Feedstuffs as a vehicle of cattle exposure to Escherichia coli O157:H7 and Salmonella enterica

Feed has been reported as a vehicle for transmission of Salmonella enterica in cattle and several lines of evidence suggest that feed can be a vehicle for transmitting Escherichia coli O157:H7 as well. To show whether microbial contamination of feeds could contribute to the populations of S. enterica and E. coli O157:H7 on a farm, we compared isolates from feed samples to bovine fecal isolates from the same farm using pulsed-field gel electrophoresis (PFGE). Four of 2365 component feed samples (0.2%) and 1 of 226 feed mill samples (0.4%) were positive for E. coli O157:H7. Twenty of 2405 (0.8%) component feed samples and none of 226 feed mill samples were positive for Salmonella. PFGE profiles from E. coli O157:H7 isolated from a component feed sample closely resembled that from a fecal isolate collected later from the same farm, and a similar observation was made of a Salmonella Tyhpimurium isolate from component feed on another farm. There were indistinguishable PFGE profiles from component feed Salmonella Tyhpimurium DT104 isolates and fecal isolates from the same farm. These results provide evidence for a role of cattle feed in transmission of E. coli O157:H7; S. enterica; cattle-bacteria.     

Exploring the potential uses of <Emphasis Type="Italic">Vitis vinifera</Emphasis> L. leaves as raw material for textile dyeing without metal mordants

This paper explores the potential uses of the aqueous extract of Vitis vinifera L. leaves in dyeing linen and silk fabrics without a metal mordant. The focus will be on investigating the tinctorial potential of Vitis vinifera L. leaves and its dyeing properties. The anthocyanins amounts of leaves from different Vitis vinifera L. varieties were determined by the spectrophotometry method. The effect of the main dyeing parameters (pH of the dye bath, temperature, and dyeing duration) on the dyeing quality results has been studied. Tannic acid and pomegranate peel extract have been used as a natural mordant. Experimental results have shown that fastness properties of dyed fabrics ranged from average to very good.     

Effects of pesticide residues on ground-dwelling lycosid and micryphantid spiders in laboratory tests

The effects of residues of three commercial pesticides in common use in Europe against cereal pests, on two dominant spider species, a lycosid and a micryphantid, were evaluated in the laboratory. Insecticide assay methods for juvenile and adult hunting and adult web-building, ground-dwelling spiders are described. Results varied with different sprayed substrates and species. Fenvalerate was more toxic than other pesticides and had a longer residual effect on all spiders when tested on moistened sand than on filter paper. Endosulfan was of high initial toxicity on sand, but was more toxic on filter paper to both adults and juveniles ofPardosa spp. Pyrazophos was non-toxic to the spiders tested, regardless of substrate. In general, the lycosids were more affected by pesticides than web-building spiders because of their different life strategies. A sprayed sand substrate matched field conditions better as a method to test the effects of pesticides on ground-dwelling spiders.     

Genetic variation and evolutionary forces shaping Cucumber vein yellowing virus populations: risk of emergence of virulent isolates in Europe

The genetic variation and evolutionary mechanisms shaping Cucumber vein yellowing virus (CVYV) populations were investigated by analysis of nucleotide sequences coding for P1b, P1b/P3 and coat proteins (CP) from isolates collected in different countries. The complete genome sequence of isolate ISM from Israel was also determined and compared to those of isolates Jor from Jordan and ALM32 from Spain. This isolate had overall nucleotide identities of 94·23 and 94·96% with ALM32 and Jor, respectively. Nucleotide variation among isolates was not homogeneously distributed, with the 5′ half of the genome being more variable than the 3′ half. A Bayesian phylogenetic tree of the CP showed that CVYV isolates clustered into two main clades: isolates from the Middle East region (Lebanon, Israel and Jordan) clustered in both clades whereas the isolate from Tunisia clustered in clade I and the European isolates clustered as a homogeneous phylogroup in Clade II. A similar topology was observed for P1b but with incongruences with respect to the CP, suggesting genetic exchange among virus isolates, which were confirmed with recombination algorithms. The low genetic diversity within the European phylogroup with respect to the other isolates, neutralist tests and genetic differentiation analyses suggest that the Middle East region is the cradle of CVYV and that a unique virus introduction event occurred in Europe, where the virus spread rapidly. Taken together, these findings indicate a risk of emergence of virulent CVYV isolates in Europe either through migration from the Middle East or by genetic changes of the European isolates.     

Integrated mite management in apples in Israel: Augmentation of a beneficial mite and sensitivity of tetranychid and phytoseiid mites to pesticides

Augmentative releases of the phytoseiid miteTyphlodromus athiasae were evaluated during summer 1987 in an apple orchard designated to be maintained under an IPM (integrated pest management) regime. Evaluation for establishment and recovery 2 weeks after each release showed complete absence of the mite and high population density of the injurious tetranychid mites. It was suspected that pesticides that had been used to control key pests may have been the cause. Laboratory tests with the pesticides used showed that the insect growth regulators triflumuron and fenoxycarb and the fungicide triadimenol caused only slight mortality of the predacious mitesT. athiasae (0-12%) andPhytoseiulus persimilis (6–10%), but a highly significant reduction in fecundity. Four days after treatment a reduction of 94%, 74% and 100% in fecundity ofT. athiasae, and 2 days after treatment a reduction of 78%, 53% and 80% in fecundity ofP. persimilis was brought about by triflumuron, fenoxycarb and triadimenol, respectively. On the other hand, 4 days after treatment there was a 27%, 16% and 9% increase in fecundity of the phytophagous miteTetranychus cinnabarinus caused by triflumuron, fenoxycarb and triadimenol, respectively. Laboratory and field tests were carried out to evaluate 13 other pesticides as to their selectivity toT. athiasae. The compounds azinphos-methyl, penconazole, vamidothion and diflubenzuron were found to be relatively harmless to this beneficial mite and they replaced the materials mentioned above in the coming seasons in several orchards. This caused recovery in high density of the predacious mite, which allowed reduced application of acaricides and the achievement of integrated mite management.     

