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Abstract

With a growing number of negative environmental burdens, several countries have increasingly begun to address the issue of environmental protection through a number of measures. Such measures include higher spending on public health, conservation of natural resources, less emission to the air, efficiency of waste sorting, reduction of water pollution, and groundwater. The contribution is based on the Environmental Performance Index (EPI) values to perform a cluster analysis of selected countries - especially OECD (organisation for Economic Co-operation and Development) countries. The database needed for analysis is the EPI indicator for the years for 2008 to 2018. The result will be clusters that will include countries with similar results of the EPI indicators for the reference period. It will be important for us to track the position of the Slovak Republic in this analysis.

Abstract

The goal of the present research is to analyze parameters of a bundle of logs for various models of forwarders in the Pryazha division of forestry of the Republic of Karelia. The investigated parameters were mass and volume of a bundle of logs, stacking factor of the bundle and the number of wood assortments in the bundle. The following models of forwarders have been investigated: John Deere 1210E, John Deere 1110E, Ponsse Elk, Ponsse Wisent, Amkodor 2661-01, Rottne F13D, Rottne F15D, Rottne F18D. We estimated the parameters of bundles formed from spruce sawlog 6.1 m long and bundles formed from spruce pulpwood 4 m long. Data on stem forms from harvester recorders have been collected to assess the parameters of a bundle of logs. Parameters of bundles have been determined based on computer experiment. The experiment consists of the following steps: random selection of the stem from the database; simulation of the cut-to-length process; simulation of log stacking process; calculation of parameters of a bundle of logs. We found that parameters of bundles vary to a quite substantial extent. Average variability of a bundle of logs formed of 6.1 m long spruce sawlog is 4.5 t, variability of the volume is 5.8 m3, and variability of the number of wood assortments in a bundle is 49 pcs. For a bundle made up of 4 m long spruce pulpwood variability of mass is on average 2.8 t, that of volume – 2.09 m3, that of the number of wood assortments – 57 pc. The presented results can inform transportation of wood on cutting areas, planning timber harvesting, as well as development new logging machines.

Abstract

Introduction

Land application of manure that contains antibiotics and resistant bacteria may facilitate the establishment of an environmental reservoir of antibiotic-resistant microbes, promoting their dissemination into agricultural and natural habitats. The main objective of this study was to search for acquired antibiotic resistance determinants in the gut microbiota of wild boar populations living in natural habitats.

Material and Methods

Gastrointestinal samples of free-living wild boars were collected in the Zemplén Mountains in Hungary and were characterised by culture-based, metagenomic, and molecular microbiological methods. Bioinformatic analysis of the faecal microbiome of a hunted wild boar from Japan was used for comparative studies. Also, shotgun metagenomic sequencing data of two untreated sewage wastewater samples from North Pest (Hungary) from 2016 were analysed by bioinformatic methods. Minimum spanning tree diagrams for seven-gene MLST profiles of 104 E. coli strains isolated in Europe from wild boars and domestic pigs were generated in Enterobase.

Results

In the ileum of a diarrhoeic boar, a dominant E. coli O112ab:H2 strain with intermediate resistance to gentamicin, tobramycin, and amikacin was identified, displaying sequence type ST388 and harbouring the EAST1 toxin astA gene. Metagenomic analyses of the colon and rectum digesta revealed the presence of the tetQ, tetW, tetO, and mefA antibiotic resistance genes that were also detected in the gut microbiome of four other wild boars from the mountains. Furthermore, the tetQ and cfxA genes were identified in the faecal microbiome of a hunted wild boar from Japan.

Conclusion

The gastrointestinal microbiota of the free-living wild boars examined in this study carried acquired antibiotic resistance determinants that are highly prevalent among domestic livestock populations.

Abstract

Introduction

Quasiamidostomum fulicae (Rudolphi, 1819) Lomakin, 1991, is a species of which the systematic position is still unclear, and it is reported in the literature under many synonyms. In the present study, an attempt has been made at establishing the ultimate systematic position of Quasiamidostomum fulicae against the backdrop of selected Amidostomatinae species.

Material and Methods

The parasites were identified based on measurements of external and internal structures. Ecological analysis of Q. fulicae was carried out using the quantitative indices (frequency, prevalence, mean intensity, relative abundance, and dominance index). Statistical analyses (discriminant analysis) were performed on measurement data.

Results

The intestines of 77 coots were examined. They yielded a total of 398 parasites, including 67 identified as Q. fulicae. Both males and females were located in the muscular gizzard. The morphometric analysis of Q. fulicae in this study showed the dimensions of all the internal organs to be in agreement with measurements reported by other authors. The discriminant analysis, used to find the differences between the examined nematode species (Amidostomoides acutum, A. petrovi, A. monodon, Amidostomum anseris, and Quasiamidostomum fulicae), gave highly significant results (P < 0.0001) with respect to both males and females.

Conclusion

The results justify the separation of Q. fulicae from the genus Amidostomum.

Abstract

Organophosphate insecticides are known to inhibit the activity of enzyme acetylcholinesterase. They affect olfactory learning and memory formation in honeybees. These insecticides cause mushroom body inactivation in honeybees, but their influence on other brain regions involved in olfactory perception and memory is unknown. The goal of this study was to study the effects of organophosphate insecticide diazinon on carnolian honeybee (Apis mellifera carnica) acetylcholinesterase activity in the olfactory brain regions of antennal lobe, mushroom body and lateral procerebrum (lateral horn). The lamina, medulla and lobula of optic lobes were also analyzed. The level of acetylcholinesterase activity was visualized using the histochemical staining method. Densitometric analysis of histochemical signals indicated that diazinon inhibited acetylcholinesterase activity only in the lip of calyces of mushroom body, but not in other analyzed olfactory regions, antennal lobe and lateral procerebrum. The visual brain system optic lobes were also unaffected. This is in accordance with the literature reporting that mushroom body is the main brain center for olfactory learning and memory formation in honeybees.

