process. Four experiments, one per season, were conducted in a semi-rural area of Bahía Blanca, Argentina, to study the trophic roles of cadaveric beetles, evaluating the abundance, composition and dominance during all decomposition stages and seasons. Species of necrophagous, necrophilous and omnivorous habits were found. Abundance, composition and dominance of beetles in relation to their trophic roles changed according to seasons and decomposition stages. Guilds and patterns of succession were established in relation to those periods. Trophic roles could be an indicator of beetle associations with decomposition stages and seasons.

New records of Sarcophagidae species (Diptera) with forensic potential in Rio de Janeiro

ABSTRACTSarcophagidae species are frequent and abundant in the decomposition process of corpses and, consequently, play an important role as a tool for the application of Forensic Entomology. Helicobia pilifera Lopes, 1939, Microcerella erythropyga (Lopes, 1936), Oxysarcodexia fringidea Curran & Walley, 1934 and Peckia (Peckia) pexata(Wulp, 1895) were recorded for the first time in a Forensic Entomology experiment in Rio de Janeiro, using domestic pig carcasses as substrate.

Reduction of the bull: cow ratio in the Brazilian Pantanal

This work was conducted to study alternatives for reduction of the bull:cow ratio in the Brazilian lowland and, therefore, lower the production costs for the local beef cattle industry. The ratios 1:10, 1:25, and 1:40 were used in native pastures with a mean stocking rate of 0.27 mature animal unit per hectare over two consecutive breeding seasons. Statistical analysis did not show any effect (P>0.05) of year (P = 0.2097), animal category (P = 0.0773), bull:cow ratio (0.8134) on reproductive performance. However, the pregnancy rate in a multiple bull system was higher (P = 0.0228) than in the individual bull system. An evaluation of the economic impact of this management system in the extensive Lowland herds showed that at the ratio of 1:10 the bulls were sub utilized.

Mitochondrial DNA of Nellore and European x Nellore crossing cattle of high performance

The objective of this work was to evaluate, through a polymorphism in the ND5 gene of the bovine mitochondrial DNA, the frequency of Bos taurus indicus mtDNA individuals in a sample of Nellore purebred origin animals (n = 69) and crossbred animals originated from crosses of European sires and Nellore purebred origin females (n = 275). Only 2.26% (8/354) of the animals presented Bos taurus indicus mtDNA. The high frequency of Bos taurus taurus mtDNA in these animals can be a consequence of selection, once the animals studied are originated from selected lineages of high performance for meat production.

Community structures of soil animals and survival of land snails on an island of the Ogasawara Archipelago

On Chichijima, one of the Ogasawara (Bonin) Islands located in the Western Pacific Ocean, land snails have declined, the suggested cause being predation pressure by an invasive flatworm (Platydemus manokwari). Soil fauna were investigated in areas where the snail survives, and where it has become extinct. Much of the fauna, dominated by introduced earthworms and ants, was undiminished, however, one undescribed but endemic carabid (Badister sp.), which selectively feeds on land snails, was absent in snail-extinct areas. The invasive flatworm P. manokwari has been reported to feed also on the carcasses of earthworms, as well as on live snails, and is therefore expected to occur in most parts of Chichijima Island. Among other groups, the density of isopods (also dominated by exotic species) was very low, in comparison with the reported ones 30 years ago. Community structure is currently reflected by dominance of earthworms and ants, decline of endemic isopods, and a high frequency of introduced or alien species.