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Abstract

Introduction

Ovine interferon-tau (oIFN-τ) is a newly discovered type I interferon. This study used biochemical techniques to transform the oIFN-τ gene into Escherichia coli to obtain the mass and soluble expression of the recombinant protein.

Materials and Methods

First, total RNA was extracted from fresh sheep embryonic tissues with TRIzol reagent and then used as a template to reverse transcribe and amplify the mature oIFN-τ gene with RT-PCR. The amplified product was next digested with the HindIII and XhoI restriction enzymes and inserted into the pET-32a(+) vector to construct the prokaryotic expression plasmid. The corrected in-frame recombinant plasmid, pET-32a(+)-oIFN-τ, was transformed into E. coli Rosetta (DE3) competent cells. After induction with isopropyl-beta-D-thiogalactopyranoside (IPTG), the recombinant protein was detected in bacteria. Finally, the bacteria were lysed by sonication, and the recombinant protein was purified by nickel affinity chromatography and DEAE anion exchange chromatography.

Results

The protein was confirmed to be oIFN-τ, which mainly existed in the soluble lysate fraction, as proven by SDS-PAGE and Western blot assays.

Conclusion

Purified IFN-τ exists mostly in a soluble form, and its anti-vesicular stomatitis virus (VSV) activity reached 7.08×10(6)IU/mL.

Abstract

Introduction

Introduction of highly pathogenic avian influenza virus (HPAIV) into a country and its further spread may have a devastating impact on the poultry industry and lead to serious economic consequences. Various risk factors may increase the probability of HPAI outbreak occurrence but their relative influence is often difficult to determine. The study evaluates how the densities of selected poultry species and proximity to the areas inhabited by wild birds impacted HPAI outbreak occurrence during the recently reported epidemics in Poland.

Material and methods

The analysis was developed using these risk factors in the locations of affected and randomly chosen unaffected commercial farms. Generalised linear and non-linear models, specifically logistic regression, classification tree and random forest, were used to indicate the most relevant risk factors, to quantify their association with HPAI outbreak occurrence, and to develop a map depicting spatial risk distribution.

Results

The most important risk factors comprised the densities of turkeys, geese and ducks. The abundance of these species of poultry in an area increased the probability of HPAI occurrence, and their farming intensity in several areas of central, western, eastern and northern Poland put these areas at the highest risk.

Conclusion

The results may improve the targeting of active surveillance, strengthen biosecurity in the areas at risk and contribute to early detection of HPAI in outbreak reoccurrences.

Abstract

Introduction

The aim of our study was to optimise an existing staining procedure: haematoxylin-eosin saffron (HES). The method follows the classical haematoxylin and eosin protocol with the addition of a staining step using natural saffron to better identify the collagen fibres.

Material and Methods

The saffron solution was obtained by dissolving ground saffron stigmas in absolute alcohol. In order to test the HES method for its staining ability on four main types of collagen (I, II, III, and IV), specific tissues (skin, tooth, cartilage, aorta, spleen, and penis) were chosen.

Results

The procedure showed a sharp differentiation between muscle, stained red or pink, and connective tissue, stained bright yellow or orange.

Conclusion

HES allows the diagnosis of reticulin fibrosis undetected in HE and in previous saffron staining procedures. HES represents an advantageous alternative to HE staining giving highly reproducible results with high diagnostic value.

Abstract

Introduction

Turkey histomonosis poses a serious threat to poultry production due to the ban on the use of effective drugs. The aim of the study was to evaluate the influence of a phytoncidal feed supplement on the course of histomonosis. The preparation was also analysed for immunomodulatory properties.

Material and Methods

Clinical observations and production monitoring were conducted in a flock of turkeys with histomonosis from their 11th to 56th weeks of life which were treated with the adiCoxSOLPF soluble supplement in a dose of 2.5 mL/L water. Later the preparation was used in a preventive dose (1 mL/L). The influence on the immune system was evaluated in broiler turkeys having been given adiCoxSOLPF for 3 days in doses of 1 or 3 mL/L. The T and B lymphocyte percentages in turkey blood and spleen tissue were analysed with flow cytometry. ELISA was implemented to evaluate antibody titres after Ornithobacterium rhinotracheale vaccination, and biochemical analyses were performed to evaluate the supplement’s safety.

