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Evaluation of Prevalence of the Most Important Bacterial and Protozoal Causes of Calf Diarrhea in Shahrekord Suburb Dairy Husbandries
2020
Moradi, Tohid | Azadbakht, Reza | Nejat Dehkordi, Shahin | Jafariyan Dehkordi, Mohsen | Momtaz, Hasan | Heidari Sureshjani, Masoomeh
BACKGROUND: Diarrhea syndrome is associated with irrecoverable damages in the husbandry industry worldwide due to losses resulted from fatality, weight loss, growing weak calves and treatment costs. Hence, investigation of diarrhea causes in different areas is important to attempt management strategies to prevent and control it. OBJECTIVES: Present study was carried to investigate prevalence of some important entropathogens in diarrheic calves until three months old, in Shahrekord suburb husbandries. METHODS: Fecal samples were taken from 82 female calves in first day of diarrhea and were examined for isolation of salmonella, Escherichia coli, clostridium, cryptosporidium, and coccidia through common microbiological and parasitological methods. RESULTS: In general, prevalence of isolated organisms were: salmonella 36.6%, Escherichia coli 24.4%, clostridium 9.8%, cryptosporidium 9.8%, and coccidian 7.31%, and Escherichia coli K99 were isolated from four calves. The most prevalent pathogens were Escherichia coli and Salmonella. CONCLUSIONS: The calves are unavoidably exposed to infectious causes of diarrhea during their whole lifespan, because they acquire organisms from environment immediately after birth. Therefore, attempts at efficient management methods, hygienic principles and receiving enough colostrum, particularly in cold seasons, may be efficient in the control, prevention and decrease of diarrhea and its subsequent losses.
显示更多 [+] 显示较少 [-]A study of oocyst shedding pattern and weight changes in neonatal calves experimentally infected with Cryptosporidium parvum
2015
Zarghami, Faisal | Mokhberdezfouli, Mohammadreza | Rahbari, Sadegh | Shayan, Parviz | Ebrahimzadeh, Elahe | Boloorchi, Mamood | Lotfolahzadeh, Samad
BACKGROUND: Cryptosporidium parvum is a protozoan parasite which belongs to apicomplexa phylum. The parasite infects both wild and domesticated animals and human beings as well. OBJECTIVES: The purpose of the present study was to detect oocyst shedding and diarrhea pattern in experimental cryptosporidiosis and their correlation with weight loss in neonatal calves. METHODS: Twelve Holstein calves of both sexes were obtained at birth from dairy farm and randomly divided into two groups of 6 calves. Six calves were orally infected with 107 C.Parvum oocysts at the 12h post parturition. The control group was not infected. Clinical signs were examined and fecal samples were collected by the rectal examination twice a day. All calves were weighed from day 0 to day 30 with 3 days intervals to determine effects of cryptosporidiosis on weight gain. RESULTS: All infected calves were noticeably depressed and had a decreased appetite from 3 days post inoculation (DPI) while they received colostrum. Subsequently, watery diarrhea with clumps of mucus and yellow or pale changes of feces color were observed. The infected calves have had diarrhea for 5-8 days that remarkably had got dehydrated. The most severity of diarrhea was 4-6 DPI. Oocyst excretion started 4 DPI, peaked at 6 DPI (60.48×106±9.03oocysts/g feces) and continued until 11 DPI. Control calves had no diarrhea and other clinical signs during the whole period of the trial. The mean weight gain of control group was significantly higher than inoculated group during experiment (p<0.001). The Weight of the infected calves was retarded until 9 days old and then risen subsequently. CONCLUSIONS: Present study showed the role of C.Parvum as the primary cause of diarrhea and weight loss among neonatal calves.
