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Cytologic and bacteriologic evaluation of tracheobronchial aspirates from clinically normal foals.
1989
Crane S.A. | Ziemer E.L. | Sweeney C.R.
Thirty-eight tracheobronchial aspirates (TBA) were collected from twenty 1 to 6-month-old foals, which were free of clinical signs of respiratory tract or other infectious disease. We collected TBA from 9 of the foals 3 times when they were approximately 8, 16, and 24 weeks old. Aspirates were examined cytologically after staining with modified Wright-Giemsa, Gram, toluidine blue, and prussian blue stains. Aerobic bacterial culturing was performed on all aspirates. Of the 20 initial TBA, 4 (20%) were normal cytologically on the basis of previously defined criteria for TBA from clinically normal horses, 6 (30%) had a high percentage of eosinophils (> 5%), 8 (40%) were classified as indicative of subacute inflammation, and 2 (10%) were classified as indicative of acute inflammation. Nine (45%) were positive for mast cells and none were positive for hemosiderin-laden macrophages (hemosiderophages). Of the 9 foals from which samples were collected at 16 and 24 weeks of age, results were similar, except for an increase in the number of TBA classified as indicative of chronic inflammation (33% and 22% respectively) and the number positive for hemosiderophages (33% and 88%, respectively). One TBA was considered nondiagnostic because of pharyngeal contamination. Culturing of 12 of the 37 aspirates (32%) yielded a potential microbial pathogen. Only 2 were positive cultures from the same foal. The following organisms were isolated: beta-hemolytic Streptococci spp (4), Actinobacillus/Pasteurella spp (4), Rhodococcus equi (2), unidentified nonenteric Gram-negative rod (1), and Escherichia coli (1). Thirty-four of the 37 aspirates (92%) yielded light growth of various organisms considered to be nonpathogenic and normal inhabitants of the upper respiratory tract. It was concluded that the presence of inflammatory cells, eosinophils, and mast cells in the tracheobronchial aspirates from clinically normal foals is a common finding. These cytologic findings were consistent in the samples collected from foals at 8, 16, and 24 weeks of age. It was also concluded that bacteria with recognized pathogenicity can be isolated from TBA from clinically normal foals and were most frequently isolated from 1- to 2-month-old foals or those with cytologic evidence of inflammation, even in the absence of clinical signs of respiratory tract disease.
显示更多 [+] 显示较少 [-]Pharmacokinetics, bioavailability, and in vitro antibacterial activity of rifampin in the horse.
1988
Wilson W.D. | Spensley M.S. | Baggot J.D. | Hietala S.K.
The pharmacokinetics and bioavailability of rifampin were determined after IV (10 mg/kg of body weight) and intragastric (20 mg/kg of body weight) administration to 6 healthy, adult horses. After IV administration, the disposition kinetics of rifampin were best described by a 2-compartment open model. A rapid distribution phase was followed by a slower elimination phase, with a half-life (t1/2[beta]) of 7.27 +/- 1.1 hours. The mean body clearance was 1.49 +/- 0.41 ml/min.kg, and the mean volume of distribution was 932 +/- 292 ml/kg indicating that rifampin was widely distributed in the body. After intragastric administration of rifampin in aqueous suspension, a brief lag period (0.31 +/- 0.09 hour) was followed by rapid, but incomplete, absorption (t1/2[a] = 0.51 +/- 0.32 hour) and slow elimination (t1/2[d] = 11.50 +/- 1.55 hours). The mean bioavailability (fractional absorption) of the administered dose during the first 24 hours was 53.94 +/- 18.90%, and we estimated that 70.0 +/- 23.6% of the drug would eventually be absorbed. The mean peak plasma rifampin concentration was 13.25 +/- 2.70 microgram/ml at 2.5 +/- 1.6 hours after dosing. All 6 horses had plasma rifampin concentrations > 2 microgram/ml by 45 minutes after dosing; concentrations > 3 microgram/ml persisted for at least 24 hours. Mean plasma rifampin concentrations at 12 and 24 hours after dosing were 6.86 +/- 1.69 microgram/ml and 3.83 +/- 0.87 microgram/ml, respectively. We tested 162 isolates of 16 bacterial species cultured from clinically ill horses for susceptibility to rifampin. All strains of coagulase-positive staphylococci, Streptococcus zooepidemicus, Str equi, Str equisimilis, Rhodococcus equi and Corynebacterium pseudotuberculosis were highly susceptible to rifampin (minimal inhibitory concentration [MIC] less than or equal to 0.25 microgram/ml).
