Amitraz is a formamide exhibiting both acaricidal and insecticidal activity and is frequently used by beekeepers to protect honeybee colonies against Varroa destructor mites. The aim of this apiary trial was to evaluate the impact of honeybee colony fumigation with amitraz on the level of contamination of honey stored in combs.

Amitraz is a formamide exhibiting both acaricidal and insecticidal activity and is frequently used by beekeepers to protect honeybee colonies against Varroa destructor mites. The aim of this apiary trial was to evaluate the impact of honeybee colony fumigation with amitraz on the level of contamination of honey stored in combs. Experimental colonies were fumigated four times every four days with one tablet of Apiwarol per treatment. Honey was sampled from combs of brood chambers and combs of supers one day after each amitraz application and from harvested honey. Amitraz marker residues (as a total of amitraz and metabolites containing parts of molecules with properties specific to the 2,4-DMA group, expressed as amitraz) were evaluated in honey. All analysed samples were contaminated with amitraz metabolites. 2,4-DMA and DMPF were the most frequently determined compounds. The average concentration of amitraz marker residue in honey from groups where a smouldering tablet was located directly in beehives was significantly higher than that of residue in honey from groups with indirect smoke generation. No significant effect on the honey contamination deriving from the place where it was exposed to smoke (combs of brood chambers and supers) was noted. Amitraz marker residues exceeded the MRL in 10% of honey samples from combs. Fumigation of beehives with amitraz results in contamination of honey stored in combs.

Salicylic acid is a derivative of benzoic acid and occurs in nature. The main target of this study was to develop the liquid chromatography coupled with tandem mass spectrometry technique as a method for determination of salicylic acid in feed materials and compound feed.

Salicylic acid is a derivative of benzoic acid and occurs in nature. The main target of this study was to develop the liquid chromatography coupled with tandem mass spectrometry technique as a method for determination of salicylic acid in feed materials and compound feed. Salicylic acid was extracted from feed with 0.1% hydrochloric acid in methanol. Separation was achieved in 8 min in a gradient elution using 0.1% formic acid and acetonitrile. The analyte was detected using negative electrospray tandem mass spectrometry. The procedure was validated to the specifications of the European Commission Decision No. 2002/657/EC. The validation results showed the repeatability of the method, which was evaluated at three levels (0.25, 0.5, and 1.0 mg/kg). Calibration curves for the working ranges were linear (R² 0.9911 to 0.9936), and recoveries ranged from 98.3% to 101%. The LOD and LOQ for compound feed were 0.02 and 0.05 mg/kg, respectively. Salicylic acid was found mostly in corn, and its concentrations differed depending on whether it was young or fully grown (5.30–12.8 mg/kg and 0.13–1.01 mg/kg, respectively). A sensitive and reliable method for the determination of salicylic acid in feed and compound feed using LC-MS/MS was developed.

The aim of this study was examination of honey samples collected from apiaries situated in all Polish provinces for occurrence of Clostridium spp., especially C. perfringens.

The aim of this study was examination of honey samples collected from apiaries situated in all Polish provinces for occurrence of Clostridium spp., especially C. perfringens. The study was carried out on 240 honey samples (15 samples/province). Estimation of Clostridium titre, its cultures and C. perfringens isolate characterisation were performed according to the standard PN-R-64791:1994. A multiplex PCR method for detection of genes coding cpa (α toxin), cpb (β), cpb2 (β2), etx (ε), iap (ι), and cpe (enterotoxin) toxins was used. Clostridium spp. was noticed in 56% (136/240) of samples, and its titres ranged between 0.1 g and 0.001 g. Clostridium perfringens occurrence was evidenced in 27.5% (66/240) of samples. All isolates were classified to toxinotype A. Evidence of a high number of positive samples with occurrence of Clostridium spp. indicates a potential risk to consumers’ health. The infective number of Clostridium spp. is unknown; however, the obtained results have shown that a risk assessment on the entire honey harvesting process should be made in order to ensure microbiological safety. Moreover, a detailed study should be undertaken on the antibiotic resistance of C. perfringens isolates from honey samples.

