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Non-antibiotic possibilities in prevention and treatment of calf diarrhoea
2020
Smulski, Sebastian | Turlewicz-Podbielska, Hanna | Wylandowska, Agata | Włodarek, Jan
Due to increasing bacterial antibiotic resistance and the consumers’ tendency to choose organic products, cattle farmers are interested in alternative methods of calf diarrhoea treatment. This is a major challenge for veterinarians. Few methods of non-antibiotic treatment that bring satisfactory results have been reported in the related literature so far. In this article, the authors compare different non-antibiotic methods of diarrhoea prevention and treatment in calves. Among the alternatives discussed are herbs, probiotics, prebiotics and synbiotics, lactoferrin, and bacteriophages. It was found that the best results could be achieved through the use of pro-, pre- and synbiotics. However, the authors would like to point out that with the expansion of knowledge about the practical use of broad-scale bacteriophages, they could be the best alternative to antibiotics.
Afficher plus [+] Moins [-]Effect of goose parvovirus and duck circovirus coinfection in ducks
2020
Liu, Jie | Yang, Xiaoxia | Hao, Xiaojing | Feng, Yongsheng | Zhang, Yuli | Cheng, Ziqiang
Coinfection of goose parvovirus (GPV) and duck circovirus (DuCV) occurs commonly in field cases of short beak and dwarfism syndrome (SBDS). However, whether there is synergism between the two viruses in replication and pathogenicity remains undetermined. We established a coinfection model of GPV and DuCV in Cherry Valley ducks. Tissue samples were examined histopathologically. The viral loads in tissues were detected by qPCR, and the distribution of the virus in tissues was detected by immunohistochemistry (IHC). Coinfection of GPV and DuCV significantly inhibited growth and development of ducks, and caused atrophy and pallor of the immune organs and necrosis of the liver. GPV and DuCV synergistically amplified pathogenicity in coinfected ducks. In the early stage of infection, viral loads of both pathogens in coinfected ducks were significantly lower than those in monoinfected ducks (P < 0.05). With the development of the infection process, GPV and DuCV loads in coinfected ducks were significantly higher than those in monoinfected ducks (P < 0.05). Extended viral distribution in the liver, kidney, duodenum, spleen, and bursa of Fabricius was consistent with the viral load increases in GPV and DuCV coinfected ducks. These results indicate that GPV and DuCV synergistically potentiate their replication and pathogenicity in coinfected ducks.
Afficher plus [+] Moins [-]Animal coronaviruses in the light of COVID-19
2020
Domańska-Blicharz, Katarzyna | Woźniakowski, Grzegorz | Konopka, Bogdan | Niemczuk, Krzysztof | Welz, Mirosław | Rola, Jerzy | Socha, Wojciech | Orłowska, Anna | Antas, Marta | Śmietanka, Krzysztof | Cuvelier-Mizak, Beata
Coronaviruses are extremely susceptible to genetic changes due to the characteristic features of the genome structure, life cycle and environmental pressure. Their remarkable variability means that they can infect many different species of animals and cause different disease symptoms. Moreover, in some situations, coronaviruses might be transmitted across species. Although they are commonly found in farm, companion and wild animals, causing clinical and sometimes serious signs resulting in significant economic losses, not all of them have been classified by the World Organization for Animal Health (OIE) as hazardous and included on the list of notifiable diseases. Currently, only three diseases caused by coronaviruses are on the OIE list of notifiable terrestrial and aquatic animal diseases. However, none of these three entails any administrative measures. The emergence of the SARS-CoV-2 infections that have caused the COVID-19 pandemic in humans has proved that the occurrence and variability of coronaviruses is highly underestimated in the animal reservoir and reminded us of the critical importance of the One Health approach. Therefore, domestic and wild animals should be intensively monitored, both to broaden our knowledge of the viruses circulating among them and to understand the mechanisms of the emergence of viruses of relevance to animal and human health.
Afficher plus [+] Moins [-]Association of oxidative stress biomarkers and clinical mastitis incidence in dairy cows during the periparturient period
2020
Laliotis, George P. | Koutsouli, Panagiota | Sotirakoglou, Kyriaki | Savoini, Giovanni | Politis, Ioannis
The aim of this study was to determine changes of reactive oxygen species (ROS), serum antioxidant capacity (SAC), oxidative stress index (OSi), and α-tocopherol (α-T) during the periparturient period in healthy and mastitic cows and to further investigate whether these parameters can be used as a tool for identifying cows at higher risk of developing mastitis. Blood samples from 110 dairy cows from two commercial farms were obtained at dry-off, calving, and 30 days post-partum. Healthy cows formed group A (n = 90) and mastitic cows B (n = 20). Blood serum was obtained by centrifugation, and the aforementioned parameters were determined. A general linear model was used for analysing the associations among the determined blood parameters, the health of the animals’ udder, and the sampling time. ROS and OSi values were higher (P < 0.001) by a respective 14% and 26%, and SAC values lower (P < 0.001) by 10% in group B than in group A at calving. ROC curve analysis revealed that all determined parameters at calving and α-T at dry-off and 30 days post-partum had excellent or acceptable predicting ability for mastitis incidence. This information provides a tool for early identification of cows at high risk of developing mastitis, allowing the implementation of intervention strategies.
