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Environmental contamination of free-range hen with dioxin
2021
Mikołajczyk, Szczepan | Pajurek, Marek | Warenik-Bany, Małgorzata | Maszewski, Sebastian
The transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) from a contaminated environment into the food chain is a serious consumer safety problem. As part of the Polish National Surveillance Program of PCDD/Fs and PCBs in food of animal origin, a concentration of PCDD/Fs of 4.61 ± 0.75 pg WHO-TEQ/g fat was determined in a sample of free-range eggs, which exceeded the permitted limit of 2.5 pg WHO-TEQ/g. The aim of the study was to investigate the source of the egg contamination and the risk for the eggs’ consumers. Eggs, muscles, feed and soil from the place where backyard waste burning had been carried out in the past and ash from a household stove tipped onto the paddock were analysed using the isotope dilution technique with high-resolution gas chromatography coupled with high-resolution mass spectrometry. The concentration in ash was low at 0.20 pg WHO-TEQ/g and the congener profile did not indicate the source of contamination. The dioxin content in soil from the backyard waste-burning site was 2.53 pg WHO-TEQ/g dry matter (d.m.) and the soil’s profile of PCDD/F congeners matched the profile of the contaminated eggs. By reason of the congener profile similarity, the investigation concluded, that the cause of the contamination was the backyard waste-burning site soil which the animals had access to. Frequent consumption of contaminated eggs from the analysed farm could pose a health risk due to chronic exposure, especially for vulnerable consumers.
显示更多 [+] 显示较少 [-]Coxiella burnetii DNA in milk, milk products, and fermented dairy products
2021
Valkovska, Linda | Mališevs, Artjoms | Kovaļenko, Kaspars | Bērzin̦š, Aivars | Grantiņa-Ieviņa, Lelde
Q fever in dairy cattle has been investigated in Latvia since 2012. In 2015, 10.7% of farms tested positive for the DNA of C. burnetii, its aetiological agent, in bulk tank milk. The presence of C. burnetii DNA and infectious bacteria in dairy products has been assessed in several countries, and because Latvian milk may contain them, parallel assessment in this country is recommended. Accordingly, the present study tested shop and farm retail dairy products from Latvia and included foreign products for comparison. Investigation was carried out of 187 samples of a diverse range of dairy products from 41 Latvian milk producers. Twenty-six comparable samples pooled from Estonia, France, Germany, Greece, Italy, Lithuania, the Netherlands, Poland and Spain were also included. The all-countries total number of fermented milk products was 160. Special attention was paid to products that could be more attractive to children because of their added chocolate, cacao, berry and fruit content. DNA was extracted and amplification of C. burnetii IS1111 was performed using a commercial PCR kit. Overall positivity was 60.56%. Domestic products were positive more often (60.96%) than foreign ones (57.69%). Only 26.67% of unpasteurised Latvian cow’s milk samples were positive whereas 76.47% of pasteurised equivalents and 63.13% of fermented milk products were. Sweetened and fruit-containing samples were 71.43% positive. The shedding of C. burnetii via milk should be monitored and only milk from healthy animals allowed for sale for direct human consumption without pasteurisation. Raw milk quality and the effectiveness of industrial heat treatment and pasteurisation methods in Latvia and other countries should be carefully assessed to ensure adequate consumer health protection.
显示更多 [+] 显示较少 [-]Molecular characterisation of the Mycobacterium bovis causing bovine tuberculosis outbreaks in Poland
2020
Krajewska-Wędzina, Monika | Kozińska, Monika | Radulski, Łukasz | Lipiec, Marek | Augustynowicz-Kopeć, Ewa | Weiner, Marcin | Szulowski, Krzysztof
Since 2009, Poland has been recognised as a country officially free of bovine tuberculosis (bTB), although in each year of the last five there were from 8 to 18 outbreaks of the disease. In 2008–2016, the largest number of cattle infected with bovine mycobacteria were eliminated in the Masovian Province (the central region of Poland) and the largest number of outbreaks of this zoonosis were recorded in this area. The close proximity of farms where bTB was found led to the suspicion that tuberculosis could have been transmitted between the affected herds. The aim of the study was the molecular characterisation of the pertinent M. bovis/caprae strains and determination of the epidemiological relationship of various bTB outbreaks. The material for microbiological tests came from 119 cattle (Bos taurus) from nine herds located in five provinces, neighbouring the Masovian Province. Laboratory tests of tissue material gave results confirming tuberculosis in 54 (45%) animals. All strains belonged to the Mycobacterium bovis species. A two-step analysis of genetic affinity allowed 50 strains to be identified as phylogenetically closely related and separated between three genetic clusters consisting of 2 to 27 strains. Based on the results of genotyping, bTB outbreaks were found in three herds, and three transmission chains were identified among these herds.
