Diet of the gracile mouse opossum (Gracilinanus microtarsus) (Didelphimorphia: Didelphidae) in a Brazilian cerrado: patterns of food consumption and intrapopulation variation

The diet of the gracile mouse opossum Gracilinanus microtarsus was studied in a cerrado remnant in south-eastern Brazil through the analysis of faeces sampled from adult individuals. Patterns of food resource consumption were assessed using the statistics of per cent occurrence. Intrapopulation variation in the number of food items detected in faeces as a function of relevant factors was inferred using generalized linear models. The latter statistical formalism also allowed variation in the number of food items detected in faeces to be interpreted in terms of rate ratios among levels of significant factors. Insects, spiders, snails and fruits were detected in the faeces of G. microtarsus , with insects, particularly termites, beetles and ants, being the most frequently detected food resource. These food resources were consumed in proportion to their relative abundance in the cerrado, suggesting that G . microtarsus is an opportunistic forager feeding primarily on insects. The generalized linear model identified sex, season and food resource as significant factors affecting the number of food items detected in faeces, as well as interactions between sex and season and season and food resource. Rate ratios calculated between sexes within seasons showed that the number of food items detected in the faeces of males was larger than that detected in the faeces of females in the warm-wet and cool-dry seasons. Rate ratios calculated between seasons within sexes showed different trends in the number of food items detected in faeces for each significant food resource. It is suggested that differences in the number of food items detected in faeces between sexes within season and between seasons within sexes are related to energetic requirements associated with reproduction.     

Summer food composition and food niche overlap of the raccoon dog, red fox and badger in Finland

Diets of raccoon dog, red fox and badger were studied in southern Finland from 1990 to 1996 by collecting faeces from dens and latrines during May-July of each year. The frequency of occurrence and relative volume of each food item in the faeces were calculated. The raccoon dog was the most and the red fox the least omnivorous of these carnivores, according to the diversity index. Diet composition of all these species varied among areas, indicating that they are opportunistic feeders. Mammals and birds constituted the bulk of the fox diet, while invertebrates, frogs and plants were most frequently eaten by the badger. The frequency of earthworms in badger faeces varied between 16 and 77%, according to area. Voles and shrews were important to the raccoon dog, but it also frequently consumed other food items. The food niches of the badger and the raccoon dog overlapped more than that of the red fox and other species. The red fox was more carnivorous and fed on larger prey items than the others, but the food composition of the red fox in the present study reflects the prey carried to the den for the pups; thus, the diet of adult foxes may be more similar to that of the raccoon dog. In conclusion, these 3 carnivores share many resources, suggesting that competition may occur among them: however, their diets also differ to some extent, which helps them to avoid competition. Furthermore, the badger and the raccoon dog are dormant during winter, when food is scarcest, which may be the reason why all these species can coexist in rather unproductive boreal forests.     

A model to predict the presence of longfin eels in some New Zealand streams, with particular reference to riparian vegetation and elevation

Two logistic regression models were developed from a database of 27 biotic and physicochemical variables for 99 sites in the Taieri River, New Zealand, to predict the probability of occurrence of longfin eels. Average depth was associated positively with eels while woody debris and oxygen concentration were negatively associated. At a macro-scale probability of eel occurrence declined with increasing elevation and, for a given elevation, was higher in tussock and pasture catchments and lower in pine and native forest settings. Using a separate fish database for the Taieri River this macro-scale model predicted eel presence 95·4% in agreement with observation. A map was generated from the model showing areas of predicted high, moderate and low probabilities of eel occurrence. The model also estimated the minimum total number of eels present in the Taieri River catchment (excluding lakes, and streams below 100 m and above 1000 m) as 20 865 (95% CL: 10 560-36 350).     

Resident,transient and uropathogenicE.coli strains in the intestinal tract of healthy and hospitalized adults

Samples of faeces were obtained at weekly intervals from 12 patients in a traumatology ward. Each time 20 colonies ofE.coli were typed. The results were compared with those of similar investigations in 10 healthy adults. No difference was found between the two groups as regards changes in the residentE. coli flora, nor in the frequency of occurrence of strains often associated with urinary tract infection.     

