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Delayed seroconversion following naturally acquired caprine arthritis-encephalitis virus infection in goats.
1993
Rimstad E. | East N.E. | Torten M. | Higgins J. | DeRock E. | Pedersen N.C.
One hundred eight milking goats from a dairy that had been using a modified caprine arthritis-encephalitis virus (CAEV) eradication program were tested for CAEV antibodies by serologic methods and for proviral CAEV DNA by use of polymerase chain reaction (PCR) technology. All goats were free of clinical symptoms of CAEV infection. Twenty-seven of the 108 goats were considered seropositive, on the basis of ELISA results. Proviral CAEV DNA was detected, using PCR techniques, in mononuclear leukocytes in blood samples obtained from 25 of the these 27 seropositive goats. Twenty of the 81 seronegative goats also had positive PCR test results. Ten of these goats seroconverted by 8 months later, and virus was readily isolated from mononuclear leukocytes in venous blood samples after the goats had seroconverted. Virus was also isolated from mononuclear leukocytes in blood samples collected from 4 of 11 goats that were seronegative, but had positive PCR test results. These results indicated that seroconversion can be delayed for many months following natural infection with CAEV. Delayed seroconversion appears to be a feature of CAEV infection, which may have direct implications for CAEV eradication programs and epidemiologic studies that rely on serologic methods to detect infected goats.
Afficher plus [+] Moins [-]A cross-sectional study of bovine tuberculosis in selected dairy farms in Ethiopia
2003
Ameni, G. | Bonnet, P. | Tibbo, Markos
A cross-sectional study to determine individual animal prevalence of bovine tuberculosis (BTB) was conducted on 1171 dairy cattle in 12 randomly selected dairy farms in Ethiopia between January 1999 and May 2001 using comparative intradermal tuberculin (CIT) test and bacteriologic study through milk culturing. An overall individual animal prevalence of 46.8% (548 of 1171 animals) and a herd prevalence of 91.7% (11 of 12 farms) were recorded in 12 dairy farms by the CIT test. There were significant (P <0.0001) differences in individual prevalence between farms and breeds (pure Holstein and their crosses with Zebu). There was positive correlation (r = 0.41) between herd size and prevalence of bovine tuberculosis. Furthermore, a negative linear association (R2 = 0.24) was found between mean score of management of the farm and prevalence, indicating that the prevalence of bovine tuberculosis could be improved by sanitary measures. Breed and management affected the prevalence of BTB (R2 = 0.30) as confounding variables. Mycobacterium bovis was isolated from the milk of 13.3% (4 of 30) reactor cows. The widespread occurrence of BTB in the study farms and isolation of M. bovis from the milk of reactor cows signify its economic importance and potential risk to public health. Generalization and improved use of milk pasteurization within all dairy subsectors is recommended, and this would affect the competitiveness of the dairy sector in Ethiopia.
Afficher plus [+] Moins [-]Whole genome sequence of Brucella melitensisl local isolate from an infected goat in Malaysia
2016
Mohd Mokhtar Arshad | Ramlan Mohamed | Shuhaila Mat Sharani | Hardy Abu Daud | Omer Khazaal Sallou | Mohd Azam Khan Goriman Khan | Hirzahida Mohd. Padil
Brucellosis in goats is mainly caused by the bacterium Brucellamelitensis, which is one of the most important pathogenic species in the world. In Malaysia, the annual prevalence data of brucellosis was recorded in goats and the control strategy of the disease basedon test and cull of infected animals. This strategy has caused huge economic losses to farmers and government alike. Therefore, whole genome sequencing of B. melitensis local strain is essential forimproving the current vaccine. B. melitensis strain VRI 6530/11 wasobtained from veterinary research institute biobank, Ipoh. The strain was submitted for classical identification procedures and the total genomic DNA was extracted by using DNeasy blood and tissue kit(QIAGEN). The concentration and purity of DNA were determined by using agarose gel electrophoresis and spectrophotometer (DNA/RNA) assay respectively. The genome was sequenced by using IlluminaHiSeq platform with insert size ~200 bp. A total of 1.0 Gb data was generated from the sample. More than 95% of sequencing data was retained in the sample after quality filtering, this indicatethe sequencing reads are of high quality. Final assembly had 33 scaffolds with total size ~3.28 Mb, 44 contigs, GC content is 57.25%, N50 is 293,291. A total of 3,238 protein coding genes, 48 tRNAs and 3rRNAs were predicted and over 87% of the genes were functionally annotated. Genome sequencing of a local B. melitensis strain is the first of its kind in Malaysia and work from this study can contribute towards the development of a new effective vaccine for the control ofthe disease in the country.
