Timothy Woma - Academia.edu (original) (raw)

Papers by Timothy Woma

Archives of Veterinary Science, 2008

DogSLAM cells and its application to diagnosis

The aim of the study is to determine the epizootiology of Peste des petits ruminants (PPR) in Tur... more The aim of the study is to determine the epizootiology of Peste des petits ruminants (PPR) in Turkey during 2010-2012, using molecular genotyping. Samples of blood (n=193), swab (n=7) and tissue (n=374) were collected from sheep (n=473) and goats (n=101) suspected of having PPRV infection from an outbreak in 50 provinces of Turkey during 2010-2012. These samples (n=574) were tested using reverse transcription polymerase chain reaction (RT-PCR) and real-time reverse transcription polymerase chain reaction (RT-qPCR) targeting selected parts of the fusion (F) and the nucleocapsid (N) genes. Positivity ratios were 35.5%, 39.3%, and 44.4% with regards to RT-PCR targeting the F and the N genes, and RT-qPCR targeting the latter gene (N), respectively. The overall positivity rate was 45.8%. For sequence analyses, F-gene (n=53) and N-gene (n=60) positive samples representing different provinces were selected. After phylogenetic analysis, the circulating PPRV was located in lineage IV according to two gene regions. The F-gene partial sequence analysis at the nucleotide level showed 98.2-100% resemblence among 53 for F-gene, and 97.9-98.9% and 91.3-92.4% to Turkey2000 and Nigeria75/1 sequences, respectively. The N-gene partial sequence analysis at the nucleotide level showed 94.2-100% resemblence among 60 for N-gene, and 94.2-98.3% and 89.3-90.9% to Turkey2000 and Nigeria75/1 sequences, respectively. The result of this study indicates that PPRV infection is enzootic in Turkey, and belongs to the lineage IV, which is present in three haplogroup. The phylogenic analysis indicates the spread of the virus is associated with unauthorized movement of stock.

Veterinary Medicine and Science

Peste-des-petits-ruminants (PPR) and Goat pox (GTP) are two devastating and economically importan... more Peste-des-petits-ruminants (PPR) and Goat pox (GTP) are two devastating and economically important transboundary animal diseases of small ruminants in Africa and Asia that have been difficult to control. This study however, investigated an outbreak of PPR and GTP in a mixed flock of indigenous sheep and goats in Kanam, North Central Nigeria. A total of nine sera and seven tissues (lungs, spleen, scab and skin) samples were collected and analysed in the laboratory using competitive enzyme linked immunosorbent assay (cELISA) for PPR antibodies and polymerase chain reaction (PCR) for detection of PPR virus (PPRV) and GTP virus (GTPV). Gene fragments of the nucleoprotein of PPRV and the G-protein-coupled chemokine receptor (GPCR) of GTPV were amplified and sequenced to confirm the presence of the causative viruses. Serologically, antibodies to PPRV were detected in all (9/9) sera collected. GTPV and PPRV was detected in corresponding samples (42.8% n = 3/7) of the scab/skin samples collected by both PCR and RT-PCR technique. The phylogenetic analysis of PPRV revealed that the virus belongs to lineage IV and clustered with viruses from Gabon and Cameroon. Similarly, the GTPV also clustered with other sequences from Burkina Faso and Yemen. The positive cELISA, RT-PCR and PCR results from samples collected from the same animals confirmed co-infection of PPR and GTP in this mixed flock of sheep and goats. This is the first report of concurrent infection of PPR and GTP in mixed flock of sheep and goats in Nigeria. Our findings underscore the need for farmers to vaccinate their flock to control spread and economic losses as result of these diseases.

Open veterinary journal, 2018

Camel contagious ecthyma (CCE) is a viral disease of camelids that is caused by a Parapoxvirus (P... more Camel contagious ecthyma (CCE) is a viral disease of camelids that is caused by a Parapoxvirus (PPV) which is a DNA virus of the viral family: . Diseases affecting camels in Nigeria are scarcely reported. CCE or the laboratory detection of camel PPV (CPPV) has not been reported in Nigeria. This study investigated and described the clinical presentation of CCE and molecular detection of CPPV in Nigeria. Suspected cases of CCE were reported in a farm, live animal market and abattoir, in three different states (Bauchi, Plateau and Zamfara) in Northern Nigeria. Skin scabs, lungs, liver and intestine samples were collected. Polymerase chain reaction (PCR) was carried out using the primers which targets the RPO30 gene fragment of the genus PPV. The clinical signs observed from the suspected cases of CCE were proliferative skin lesions, papules, scabs on the lips and nares. CPPV was detected in 80.0% (4/5) of the samples collected by PCR. CCE was diagnosed based on clinical signs and PCR r...