显示更多 [+] 显示较少 [-]Effects of weaning on diarrhea caused by enterotoxigenic Escherichia coli in three-week-old pigs.
1988
Sarmiento J.I. | Dean E.A. | Moon H.W.
We attempted to determine whether weaning is required for induction of diarrhea in pigs with postweaning enterotoxigenic Escherichia coli infection. Three-week-old newly weaned pigs and their suckling littermates were inoculated with the K88+ enterotoxigenic E coli strain M1823B. Fourteen of 21 weaned and 12 of 20 suckling pigs were genetically resistant to intestinal adhesion by the K88+ strain of E coli; they remained healthy, and gained weight at similar rates. Both groups of K88-resistant pigs gained weight faster, and shed fewer bacteria of strain M1823B in their feces, than did their K88-susceptible counterparts. Diarrhea developed in K88-susceptible pigs in the weaned (6 of 7 pigs) and suckling (4 of 8 pigs) groups, and 1 of the 4 affected suckling pigs died from complications resulting from diarrhea. The incidences of diarrhea, weight gain rates, and the numbers of strain M1823B shed in feces of susceptible weaned and suckling pigs were not significantly (P > 0.05) different. Diarrhea scores of susceptible weaned pigs were significantly (P < 0.02) higher than those of susceptible suckling pigs on the second day after inoculation. In this experimental model, it was concluded that weaning is not required for induction of diarrhea, but may modestly increase its severity.
显示更多 [+] 显示较少 [-]Balantidium coli in pig farms suspected of porcine circovirus type 2 (PCV2) associated enteritis
2021
Szczotka-Bochniarz, Anna | Karamon, Jacek | Nowak, Agnieszka | Porowski, Marian | Karbowiak, Paweł | Holeniewski, Andrzej | Pejsak, Zygmunt
Diarrhoea in growing-finishing pigs is a common problem of commercial pig farms. Among many causative factors, porcine circovirus type 2 (PCV2) is one considered an important pathogen in modern pig production. The aim of the study was to verify if PCV2 was responsible for antibiotic non-responsive diarrhoea and wasting in pigs. A total of 13 dead pigs aged between 12 and 15 weeks from three Polish farms with persistent herd symptoms suggestive of PCV2 infection were provided for evaluation. Sections of lymph nodes and intestines were analysed by in situ hybridization (ISH) for PCV2 and histopathological examination. Faeces and intestinal scrapings were tested for Lawsonia intracellularis and Brachyspira hyodysenteriae by real-time PCR and for parasitic infection by flotation and decantation. ISH and histopathological examination showed that all pigs were PCV2 systemic disease negative. Swine dysentery was confirmed by real-time PCR on two farms, and proliferative enteropathy on one farm. In histological examinations, erosions of the caecal and colonic mucosa were found, together with cysts and trophozoites of Balantidium coli. The protozoa were present in the intestinal lumen and mucosa. B. coli cysts were identified in faeces from all examined pigs. These results suggest that monitoring of B. coli infections should be an additional measure of control and prevention of gastrointestinal tract disorders in modern swine husbandry.
显示更多 [+] 显示较少 [-]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.
