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Characterisation of Yersinia enterocolitica strains isolated from wildlife in the northwestern Italian Alps
2022
Carella, Emanuele | Romano, Angelo | Domenis, Lorenzo | Robetto, Serena | Spedicato, Raffaella | Guidetti, Cristina | Pitti, Monica | Orusa, Riccardo
Yersiniosis is a zoonosis causing gastroenteritis, diarrhoea, and occasionally reactive arthritis and septicaemia. Cases are often linked to meat consumption and the most common aetiological agent is the Gram-negative bacilliform Yersinia enterocolitica bacterium. The occurrence of Yersinia spp. among wild animals has mostly been studied in wild boar, but it has seldom been in other species. A total of 1,868 faecal samples from animals found dead or hunted were collected between 2015 and 2018 in the Valle d’Aosta region of the northwestern Italian Alps. Alpine ibex faecal samples were collected during a health monitoring program in 2018. Bacteria were isolated via PCR and confirmed as Y. enterocolitica biochemically. Strain antimicrobial susceptibility was tested by Kirby–Bauer disc diffusion, and the presence of virulence factors and antimicrobial resistance genes was investigated using whole-genome sequencing. Yersinia enterocolitica strains of biotype 1A were detected in six faecal samples from red deer (0.93%), roe deer (0.49%) and red foxes (0.7%). Strains found in beech martens (3.57%) and Alpine ibex (2.77%) belonged to biotypes 1B and 5, respectively and harboured the pYPTS01 plasmid that had only been detected in Y. pseudotuberculosis PB1/+. All the isolates were resistant to ampicillin and erythromycin. The biovar 1A strains exhibited different virulence factors and behaved like non-pathogenic commensals. The strain from an Alpine ibex also harboured the self-transmissible pYE854 plasmid that can mobilise itself and the pYPTS01 plasmid to other strains. The beech marten could be considered a sentinel animal for Y. enterocolitica. Phenotypic resistance may account for the ability of all the strains to resist β-lactams.
Mostrar más [+] Menos [-]Effects of bisphenol A and bisphenol F on porcine uterus contractility
2022
Zygmuntowicz, Aleksandra | Markiewicz, Włodzimierz | Grabowski, Tomasz | Jaroszewski, Jerzy
Bisphenols, as endocrine disruptors, may cause a wide range of health problems in humans, but so far, not all of them have been confirmed in animals, including pigs. Since animals are also exposed to bisphenols, we hypothesised that these substances may have an effect on uterine contractility in pigs. Therefore, the aim of the study was to investigate the effect of the most-used bisphenol, bisphenol A (BPA), and a selected analogue, bisphenol F (BPF), on the contractile activity of the pig uterus. The investigation utilised smooth muscles from immature pigs (n = 6), cyclic pigs on days 12–14 of the oestrous cycle (n = 6) or early pregnant pigs on days 12–16 of pregnancy (n = 6). Strips of the myometrium were exposed to BPA and BPF at concentrations of 10⁻¹³–10⁻¹ M. Smooth muscle contractility was determined with equipment for measuring isometric contractions. BPA caused a significant decrease in contraction amplitude, and frequency and in myometrial tension in all groups examined. BPF caused a decrease in the amplitude and frequency of contractions in all groups and in myometrial tension in the early pregnant group. The obtained results indicate that both BPA and BPF relaxed the porcine myometrium, but these changes, especially in the amplitude and frequency of contractions, were more evident after BPF treatment. The extent of relaxation is dependent on the physiological status of the animals.
Mostrar más [+] Menos [-]Genetic and pathogenic characterisation of a virulent Akabane virus isolated from goats in Yunnan, China
2022
Gao, Hua-Feng | Wang, Jin-Ping | Yang, Zhen-Xing | Xie, Jia-Rui | He, Yu-Wen | Hong, Qiong-Hua | Xin, Ai-Guo
Akabane virus (AKAV) has been detected in a variety of host species in China, but there are only limited records of its occurrence in goats. However, more attention needs to be paid to understanding the diversity of viruses in this species. The aim of the study was to explore the genotype characteristics and variation trend of AKAV and their relationship with virulence in Yunnan, China. Blood samples were collected from goats during routine surveillance of goat diseases in Yunnan province in 2019. The AKAV CX-01 strain was isolated using BHK-21 cells. To understand pathogenicity, the virus was intraperitoneally (IP) and intracerebrally (IC) inoculated into suckling mice and tissue samples were subsequently analysed histopathologically and immunohistochemically. Akabane virus CX-01 strain induced encephalitis and impairment of the central nervous system with fatal consequences. Phylogenetic analysis based on the ORF sequences of the small segments indicated that the AKAV isolate used was most closely related to the GD18134/2018 Chinese midge and bovine NM BS/1strains, while phylogenetic analysis based on the medium segments showed a close relationship between CX-01 and the Chinese GLXCH01 strain. The CX-01 isolate was related to AKAV genogroup Ia and probably originated from a recombination of different strains.