Afficher plus [+] Moins [-]Genetic relationship of Salmonella isolates found in subcutaneous abscesses in leopard geckos (Eublepharis macularius)
2020
Zając, Magdalena | Maluta, Aleksandra | Wasyl, Dariusz | Skarżyńska, Magdalena | Lalak, Anna | Samcik, Ilona | Kwit, Renata | Szulowski, Krzysztof
The article describes the occurrence and phylogenetic relationship of Salmonella isolates found in subcutaneous abscesses of leopard geckos. The aim of the study was to determine the cause of the abscesses and to characterise isolated Salmonella strains. Samples of abscesses from five animals and internal organs (lungs, liver, and gut) of three of them were tested for Salmonella according to the PN-EN ISO 6579:2002/A1:2007 standard. The antimicrobial resistance was evaluated by minimal inhibitory concentrations and the genetic similarity of the isolates was assessed with pulsed field gel electrophoresis (PFGE). In total, seventeen Salmonella isolates belonging to five different serovars were found to be susceptible to all tested antimicrobials except streptomycin. The serovars were S. Hadar, S. Fluntern, S. Tennessee, S. enterica subsp. salamae 55:k:z₃₉, and S. Kentucky. Up to three serovars from different organs were isolated from the same individual. In two geckos, Salmonella were detected in the lungs. In three serovars, XbaI-PFGE typing revealed indistinguishable isolates from organs and abscesses. Multiple Salmonella serovars might be involved in abscess formation and infections. The occurrence of the same PFGE profiles of the isolates may testify to the role of opportunistic organisms in causing infection.
Afficher plus [+] Moins [-]Occurrence of Marek’s disease in Poland on the basis of diagnostic examination in 2015–2018
2020
Marek’s disease (MD) is a tumourous disease caused by Marek’s disease virus (MDV) and most commonly described in poultry. The aim of the study was to determine the occurrence of Marek’s disease virus infections in Poland and analyse clinical cases in the years 2015–2018. The birds for diagnostic examination originated from 71 poultry flocks of various types of production. Birds were subjected to anatomopathological examination post mortem, during which liver and spleen sections and other pathologically changed internal organs were taken. These sections were homogenised with generally accepted methods, then total DNA was isolated and amplified with a real-time PCR. A pair of primers complementary to the MDV genome region encoding the meq gene were used. MDV infection was found predominantly in broiler chicken flocks (69.01%), and also in layer breeder (9.85%) and commercial layer flocks (7.04% each). The results of research conducted in the years 2015–2018 clearly indicate that the problem of MDV infections is still current.
Afficher plus [+] Moins [-]Point-of-service diagnostic technology for detection of swine viral diseases
2020
Nannucci, Lapo | Barattini, Paolo | Bossis, Ioannis | Woźniakowski, Grzegorz | Balka, Gyula | Pugliese, Carolina
A research project is underway aiming to develop a field diagnostic tool for six important viruses of the pig sector, namely: African swine fever virus (ASFV), porcine reproductive and respiratory syndrome virus (PRRSV), swine influenza virus (SIV), porcine parvovirus (PPV), porcine circovirus (PCV2), and classical swine fever virus (CSFV). To obtain a preliminary sounding of the interest in this type of instrument among its potential operators, a questionnaire was drawn up and submitted to three categories of stakeholders: farmers, veterinarians, and others (including scientific and technical staff working on animal farms). Four countries participated: Italy, Greece, Hungary, and Poland. In total, 83 replies were collected and analysed in a breakdown by stakeholder type and pertinence, where the areas were the importance of the main diseases within the different countries, diagnostic tool operational issues, and economic issues. The main end-users of this kind of instrument are expected to be private veterinarians and pig producers. The infectious agents seeming to be most interesting to diagnose with the instrument are PRRSV, SIV, PPV, and PCV2. The most decisive parameters which have been selected by the stakeholders are sensitivity, cost, simplicity, and time required to obtain results. The economic issue analysis showed that the majority of those who would prefer to buy rather than rent the device are willing to pay up to €3,000 for a diagnostic field tool.