Abstract

Hemolymph is the “blood” circulating in the entire insect body. Analysis of this fluid gives information about the condition of the insect. The most precise analyses are conducted on insects’ hemolymph suspended in 0.6% physiological saline (NaCl). Most current hemolymph extraction methods are either difficult or do not provide pure material, the contamination of collected insect “blood” can change results. This study aimed to develop a technique for extract hemolymph, both easy and without risk of contaminating derived material. The presented method is a modification of available ways to extract, store and transport hemolymph with the use of a glass capillary. For the development of this technique, adult worker honey bees (Apis mellifera L.) were used. The method required such basic equipment as a glass capillary, sterile tweezer, Eppendorf tube and physiological saline. The collected hemolymph were frozen and hence sent in a glass capillary to another laboratory for analysis.

Abstract

An alternative to natural food shortage for honeybees is the provision of supplements. The objective of this research was to develop a method with ideal conditions for the fermentation of a protein supplement for honeybees. The microorganisms used were Lactobacilli, Bifidobacteria and Saccharomyces and the inulin prebiotic. There was an increase in lactic acid and a decrease in pH over a five-day fermentation period. The amount of acid bacteria present was 108–109 CFU/g of supplement. In the first phase the temperature and the humidity had significantly affected the fermentation but the variables inulin and probiotic didn’t. In the second phase, the lower temperatures and higher humidity produced the best effects on the fermentative responses. It was concluded that an ideal environment with temperature, humidity, inulin and probiotics could be created which allowed the fermentation of the protein supplement in five days obtaining final product fermentative characteristics close to bee bread.

Abstract

Nowadays, cell cultures are a standard tool in animal biotechnology, but the problem with honeybees is the constant lack of appropriate cell lines to be used in in vitro research. Until the imperfections of bee tissue cultures are resolved, researchers have to conduct experiments on bees in laboratory cage tests (LCTs).

At the turn of the 21st century many new hazards for beekeeping appeared. An early recognized problem was the Colony Collapse Disorder and Honey Bee Depopulation Syndrome, which were associated with the harmfulness of pesticides and strictly linked with a decline in bee immunity. Such problems in LCTs were attempted to be resolved through research on the interactions between biostimulators and antiparasitic drugs. LCTs allow the relationship between the dose of a specific factor and its impact to be determined, which can be used in the establishment of reference values. Furthermore, LCTs may be a useful tool in understanding the function and role of bee gut flora.

Using the honeybee as an animal model is possible thanks to knowledge of the honeybee genome and bee biology and the similarity between some physiological and biochemical processes and those occurring in humans. So far, LCTs have been used to understand better human aging, learning and gene expression regulating. This is facilitated by the advanced development of medicine and molecular genetics, and in the future the use of honeybees may become a standard in biochemical or gerontological research.

Abstract

Introduction

Bovine tuberculosis, caused by M. bovis, is endemic in Mexico and has had a big impact on public health. Jalisco is considered to be an important dairy region in the country, accounting for approximately 19% of the total milk production. Within Jalisco, the region of Altos Sur holds the largest proportion of the cattle inventory of the state.

Material and Methods

To determine the frequency of bovine tuberculosis in Altos Sur, Jalisco, as well as M. bovis genetic diversity, sampling of tissue (lymph nodes, lungs, and liver) from Holstein cattle was performed in four abattoirs belonging to three municipalities of this region (Tepatitlán de Morelos, San Miguel el Alto, and Arandas). Spoligotyping and whole-genome sequencing were carried out to assess the genetic relationships of M. bovis strains circulating in this area, as well as a comparison to isolates from other places in Mexico.

Results

Prevalence was 15.06%, and distribution similar among the three municipalities. The most frequent spoligotypes were SB0673, SB121, and SB0145. Whole-genome sequencing revealed three main clades (I, II, III), but isolates did not show clustering by region.

Conclusion

Phylogenetic analysis suggested ongoing transmission between herds of the different regions, and no unique source of infection was determined. This hinders efforts under the national program for the control and eradication of the disease, so serious attention must be paid to rural regions such as Altos Sur in order to improve its success.

Abstract

Introduction

Leishmaniasis is a zoonotic disease which is caused by protozoan parasites of the genus Leishmania. Canids are the most important reservoir of the parasites; however, limited data are available on the species of Leishmania prevalent in these animals and their impact on human health. The objective of this study was to estimate the seroprevalence of leishmaniasis in dogs from an inter-Andean region of Colombia during July 2016–July 2017, and to describe the clinical and histopathological features of the disease.

Material and Methods

A total of 155 dogs were subjected to clinical examination and a serological test for detection of antibodies against Leishmania. Necropsy was carried out on positive animals and tissue samples were processed by routine histopathology.

Results

Altogether 19 dogs were positive in the serological test, establishing a 12% seroprevalence of Leishmania. Clinical examination and necropsy revealed exfoliative and ulcerative dermatitis with haemorrhagic borders on the ears, head, nose, and legs. Histopathology revealed severe multifocal dermatitis with abundant Leishmania amastigotes within the cytoplasm of phagocytic cells, depletion of lymphocytes in lymphoid tissues, interstitial pneumonia, and interstitial nephritis. Tissue samples were positive for Leishmania by PCR.

Conclusion

The macro- and microscopic changes correlated with the presence of Leishmania as established by serological test and PCR.