Effects of deoxynivalenol exposure time and contamination levels on rainbow trout

The trend toward using plant‐based ingredients in aquafeeds is set to intensify; however, mycotoxin contamination might be a challenge. Two diets, with deoxynivalenol (DON) levels of 1,166 μg/kg (1.1 DON) and 2,745 μg/kg (2.7 DON), were prepared for short‐term DON exposure (50 days). A third diet with a low DON level of 367 μg/kg (0.3 DON) was prepared for long‐term DON exposure (168 days). Ingestion of DON by trout during both short‐term/high‐dosage exposure (50 days; 1,166 μg/kg and 2,700 μg/kg DON) and long‐term/low‐dosage exposure (168 days; 367 μg/kg DON) impacted growth performance and, to a lesser extent, liver enzyme parameters (2.7 DON). Histopathology showed mild to moderate changes in the liver but not in the other sampled tissues (intestine and kidney). Despite these effects, short‐term exposure of rainbow trout to high doses of DON did not result in increased susceptibility to Yersinia ruckeri. In both the short‐ and long‐term studies, the effects of DON showed a high interindividual variability. The present study confirms that subclinical levels of mycotoxins affect rainbow trout. The effects of such low mycotoxin levels could be masked by other production challenges while still negatively affecting productivity.     

Hole‐in‐the‐head disease in discus fish,Symphysodon (Heckel, 1840): Is it a consequence of a dietary Ca/P imbalance?

Hole‐in‐the‐head (HITH) disease‐affected fish develop characteristic lesions in the skin above sensory pores of the head and the trunk. This study investigated whether an unfavourable Ca/P ratio in the diet could provoke lesions consistent with HITH disease in discus fish Symphysodon (Heckel, 1840) as a comparable condition to secondary hyperparathyroidism of tetrapod species. Two groups of five fish were fed a plain beef heart diet (Ca/P of 0.03), whereas two other groups were kept on commercial discus feed (Ca/P of 2.73). Each feeding group was submitted to two different water hardness regimes (35.66–71.39 mg/L CaCO₃ and 124.94–196.33 mg/L CaCO₃, respectively). All fish were observed for the development of the characteristic lesions for 16 weeks. At the end of the study, histological, bacteriological and parasitological examinations were conducted and plasma Ca, P and Mg values were determined. Diplomonad flagellates were detected in two fish. Isolated bacteria of all groups mostly belonged to Aeromonadales and Pseudomonadales. No significant difference of plasma mineral values between the groups was observed. Compared to the results of other authors, Ca stayed mainly in the range and P exceeded the reference values. Histological examinations did not indicate HITH disease, and no fish developed signs of the disease during the study. Clinical trial registration number GZ 68.205/0135‐WF/V/36/2014.     

Appraisal of a high protein distiller’s dried grain (DDG) in diets for European sea bass,Dicentrarchus labrax fingerlings on growth performance,haematological status and related gut histology

High protein distiller's dried grains (HP‐DDG) are co‐products of ethanol production that uses prefractionation technology. An 8‐week growth trial was conducted to investigate the effect of partial replacement of soybean meal (SBM) by three levels of HP‐DDG (30%, 40% and 50%) on growth performance, physiological parameters and histological changes of the intestine of European sea bass, Dicentrarchus labrax. The results indicated that an increased dietary level of HP‐DDG of more than 30% significantly increases growth performance and improved the FCR of sea bass. In addition, replacement of SBM by HP‐DDG enhanced feed intake efficiency and the health status of fish. Haematology and serum biochemistry (haemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs), packed cell volume (PCV %) and humeral immune parameters including total protein, albumin, globulin, cholesterol, lysozyme activity and total antioxidant capacity significantly increased with increase HP‐DDG inclusion levels. The findings of this study indicated that HP‐DDG is a good complementary protein source for inclusion aquaculture diets and levels above 30% as a replacement of SBM did not compromise growth performance and physiological parameters of sea bass while enhancing some important indices of health status in this species.     

Evaluation of lung pathology in Dirofilaria immitis-experimentally infected dogs treated with doxycycline or a combination of doxycycline and ivermectin before administration of melarsomine dihydrochloride

Adulticide therapy in heartworm (Dirofilaria immitis)-infected dogs can lead to thromboembolism, which can seriously compromise post-treatment health status. Lung pathology following adulticide therapy was evaluated in three groups of experimentally infected dogs. Group 1 was treated with doxycycline at 20 mg/kg per os once daily for 30 days post infection followed by an intramuscular injection of melarsomine dihydrochloride (2.5 mg/kg) at Week 12, followed 1 month later by two injections 24 h apart. Group 2 was treated as described for Group 1, with the addition of ivermectin at 6 mcg/kg given monthly per os for 24 weeks post-infection. Group 3 received melarsomine alone, as described above. All dogs were necropsied at Week 24 and lung pathology was evaluated. Lesion criteria included perivascular inflammation and endothelial proliferation. Lesions were scored by two independent pathologists who were blinded as to treatment. Results indicate that doxycycline treatment alone or combined with ivermectin had lower lesion scores than lungs from dogs who had received melarsomine alone. Dogs that received the combined doxycycline/ivermectin protocol and treated with adulticide showed less severe arterial lesions and the virtual absence of thrombi.