显示更多 [+] 显示较少 [-]Isolation, Characterization and Molecular Identification of Cryptosporidium spp. Causing Diarrhea in Young Calves by Multiplex Nested-PCR
2020
Nasiri, Vahid | Jameie, Farnoosh | Paykari, Habibollah
BACKGROUND: Diagnosis of Cryptosporidium species based on morphological characteristics is very limited and has no taxonomic value alone, and therefore the use of molecular methods removes these limitations to some extent. OBJECTIVES: The aim of this study was to determine the predominant Cryptosporidium genotypes in calves with diarrhea. METHODS: Study were conducted in calves aged less than 3 months for a period of 2 years. During the study period, 160 dung samples were collected from neonatal calves and examined first microscopically and then by molecular techniques. Stools were analyzed for the presence of Cryptosporidium oocysts by Sheather's Sugar Flotation Solution followed by Ziel-Neelsen staining method. DNA of parasite was extracted and multiplex nested-PCR protocol basis on the 18srRNA were done to identify three cattle-adapted species (C. andersoni, C. bovis and C. ryanae) plus the zoonotic species C. parvum. RESULTS: 110 fecal samples were collected from livestock in Alborz province and 50 fecal samples were collected from livestock in Shahroud city. Of the 160 animals examined, 90 were female and 70 were male. In total, out of 160 animals examined, 85 cases (53.12%) had diarrhea, of which 55 cases (34.37%) were positive using Ziel-Neelsen staining. Since all positive cases were related to diarrhea samples and related to calves under one month old, a significant relationship was observed between diarrhea status and the presence of this parasite (p < /em><0.05). In terms of seasonal distribution, no difference was observed in the rate of diarrhea and positive parasitic cases. The presence of 305 bp band in all Ziel-Neelsen positive samples confirmed the presence of C. parvum in all samples. CONCLUSIONS: Neonatal calves are more likely to be infected with Cryptosporidium parvum, as confirmed by the present study.
显示更多 [+] 显示较少 [-]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.
显示更多 [+] 显示较少 [-]Current status of porcine epidemic diarrhoea (PED) in European pigs
2019
Porcine epidemic diarrhoea (PED) is a highly contagious and devastating enteric disease of pigs caused by porcine epidemic diarrhoea virus (PEDV), an enveloped, single-stranded RNA virus belonging to the Alphacoronavirus genus of the Coronaviridae family. The disease is clinically similar to other forms of porcine gastroenteritis. Pigs are the only known host of the disease, and the occurrence of PED in wild boars is unknown. The virus causes acute diarrhoea, vomiting, dehydration, and high mortality in suckling piglets reaching 100%. Heavy economic losses in the pig-farming industry were sustained in the USA between 2013 and 2015 when PEDV spread very quickly and resulted in epidemics. The loss in the US pig industry has been estimated at almost seven million pigs. The purpose of this review is a description of the current status of porcine epidemic diarrhoea in European pigs and the risk presented by the introduction of PEDV to Poland in comparison to the epidemics in the USA.
显示更多 [+] 显示较少 [-]Porcine epidemic diarrhoea virus induces cell-cycle arrest through the DNA damage-signalling pathway
2020
Luo, Yi-Ran | Zhou, Shu-Ting | Yang, Liang | Liu, Yuan-Ping | Jiang, Sheng-Yao | Dawuli, Yeliboli | Hou, Yi-Xuan | Zhou, Tian-Xing | Yang, Zhi-Biao
Porcine epidemic diarrhoea virus (PEDV) infection causes watery diarrhoea, vomiting, anorexia, and weight loss, especially among neonatal piglets, inflicting on them morbidity and mortality potentially reaching 90%–100%. Despite it being known that certain mammalian cell phases are arrested by PEDV, the mechanisms have not been elucidated, and PEDV pathogenesis is poorly understood. This study determined the effect of an epidemic PEDV strain on cell cycle progression. We observed the effect of the PEDV SHpd/2012 strain on an infected Vero cell cycle through flow cytometry and Western blot, investigating the interrelationships of cell-cycle arrest, the DNA damage–signalling pathway caused by PEDV and the phosphorylation levels of the key molecules Chk.2 and H2A.X involved upstream and downstream in this pathway. PEDV induced Vero cell-cycle arrest at the G1/G0 phase. The phosphorylation levels of Chk.2 and H2A.X increased with the prolongation of PEDV infection, and no significant cell-cycle arrest was observed after treatment with ATM or Chk.2 inhibitors. The proliferation of PEDV was also inhibited by treatment with ATM or Chk.2 inhibitors. PEDV-induced cell-cycle arrest is associated with activation of DNA damage–signalling pathways. Our findings elucidate the molecular basis of PEDV replication and provide evidence to support further evaluation of PEDV pathogenesis.