Introduction:Clostridium perfringens is commonly found in the gastrointestinal tract of animals and humans and continues to cause one of the most prevalent foodborne diseases in man.

Introduction: Clostridium perfringens is commonly found in the gastrointestinal tract of animals and humans and continues to cause one of the most prevalent foodborne diseases in man. Material and Methods: A total of 355 samples were examined for the occurrence of C. perfringens: rectal swabs from cattle, sheep, and goats, fresh stool samples from diarrhoea sufferers having been in contact with these animals, irrigation water and soil samples from the husbandry sites, and preharvesting fresh produce from farms irrigated with the sampled water. All samples were collected from Cairo and Giza governorates, Egypt. PCR analysis was carried out with positive isolates using the α-toxin gene. Sequence analysis of the gene of C. perfringens isolates was performed using the neighbour-joining approach. Bootstrap analysis was executed with 1,000 resamplings. Results: 174 C. perfringens strains were isolated with a 49.01% prevalence. The highest prevalence of C. perfringens in apparently healthy animals was found in sheep (65.45%) followed by goats (58%), buffaloes (55%), and cattle (47.1%). Its prevalence in humans being in contact with these animals was 47.5%. The bacterium’s isolation from the soil and irrigation water was achieved in 40% and 31.7% of samples, respectively, posing a risk, particularly when the water and soil contact food in the field, shown by the fresh produce isolation of 40%. A significant relationship between the prevalence of C. perfringens in animal and environmental samples was identified (P < 0.05). A significant relationship was identified neither between animal species and C. perfringens prevalence, nor between the environmental source and C. perfringens prevalence (P > 0.05). All isolates were positive for the α-toxin gene by PCR. The sequence analysis and the phylogenetic relationship of the α-toxin genes from different samples revealed that C. perfringens from faeces of apparently healthy cattle, buffaloes, sheep, and goats is a significant threat in places where it can contaminate the soil and water. In addition, the sequence of C. perfringens from humans suffering from diarrhoea was found in the same cluster with the sequence from cows, goats, and sheep. Conclusion: The role of apparently healthy animals in transmitting C. perfringens to humans, either through being in direct or indirect contact via water or soil in the cultivation of vegetables and fruits, was demonstrated.

Nerium oleander is a plant of the Apocynaceae family toxic to humans, animals, and insects. This study was performed to determine the cardiac and neurotoxicity of the plant extract by oral administration in Wistar rats and Balb/c mice and to compare the susceptibility of these animal models to oleander toxicity.

Nerium oleander is a plant of the Apocynaceae family toxic to humans, animals, and insects. This study was performed to determine the cardiac and neurotoxicity of the plant extract by oral administration in Wistar rats and Balb/c mice and to compare the susceptibility of these animal models to oleander toxicity. Four groups of eight mice and eight rats received N. oleander extract orally while a fifth group was the control. Serum concentrations of the biochemical toxicity indicators, namely troponin and creatine kinase (CK), were determined and histopathological evaluation of the heart and brain was performed. In mice, CK and troponin concentrations were respectively 1.5 and 7 times higher than in the control group (P < 0.05), while in rats, they were 6–7 and 11 times higher. Hyperaemia, haemorrhage, and myofibrolysis, without infiltration of inflammatory cells, were observed in the heart. In the brain the authors observed hyperaemia associated with perivascular and perineuronal oedema, and in higher-dosed rats multifocal haemorrhagic and liquefactive necrotic lesions. Oleander can affect serum levels of CK and troponin due to nervous and cardiac injuries. Rats showed more severe changes in the biochemical indicators and histopathological lesions than mice. Therefore, biochemical and pathological findings indicate that Wistar rats are more susceptible to the cardiac toxicity and neurotoxicity effects of N. oleander poisoning than Balb/c mice.

