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Coronaviruses in avian species – review with focus on epidemiology and diagnosis in wild birds Texto completo
2018
Miłek Justyna | Blicharz-Domańska Katarzyna
Coronaviruses in avian species – review with focus on epidemiology and diagnosis in wild birds Texto completo
2018
Miłek Justyna | Blicharz-Domańska Katarzyna
Coronaviruses (CoVs) are a large group of enveloped viruses with a single-strand RNA genome, which continuously circulate in mammals and birds and pose a threat to livestock, companion animals, and humans. CoVs harboured by avian species are classified to the genera gamma- and deltacoronaviruses. Within the gamma-CoVs the main representative is avian coronavirus, a taxonomic name which includes the highly contagious infectious bronchitis viruses (IBVs) in chickens and similar viruses infecting other domestic birds such as turkeys, guinea fowls, or quails. Additionally, IBVs have been detected in healthy wild birds, demonstrating that they may act as the vector between domestic and free-living birds. Moreover, CoVs other than IBVs, are identified in wild birds, which suggests that wild birds play a key role in the epidemiology of other gammaCoVs and deltaCoVs. Development of molecular techniques has significantly improved knowledge of the prevalence of CoVs in avian species. The methods adopted in monitoring studies of CoVs in different avian species are mainly based on detection of conservative regions within the viral replicase, nucleocapsid genes, and 3’UTR or 5’UTR. The purpose of this review is to summarise recent discoveries in the areas of epidemiology and diagnosis of CoVs in avian species and to understand the role of wild birds in the virus distribution.
Mostrar más [+] Menos [-]Coronaviruses in avian species – review with focus on epidemiology and diagnosis in wild birds Texto completo
2018
Miłek, Justyna | Blicharz-Domańska, Katarzyna
Coronaviruses (CoVs) are a large group of enveloped viruses with a single-strand RNA genome, which continuously circulate in mammals and birds and pose a threat to livestock, companion animals, and humans. CoVs harboured by avian species are classified to the genera gamma- and deltacoronaviruses. Within the gamma-CoVs the main representative is avian coronavirus, a taxonomic name which includes the highly contagious infectious bronchitis viruses (IBVs) in chickens and similar viruses infecting other domestic birds such as turkeys, guinea fowls, or quails. Additionally, IBVs have been detected in healthy wild birds, demonstrating that they may act as the vector between domestic and free-living birds. Moreover, CoVs other than IBVs, are identified in wild birds, which suggests that wild birds play a key role in the epidemiology of other gammaCoVs and deltaCoVs. Development of molecular techniques has significantly improved knowledge of the prevalence of CoVs in avian species. The methods adopted in monitoring studies of CoVs in different avian species are mainly based on detection of conservative regions within the viral replicase, nucleocapsid genes, and 3’UTR or 5’UTR. The purpose of this review is to summarise recent discoveries in the areas of epidemiology and diagnosis of CoVs in avian species and to understand the role of wild birds in the virus distribution.
Mostrar más [+] Menos [-]Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat Texto completo
2018
Różycki, Mirosław | Chmurzyńska, Ewa | Bilska-Zając, Ewa | Karamon, Jacek | Cencek, Tomasz
Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat Texto completo
2018
Różycki, Mirosław | Chmurzyńska, Ewa | Bilska-Zając, Ewa | Karamon, Jacek | Cencek, Tomasz
Health, religious, and commercial aspects justify the need for meat species identification. The lack of officially approved methods prompts the undertaking of research on validation of isoelectric focusing of proteins (IEF) for official purposes. Samples were prepared from pigs (Sus scrofa ferus domestica), cattle (Bos taurus), and poultry (Gallus gallus domesticus). Meat mixtures were made by blending 50%, 25%, 10%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.2% meat of other species. Samples were examined on ultrathin polyacrylamide gels with pH 3–9 gradient. The results of the study confirmed the stable and reproducible pattern of meat protein bands. The detection limit of raw meat admixtures from pigs, cattle, and poultry mostly ranged from 2% down to 0.2% (0.2% for poultry). However, the IEF method can be used to detect the addition of pig meat to bovine meat in an amount higher than 3%. At the significant mixture level (i.e at least 5% addition of meat of another species) IEF proves itself with 100% specificity, sensitivity, and accuracy. The achieved detection limits provide a basis for recommending the IEF method for routine tests in laboratories detecting the species origin of meat.