Mostrar más [+] Menos [-]Development of a real-time TaqMan PCR assay for the detection of porcine circovirus 4
2022
Chen Wanting | Jiang Dike | Xiao Lu | Zhang Pengfei | Luo Yan | Yang Zexiao | Yao Xueping | Wang Yin | Wu Xulong
Porcine circovirus 4 (PCV4) was first discovered in 2019 in a herd of pigs with porcine respiratory disease, dermatitis and nephropathy syndrome in Hunan Province, China. It has subsequently been detected in other provinces and in South Korea. In consideration of the potential of the virus to cause an epidemic, rapid, sensitive, and specific detection of PCV4 is needed, as is the facilitation of further epidemiological research through elucidation of the whole genome of PCV4. This study had those two aims.
Mostrar más [+] Menos [-]A new enzyme-linked immunosorbent assay for serological diagnosis of seal parapoxvirus infection in marine mammals
2022
Badr Yassien | Rahman Md. Matiur | Ohno Yoshito | Ishijima Keita | Maeda Ken | Kohyama Kaoru | Kamatari Yuji O. | Shimizu Kaori | Okada Ayaka | Inoshima Yasuo
Seal parapoxvirus (SPPV) infection has been reported among pinnipeds in aquaria in Japan; however, its seroprevalence is unknown. Therefore, an enzyme-linked immunosorbent assay (ELISA) was developed for serological diagnosis of SPPV infection.
Mostrar más [+] Menos [-]ASF -survivors’ sera do not inhibit African swine fever virus replication in vitro
2022
Walczak Marek | Juszkiewicz Małgorzata | Szymankiewicz Krzesimir | Szczotka-Bochniarz Anna | Woźniakowski Grzegorz
African swine fever virus (ASFV) causes one of the most dangerous diseases of pigs and wild boar – African swine fever (ASF). Since its second introduction into Europe (in 2007), the disease has been spreading consistently, and now ASF-free European countries are at risk. Complex interactions between the host’s immune system and the virus have long prevented the development of a safe vaccine against ASF. This study analysed the possibility of neutralisation of the ASFV in vitro by sera collected from ASF-survivor animals.
Mostrar más [+] Menos [-]Effect of oxidative status on the occurrence of haemolactia in dairy cows after calving
2022
Kuroiwa Tomoko | Matsuda Keiichi | Kanazawa Tomomi | Chee Hueyshy | Kimura Atsushi | Satoh Hiroshi | Sato Shigeru | Ichijo Toshihiro
Dairy cows may infrequently give milk tinged with blood after calving, which is a condition termed haemolactia. Economic losses for dairy farmers are caused by cases of haemolactia because of the condemnation of such milk, potential contamination of good bulk tank milk with haemolactic milk, and need for veterinarian intervention. This study was performed to elucidate the oxidative status of dairy cows with haemolactia during the peripartum period.
Mostrar más [+] Menos [-]Estrogen-related receptor α (ERRα) functions in the hypoxic injury of microglial cells
2022
Deng Chao-Yang | Zhu Ting-Ting | Lian Shuai | Wang Jian-Fa | Wu Rui | Zheng Jia-San
Hypoxia is a common pathological condition after spinal cord injury. Oestrogen-related receptor alpha (ERRα), as a key regulator of energy metabolism and mitochondrial functions, plays an important role in maintaining cell homeostasis. However, its role in hypoxic spinal microglia has not been fully elaborated. This study investigated the receptor’s activity when these cells are hypoxic and used as an in vitro model.
Mostrar más [+] Menos [-]Preliminary study on gene regulation and its pathways in Chinese Holstein cows with clinical mastitis caused by Staphylococcus aureus
2022
Wang Wenjia | Li Rongling | Ye Tingzhu | Zhang Xinxin | Chen Chao | Liang Ai-xin | Yang Li-guo
Clinical mastitis (CM) is one of the most common diseases of dairy cows globally, has a complex aetiology and recurs easily. Staphylococcus aureus is a frequently isolated pathogen responsible for bovine mastitis and remains difficult to eradicate.
Mostrar más [+] Menos [-]Protective effects of Bacillus subtilis fermentation extract against ochratoxin A-induced nephrotoxicity and immunotoxicity in broiler chickens
2022
Elhady Mohamed A. | Khalaf Abdel Azeim A. | Ibrahim Marwa A. | Hassanen Eman I. | Abdelrahman Rehab E. | Noshy Peter A.
Ochratoxin A (OTA) is a mycotoxin notably produced by Aspergillus and Penicillium spp. Bacillus subtilis fermentation extract (BSFE) contains specific enzymes which hydrolyse OTA. This study evaluated the efficiency of BSFE in ameliorating the immunotoxic and nephrotoxic effects of OTA in broiler chickens.
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