Results

AdiCoxSOLPF was found effective in therapy and prevention of histomonosis. Additionally, adiCoxSOLPF stimulated both humoral and cell-mediated immune mechanisms, without impairing the functions of internal organs. The treated turkeys also yielded better production results (eggs/hen, fertility, and hatchability).

Conclusion

AdiCoxSOLPF possesses immunomodulatory properties and it can be used successfully in the prevention and therapy of histomonosis in turkeys.

Abstract

Introduction

Globally, genetically modified (GM) crops were grown on 191.7 million hectares in 2018, which were mostly sown with soybean, maize, cotton, oilseed rape, and rice. The most popular traits introduced through genetic modification include herbicide and pest insect resistance. The aim of this study was to identify and quantify genetically modified soybean used in animal feed in Poland.

Material and methods

This research was based on the real-time PCR technique. All methods for GM soybean events were adopted from the EURL GMFF database of methods and previously verified to meet the minimum criteria of acceptance. Over 15 years of research, 665 samples were examined in total.

Results

The most common GM soybean event was MON40-3-2, tested for from the beginning of the investigation. Next, in decreasing order of frequency, were MON89788, MON87701, and A2704-12. In the majority of samples (606; 91%) GM soybeans were identified at a content level above the 0.9% GM content threshold for mandatory labelling. Only 59 soybean samples (9%) were identified as GM negative. GM negative results were mainly identified during the analyses in the last three years of the study, from 2017 to 2019.

Conclusion

Our data clearly indicate that the majority of soybean used in Poland for animal feeding was genetically modified.

Abstract

Introduction

Proper conformational arrangement of the E2 molecules of bovine viral diarrhoea-mucosal disease virus (BVD-MDV) is crucial to obtain an effective recombinant vaccine candidate against the disease. In this study, we characterised a new molecule composed of two distinct sequences of the E2 glycoprotein of BVD-MDV and the Fc fragment of human immunoglobulin (BVDE2Fc).

Materials and Methods

The chimaeric protein was expressed in mammalian cell lines of different species by adenoviral transduction and purified by immobilised metal-affinity chromatography. The N-glycans were profiled by HPLC, and the BVDE2Fc immunogenicity was assessed in male mice. The antigen-antibody reactions were evaluated by ELISA.

Results

The MDBK cell line was selected from among five for the final production of BVDE2Fc. After purification to over 90%, the N-glycan profile showed neutral and complex oligosaccharides. The mouse immunisation induced a strong humoral response, which produced antibodies able to attach to conformational epitopes on E2 molecules, while the Fc fragment barely contributed to the immune response. Additionally, BVDE2Fc attached to antibodies from bovine sera positive to distinct BVD-MDV subtypes, whereas the loss of BVDE2Fc structure during the deglycosylation process considerably diminished those interactions.

Conclusion

These results demonstrate that the structure of E2 molecules arranged in tandem and attached to an Fc fragment could represent a viable design for future vaccine candidates against BVD-MD.

Abstract

Introduction

While the current tools to assess canine postoperative pain using physiological and behavioural parameters are reliable, an objective method such as the parasympathetic tone activity (PTA) index could improve postoperative care. The aim of the study was to determine the utility of the PTA index in assessing postoperative analgaesia.

Material and Methods

Thirty healthy bitches of different breeds were randomly allocated into three groups for analgaesic treatment: the paracetamol group (GPARAC, n = 10) received 15 mg/kg b.w., the carprofen group (GCARP, n = 10) 4 mg/kg b.w., and the meloxicam group (GMELOX, n = 10) 0.2 mg/kg b.w. for 48 h after surgery. GPARAC was medicated orally every 8 h, while GCARP and GMELOX were medicated intravenously every 24 h. The PTA index was used to measure the analgaesia–nociception balance 1 h before surgery (baseline), and at 1, 2, 4, 6, 8, 12, 16, 20, 24, 36, and 48 h after, at which times evaluation on the University of Melbourne Pain Scale (UMPS) was made.

Results

The baseline PTA index was 65 ± 8 for GPARAC, 65 ± 7 for GCARP, and 62 ± 5 for GMELOX. Postoperatively, it was 65 ± 9 for GPARAC, 63 ± 8 for GCARP, and 65 ± 8 for GMELOX. No statistically significant difference existed between baseline values or between values directly after treatments (P = 0.99 and P = 0.97, respectively). The PTA index showed a sensitivity of 40%, specificity of 98.46% and a negative predictive value of 99.07%.