Afficher plus [+] Moins [-]A novel, rapid, and simple PMA-qPCR method for detection and counting of viable Brucella organisms
2020
Zhang, Shi-Jun | Wang, Lu-Lu | Lu, Shi-Ying | Hu, Pan | Li, Yan-Song | Zhang, Ying | Chang, Heng-Zhen | Zhai, Fei-Fei | Liu, Zeng-Shan | Li, Zhao-Hui | Ren, Hong-Lin
The plate counting method widely used at present to discern viable from non-viable Brucella in the host or cell is time-consuming and laborious. Therefore, it is necessary to establish a rapid, simple method for detecting and counting viable Brucella organisms. Using propidium monoazide (PMA) to inhibit amplification of DNA from dead Brucella, a novel, rapid PMA-quantitative PCR (PMA-qPCR) detection method for counting viable Brucella was established. The standard recombinant plasmid with the target BCSP31 gene fragment inserted was constructed for drawing a standard curve. The reaction conditions were optimised, and the sensitivity, specificity, and repeatability were analysed. The optimal exposure time and working concentration of PMA were 10 min and 15 μg/mL, respectively. The correlation coefficient (R²) of the standard curve was 0.999. The sensitivity of the method was 10³ CFU/mL, moreover, its specificity and repeatability also met the requirements. The concentration of B. suis measured by the PMA-qPCR did not differ significantly from that measured by the plate counting method, and the concentrations of viable bacteria in infected cells determined by the two methods were of the same order of magnitude. In this study, a rapid and simple PMA-qPCR counting method for viable Brucella was established, which will facilitate related research.
Afficher plus [+] Moins [-]Potential determinants of Clostridium spp. occurrence in Polish silage
2020
Goldsztejn, Magdalena | Grenda, Tomasz | Kozieł, Nina | Sapała, Magdalena | Mazur, Małgorzata | Sieradzki, Zbigniew | Król, Beata | Kwiatek, Krzysztof
Silage quality deteriorates with Clostridium spp. contamination, and if consumed, such silage jeopardises herd health and productivity. Minimising its occurrence reduces economic and animal welfare risks. The study investigated the influence of environmental and technological determinants on the Clostridium genus’ occurrence in silage. Analyses were conducted on 305 silage samples directly collected from farms located in all Polish provinces. Cultures and isolates were evaluated phenotypically and examined for occurrence of Clostridium spp., particularly C. perfringens and C. botulinum using PCR techniques. The results were statistically analysed using the ᵡ² test for continuous and Student’s t-test for non-continuous values. The most influential effect on Clostridium spp. occurrence is exerted by factors potentially associated with primary production, like the type of fertilisation and the contamination level of the ensiled feed material. Clostridium spp. was detected in 232 (76%) samples, and C. perfringens strains, predominantly toxinotype A, in 79 (26%). C. botulinum occurrence was not detected. Deterioration of silage by clostridia could be prevented by a properly conducted ensiling process with the addition of starter cultures, but the presence of spores mainly depends on primary production and the extent of contamination of the feed material.
Afficher plus [+] Moins [-]Effect of bathing in a 0.1% aqueous solution of ethacridine lactate on selected physiological parameters of Cornu aspersum Müller edible snails
2020
Ziętek, Jerzy | Dzięgiel, Beata | Wójcik, Alicja | Wilczyńska, Anna | Adaszek, Łukasz | Winiarczyk, Stanisław
The prohibition of antibiotic use in edible snails obligates breeders to treat bacterial infections by different means, of which a common one is a bath in Gram-positive– and partially Gram-negative–bactericidal ethacridine lactate solution. The aim of the study was to determine the effect of bathing Cornu aspersum Müller snails in a 0.1% aqueous solution of ethacridine lactate on selected physiological parameters of haemolymph. The study included 80 snails, divided into two equal groups (study and control). The study group was subjected to bathing in ethacridine lactate and the control group to bathing in tap water. Both groups were treated daily for seven days. The number of haemocytes in the haemolymph, the activity of alanine (ALT) and aspartate (AST) aminotransferases, and the concentration of urea were determined. In the study group, after exposure to ethacridine lactate solution an increase in ALT activity, changes in the De Ritis ratio, an increase in the amount of haemocytes, and a decrease in body weight were found. No such changes were detected in the control group snails or in animals after the first bath. Multiple applications of a 0.1% ethacridine lactate bath may adversely affect Cornu aspersum Müller snails.
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