显示更多 [+] 显示较少 [-]Nutritional composition and heavy metal content in breast and thigh muscles of wild and intensively reared common pheasants (Phasianus colchicus)
2020
Flis, Marian | Grela, Eugeniusz R. | Żukowska, Grażyna | Gugała, Dariusz
Differing conditions in captive breeding and in the wild have impact on the mineral profile of the pheasant carcass and its heavy metal contents. This may be an indicator of environmental contamination. The study evaluated the nutritional composition and selected macro- and trace element contents (heavy metals in particular) in usable sections of pheasant breast and thigh muscles originating from captive breeding and wild birds. The tests were performed on the breast and thigh muscles of 20 wild and 20 farm bred birds from around Lublin, Poland, with equal sex representation. The nutrient and lead, cadmium, chromium, and nickel contents were determined using inductively-coupled plasma atomic emission spectroscopy. The farmed pheasants had a higher proportion of breast muscle. The thigh muscles of all birds had a higher fat content than the breast muscles (5.1 g vs. 3.4 g per kg of natural weight). The macroelement level depended on the muscle type and bird origin. The trace element content also did and gender dependence was also evident. The wild birds contained more cadmium in the breast muscles and lead in both muscles than the farm-raised ones. The high quality and usefulness of wild and farmed pheasant meat is confirmed. It has advantageous macro- and trace element contents and permissible heavy metal contents except for lead in wild birds. The heavy metal level can be a bioindicator of their environmental occurrence. In wild birds, the lead level may also reflect birdshot remnants.
显示更多 [+] 显示较少 [-]Leptospira interrogans serogroup Sejroe serovar Hardjo in aborting cows: two herd cases in Sicily (Italy)
2020
Grippi, Francesca | Giudice, Elisabetta | Pietro, Simona Di | Sciacca, Carmela | Santangelo, Francesco | Galluzzo, Paola | Barreca, Santino | Guercio, Annalisa
The aim of this study was to present two outbreaks of bovine abortion due to Leptospira infection in cattle herds located in the northern part of Sicily (Italy). The animals were positive for Leptospira interrogans serogroup Sejroe serovar Hardjo in a microscopic agglutination test (MAT). A total of 23 Charolaise cows (farm A) and 75 Limousine bulls and Cinisara and Modicana cows (farm B) were enrolled in this study. The blood samples were collected from all subjects at the following time points: before a cycle of intramuscular treatment with oxytetracycline dihydrate (T0), after 5–6 weeks from the treatment (T1), and every 10 weeks until seronegativisation (T2 in Farm A and T3 in Farm B). A serological test (MAT) was used for the diagnosis of leptospirosis. Two samples from farm A (2/23) and 29 samples from farm B (29/75) were positive to Leptospira interrogans, serogroup Sejroe, serovar Hardjo in the MAT. Leptospira spp. DNA was detected by real-time PCR in the urine sample of one positive cow on farm A, and in placenta and brain samples belonging to one aborted foetus on farm B. It is important to use serological and molecular diagnostic techniques complementarily to identify infected individuals.