Birds in the diet of the Eurasian badger Meles meles: a review and meta-analysis

1. We reviewed 110 published studies of badger diet or badger predation of birds. The studies covered most of the Eurasian badger's range, from Ireland east to Japan and from Sweden south to southern Spain. 2. Bird remains were recorded in 2038 cases out of a total 36699 samples of badger faeces and stomachs. The overall percentage frequency of occurrence of bird remains in badger faeces and stomachs was 5.55% for all studies combined, and 7.97% for UK studies. The remains of 45 bird species from 11 orders were recorded. 3. The percentage frequency of occurrence of birds in badger diet increased significantly with latitude. There was no significant relationship between the occurrence of birds in badger diet and season. 4. While the prevalence of birds in the diet of badgers is generally low, the studies reviewed here provide insufficient evidence to assess whether badger predation has an impact on bird populations at a national scale, and experimental approaches to this problem are required.     

Progress report on the eel expedition of R.V. ‘Anton Dohrn’ and R.V. ‘Friedrich Heincke’ to the Sargasso Sea 1979

Synopsis This report presents preliminary results of the 1979 Sargasso Sea expedition from February to May 1979. Information is given on horizontal and vertical distribution of eel larvae and adults, adult eel tracking and pelagic trawling. Related matters such as electrophoretic studies on anguilliform larvae, feeding of eel larvae, predation on leptocephali, occurrence of other anguilliform larvae and hydrography are mentioned.     

The role of riverine forests for food supply for the omnivorous fish Brycon opalinus Cuvier, 1819 (Characidae) in the Serra do Mar, Southeast Brazil

The purpose of this study was to characterize the diet of the fish Brycon opalinus (Characidae) seasonally and locally, allowing for the determination of its food items and trophic relations with the aquatic and terrestrial environments. The study area encompasses three rivers (Paraibuna, Ipiranga and Grande) in the basin of the Paraibuna, southeast Brazil. Twelve monthly collections were made from January to December 2004. The degree of stomachic repletion and of accumulated visceral fat was analyzed, as was the intestinal length in each class of total length. The frequency of occurrence and the degree of food preference (DFP) of the food items of Brycon opalinus were determined by separating the vegetal and animal items, autochthonous and allochthonous, by insect order and vegetal family consumed. The frequency of occurrence of items of animal origin was found to be equivalent to that of vegetal origin, thus characterizing the omnivorism of Brycon opalinus feeding.     

The prevalence of Salmonella spp. in bovine faecal,rumen and carcass samples at a commercial abattoir

AIMS: To determine the prevalence, serotype and antibiotic resistance profile of Salmonella isolates in cattle and on carcasses at a commercial Irish abattoir. METHODS AND RESULTS: Faecal, rumen and carcass samples were collected from a beef abattoir over a 12-month period and examined for the presence of Salmonella spp. Isolates were serotyped, phage typed (when serotype was found to be S. Typhimurium) and tested for susceptibility to a panel of antibiotics. Salmonella was isolated from 2% of faecal, 2% of rumen and 7.6% of carcass samples. Salmonella was most frequently isolated from samples taken during the period August to October. S. Dublin was isolated from 72% of positive samples. S. Agona and S. Typhimurium definitive type (DT)104 were each isolated from 14% of positive samples. All S. Typhimurium DT104 isolates were resistant to ampicillin, chloramphenicol, streptomycin, sulphafurazole and tetracycline (ACSSuT). On occasion, from a single animal, the same serotype was isolated from more than one sample (i.e. faeces and rumen; faeces and carcass; rumen and carcass; faeces, rumen and carcass). CONCLUSIONS: Salmonella is present in cattle at slaughter and on beef carcasses at an Irish abattoir, with a higher frequency of occurrence during the period August to October. Most isolates from the study are not commonly associated with human clinical infection, with the exception of S. Typhimurium DT104 (R-type ACSSuT). SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides epidemiological data that is necessary for the understanding of beef as a source of human Salmonella infection.     

Gastrointestinal flora of cotton rats

The gastrointestinal (GI) flora of cotton rats was examined. No lactobacilli were detected in any part of the GI tract. Anaerobes, including Peptococcaceae, Bacteroidaceae, bifidobacteria and eubacteria, were the predominant bacteria in the stomach, small intestine, caecum and faeces. Aerobes and facultative anaerobes, including Enterobacteriaceae and streptococci, were detected at low numbers and very low frequency of occurrence in all parts of the GI tract. Sixty-one isolates of bifidobacteria were recovered from the stomach, small intestine, caecum and faeces of cotton rats. They were identified as Bifidobacterium animalis, B. pseudolongum biovar a and b. The study showed that the GI flora of cotton rats seem to be very different from the GI flora in other rodents.     

