ABSTRACT:Human infections caused by pathogens transmi�ed from fish or the aquatic environment are quite common and depend on the season, patients' contact with fish and related environment, dietary habits and the immune system status of the exposed individual. They are o�en bacterial species facultatively pathogenic for both fish and human beings and may be isolated from fish without apparent symptoms of the disease. The infection source may be fish kept for both for food and as a hobby.

A total of 669 individual cow milk samples originating from asymptomatic cows from 16 dairy farms were examined for the presence of microorganisms with the potential to cause mastitis. Coagulase-negative staphylococci clearly predominated (53.5% positive samples) followed by streptococci and enterococci (both occurring in 16.1% samples). Among streptococci, so-called mastitis streptococci (S. uberis, S. dysgalactiae and S. agalactiae) prevailed (11.7% positive samples). Enterobacteriaceae were found in 10.0% samples, most of which (6.6% samples) were positive for Escherichia coli. Yeasts (mainly Candida spp.) were found in 8.2% samples. One of the major mastitis pathogens, Staphylococcus aureus subsp. aureus, was isolated from 9.0% of samples. S. aureus isolates were further characterised in terms of their capability to form biofilm, antimicrobial susceptibility and clonality (PFGE). All S. aureus isolates were capable of biofilm formation and were generally susceptible to the majority of tested antibiotics. The exception was ampicillin, resistance to which was observed in 27.7% isolates. Therefore, the relatively frequent occurrence of S. aureus could be attributed to persistent intramammary infections due to biofilm formation rather than low efficacy of particular antibiotics. PFGE analysis revealed clonal spread of certain S. aureus isolates within and between farms indicating that certain lineages of S. aureus mastitis strains are particularly successful.

Viruses cause many diseases in plants, animals, and humans. They are strict intracellular parasites with cellular specificity. Viral particles can be transmitted by different routes, such as contaminated food and water. People usually get infected orally, after ingestion of products contaminated during processing or subsequent handling or preparation. This review article is focused on the most severe foodborne viruses specific for humans, of the following genera: Norovirus, Enterovirus, Hepatovirus, Astrovirus, and some others. Methods for detecting viruses in food and strategies for preventing virus transmission via food are also discussed.

ABSTRACT:The aim of this study was to use high throughput sequencing of piglet faeces to investigate if the favourable effects of sodium humate (HNa) and zinc oxide (ZnO) in post-weaning diarrhoea (PWD) treatment are related to changes in the faecal microbiota. Twenty four piglets weaned at 28 days of age were divided into three groups with eight animals per pen: a control group without any treatment (Control), a group treated with 2500 mg ZnO (ZnO), and a group treated with 20 g sodium humate and 1700 mg ZnO (HNa + ZnO) per kg of diet. Piglets of all three groups were challenged with two enterotoxigenic Escherichia coli (ETEC) strains (ETEC/O149/F4/LT and ETEC/O147/F18/LT) on Day 4 post-weaning. As a result very intense and severe diarrhoea with high mortality developed in the ETEC-infected control group, while the ZnO and HNa + ZnO dietary treatments both protected piglets from clinical signs of diarrhoea, mortality and depression of growth performance. A higher relative abundance of Gammaproteobacteria represented mainly by genus Escherichia on Day 10 postweaning in faeces of the ETEC-infected control group in comparison with ZnO and HNa + ZnO was detected. On Day 21, the highest relative increase of beneficial lactobacilli was observed in the HNa + ZnO group. Correlation analysis showed a positive correlation of the ETEC-infected control with the genera Turicibacter, Clostridium, Campylobacter, Dehalobacterium, Desulfuvibrio, Paludibacter and a negative correlation with the genera Prevotella, Blautia, Faecalibacterium, Lactobacillus, and Coprococcus. The opposite correlations with these genera were observed in the supplemented groups, especially in the HNa + ZnO group. The results indicate that dietary supplementation with HNa and ZnO affects the microbial composition of faeces while maintaining good health condition and growth performance of ETEC-infected weaned pigs.

