Oligonucleotide DNA fingerprinting revealing polymorphism in Phaseolus lunatus L.

Digoxigenated synthetic oligonucleotides complementary tosimple repetitive DNA sequences were used to detect polymorphisms inPhaseolus lunatus L. (Lima bean)genotypes. Twenty two accessions, including wild and cultivatedrepresentatives of the Mesoamerican and Andean gene pools andintermediate forms were included in this study. It could be shownthat five repetitive motifs, namely (AAT)₅,(ATG)₅,(GACA)₄,(GATA)₄,(GGAT)₄, were able to give clear-cutbands when used as probes and to reveal high levels of variation. Thehighest resolving power was revealed by the(AAT)₅ probe, which was able to detect eveninter-individual polymorphisms. Therefore, oligonucleotidefingerprinting has proved to be a useful tool to analyse geneticdiversity in Lima bean. Phylogenetic reconstruction based onJACCARD's similarity index confirmed the existence of two majorgene pools and the presence of a minor group of genetically separatedintermediate genotypes.     

Heavy metals in recent sediments and bottom-fish under the influence of tanneries in South Brazil

Selected metals were evaluated in surface sediments from Cadeia and Feitoria Rivers (Brazil), potentially affected by tanneries. Statistical factor analysis of sediment data allowed the identification of critical} metals and priority areas for biological monitoring, i.e., chromium and mercury at the lower course of Feitoria River. Non-piscivorous bottom-fish from the species Rineloricaria cadeae (violinha) were collected at reference and contaminated sites. Chromium was undetected} in fish tissues, and mercury accumulated in individuals living in contact with contaminated deposits. Mercury contents in fish were below World Health Organization quality standard for human consumption (0.5 μg/g). The ratio of total mercury content in fish (wet weight) to sediment (dry weight, <63 μm) was 0.5 and 0.7 at reference and contaminated sites, respectively. A risk assessment based on hazard index showed that maximum consumption of fish from contaminated site by human population should be 32 g/day, while at reference site the allowable amount could reach 140 g/day.     

A note on the variation of phaseolin among common bean landraces collected in Eastern Asia

Summary Phaseolin seed protein was used as a marker to reveal the origin, Mesoamerican or Andean, of common bean (Phaseolus vulgaris) accessions cultivated in some countries (Korea, China, and Japan) of eastern Asia. Andean cultivars (T and C phaseolin patterns) are predominant in this geographical area. Introductions from Middle America, represented by cultivars with S phaseolin type, also occurred at lower rate. In all cases, genotypes with larger seeds have been favoured.     

Volatile fractions from three cultivars of Olea europaea L. collected in two different seasons

The chemical composition of the volatile fractions from leaves of three Olea europaea L. cultivars (Leccino, Frantoio, and Cipressino) harvested at two different times of the year were examined by GC and GC-MS. The results showed a high content of aliphatic aldehydes in the three cultivars during both harvesting periods and an increase of (E)-2-hexenal (an aldehyde with high antimicrobial properties) percentage from July to November.     

Influence of toltrazuril treatment on parasitological parameters and health performance of piglets in the field--an Austrian experience

Porcine coccidiosis caused by Isospora suis is one of the leading causes of neonatal diarrhea in suckling piglets. Currently the only registered drug for metaphylaxis is toltrazuril. To evaluate the effect of treatment on piglets from 7 Austrian farms without and 8 Austrian farms with toltrazuril application we examined oocyst excretion (including determination of oocysts per gram of feces; OPG), diarrhea (fecal score FS 1-4 with 3 and 4 being diarrhea), and general health (health score HS 1-4 with 3 and 4 describing poor health). Both groups included farms with different levels of hygiene. Samples from 265 litters without treatment, comprising 1588 individual samples, and 1548 samples from 258 treated litters were taken twice (around the 14th and the 21st day of life, respectively), examined by autofluorescence and, if positive, by McMaster counting. In both groups animals had less diarrhea and lower health scores during the second sampling but the treated piglets were always significantly healthier and had less diarrhea. The percentage of weaned piglets was higher in treated animals although this was not significant (p=0.052). In the first round of sampling 17.8% of the individual samples from untreated piglets were positive for oocysts (with a maximum prevalence on the 12-15th day of life) while in the treated piglets only 0.4% shed oocysts p<0.001). At the second sampling only 2.1% of the untreated animals and none of treated piglets excreted I. suis (p=0.083). Positive animals shed up to 8 × 10(3)OPG. There was an increased risk for infected piglets to develop diarrhea (odds ratio, OR 4.73) and poor health (OR 5.05) in untreated piglets, and poor hygiene without disinfection was identified as a risk factor for poor health (OR 1.90), diarrhea (OR 1.42) and oocyst excretion (OR 1.73). The risk of poor health (OR 2.89) and diarrhea (OR 1.44) was also increased for piglets under poor hygienic conditions receiving toltrazuril, so both metaphylaxis of coccidiosis and good hygiene are necessary to effectively control neonatal diarrhea. The costs of treatment are considerably lower than the estimated financial production losses. Therefore, treatment is recommended for farms where clinical coccidiosis is diagnosed.     

Campylobacter jejuni, Campylobacter coli, and cytolethal distending toxin (CDT) genes in common teals (Anas crecca)

To evaluate the presence of Campylobacter spp. and related cdt genes, cloacal swabs were collected from 70 common teals (Anas crecca) and analyzed by culture methods and polymerase chain reaction. In addition, C. jejuni were examined also for the presence of wlaN gene. This is believed to be the first report of Campylobacter spp. in common teal and our results confirm the very common occurrence of C. jejuni (n=40) and C. coli (n=13) in waterfowls. Furthermore, the cdt genes were frequently present in both C. jejuni and C. coli isolated. Moreover, seven C. jejuni isolates carried also the wlaN gene which is presumably involved in the expression of ganglioside mimics in Guillain-Barré syndrome.     