Assessing patterns of hybridization between North Atlantic eels using diagnostic single-nucleotide polymorphisms

The two North Atlantic eel species, the European eel (Anguilla anguilla) and the American eel (Anguilla rostrata), spawn in partial sympatry in the Sargasso Sea, providing ample opportunity to interbreed. In this study, we used a RAD (Restriction site Associated DNA) sequencing approach to identify species-specific diagnostic single-nucleotide polymorphisms (SNPs) and design a low-density array that combined with screening of a diagnostic mitochondrial DNA marker. Eels from Iceland (N=159) and from the neighboring Faroe Islands (N=29) were genotyped, along with 94 larvae (49 European and 45 American eel) collected in the Sargasso Sea. Our SNP survey showed that the majority of Icelandic eels are pure European eels but there is also an important contribution of individuals of admixed ancestry (10.7%). Although most of the hybrids were identified as F1 hybrids from European eel female × American eel male crosses, backcrosses were also detected, including a first-generation backcross (F1 hybrid × pure European eel) and three individuals identified as second-generation backcrosses originating from American eel × F1 hybrid backcrosses interbreeding with pure European eels. In comparison, no hybrids were observed in the Faroe Islands, the closest bodies of land to Iceland. It is possible that hybrids show an intermediate migratory behaviour between the two parental species that ultimately brings hybrid larvae to the shores of Iceland, situated roughly halfway between the Sargasso Sea and Europe. Only two hybrids were observed among Sargasso Sea larvae, both backcrosses, but no F1 hybrids, that points to temporal variation in the occurrence of hybridization.     

Feeding and movement of Anguilla australis and A. reinhardtii in Macleods Morass, Victoria, Australia

Feeding and movement of Anguitta australis Richardson, and A. reinhardtii Steindachner, were studied in Macleods Morass, Gippsland, Victoria from July 1975 to March 1977. Stomach fullness varied seasonally. Both species ingested a wide range of items with teleosts and insects forming the major group for A. australis and teleosts the major group for A. reinhardtii , which fed on a narrower range of items. No relationship between size of items ingested and size of eel was evident. Kendall rank correlation coefficients indicate that both intraspecific and interspecific differences in diets due to seasonal and size variations were usually insignificant.
Tagged eels were recaptured at the overall rate of 18·5 %; of 1051 eels released, a total of 194 eels was recaptured. Maximum linear distance travelled by two eels was 3715 m while maximum days at liberty was 643 days. Home range was in the order of 400m. No relationship between length of a tagged individual and days liberty or with distance moved was evident. Movement was closely related to fluctuations of water temperature with peaks being associated with feeding in the littoral zone of the Morass.     

Food habits of three carnivore species (Viverricula indica, Herpestes urva, and Melogale moschata) in Fushan Forest, northern Taiwan

The food habits and degrees of dietary overlap of lesser oriental civet ( Viverricula indica ), crab-eating mongoose ( Herpestes urva ), and ferret badger ( Melogale moschata ) inhabiting the Fushan Forest, northern Taiwan, were studied using faecal analysis between February 1993 and June 1994. Laboratory analysis of 154 civet faeces, and 174 mongoose faeces showed that both species fed on a wide variety of food items, including mammals, birds, reptiles, amphibians, fish, crustaceans, insects, oligochaetes, gastropods, chilopods, arachnids, and plants. Insects, oligochaetes, plants, and mammals were the four most important food items in the civets' diet, whereas crustaceans, insects, amphibians, and reptiles were the four most important food items consumed by mongooses. Amphibians were the only vertebrates, together with invertebrates and plants, found in the 64 ferret badger faeces we analysed, and oligochaetes, insects, and amphibians were the most important food items consumed by ferret badgers. The diversity of diet was highest in the mongoose, followed by the civet, and was lowest in the ferret badger.
The degree of dietary overlap was greatest between the civet and the ferret badger, followed by that of the civet and mongoose. The mongoose and ferret badger had the lowest degree of dietary overlap. However, the degree of dietary overlap varied in different seasons. Invertebrates were the most important food source for the carnivores in Fushan Forest.     

Recruitment of Anguilla spp. glass eels in the Waikato River,New Zealand. Evidence of declining migrations?