No abstract

ABSTRACT:The high prophylactic doses of ZnO commonly used to control post-weaning diarrhoea (PWD) in piglets have become an environmental problem. The possibility of partial replacement of ZnO by sodium humate (HNa) in PWD treatment was investigated in this study. Weaned piglets (32) were challenged with two enterotoxigenic E. coli strains (ETEC/O149/F4/LT and ETEC/O147/F18/LT) and allocated into four treatments maintained for three weeks: C (no supplementation); ZnO2.5 (2.5 g ZnO/kg diet); HNa + ZnO1.0; HNa + ZnO1.5; HNa + ZnO1.7 (20 g HNa and 1.0, 1.5 and 1.7 g ZnO/kg diet, respectively). The effects on incidence, severity and duration of diarrhoea, faecal shedding of total E. coli and both ETEC strains, growth rate and selected blood parameters were investigated. In contrast with ZnO2.5 and HNa + ZnO1.7, high daily diarrhoea scores, incidence and duration and mortality due to severe dehydration were seen in C, HNa + ZnO1.0 and HNa + ZnO1.5 groups. The administration of ZnO and HNa did not affect the faecal shedding of the challenged ETEC strains for eght days, even in clinically healthy piglets in ZnO2.5 and HNa + ZnO1.7 groups. Signs of growth depression were found in C; HNa + ZnO1.0 and HNa + ZnO1.5 groups during the first week. No difference in growth performance was observed in ZnO2.5 and HNa + ZnO1.7 piglets. Most of the selected biochemical and haematological parameters did not differ significantly among the treatments. However, a significantly higher serum Zn as a result of high dietary ZnO intake in the ZnO2.5 group compared to the control and HNa groups was detected. Significantly lower serum P in ZnO2.5; HNa + ZnO1.7 and HNa + ZnO1.0 groups compared to the control group was most likely induced by the increased Zn in serum. The results indicate the possibility of reducing the high pharmacological levels of ZnO in the prophylaxis of PWD through partial replacement with HNa. Such a treatment maintains the favourable prophylactic effect while lowering the Zn content in faeces.Keywords: humic; enterotoxigenic E. coli; faecal shedding; growth performance; blood chemistry List of abbreviations: ALP = alkaline phosphatase, ALT = alanine transaminase, ANOVA = analyses of variance, AST = aspartate aminotransferase, BWG = body weight gains, CFU = colony forming units, DDS = daily diarrhoea score, ETEC = enterotoxigenic Escherichia coli, FCR = feed conversion ratio, FI = feed intake, HNa = sodium humate, HS = humic substances, PWD = post-weaning diarrhoea

No abstract

ABSTRACT:The aim of this study was to investigate the effects of sodium humate (HNa), applied to feed or drinking water as a partial substitution for pharmacological doses of ZnO, on clinical, biochemical and haematological indicators of health status, oxidative stress and the serum fatty acid (FA) profile in weaned piglets. Weaned piglets (32) were allocated into four groups: Control = basal diet containing 110 mg ZnO/kg; ZnO 2.5 = pharmacological dose of ZnO (2.5 g ZnO/kg); ZnO 1.7 + HNa (f ) = 1.7 g ZnO and 20.0 g HNa/kg; ZnO 1.7 + HNa (w) = 1.7 g ZnO/kg and drinking water with 0.2% HNa. All ZnO treatments resulted in good performance and clinical health of piglets in contrast to Control, which contained three diarrhoeic piglets. Increased triacylglycerols in the ZnO 2.5 and ZnO 1.7 + HNa (w) groups in comparison with Control suggested increased energy metabolism after treatments. Neither total cholesterol, nor HDL and LDL were affected by treatments. Piglets treated with ZnO and HNa had (ZnO 1.7 + HNa (w)) or tended to have (ZnO 1.7 + HNa (f )) lower urea in serum. Significantly (in ZnO 2.5 and ZnO 1.7 + HNa (f )) or non-significantly (ZnO 1.7 + HNa (w)) higher haematocrit and haemoglobin levels were detected in the blood of treated piglets. Long-term ZnO 2.5 treatment significantly increased serum 8-iso-PGF 2α , the most reliable biomarker of oxidative stress. Partial substitution of ZnO by HNa positively affected the oxidative status of piglets as evidenced by significant (ZnO 1.7 + HNa (w)) or non-significant (ZnO 1.7 + HNa (f )) declines in serum 8-iso-PGF 2α . ZnO 2.5 treatment significantly decreased saturated (SFA), monounsaturated (MUFA) and n-3 polyunsaturated FA (PUFA) and increased PUFA n-6 and n-6/n-3 ratios in serum compared to Control. The synthesis of some physiologically significant long-chain PUFA (LC-PUFA), namely n-6 dihomo-γ-linolenic acid and n-3 eicosapentaenoic, docosapentaenoic was negatively affected by ZnO 2.5 treatment. Both ZnO 1.7 + HNa (f )/(w) treatments significantly increased the proportion of SFA and PUFA n-3 and decreased PUFA n-6 and n-6/n-3 ratios in comparison with ZnO 2.5 and the effect was more considerable in ZnO 1.7 + HNa (w). Most individual PUFA n-3 and n-6 as well as the n-6/n-3 ratio in both treatments were similar to Control. The results indicate that the partial substitution of ZnO by HNa can benefit performance and health of weaned piglets to a similar extent as a high pharmacological dose of ZnO, whereas it can decrease the oxidative stress induced by prolonged over-supplementation of ZnO. Additionally, such a treatment can eliminate the unfavourable effect of high ZnO doses on the n-6/n-3 ratio and the proportion of some physiologically significant LC-PUFA in serum. Generally, it can be concluded that the effects of feed and water HNa supplementation are similar, but are more pronounced when HNa is applied to drinking water.Keywords: humic substances; pig; lipid metabolism; eicosanoids; serum biochemistry; haematology; performance; GC/MS; LC/MS-MS List of ab...