Mostrar más [+] Menos [-]Isoelectric focusing of proteins in the pH gradient as a tool for identification of species origin of raw meat Texto completo
2018
Różycki Mirosław | Chmurzyńska Ewa | Bilska-Zając Ewa | Karamon Jacek | Cencek Tomasz
Health, religious, and commercial aspects justify the need for meat species identification. The lack of officially approved methods prompts the undertaking of research on validation of isoelectric focusing of proteins (IEF) for official purposes.
Mostrar más [+] Menos [-]New insight of apparently healthy animals as a potential reservoir for Clostridium perfringens: a public health implication Texto completo
2018
Hamza, Dalia | Dorgham, Sohad M. | Elhariri, Mahmoud | Elhelw, Rehab | Ismael, Elshaimaa
New insight of apparently healthy animals as a potential reservoir for Clostridium perfringens: a public health implication Texto completo
2018
Hamza, Dalia | Dorgham, Sohad M. | Elhariri, Mahmoud | Elhelw, Rehab | Ismael, Elshaimaa
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.
Mostrar más [+] Menos [-]New insight of apparently healthy animals as a potential reservoir for Clostridium perfringens: a public health implication Texto completo
2018
Hamza Dalia | Dorgham Sohad M. | Elhariri Mahmoud | Elhelw Rehab | Ismael Elshaimaa
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.
Mostrar más [+] Menos [-]Effect of extender supplementation with low-molecular-weight antioxidants on selected quality parameters of cryopreserved canine spermatozoa Texto completo
2018
Lecewicz, Marek | Strzeżek, Rafał | Kordan, Władysław | Majewska, Anna
Effect of extender supplementation with low-molecular-weight antioxidants on selected quality parameters of cryopreserved canine spermatozoa Texto completo
2018
Lecewicz, Marek | Strzeżek, Rafał | Kordan, Władysław | Majewska, Anna
Introduction The addition of low-molecular-weight antioxidants during the freezing process improves post-thaw sperm quality. The high antioxidant potential of cryopreserved semen could have a positive effect on the motility, viability, and energy status of sperm cells and their ability to bind to the zona pellucida of oocytes. The aim of the study was to determine the effects of different concentrations and combinations of vitamins E and C in a semen extender on selected quality parameters of frozen-thawed canine spermatozoa. Material and Methods The experimental material was the semen of four mixed-breed dogs. Sperm viability (motility, plasma membrane integrity, and mitochondrial function) was examined at 0, 60, and 120 min in semen samples supplemented with the extender and in the controls. Results Combined supplementation with vitamins C + E at a concentration of 200 + 200 μM /1 × 10⁹ spermatozoa had the most profound effect on total sperm motility, linear motility, and the percentage of spermatozoa with intact plasma membrane and active mitochondria. Conclusion The synergistic activity of vitamins E and C had a more beneficial influence on the quality of frozen–thawed sperm than these non-enzymatic antioxidants applied separately.
Mostrar más [+] Menos [-]Effect of extender supplementation with low-molecular-weight antioxidants on selected quality parameters of cryopreserved canine spermatozoa Texto completo
2018
Lecewicz Marek | Strzeżek Rafał | Kordan Władysław | Majewska Anna
Introduction The addition of low-molecular-weight antioxidants during the freezing process improves post-thaw sperm quality. The high antioxidant potential of cryopreserved semen could have a positive effect on the motility, viability, and energy status of sperm cells and their ability to bind to the zona pellucida of oocytes. The aim of the study was to determine the effects of different concentrations and combinations of vitamins E and C in a semen extender on selected quality parameters of frozen-thawed canine spermatozoa.
Mostrar más [+] Menos [-]Determination of salicylic acid in feed using LC-MS/MS Texto completo
2018
Protasiuk, Edyta | Olejnik, Małgorzata
Determination of salicylic acid in feed using LC-MS/MS Texto completo
2018
Protasiuk, Edyta | Olejnik, Małgorzata
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.