The timing of Anguilla spp. glass eel recruitment into the Waikato River, North Island, New Zealand, was studied over a 2 year period (2004–2005). While glass eels of both the shortfin eel Anguilla australis and the endemic longfin eel Anguilla dieffenbachii were caught, the former comprised >97% of the species composition. There was a positive correlation of glass eel migrations with spring tides, with peak migration periods typically occurring within a few hours of the peak of high tide, and between 2 and 4 days after the day of spring tide. Both water temperature and discharge had significant inverse relationships with glass eel catches, with temperature explaining >30% of the variance in catch periodicity. Comparison of catch data 30 years apart showed that main migration periods appear to occur several weeks earlier today than previously. Reduced catch per unit effort and duration of runs from recent years' sampling (compared with the 1970s) indicate that a reduction in recruitment may also have occurred during this period, something recorded in other temperate species of Anguilla .     

The autecology of the chub, Squalius cephalus (L.), of the River Lugg and the Afon Llynfi

(1) Seasonal variation in the intensity of feeding activity was demonstrated in two chub populations. Feeding activity was higher in summer and more pronounced in the young age-classes. The intensity of feeding activity was significantly correlated with temperature. (2) The diet of the total chub populations embraced a wide range of food items but vegetable material predominated. Substrate material was frequently encountered which suggested considerable feeding on the river bed. Fish were the most important animal food, by volume, in the River Lugg but Trichoptera larvae were most important in the Afon Llynfi. No remains of salmon parr or trout were found in chub stomachs but grayling were eaten. The most important prey fish, by volume, was the eel but cyprinids, especially minnows, were most important by frequency of occurrence. (3) Seasonal variation in the composition of the diet could be related to availability of food organisms but some selection was shown. Vegetable foods were most important in summer; animal foods, Trichoptera larvae in particular, were important in winter. (4) Analysis of the variation in the composition of the diet with age revealed several trends, notably a decrease in the importance of plant material, aquatic and aerial insects with age and a corresponding increase in the importance of larger prey foods such as fish, frogs and crayfish. (5) The commonly held view that chub are deleterious to salmonid stocks was examined. The absence of direct predation and the small likelihood of direct competition suggests that this view is incorrect.     

First report of the invasive eel pest Pseudodactylogyrus bini in North America and in wild American eels

We detected 2 species of monogenean gill worms, Pseudodactylogyrus bini (Kikuchi, 1929) Gusev, 1965 and P. anguillae (Yin & Sproston, 1948) Gusev, 1965 (Monopisthocotylea: Pseudodactylogyridae), on American eel Anguilla rostrata in 2 rivers in South Carolina, USA. One of these, P. anguillae, was reported 5 yr ago from Nova Scotia; as well as in South Carolina, we also discovered it in 2 localities in Chesapeake Bay. Differences in the morphologies of specimens of either species of worm from North America and northeastern Asia were negligible. Similarly, the level of variation in sequences in the ITS2 (internal transcribed spacers) region of ribosomal RNA was minor, and not consistent with geographical origin. These data indicate that these monogeneans invaded North America only recently, possibly in parallel with the nematode Anguillicola crassus (which is known to have been introduced with commercial imports of foreign eels). We map the current global occurrence of these monogeneans, and conclude that their dispersal from northeastern Asia was largely as a result of the eel trade, and has probably been secondarily augmented by longshore migration of infected eels, and possibly also by transport in ballast waters. With present technology, all eel stocks must still be collected from the wild; unless shipments are disinfected at quarantine, these and other eel pathogens (such as A. crassus) are likely to continue to colonise other regions of the world.     

F-specific RNA bacteriophages and sensitive host strains in faeces and wastewater of human and animal origin

Faeces of humans, pigs, cattle and chickens were investigated for the presence of somatic coliphages, F-specific bacteriophages and Escherichia coli strains sensitive to infection by F-specific phages. Attention was given to the possible effect of age and use of antibiotics on the prevalence of the FRNA phages and sensitive E. coli strains. Somatic coliphages were often detected in high numbers in all types of faeces. In contrast, FRNA phages were rarely detected in faeces from humans and cattle but more often in faeces from pigs and adult chickens. Samples from young chickens (with or without antibiotics) were consistently positive for FRNA phages (up to 3 x 10(6) pfu/g). F-specific RNA phages were found in substantial numbers (greater than 10(3) pfu/ml) in a variety of wastewaters: domestic, hospital, slaughterhouses and occasionally in 'grey water'. Their origin in wastewater was not clear. Strains from faeces usually belonged to serogroups I and IV. These types were also found in wastewater, as were group II and III strains. Serogroup II phages were abundant in wastewater of human origin but rare in faeces. Escherichia coli strains sensitive to infection by F-specific phages were common in faeces (overall 290/1081: 27%). No strains with fully depressed F-pilus synthesis were detected among the sensitive strains. It is concluded that the occurrence of F-specific RNA bacteriophages in water points to sewage pollution rather than faecal pollution; the mechanism of replication of these organisms in wastewater is not understood.     