Afficher plus [+] Moins [-]Investigation of high fatality among lambs in sheep farms in Pekan, Pahang, Malaysia
2016
Rosilawati K. | Nurul Faizah Z. | Saipul Bahari A. R.
This study was conducted to investigate the high mortality of young lambs in two sheep farms in Pekan, Pahang over a period of 3 years. Samples from postmortem of 1,451 lambs below one year of age by a farm veterinarian were submitted for laboratory diagnosis at the Bacteriology Section of the Regional Veterinary Diagnostic Laboratory in Kuantan. Escherichia coli is the most commonly recorded bacteria with 161 lambs diagnosed in 2013. In 2014 and 2015, there was a decrease in occurrence of E. coli related deaths, with 120 and 75lambs respectively. A total of 25% of the cases showed Escherichia coli positive by culture on blood agar and MacConkey agar, and confirmed by biochemical tests. A total of 21% of the cases were positive for staphylococcus sp, 3% and 6% for Streptococcus sp and Klebsiella pneumonia, respectively. Other bacteria were isolated in 45% of the cases. It was further noted that a total of 285 lambs between the ages of one to four months of age followed by 58 lambs (20%) less than one month old had E.coli isolation. It is also noteworthy that there were 10 lambs with E.coli infection in one to fourteen day-old lambs during the 3-year period from January 2013 to December 2015. This information was collated as a result of routine diagnosis of field cases submitted and with the intention of highlighting the common pathogens causing high mortality in local small ruminant farms so that preventive action may be taken for future farming ventures. E. coli infections or Colibacillosis is an important finding and indicator of poor management including poor nutrition, hygiene and environmental contamination which can reduce animal immunity and render it susceptible to other infections.
Afficher plus [+] Moins [-]Isolation and molecular characterization of Brucella abortus and Brucella melitensis from samples received by the Regional Veterinary Laboratory, Bukit Tengah, Malaysia
2017
Thenamutha M. | Zakiah M. D. | Azizul O. | Maswati M. A.
A study was carried out to report the phylogenetic analysis of Brucella abortus and Brucella melitensisby using molecular techniques from samples submitted to the Regional Veterinary Laboratory, Bukit Tengah.In this study, identification and genetic characterization of Brucella isolated samples using molecular analysis based on IS711 sequence between localisolates and foreign countries accesses in GenBank was done successfully. A total of 31 samples were isolated for Brucella species and then were amplified byPCR, directly sequenced and compared genetically to published sequences which were obtained from GenBank. The most common Brucella species that was found in both bovine (76.5%) and caprine (85.7%) through diagnostic samples in Regional Veterinary Laboratory, Bukit Tengah, was Brucella melitensis. PCR and sequencing were confirmed positive with 76.5% for Brucella melitensis, 23.5% for Brucella abortus and 23.5% for mixed infectionfrom the total of 17 bovine samples. In caprine, the detection of Brucella melintesis and Brucella abortus showed 85.7% and 21.4% respectively meanwhile total mixedinfection showed 21.4%. These clustering between local isolates of Brucella melitensis were phylogenetically related to other Asian countries such as Singapore,Yemen and Saudi Arabia. The Neighbour Joining Analysis clustered the Brucella abortus local isolates for both bovine and caprine were most closely related to India,Iran, Italy and USA. Interestingly, all the isolates within Malaysia have a close relationship (>95%) with the low level of genetic diversity. When local isolates arecompared to GenBank data, it gives an indication on the possible sources of these infections. Eventually, it will improve the import and export policies to controlbrucellosis in Malaysia.
Afficher plus [+] Moins [-]Avian adenovirus isolated from broiler affected with inclusion body hepatitis
2016
Redzuan I. | Norsharina A. | Ardy A. | Norina L. | Nurnadiah A. H. | Nor-Ismaliza I.
Inclusion body hepatitis (IBH) has been reported in many countriesin the world. The IBH characterized presence of intra-nuclear inclusion bodies in hepatocytes in chickens. On December 2015, an onset of high acute mortality in a flock of 12, 18 and 23- day-old broiler chickens in Malacca and Johore was reported to the RegionalVeterinary Laboratory, Johor Bahru, Peninsular Malaysia. The birds showed lethargy, huddling, ruffled feathers, and inappetence. At necropsy, the livers were enlarged, pale yellow, friable andwith multiple petechial hemorrhages, the kidney were congested and enlarged, with hydropericardium and gizzard erosion. Large eosinophilic intranuclear inclusion bodies were seen in hepatocytes. PCR revealed liver were positive of FAdV at expected band of 1219 bp and the nucleotide sequence share 95-99% identity with the fowl adenovirus species E, serotype 8b. Based on the acute high mortality, age of the broilers, gross and microscopic lesions (especially intranuclear inclusion bodies) and molecular finding, the condition was diagnosed as adenovirus inclusion body hepatitis.