Mostrar más [+] Menos [-]Determination of salicylic acid in feed using LC-MS/MS Texto completo
2018
Protasiuk Edyta | Olejnik Małgorzata
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.
Mostrar más [+] Menos [-]Dependence of sperm morphology and ejaculate characteristics on sperm concentration in the ejaculates of Hypor boars Texto completo
2018
Górski, Krzysztof | Kondracki, Stanisław | Wysokińska, Anna | Iwanina, Maria
Dependence of sperm morphology and ejaculate characteristics on sperm concentration in the ejaculates of Hypor boars Texto completo
2018
Górski, Krzysztof | Kondracki, Stanisław | Wysokińska, Anna | Iwanina, Maria
Determination of sperm concentration and morphology in ejaculate is essential in evaluating fertility. Sperm shape and dimensions may depend on their concentration in ejaculate. The aim of the study was to evaluate the dependence of Hypor boar morphological and morphometric sperm characteristics on concentration in ejaculate. The study was conducted on 120 ejaculates from 12 Hypor boars. Depending on sperm concentration, they were put into three groups: low, medium, and high. Ejaculate sperm concentration was determined with the photometric method. Slides were prepared from semen samples which were evaluated for the morphology of spermatozoa. The preparations for morphological analyses were by the eosin-gentian staining method. As the sperm concentration in the ejaculate increased, the length, perimeter, and area of the sperm heads also did. In the ejaculates with higher sperm concentration the sperm heads were rounder. The ratios of head dimensions to tail length or total length were the highest in the sperm from ejaculates with the highest concentrations. The highest percentage of morphologically abnormal sperm was noted in ejaculates with low concentrations. The dimensions and shape of sperm depend on the sperm concentration in the ejaculate. In ejaculates with the highest concentrations, the sperm have larger dimensions. Sperm concentration affects the frequency of morphological anomalies in the spermatozoa.
Mostrar más [+] Menos [-]Dependence of sperm morphology and ejaculate characteristics on sperm concentration in the ejaculates of Hypor boars Texto completo
2018
Górski Krzysztof | Kondracki Stanisław | Wysokińska Anna | Iwanina Maria
Determination of sperm concentration and morphology in ejaculate is essential in evaluating fertility. Sperm shape and dimensions may depend on their concentration in ejaculate. The aim of the study was to evaluate the dependence of Hypor boar morphological and morphometric sperm characteristics on concentration in ejaculate.
Mostrar más [+] Menos [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method Texto completo
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method Texto completo
2018
Kowalczyk, Ewelina | Kwiatek, Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed. PAs were extracted with 0.05 M sulphuric acid and purified with MCX cartridges. A solvent mixture consisting of ethyl acetate, methanol, acetonitrile, ammonia, and triethylamine (8:1:1:0.1:0.1, v/v) was used to wash alkaloids from the cartridges. After evaporation the residues were reconstituted in water and methanol mixture and subjected to LC–MS analysis. The developed method was validated according to SANTE/11945/2015 requirements. The recovery was from 80.6% to 114.5%. The repeatability ranged from 2.3% to 14.6%, and the reproducibility was from 4.9% to 17.7%. A new method for the determination of PAs in honey has been developed and validated. All evaluated parameters were in accordance with the SANTE/11945/2015 guidance document. Out of 50 analysed honey samples, 16 (32%) were positive for the content of at least one PA.
Mostrar más [+] Menos [-]Pyrrolizidine alkaloids in honey: determination with liquid chromatography-mass spectrometry method Texto completo
2018
Kowalczyk Ewelina | Kwiatek Krzysztof
Pyrrolizidine alkaloids (PAs) are probably the most widespread toxins of natural origin. More than 6,000 plant species produce these toxic compounds. Bees can forage on flowers of plants producing PAs, which leads to contamination of honey with the toxic compounds. To determine the contamination of honey with PAs, a sensitive method based on liquid chromatography coupled with mass spectrometry has been developed.