Tropical Medicine and Infectious Disease

The aetiological agent of rabies is a member of the Lyssavirus genus (Rhabdoviridae family, order... more The aetiological agent of rabies is a member of the Lyssavirus genus (Rhabdoviridae family, order Mononegavirales). The disease (rabies) is endemic in many parts of Asia and Africa and still remains an important public and veterinary health threat. In Nigeria, there is a dearth of information on the natural infection and/or exposure of bat species to lyssaviruses. Therefore, this study was undertaken to assess the prevalence of rabies virus (RABV) neutralizing antibodies in sera obtained from bats from the central Plateau and North-East Bauchi States in Nigeria. Two hundred serum samples were collected from Nigerian fruit bats from six different locations and tested for anti-RABV antibodies using a commercial blocking ELISA. Of the 200 bat serum samples collected, one batch consisting of 111 samples did not meet the validation criteria and hence was not included in the final analysis. Of the remaining 89, only three (3.4%) contained anti-lyssavirus antibodies, demonstrating a low prevalence of lyssavirus antibodies in the study population. In order to further understand the exposure of bat species to phylogroup II lyssaviruses (Lagos bat virus and Mokola virus), the same panel of samples will be tested for neutralizing antibodies to phylogroup II members, viruses that do not cross-neutralize with members of phylogroup I.

African journal of infectious diseases, 2017

Sixty (60) male West African Dwarf goats were reported with clinical signs of enlarged lymph node... more Sixty (60) male West African Dwarf goats were reported with clinical signs of enlarged lymph nodes, scabs on the mouth, nose and ears. Two of the goats died and post mortem examination reveals enlarged submandibular lymph nodes and vesicular lesions on the tongue. Clinical diagnosis of Orf has been reported in Nigeria but this report is the confirmatory diagnosis of Orf in a suspected outbreak in an experimental farm in Uyo, Akwa Ibom State, Nigeria using molecular techniques. Scabs, spleen and lymph node samples from goats suspected to have died from Orf were collected, transported on ice to the laboratory and homogenized. The DNA was extracted using QIAmp DNA minikit (Qiagen) according to the manufacturer's instructions. Orf virus (ORFV) was amplified using published ORFVspecific primers by PCR. Morbidity and mortality were 100% and 3.3% respectively, while ORFV was detected by PCR. Diagnosis of Orf was confirmed based on clinical signs of enlarged lymph nodes, scabs on the mo...

Tropical animal health and production, Jan 30, 2014

Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. Ther... more Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. There are reports indicating the involvement of peste des petits ruminants virus (PPRV), the causative agent of PPR, in a camel respiratory syndrome in Africa. Considering that camels share the same grazing land and drinking points with other ruminants, this study was undertaken to determine the seroprevalence and extent of PPRV antibodies in Nigerian camels. A total of 1517 camel sera samples were collected from four states (Borno, Kano, Kastina and Sokoto). The seroprevalence was determined by the H-protein-based competitive ELISA. The overall prevalence was 3.36 % (51/1517, 95 % confidence interval of 2.51-4.39 %). There was no significant differences in prevalence between states (p = 0.8921) and between male and female camels (p = 0.7424). The prevalence differed significantly (p < 0.00001) by body condition score; camels with poor body condition score has higher (16.67 %) antibody se...