Interaction of curcumin and bixin with β-cyclodextrin: complexation methods, stability, and applications in food

This work aimed to compare methods for the formation of complexes of bixin and curcumin with β-cyclodextrin (β-CD) and to evaluate the stability of the complexes formed by these methods and their food applications. The stoichiometric relationship between curcumin and β-CD was 1:2 and that between bixin and β-CD was 1:1. Curcumin-β-CD and bixin-β-CD complexes formed by kneading, coprecipitation, and simple mixing were evaluated by differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), or nuclear magnetic resonance (NMR-H). For both curcumin and bixin, the best method of complexation was coprecipitation. Complexation of colorants with β-CD promoted an intensification of color and increased water solubility; however, stabilization in the presence of light occurred only for bixin. Application of curcumin-β-CD in cheese and yogurt and bixin-β-CD in the curd did not alter the initial characteristics of the products, which were sensorialy well accepted. Therefore, the complexation of these natural colorants with β-CD favors their use in low-fat foods, broadening the field of industrial application.     

Comparison of the Transport of Tetracycline-Resistant and Tetracycline-Susceptible Escherichia coli Isolated from Lake Michigan

It was recently reported that tetracycline could enhance the mobility of manure-derived Escherichia coli within saturated porous media (Walczak et al. (Water Research 45:1681-1690, 2011)). It was also shown, however, that E. coli from various sources could display marked variation in their mobility (Bolster et al. (Journal of Environmental Quality 35:1018-1025, 2009)). The focus of this research was to examine if the observed difference in the mobility of manure-derived tetracycline-resistant (tet(R)) and tetracycline-susceptible (tet(S)) E. coli strains was source-dependent. Specifically, E. coli were isolated from Lake Michigan, and the influence of tetracycline resistance on Lake Michigan-derived E. coli was investigated through column transport experiments. Additionally, a variety of cell morphology and surface properties were determined and related to the observed bacterial transport behavior. Our experimental results showed that, consistent with previous observations, the deposition rate coefficients of the tet(R)E. coli strain was ~20-100% higher than those of the tet(S)E. coli strain. The zeta potential of the tet(R)E. coli cells was ~25 mV more negative than the tet(S)E. coli cells. Because the surfaces of the E. coli cells and the quartz sands were negatively charged, the repulsive electrostatic double-layer interaction between the tet(R)E. coli cells and the quartz sands was stronger, and the mobility of the tet(R)E. coli cells in the sand packs was thus higher. The tet(R)E. coli cells were also more hydrophilic than the tet(S)E. coli cells. Results from migration to hydrocarbon phase (MATH) tests showed that about ~35% more tet(S)E. coli cells partitioned to the hydrocarbon phase. As it was previously shown that cell hydrophobicity could enhance the attachment of bacterial cells to quartz sand, the difference in cell hydrophobicity could also have contributed to the observed higher mobility of the tet(R)E. coli cells. The size of the tet(R) and tet(S)E. coli cells were similar, suggesting that the observed difference in their mobility was not size-related. Characterization of cell surface properties also showed that tet(R) and tetS E. coli cells differed slightly in cell-bound lipopolysaccharide contents and had distinct outer membrane protein profiles. Such difference could alter cell surface properties which in turn led to changes in cell mobility.     

Early Evidence of the Anticipatory Response of Plasma Catecholamine in Equine Exercise

Catecholamines seem to play a role in equine exercise physiology that is somewhat different from their role in human beings. In sport horses, a greater increase in plasma adrenaline (ADR) levels occurs in response to strenuous exercise as compared with human beings. However, it is not known whether this is true for breeds not specifically bred for sport. The aim of this study was to gather data on plasma catecholamine kinetics during exercise in a nonracing breed. We also attempted to evaluate the influence of the phases preceding the start of the exercise on the kinetics of these molecules. Four 2-year-old female Esperia ponies were made to perform a four-step exercise test on a treadmill. Blood samples were collected in the box (basal 1), in the treadmill room (basal 2), and at the conclusion of each step, using an automatic system. ADR and noradrenaline (NOR) levels were determined by high-pressure liquid chromatography. Results were analyzed using analysis of variance and the Student-Newman-Keuls test. As compared with basal 1, basal 2 showed a significant 19.6-fold increase for ADR and a 6.7-fold increase for NOR. The highest concentration was observed for both molecules at the end of the fourth step, with a significant 1.2-fold increase as compared with blood samples collected at basal 2 for ADR and a 2.4-fold increase for NOR. Therefore, in Esperia ponies, catecholamine showed a trend similar to that of Standardbreds and Thoroughbreds. The results reported in this study also revealed a marked increase in ADR in the phases preceding the beginning of physical activity. Therefore, the greater adrenergic activity in horses in response to exercise could be because of an anticipatory response.     

Natural Fasciola hepatica infection in nutria (Myocastor coypus) in Uruguay

Fascioliasis, the zoonotic disease caused by the trematode Fasciola hepatica, is expanding worldwide, with a 17 million people at risk. Rodents, often recognized as a major source of zoonotic diseases, are affected by F. hepatica, with some species playing important roles in the disease epidemiology. The case reported here in a nutria or kiyá (Myocastor coypus) is the first documented case of F. hepatica in this species in Uruguay. Parasitic burden and total egg production detected are markedly higher than reported previously for this species, confirming its potential role as an effective reservoir and disseminator of liver flukes. Although further research is needed, nutria should be considered when designing effective control programs for fascioliasis.