Mostrar más [+] Menos [-]GLP-1 localisation and proglucagon gene expression in healthy and diabetic mouse ileum Texto completo
2018
Taşçı, Serap Koral | Bingöl, Seyit Ali
GLP-1 localisation and proglucagon gene expression in healthy and diabetic mouse ileum Texto completo
2018
Taşçı, Serap Koral | Bingöl, Seyit Ali
Glucagon-like peptide-1 (GLP-1) is a polypeptide that is mainly produced by intestinal L cells and is encoded by the proglucagon gene. In this study, GLP-1 localisation was investigated in the ileum of healthy and diabetic mice by immunohistochemistry and proglucagon gene expression was assayed by reverse transcription-polymerase chain reaction. This study included 18 male Balb/c mice that were divided into diabetic, sham, and control groups. Mice in the diabetic group received 100 mg/kg of streptozotocin. Immunohistochemical expression of GLP-1 was determined using the avidin–biotin–peroxidase complex technique, and proglucagon gene expression was determined by RT-PCR. Analysis of GLP-1 immunohistochemical localisation showed that GLP-1-immunopositive cells (L cells) were present between epithelial cells in the intestinal crypts. The intensity and localisation of GLP-1 immunoreactivity were similar among the mice in all the groups. Proglucagon gene expression levels were also statistically similar among the mice in all the groups. No difference was demonstrated among the mice in the diabetic, sham, or control groups with respect to proglucagon gene expression and GLP-1 localisation in the ileum, suggesting that diabetes does not affect proglucagon gene expression in the ileum.
Mostrar más [+] Menos [-]GLP-1 localisation and proglucagon gene expression in healthy and diabetic mouse ileum Texto completo
2018
Taşçı Serap Koral | Bingöl Seyit Ali
Glucagon-like peptide-1 (GLP-1) is a polypeptide that is mainly produced by intestinal L cells and is encoded by the proglucagon gene. In this study, GLP-1 localisation was investigated in the ileum of healthy and diabetic mice by immunohistochemistry and proglucagon gene expression was assayed by reverse transcription-polymerase chain reaction.
Mostrar más [+] Menos [-]Effects of newly developed synbiotic and commercial probiotic products on the haematological indices, serum cytokines, acute phase proteins concentration, and serum immunoglobulins amount in sows and growing pigs – a pilot study Texto completo
2018
Czyżewska-Dors, Ewelina | Kwit, Krzysztof | Stasiak, Ewelina | Rachubik, Jarosław | Śliżewska, Katarzyna | Pomorska-Mól, Małgorzata
Effects of newly developed synbiotic and commercial probiotic products on the haematological indices, serum cytokines, acute phase proteins concentration, and serum immunoglobulins amount in sows and growing pigs – a pilot study Texto completo
2018
Czyżewska-Dors, Ewelina | Kwit, Krzysztof | Stasiak, Ewelina | Rachubik, Jarosław | Śliżewska, Katarzyna | Pomorska-Mól, Małgorzata
The aim of the study was to determine the effects of supplementation of sows’ and growing pigs’ diets with three newly developed synbiotic and two extant commercial probiotic products on selected immune parameters under field conditions. The study was performed on 30 sows and 48 piglets of the Danbred breed. Immune parameters such as concentration and proportion of white blood cells and their subpopulations, immunoglobulins amount in serum, and serum concentration of cytokines and acute phase proteins were recorded with the use of a haematology analyser and ELISA kits. No significant differences between treatment groups and controls were found with regard to the immune parameters evaluated except for serum immunoglobulin concentration, which was significantly increased by synbiotic products B and C and probiotic product D. The results of the study indicate that the synbiotic products B and C and probiotic product D are worthy of further investigation as promising candidates to improve the immune status of healthy sows and their offspring.
Mostrar más [+] Menos [-]Effects of newly developed synbiotic and commercial probiotic products on the haematological indices, serum cytokines, acute phase proteins concentration, and serum immunoglobulins amount in sows and growing pigs – a pilot study Texto completo
2018
Czyżewska-Dors Ewelina | Kwit Krzysztof | Stasiak Ewelina | Rachubik Jarosław | Śliżewska Katarzyna | Pomorska-Mól Małgorzata
The aim of the study was to determine the effects of supplementation of sows’ and growing pigs’ diets with three newly developed synbiotic and two extant commercial probiotic products on selected immune parameters under field conditions.
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