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 [-]Prevalence and phylogenetic analysis of Mycoplasma synoviae strains isolated from Polish chicken layer flocks
2019
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka, Anna
Introduction: Mycoplasma synoviae (MS) is a chicken pathogen of major economic importance. Material and Methods: Between 2010 and 2016, 906 commercial layer chicken flocks in Poland were examined for MS, and the phylogenetic relationship among the strains was established. Regionally dispersed samples were collected and tested with the use of real-time PCR to detect the 16S–23S intergenic spacer region. Positive samples were also tested with LAMP and conventional PCR to detect the vlhA gene. Results: MS genetic material was detected in 265 (29%) of the tested flocks by real-time PCR, in 227 by the LAMP method and in 202 (22%) by conventional PCR. The by-year percentage of positive samples began at 34% in 2010, rose to 44% in 2012, and declined to 29% in 2016. A phylogenetic analysis of Polish M. synoviae strains using a partial sequence of the vlhA gene showed nine genotypes (A–I), the most frequently occurring being F and C. Pathogenic Polish MS field isolates (n = 27) collected from chickens with clinical signs of infection were grouped for their characteristic symptoms: respiratory for genotypes C, E, F, and I (n = 13), EAA and a drop in laying for genotypes F, E, and C (n = 12), and synovitis for genotype A (n = 2). Conclusion: These data showed the country’s isolate diversity. The high prevalence suggests the need to introduce appropriate control programmes. This is the first report of molecular epidemiological data on M. synoviae infection in layer chickens in Poland.
显示更多 [+] 显示较少 [-]Evaluation of the possibility of C. burnetii transmission by the alimentary route in a guinea pig model
2019
Jodełko, Agnieszka | Szymańska-Czerwińska, Monika | Kycko, Anna | Niemczuk, Krzysztof
Q fever (coxiellosis) is an infectious disease of animals and humans, caused by.C. burnetii and widely distributed throughout the world. It is known that people and animals acquire the disease predominantly.via inhalation of infectious aerosols. The possibility of transmission of the pathogen by the alimentary route is still a matter of debate and remains controversial. Therefore the aim of this study was to fill the gaps in knowledge of oral transmission of.C. burnetii by conducting biological tests on the guinea pig model. Guinea pigs, divided into five groups comprising a negative control and four experimental groups, received specified concentrations of.C. burnetii per os. To determine the presence of specific antibodies, blood samples were tested using CFT. Also, internal organs collected during necropsy were screened by a real-time PCR targeting I.1111. Additionally, histopathological evaluation of the tissues was performed. The presence of antibodies and pathogen DNA in caecum was confirmed in one guinea pig from experimental group IV..C. burnetii was also detected in testicular tissue collected from one animal of experimental group II. The presence of pathogen DNA in the testicular tissue indicates that infection spreads haematogenously. In the majority of experimental animals specific antibodies and genetic material of.C. burnetii were not detected. This fact suggests that development of infection depends on many factors, such as animal immune status.
显示更多 [+] 显示较少 [-]Identification and molecular characterisation of bovine parainfluenza virus-3 and bovine respiratory syncytial virus - first report from Turkey
2019
Timurkan, Mehmet Ozkan | Aydın, Hakan | Ahmet Sait,
Introduction: Bovine parainfluenza virus-3 (BPIV3) and bovine respiratory syncytial virus (BRSV) are the cause of respiratory disease in cattle worldwide. With other pathogens, they cause bovine respiratory disease complex (BRDC) in ruminants. The aim of the study was the detection and molecular characterisation of BPIV3 and BRSV from nasal swabs and lung samples of cows in and around the Erzurum region of eastern Turkey. Material and Methods: In total, 155 samples were collected. Of animals used in the study 92 were males and 63 females. The age of the animals was between 9 months and 5 years, mean 1.4 years. Most males were in the fattening period and being raised in open sheds; females were in the lactating period and kept in free stall barns. All samples were tested for the presence of viral genes using RT-PCR. Gene-specific primers in a molecular method (RT-PCR) identified BRSV (fusion gene) and BPIV3 (matrix gene) strains at the genus level. Results: RNA from BRSV and BPIV3 was detected in two (1.29%) and three (1.93%) samples, respectively, one of each of which was sequenced and the sequences were aligned with reference virus strains. Phylogenetic analyses clustered the strains in genotype C/BPIV3 and subgroup III/BRSV. Conclusion: The results indicate that BRSV and BPIV3 contribute to bovine respiratory disease cases in Turkey. This is the first report on their detection and molecular characterisation in ruminants in Turkey.
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.
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