显示更多 [+] 显示较少 [-]Prevalence and characterisation of class 1 and 2 integrons in multi-drug resistant Staphylococcus aureus isolates from pig farms in Chongqing, China
2020
Ye, Chao | Hou, Fengqing | Xu, Dongyi | Huang, Qingyuan | Chen, Xia | Zeng, Zheng | Peng, Yuanyi | Fang, Rendong
Integrons are mobile DNA elements that allow for acquisition and dissemination of antibiotic-resistance genes among pig farm-derived bacteria. Limited information is available on integrons of Staphylococcus aureus from pig farms. The aim of this study was to characterise and investigate the prevalence of class 1 and 2 integrons in multi-drug resistant (MDR) S. aureus isolates from pig farms. A total of 724 swabs were collected from 12 pig farms in Chongqing, China, and examined by conventional microbial and molecular methods. In total, 68 isolates were S. aureus, 57 of which were methicillin resistant (MRSA). All 68 isolates were MDR strains and carried integrons, of which 88.2% (60/68) harboured both class 1 and 2. In addition, 85.3% (58/68) of the class 2 integron-positive isolates carried the β-lactam resistance gene (blaTEM₋₁), and 66.7% (40/60) of the class 1 integron–positive isolates carried the aadA1c, aadA1 or dfrA1 gene for respective streptomycin and spectinomycin or trimethoprim resistance. Class 1 and 2 integrons are common among the pig farm-derived S. aureus isolates. On account of their significance for public health, the prevalence of the integrons and their associated resistance genes in pig farm-derived S. aureus isolates should be paid special attention.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Virulence factors and antibiotic resistance of avian pathogenic Escherichia coli in eastern China
2019
Xu, Xiaojing | Sun, Qing | Zhao, Lixiang
Avian pathogenicEscherichia coli (APEC) causes serious colibacillosis and significant economic losses. Data on profiles of virulence factors and antibiotic resistances among APEC strains are crucial to the control of infection. In this study, strains were isolated from eastern China, and the prevalence of virulence factors and distribution of antibiotic resistance were determined. APEC strains were isolated and characterised by PCR for O serogroups, virulence factor genes, antibiotic resistance, and phylogenetic groups. O78 was the most prevalent serogroup and type A was the most frequent phylogenetic group. ThefimH,feoB, andiron genes were the most prevalent among the isolates. All isolates were multiresistant, and all strains were resistant to ampicillin and tetracycline, which are widely used in the poultry industry in China. This study provided important data on the presence of virulence genes and antibiotic resistance profiles of APEC from poultry farms in eastern China.
显示更多 [+] 显示较少 [-]Experimental infection with T. canis and T. leonina in farm mink (Neovison vison)
2019
Klockiewicz, Maciej | Jakubowski, Tadeusz | Sobczak-Filipiak, Małgorzata | Bartosik, Justyna | Długosz, Ewa
Introduction: Farm mink (Neovison vison) can be naturally exposed to T. canis and T. leonina pathogens on the farm. If mink were hosts, it would imply some veterinary public health as well as animal welfare issues. For this reason, the aim of the study was to determine whether mink might be definitive or paratenic hosts of these parasites. Material and Methods: Four groups of mink were infected with both parasite species using larvated eggs or feed containing mouse tissue previously infected with the parasites. Following inoculation, the infections were monitored in vivo by faecal examination for 14 weeks p.i., and then western blotting and ELISA were performed. Results: Coprology did not reveal any canine roundworm eggs, neither were nematodes found in mink intestines during post mortem examination. The specific IgG antibodies recognising excretory/secretory (ES) antigens of both parasite species were identified in mink sera. Single T. leonina tissue larvae were found in digested organs. Conclusions: Our results confirm that farm mink may contribute both T. canis and T. leonina infections. It was proved that farm mink were not their definitive hosts, and therefore mink faeces need not be considered a source of canine roundworm eggs in any soil it fertilises. Nonetheless, as farm mink may be a paratenic host for both parasite species, this may have some impact on the health and welfare of infected animals.
显示更多 [+] 显示较少 [-]Characterisation of newly emerged isolates of classical swine fever virus in China, 2014–2015
2017
Leng, Chaoliang | Zhang, Hongliang | Kan, Yunchao | Yao, Lunguang | Li, Mingliang | Zhai, Hongyue | Li, Zhen | Liu, Chunxiao | Shi, Hongfei | Ji, Jun | Qiu, Reng | Tian, Zhijun
Introduction: In 2014–2015, the epidemic of classical swine fever (CSF) occurred in many large-scale pig farms in different provinces of China, and a subgenotype 2.1d of CSF virus (CSFV) was newly identified. Material and Methods: The phylogenetic relationship, genetic diversity, and epidemic status of the 2014–2015 CSFV isolates, 18 new CSFV isolates collected in 2015, and 43 other strains isolated in 2014–2015 were fully analysed, together with 163 CSFV reference isolates. Results: Fifty-two 2014–2015 isolates belonged to subgenotype 2.1d and nine other isolates belonged to subgenotype 2.1b. The two subgenotype isolates showed unique molecular characteristics. Furthermore, the 2.1d isolates were found to possibly diverge from 2.1b isolates. Conclusion: This study suggests that the Chinese CSFVs will remain pandemic.
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