显示更多 [+] 显示较少 [-]Characterisation of fowl adenovirus (FAdV-8b) strain concerning the geographic analysis and pathological lesions associated with inclusion body hepatitis in broiler flocks in Turkey
2020
Cizmecigil, Utku Yusuf | Umar, Sajid | Yilmaz, Aysun | Bayraktar, Erhan | Turan, Nuri | Tali, Besim | Aydin, Ozge | Tali, Hasan Emre | Yaramanoglu, Mehmetcan | Yilmaz, Semaha Gul | Kolukisa, Ahmet | Sadeyen, Jean-Remy | Munir, Iqbal | Yılmaz, Hüseyin
Fowl adenovirus can cause important diseases in chickens such as inclusion body hepatitis, hepatitis hydropericardium syndrome, and gizzard erosion and ulceration. Inclusion body hepatitis has been regularly reported from many countries. This is the first case report from Turkey, describing an outbreak of inclusion body hepatitis in broiler farms due to fowl adenovirus-8b (FAdV-8b). Broiler flocks with mortality about 10% were visited in Turkey, and necropsy was performed on dead birds. Samples were subjected to PCR assay to detect FAdV and other viral pathogens. After sequencing, phylogenetic analysis was performed and the nucleotide sequences of hexon genes were compared with the FAdV sequences data available in GenBank. Clinical signs such as anorexia, depression, ruffled feathers, huddling, and greenish diarrhoea were observed. Mortality started at the 8ᵗʰ day of age and ranged from 10% to 14%. Necropsy showed severe hepatitis, jaundice, and pancreatitis. The main necropsy findings included a pale, enlarged, haemorrhagic, and friable liver along with swollen and haemorrhagic kidneys and spleen. PCR and sequence analysis revealed the presence of fowl adenovirus serotype 8b (FAdV-E). This is the first report on characterisation and the pathological lesions associated with FAdV in broilers in Turkey. Our findings suggest that FAdV strains could be an emerging pathogen in Turkish broilers and could actively contribute to hepatitis and immunosuppression.
显示更多 [+] 显示较少 [-]Detection and molecular analysis of bovine enteric norovirus and nebovirus in Turkey
2018
Turan, Turhan | Işıdan, Hakan | Atasoy, Mustafa Ozan | Irehan, Bünyamin
Bovine Norovirus (BoNeV) which has been confirmed in Asia, America, and Europe, seems to be distributed worldwide, even though only reported from a number of countries. Bovine noroviruses are predominantly detected in diarrhoeic animals rather than neboviruses. The study reveals the importance of noro- and neboviruses in early age diarrhoea of calves. A total of 127 stool samples were collected from three provinces located in the central region of Turkey. Samples were subjected to nucleic acid isolation and reverse transcription and polymerase chain reaction (PCR). Positive samples were sequenced and analysed. According to PCR, five samples (3.93%) were found to be positive for bovine norovirus while 32 (25.19%) samples were found to be positive for bovine nebovirus. Phylogenetic analysis indicated that the novel Turkish norovirus strains were found to be of genotype III.2 and all novel neboviruses were substituted under Nebraska-like strains. Although predominantly bovine noroviruses are detected worldwide, the study indicated that bovine neboviruses were more prevalent in the studied area. We suggest that bovine neboviruses are more frequently responsible for calf diarrhoea than supposed by virologists. This is also the first report of neboviruses other than Kirklareli virus which is distantly related to neboviruses detected in Turkey.
显示更多 [+] 显示较少 [-]Characterisation of porcine enteropathogenic Escherichia coli isolated in northeastern India
2020
Kylla, Hosterson | Dutta, Tapan Kumar | Roychoudhury, Parimal | Subudhi, Prasant Kumar | Lalhruaipuii, | Lalsiamthara, Jonathan | Mandakini, Rajkumari
Enteropathogenic Escherichia coli (EPEC) is one of the main pathotypes causing gastroenteritis, particularly in young immunocompromised hosts. The study reports the prevalence, characterisation, and molecular epidemiology of EPEC from piglets in northeastern India. A total of 457 faecal samples were collected, from which 1,286 E. coli strains were isolated and screened by PCR. The resultant EPEC strains were serotyped and phenotypically characterised for resistance against 15 antimicrobials. Also, the phylogenetic sequence was analysed for 11 selected strains. A total of 42 strains (3.26%) belonged to atypical EPEC, of which, 15 (35.71%, and 2.29% of the 654 strains from this farm type) were isolated from organised and 27 (64.29%, and 4.27% of the 632 strains from this farm type) from unorganised farms; further, 5 (11.90% of the EPEC strains and 1.51% of the 330 strains from this breed) were isolated from the indigenous breeds and 37 (88.10%, and 3.87% of the 956 strains from this breed) from crossbred piglets. Serogroups O111 (11.9%) and O118 (7.14%) were the most prevalent of the 10 present. Sequence analysis of a length of the eaeA gene of 11 isolates of the region showed them to have 100% homology with each other and their identity ranged from 99.4% to 99.7% with GenBank reference sequences. All the EPEC isolates were multi-drug resistant, showing the highest resistance to amoxicillin (80.9%) and cephalexin (76.19%). The study highlighted the association of EPEC with piglet’s diarrhoea in northeastern India. EPEC isolates belonged to many serotypes and phenotypically all were multi-drug resistant with close genetic homology.
显示更多 [+] 显示较少 [-]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.
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