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Ecosystem services are an important aspect of grasslands utilization; however, they are often contradictory to their main purpose, which is a production of good quality and safe feed. In this study, we evaluated the difference between grass monocultures and species-rich mixtures in terms of epiphytic microflora and mycotoxin contamination levels. We hypothesized that higher species diversity would lead to higher microbial counts, which could lead to higher mycotoxin contamination risk. Differences in epiphytic fungal, yeast and total amount of microorganisms (CFU g -1) depending on the species diversity in the field has been evaluated by cultivation method. Concentration of deoxynivalenol (DON), zearalenone (ZEN) and aflatoxin B1 (AFB1) was measured by ELISA. Results are suggesting that higher total amount of microorganisms were found in monocultures, however, fungal and yeast counts were higher in species-rich mixtures. Higher species diversity of grasses was related to higher total microbial count (TMC) and yeast colonization of phyllosphere. Our results suggest higher risk of fungal phyllosphere colonization of species-rich mixtures with higher biodiversity and therefore higher risk of mycotoxin contamination of such feed., info:eu-repo/semantics/openAccess

With the rising interest in digestate use as a fertilizer on permanent cultures, there is a need to examine its effects on food and feed quality. This study is focused on the use of digestate in grassland fertilization and its effects on nutritive value parameters such as mycotoxin contamination (deoxynivalenol, aflatoxin, and T-2 toxin) and nutrient content (crude protein, crude fat, crude fiber, ash, nitrogen-free extract, digestibility of organic matter, acid detergent fiber, and ash-free neutral detergent fiber). The experiment was carried out in the Czech Republic, and the effects of fertilization regime, year, and harvest date (summer and fall cuts) on nutritive value were observed. An effect of the year on DON, AFB1, and T-2 contamination levels was observed. An effect of the harvest or fertilization regime on mycotoxin contamination was not observed. Significant differences were observed in the content of all nutrients, except ash, depending on the year. Differences were found only in the case of ADF levels, depending on the harvest date, as well; however, no differences were found between fertilization regimes. Our findings suggest that digestate does not negatively affect fodder in terms of nutritive value nor safety.

In this study, we reported the evaluation of ruminal parameters and the rate and degree of degradation of biogenic amines (BA) in vitro, using ruminal fluid from sheep fed two different diets (meadow hay and silage of Medicago sativa L.). Herein, the Charolais sheep breed with a ruminal cannula was used to gather samples. Multiple rumen parameters were evaluated after 10 days of the feeding period. Samples were processed using fermenters inoculated by BA (histamine, tyramine, putrescine, cadaverine, spermine, and spermidine) during 8-h fermentation. Levels of BA were determined using ion-exchange chromatography, and volatile fatty acids (VFA) were determined using gas chromatography. More rapid BA degradation was noticed in hay than in haylage. Overall, VFA levels increased with duration of the fermentation, while pH lowered. The rapid increase was observed after 4 h of fermentation. Ammonia concentration had a decreasing trend in silage and increasing in the hay. Hypotheses on BA degradation were accepted. Important knowledge of the development of ruminal parameters in time was obtained, and based on gathered information, it is possible to say that other parameters and their impacts on BA in rumen need to be examined further.

Sorghum is a forage species important in animal nutrition with an increased potential in the upcoming difficulties in agricultural practices in regard to climate change. Therefore, this paper describes its yield and nutritional parameters depending on growing conditions simulated on two locations (humid and fertile Obora, less fertile and dry Písky), two sowing dates (29. 5. and 25. 6.), and variety (11 varieties). Fresh matter yield was determined by weighing the sample on the field immediately after harvest, Dry matter yield and nutritional content were determined in laboratory by Weende analysis from dried and homogenized samples. Nutritional parameters measured were crude fibre, fat, nitrogen and ash content. Additionally, digestibility of organic as well as dry matter was determined. No significant differences in average fresh matter yield or dry matter yield were found between the two locations and sowing dates in general. There were significant differences among varieties, the highest yields were measured in KWS Zerberus (51.57 +- 3.76 t/ha of fresh matter yield, 15.98 +- 1.34 t/ha of dry matter yield, with higher values observed on Písky). Our data suggest, that sowing date does significantly affect fat content (higher in June sowing). Other nutritional parameters were also higher in sorghum sown in June, with the exception of ash. Nutritional composition of samples did not significantly differ variety to variety, however, there were differences in digestibility of the biomass. Organic matter digestibility was 70.58-85.67%, dry matter digestibility was 73.21-86.70%, with highest digestibility in DMS 45-480. Varieties with the highest importance to farmers in the area are KWS Zerberus, KWS Tarzan and KWS Kallisto (based on dry matter yield), and Triumfo BMR, Sweet Susana and DSM 45-480 (based on digestibility). Sorghum was able to perform well even on dry sandy soil with lower fertilization, which shows the high variability and suitability of sorghum in agric, info:eu-repo/semantics/openAccess