The study was designed to investigate the effects of repeated lipopolysaccharide (LPS) treatment on growth performance, lymphoid organ indexes, and blood cells in Sprague-Dawley rats.

The study was designed to investigate the effects of repeated lipopolysaccharide (LPS) treatment on growth performance, lymphoid organ indexes, and blood cells in Sprague-Dawley rats. Forty healthy weaned Sprague-Dawley rats were randomly equally divided into LPS and control groups. Each rat in the LPS group was injected via the caudal vein with LPS (100 μg/kg b.w.) for 10 days, and the control group was treated with an equal volume of normal saline. On the 1ˢᵗ, 4ᵗʰ, 7ᵗʰ, and 10ᵗʰ days, growth performance, lymphoid organ indexes, and blood cells were evaluated in five necropsied rats. When rats were treated 3–10 times with LPS, their body weight and average daily gains increased more slowly than in the control group (P < 0.05). Repeated LPS treatment significantly increased spleen weight and the ratio of spleen to body weight (P < 0.05). White blood cells, neutrophils, and neutrophil percentage increased (P < 0.05) remarkably, but lymphocyte percentage, haemoglobin, and blood platelet counts decreased significantly (P < 0.05). LPS treatment obviously suppresses growth and promotes peripheral immune organ proliferation. It is indicated that host protective mechanism can be activated by multiple small doses of LPS and prevents organs from further damage during stress status.

Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines.

Dengue is one of the major emerging viral diseases in the world, with dramatic increases in reported cases in the last few decades and annual worldwide occurrence of approximately 390 million infections. It is a highly important mosquito-vectored disease and is a problem in tropical and subtropical areas of the world. The major aim of this study was to clone and express the dengue NS3 gene, in service to its therapeutic importance for the development of stable cell lines. Blood samples from dengue fever (DF) patients were collected and subjected to PCR amplification of the NS3 gene of dengue virus serotype-2 (DENV-2). The NS3 gene was amplified using gene specific primers and cloned in the TA cloning vectors. The gene was successfully expressed in mammalian expression vector pcDNA3.1. The current finding was different from a previously reported DENV-2 strain replicon constructed in different cells, in which the whole genetic material of the virus was used instead of an active protease gene, and which gave a low yield of replicon expressing cells. Recombinant NS3 could be used to produce an antibody that is possibly helpful for developing a single step diagnostic assay to detect the dengue virus NS3 antigen in sera of dengue patients.

Inosine pranobex (Isoprinosine) stimulates cell-mediated immune responses to viral infections in humans and might have also therapeutic use in animals. The aim of this study was to compare three in vitro cytotoxicity assays on mouse embryo fibroblasts and liver cancer cells and determine their ability to detect early cytotoxic effects for inosine pranobex.

Inosine pranobex (Isoprinosine) stimulates cell-mediated immune responses to viral infections in humans and might have also therapeutic use in animals. The aim of this study was to compare three in vitro cytotoxicity assays on mouse embryo fibroblasts and liver cancer cells and determine their ability to detect early cytotoxic effects for inosine pranobex. BALB/3T3 clone A31and HepG2 cells were incubated with inosine pranobex at concentrations from 0.1 to 1,000 μg/mL. Cell viability was determined with the MTT reduction, the LHD release, and the NRU tests. A decrease in the cell viability was observed after incubating the BALB/3T3 clone A31and HepG2 cells with inosine pranobex. Based on the cytotoxicity endpoints measured in these investigations in BALB/3T3 clone A31cells, it can be concluded that the cell membrane may be the first part of the cell to be affected by inosine pranobex. The disintegration of lysosomes and mitochondria follows mitochondria damage. In HepG2 cells likewise, the cell membrane may be the first part of the cell to be affected by inosine pranobex. Also in liver cancer cells, the disintegration of mitochondria (assessed with the MTT reduction assay) and next of lysosomes (assessed with the NRU assay) follows mitochondria damage.