SUMMARY Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribut... more SUMMARY Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribution that can cause lethal disease in domestic dogs and other members of the family Canidae. Genetic diversity is found among reference strains and isolates of CDV, mainly in the haemagglutinin (H) protein, and this may be associated with the increasing incidence of distemper in dogs. CDV was isolated in Vero cells expressing canine signalling lymphocyte activation molecule (Vero.DogSLAM) from peripheral blood mononuclear cells and spleen of clinically diseased, previously vaccinated South African dogs. Direct fluorescence antibody test and electronmicroscopy were used to confirm the isolation procedure. Subsequently, RT-PCR was performed on the cell culture isolates, the amplified products were purified and the complete H gene was sequenced and phylogenetically analysed. The H gene of vaccines in use in South Africa was also sequenced and comparative analyses performed. However, the sequences obtained from the sick dogs showed 100% nucleotide identity and was different to that found in virus strains used in vaccines and in isolates reported from other parts of the world in GenBank. The results suggest that a novel CDV lineage may be present in South Africa and we conclude that a recent reversion of vaccine virus to virulence was not the cause of the clinical signs seen in dogs with a previous history of vaccination.

Foot-and-mouth-disease (FMD) is one of the most important trans-boundary animal diseases in Afric... more Foot-and-mouth-disease (FMD) is one of the most important trans-boundary animal diseases in Africa with outbreaks occurring mostly in cattle. However, there is scarcity of information on the potential role of camels in the epidemiology of FMD virus in West Africa. A total of 360 camel sera collected from abattoir in Nigeria from different geo-political zones (North, West and East) were screened for the presence of antibodies produced against 3ABC non-structural proteins (NSP) for foot-mouth-disease virus (FMDV) using a commercially available kit prioCHECK® FMDV NS. Thirty nine, (10.83%) out of the 360 sera samples were tested positive for 3ABC NSP ELISA. The 39 positive samples were further subjected for sero-typing using solid-phase competitive ELISA (SPCE) for antibodies to FMDV serotype A and O (Solid-Phase Competitive ELISA, IZSLER Brescia-Italy). Two out of the 39 sera samples were positive for serotype A and the remaining were negative for both serotype A and O. This appears to be the first report of evidence of FMD antibodies in dromedaries in West Africa and that dromedaries may be susceptible to FMDV infection.

Peste des petits ruminants, caused by the peste des petits ruminants virus (PPRV), is a highly co... more Peste des petits ruminants, caused by the peste des petits ruminants virus (PPRV), is a highly contagious and economically important transboundary viral disease of domestic and wild small ruminants and a major hindrance to small-ruminant production in Nigeria. The seroprevalence and distribution of PPRV antibodies in small ruminants in rural households,farms, live animal markets and slaughter slabs across the six different agro-ecological zones of Nigeria were determined. A total of 4548 serum samples from 3489 goats and 1059 sheep were collected in 12 states. A PPRV competitive enzyme-linked immunosorbent assay was used to test the samples and the data analysed with R statistical software version 3.0.1. The study animals included all ages and both sexes. The overall prevalence estimate of sera positive for PPRV antibodies was 23.16% (n = 1018 positive samples per 4548 total samples, 95% confidence interval: 21.79% – 24.57%). There were significant differences in the seroprevalence between the states ( p = 0.001). Taraba State had the highest seroprevalence of 29.51%, whilst the lowest seroprevalence of 14.52% was observed in Cross River State. There were no significant differences in the PPRV seroprevalence between male and female animals ( p = 0.571), age ( p = 0.323) and between species ( p = 0.639). These data indicate the current seroprevalence to PPRV in the small-ruminant population in Nigeria.

Archives of Veterinary Science, 2008

The antigenic properties of thirteen isolates of Newcastle disease virus were assessed against La... more The antigenic properties of thirteen isolates of Newcastle disease virus were assessed against La Śota strain. Using one of the previously recognized formulas significant antigenic differences were observed and marked inhibitory activities were noticed amongst the isolates and their hyper-immune sera as well as that of the La Śota strain. The implications of these differences for Newcastle disease epidemiology and control in Nigeria are discussed.