The present multi-centre study aimed at assessing the performance of air sampling as a novel method for monitoring Campylobacter in biosecured poultry farms. We compared, using a harmonized procedure, the bacteriological isolation protocol (ISO 10272-1:2017), and a real-time PCR method on air filter samples. Air samples and boot swabs were collected from 62 biosecured flocks from five European countries during the summer of 2019. For air filters, the frequency of PCR-positive findings was significantly higher (n=36; 58%) compared to the cultivation methods (P<0.01; Standardized Residuals). The cultivation protocols (one with Bolton enrichment and one with Preston enrichment) were comparable to each other, but returned fewer positive samples (0-8%). The association between type of sample and frequency of PCR-positive findings was statistically confirmed (P<0.01; Fisher's exact test), although no culture-positive air filters were detected using direct plating. For the boot swabs, the highest number of positive samples were detected after enrichment in Preston broth (n=23; 37%), followed by direct plating after homogenization in Preston (n=21; 34%) or Bolton (n=20; 32%). It is noteworthy that the Norwegian flocks, a country known to have low Campylobacter prevalence in biosecured chicken flocks, tested negative for Campylobacter using the new sensitive approach. In conclusion, air sampling combined with real-time PCR is proposed as a multi-purpose, low-cost and convenient screening method that can be up to four times faster and four times more sensitive than the current boot-swab testing scheme used for screening biosecured chicken production. Importance: Campylobacter bacteria are the cause of the vast majority of registered cases of foodborne illness in the industrialized world. In fact, the bacteria caused 246,571 registered cases of foodborne illness in 2018, which equate

The present pilot study aimed at evaluating air sampling as a novel method for monitoring Campylobacter in poultry farms. We compared the bacteriological isolation of Campylobacter from boot swabs and air filter samples using ISO 10272–1:2017. A secondary aim was to evaluate the use of molecular methods, i.e. real time PCR, on the same sample set. Samples from 44 flocks from five European countries were collected, and included air samples, in parallel with boot swabs. Campylobacter spp. was isolated from seven of 44 boot swabs from three of five partners using the enrichment method. Two of these positive boot swab samples had corresponding positive air samples. Using enrichment, one positive air sample was negative in the corresponding boot swabs, but Campylobacter spp. was isolated from direct plating of the boot swab sample. One partner isolated Campylobacter spp. from six of 10 boot swabs using direct plating. Overall, 33 air filter samples were screened directly with PCR, returning 14 positive results. In conclusion, there was a lack of correspondence between results from analysis of boot swabs and air filters using ISO 10272–1:2017. In contrast, the combination of air filters and direct real-time PCR might be a way forward. Despite the use of the detailed ISO protocols, there were still sections that could be interpreted differently among laboratories. Air sampling may turn into a multi-purpose and low-cost sampling method that may be integrated into self-monitoring programs.

The aim of the project was to evaluate the potential of microbial threat to feed safety in the year 2018. Analyses of the epiphytic community of several forage species (clovers, cocksfoot, fescue, festulolium, perennial ryegrass, timothy and trefoil) in variants of fertilized and non-fertilized vegetation were performed. The hypothesis is based on the fact that microorganisms are normally present on plant material during its growth all the way from the seed to the senescence; they are influenced by a plant's fitness, and they affect its harvest and utilization. Microflora was analyzed by cultivation on specific substrates, total microbial count and five specific microbial groups were observed and quantified. Forage species did not affect plant microflora. The highest risk factor of microbial contamination of feed was proved to be harvest date. Mycotoxin contamination of fresh feed was determined (deoxynivalenol and zearalenone) using ELISA. Zearalenone (ZEA) levels were negatively correlated to fertilization intensity, although these results were not statistically significant. Deoxynivalenol (DON) levels were the lowest in a moderate fertilization regime. Significant differences in mycotoxin content were found among botanical species., info:eu-repo/semantics/openAccess

Práce obsahuje zachycení celého technologického postupu při přípravě štočků digitální metodou, zjištění výhodnosti této metody, rešerši digitálních desek firmy BASF a DuPont, vliv potiskovaného materiálu na přírůstek., Dokončená práce s úspěšnou obhajobou