F-specific RNA bacteriophages and sensitive host strains in faeces and wastewater of human and animal origin

Faeces of humans, pigs, cattle and chickens were investigated for the presence of somatic coliphages, F-specific bacteriophages and Escherichia coli strains sensitive to infection by F-specific phages. Attention was given to the possible effect of age and use of antibiotics on the prevalence of the FRNA phages and sensitive E . coli strains. Somatic coliphages were often detected in high numbers in all types of faeces. In contrast, FRNA phages were rarely detected in faeces from humans and cattle but more often in faeces from pigs and adult chickens. Samples from young chickens (with or without antibiotics) were consistently positive for FRNA phages (up to 3 × 10⁶ pfu/g). F-specific RNA phages were found in substantial numbers (> 10³ pfu/ml) in a variety of wastewaters: domestic, hospital, slaughterhouses and occasionally in 'grey water'. Their origin in wastewater was not clear. Strains from faeces usually belonged to serogroups I and IV. These types were also found in wastewater, as were group II and III strains. Serogroup II phages were abundant in wastewater of human origin but rare in faeces. Escherichia coli strains sensitive to infection by F-specific phages were common in faeces (overall 290/1081: 27%). No strains with fully derepressed F-pilus synthesis were detected among the sensitive strains. It is concluded that the occurrence of F-specific RNA bacteriophages in water points to sewage pollution rather than faecal pollution; the mechanism of replication of these organisms in wastewater is not understood.     

The diet of breeding Dippers Cinclus cinclus and their nestlings in the catchment of the River Wye, mid-Wales: a preliminary study by faecal analysis

A preliminary study by faecal analysis into the diet of seven pairs of breeding Dippers and their nestlings was undertaken in the catchment of the River Wye in spring 1983. Macro-invertebrate items in faeces could be identified to family and quantified on the basis of mouthparts whilst the macro-invertebrate prey available to each pair of Dippers was assessed quantitatively by riffle-sampling.
In terms of numerical abundance, ephemeropteran nymphs, particularly Baetidae, and trichopteran larvae, particularly Hydropsychidae, were more important to adults and nestlings, respectively. When prey weights were taken into account, trichopteran larvae were the most important macro-invertebrate group to both, but especially to nestlings.
Some macro-invertebrate groups were selected in proportion to their abundance in the environment although indices of electivity indicated that prey selection for adults and nestlings, respectively, was negatively and positively correlated with prey weight. Significant changes in diet were also apparent with nestling age: smaller items, such as ephemeropteran nymphs, were eaten by younger nestlings whilst larger items, such as trichopteran larvae, became more frequent up to Day 15 after hatching.     

Diet of brown-nosed coatis and crab-eating raccoons from a mosaic landscape with exotic plantations in southern Brazil

We described the diets of two procyonids, the brown-nosed coati Nasua nasua and the crab-eating raccoon Procyon cancrivorus, through analysis of stomach contents of road-killed specimens in southern Brazil. We compared them with previously published dietary information for another syntopic mesopredator, the crab-eating fox Cerdocyon thous. The landscape of the study area includes native grasslands, forests, exotic tree plantations, and other crops. Food items were represented by frequency of occurrence (FO) and relative volume (RV). Stomach contents of 23 coatis were analyzed. Animal and plant items were equally frequent, although the volume of plants was greater. Exotic plant species were consumed more than native plants. Among prey items, invertebrates were more important than vertebrates, mainly because of the frequency of coleopterans and annelids and the volume of necrophagous dipteran larvae. Five specimens of raccoons were analyzed, in which animal items had the highest FO and plant items had the highest RV. Both invertebrate and vertebrate prey had the same FO, although vertebrates had a higher RV. Our data suggest that these procyonids are opportunistic hypocarnivores, utilizing anthropic sources, with diet overlap. The coatis also overlapped their diet substantially with the foxes. The stomach-contents analysis revealed the importance of fruit pulp biomass, soft-bodied animals such as larvae, and also soil, which might indicate feeding habits such as scavenging and geophagy.