Conclusion

Our findings suggest that the PTA index measures comfort and postoperative analgaesia objectively, since it showed a clinical relationship with the UMPS.

Abstract

Introduction

Foot-and-mouth disease is a highly infectious viral disease affecting all cloven-footed domestic animals. The three foot-and-mouth disease virus (FMDV) serotypes A, O and SAT2 are at present the greatest threat to susceptible animals in Egypt. The aim of the present study was, for the host factors associated with different FMDV infections in cattle during the acute phase, to compare these factors’ influence on the expression of the IL-10, TLR-2, TNF-α, CXCL10, CD48, NFATC4 and IFNG inflammatory and immune-related genes.

Materials and methods

Vesicular fluid and epithelium samples were obtained from at least three infected cattle on the same affected farm during three different FMDV outbreaks and were used for serotyping of the virus and for expression analysis of host genes. A two-step RT-PCR was used for diagnosis of the virus with primers specific for each serotype.

Results

In quantitative PCR analysis, the expression patterns of TLR-2 and IFNG were prominent, while NFATC4 expression was absent in all FMDV-infected cattle. The highest expression of CD48 was associated with increased expression of other inflammatory and immune-related genes (IL-10, TLR-2, TNF-α and IFNG), which may be an indication of rapid virus clearance.

Conclusion

The use of vesicular fluid and epithelium for investigation of viral and immune-related gene expression levels in acute FMDV infection is possible. Host-dependent variation in the expression of the studied genes was observed in different FMDV serotype outbreaks.

Abstract

Rift Valley fever (RVF) is a zoonotic, vector-borne infectious disease of ruminants and camels transmitted mainly by the Aedes and Culex mosquito species. Contact with the blood or organs of infected animals may infect humans. Its etiological factor is the Rift Valley fever virus (RVFV) of the Phlebovirus genus and Bunyaviridae family. Sheep and goats are most susceptible to infection and newborns and young individuals endure the most severe disease course. High abortion rates and infant mortality are typical for RVF; its clinical signs are high fever, lymphadenitis, nasal and ocular secretions and vomiting. Conventional diagnosis is done by the detection of specific IgM or IgG antibodies and RVFV nucleic acids and by virus isolation. Inactivated and live-attenuated vaccines obtained from virulent RVFV isolates are available for livestock. RVF is endemic in sub-Saharan Africa and the Arabian Peninsula, but in the last two decades, it was also reported in other African regions. Seropositive animals were detected in Turkey, Tunisia and Libya. The wide distribution of competent vectors in non-endemic areas coupled with global climate change threaten to spread RVF transboundarily. The EFSA considers the movement of infected animals and vectors to be other plausible pathways of RVF introduction into Europe. A very low risk both of introduction of the virus through an infected animal or vector and of establishment of the virus, and a moderate risk of its transmission through these means was estimated for Poland. The risk of these specific modes of disease introduction into Europe is rated as very low, but surveillance and response capabilities and cooperation with the proximal endemic regions are recommended.

Abstract

Introduction

The most frequently isolated bacteria in Polish aquaculture are of the Aeromonas genus; also pathogenic to human fish consumers, they cause substantial economic losses, and require antibiotic therapy to treat. Antibiotic residues in animal-derived food provoke concern. The aim of the study was to appraise the antimicrobial activity of ethanolic extracts of Ficus plant species against Aeromonas strains.

Material and Methods

Leaves of 41 Ficus species were collected from two Ukrainian botanic gardens. They were crushed, washed, homogenized in ethanol and centrifuged, and the supernatants were applied in the Kirby–Bauer disc-diffusion method to assess the susceptibility to them of Aeromonas hydrophila, A. sobria, and A. salmonicia subsp. salmonicida isolates confirmed as K886, K825, and St30 strains. Analogous assessment was also made of these bacteria’s susceptibility to sulfonamides, quinolones, tetracyclines, and one amphenicol. Data were analysed statistically.

Results

The majority of the extracts considerably inhibited bacterial growth, A. sobria being susceptible to 14 Ficus species, A. salmonicida subsp. salmonicida to 13, and A. hydrophila to 10.

Conclusion

Treatment with plant extracts has promise as an alternative to antibiotic therapy. Botanic gardens may offer new sources of plant-derived agents with a broad spectrum of biological and antimicrobial action. Further research will be useful to broaden knowledge of Ficus’ therapeutic potential.