Afficher plus [+] Moins [-]Optimized protocol for multiplex nested polymerase chain reaction to detect and differentiate Haemophilus parasuis, Streptococcus suis, and Mycoplasma hyorhinis in formalin-fixed, paraffin-embedded tissues from pigs with polyserositis
2012
Kang, Ikjae | Kim, Duyeol | Han, Kiwon | Seo, Hwi Won | Oh, Yeonsu | Park, Changhoon | Lee, Jeehoon | Gottschalk, Marcelo | Chae, Chanhee
An optimized protocol was developed for the simultaneous detection and differentiation of Haemophilus parasuis, Streptococcus suis, and Mycoplasma hyorhinis in formalin-fixed, paraffin-embedded (FFPE) tissues with multiplex nested polymerase chain reaction (PCR). This method also determines the prevalence of these bacteria in pigs with polyserositis. DNA extraction with a combination of a commercial reagent and proteinase K resulted in more frequent detection of the pathogens than DNA extraction with proteinase K alone. Among FFPE tissue samples from 312 cases of polyserositis in which at least 1 bacterial species was detected, multiplex nested PCR detected H. parasuis in 239 (77%), S. suis in 124 (40%), and M. hyorhinis in 40 (13%). The disease was caused by a single pathogen in 224 (72%) of the cases and multiple pathogens in 88 (28%). Among the pigs positive for H. parasuis, S. suis, and M. hyorhinis by multiplex nested PCR, the pathogen was isolated from only 11%, 35%, and 28%, respectively. Therefore, the PCR protocol developed in this study is a useful diagnostic method when samples are negative after isolation methods and even for samples in which only 1 pathogen was isolated.
Afficher plus [+] Moins [-]Isolation of Mycoplasma gateae from a cat suspected with feline parvovirus infection
2021
Harnita E. | Dahlia H. | Nor Liyana M. R. | Muhammad Marwan I. | Zarrahimah Z.
Recently, diagnostic cases of Mycoplasma screening from feline kept rising. In 2018, there were two cases in felines that were positively diagnosed as Mycoplasma co-infection in which one of the two cases was due to mycoplasmosis. Diagnosis of mycoplasmosis was based on isolation and identification using biochemical testing. Mycoplasma was successfully isolated from both cases. Based on the feline death case, the result indicated that Mycoplasma gateae was isolated from the blood-stained trachea sample. In contrast, none was isolated from the lung. As the infection was associated with other microorganisms, this case concluded that the cause of death of the cat was due to Parvovirus with secondary infection of Mycoplasma gateae.
Afficher plus [+] Moins [-]Molecular characterization of fowl adenoviruses isolated from chickens in Malaysia
2021
Faizul Fikri M. Y. | Syamsiah Aini S. | Ong, G. H. | Maizatul Z. | Muhammad Redzuan S. | Mohammad Jiha R. | Leow, B. L.
Recently, Fowl Adenovirus (FAdV) cases have been reported in many countries worldwide. FAdV is a contagious agent associated with inclusion body hepatitis (IBH) and hydropericardium syndrome (HPS) in chickens. It belongs to the Aviadenovirus genus of the family Adenoviridae. The virus is classified into five species (A to E) and further divided into 12 serotypes. Depending on the serotypes, they have diverse characteristics of virus that can either be pathogenic or nonpathogenic strain. From the viewpoint of epidemiological as well as vaccine development, it is very important to detect FAdV strains. Previous studies have been conducted on molecular research, but the continuity of this study in Malaysia has been limited. This study aims to identify the serotype classification of five Malaysian FAdV isolates obtained from field outbreaks during 2017-2019. In this study, polymerase chain reactions (PCR) were conducted based on Hexon gene. Results from the nucleotide sequence analysis discovered that the five isolates showed high similarity with FAdV-8b strains. High bootstrap values in phylogenetic analysis supported the clustering of the Malaysian FAdVs isolates into FAdVs species E. Consequently, the result of this study contributed important information on the epidemiology and culminated in the importance of control strategies against FAdV infection in Malaysia.
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