Veterinary Microbiology, 2014

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apol... more This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Veterinary Microbiology, 2014

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apol... more This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Archives of Veterinary Science, 2008

DogSLAM cells and its application to diagnosis

The aim of the study is to determine the epizootiology of Peste des petits ruminants (PPR) in Tur... more The aim of the study is to determine the epizootiology of Peste des petits ruminants (PPR) in Turkey during 2010-2012, using molecular genotyping. Samples of blood (n=193), swab (n=7) and tissue (n=374) were collected from sheep (n=473) and goats (n=101) suspected of having PPRV infection from an outbreak in 50 provinces of Turkey during 2010-2012. These samples (n=574) were tested using reverse transcription polymerase chain reaction (RT-PCR) and real-time reverse transcription polymerase chain reaction (RT-qPCR) targeting selected parts of the fusion (F) and the nucleocapsid (N) genes. Positivity ratios were 35.5%, 39.3%, and 44.4% with regards to RT-PCR targeting the F and the N genes, and RT-qPCR targeting the latter gene (N), respectively. The overall positivity rate was 45.8%. For sequence analyses, F-gene (n=53) and N-gene (n=60) positive samples representing different provinces were selected. After phylogenetic analysis, the circulating PPRV was located in lineage IV according to two gene regions. The F-gene partial sequence analysis at the nucleotide level showed 98.2-100% resemblence among 53 for F-gene, and 97.9-98.9% and 91.3-92.4% to Turkey2000 and Nigeria75/1 sequences, respectively. The N-gene partial sequence analysis at the nucleotide level showed 94.2-100% resemblence among 60 for N-gene, and 94.2-98.3% and 89.3-90.9% to Turkey2000 and Nigeria75/1 sequences, respectively. The result of this study indicates that PPRV infection is enzootic in Turkey, and belongs to the lineage IV, which is present in three haplogroup. The phylogenic analysis indicates the spread of the virus is associated with unauthorized movement of stock.

Veterinary Medicine and Science

Peste-des-petits-ruminants (PPR) and Goat pox (GTP) are two devastating and economically importan... more Peste-des-petits-ruminants (PPR) and Goat pox (GTP) are two devastating and economically important transboundary animal diseases of small ruminants in Africa and Asia that have been difficult to control. This study however, investigated an outbreak of PPR and GTP in a mixed flock of indigenous sheep and goats in Kanam, North Central Nigeria. A total of nine sera and seven tissues (lungs, spleen, scab and skin) samples were collected and analysed in the laboratory using competitive enzyme linked immunosorbent assay (cELISA) for PPR antibodies and polymerase chain reaction (PCR) for detection of PPR virus (PPRV) and GTP virus (GTPV). Gene fragments of the nucleoprotein of PPRV and the G-protein-coupled chemokine receptor (GPCR) of GTPV were amplified and sequenced to confirm the presence of the causative viruses. Serologically, antibodies to PPRV were detected in all (9/9) sera collected. GTPV and PPRV was detected in corresponding samples (42.8% n = 3/7) of the scab/skin samples collected by both PCR and RT-PCR technique. The phylogenetic analysis of PPRV revealed that the virus belongs to lineage IV and clustered with viruses from Gabon and Cameroon. Similarly, the GTPV also clustered with other sequences from Burkina Faso and Yemen. The positive cELISA, RT-PCR and PCR results from samples collected from the same animals confirmed co-infection of PPR and GTP in this mixed flock of sheep and goats. This is the first report of concurrent infection of PPR and GTP in mixed flock of sheep and goats in Nigeria. Our findings underscore the need for farmers to vaccinate their flock to control spread and economic losses as result of these diseases.

Open veterinary journal, 2018

Camel contagious ecthyma (CCE) is a viral disease of camelids that is caused by a Parapoxvirus (P... more Camel contagious ecthyma (CCE) is a viral disease of camelids that is caused by a Parapoxvirus (PPV) which is a DNA virus of the viral family: . Diseases affecting camels in Nigeria are scarcely reported. CCE or the laboratory detection of camel PPV (CPPV) has not been reported in Nigeria. This study investigated and described the clinical presentation of CCE and molecular detection of CPPV in Nigeria. Suspected cases of CCE were reported in a farm, live animal market and abattoir, in three different states (Bauchi, Plateau and Zamfara) in Northern Nigeria. Skin scabs, lungs, liver and intestine samples were collected. Polymerase chain reaction (PCR) was carried out using the primers which targets the RPO30 gene fragment of the genus PPV. The clinical signs observed from the suspected cases of CCE were proliferative skin lesions, papules, scabs on the lips and nares. CPPV was detected in 80.0% (4/5) of the samples collected by PCR. CCE was diagnosed based on clinical signs and PCR r...

Tropical Medicine and Infectious Disease

The aetiological agent of rabies is a member of the Lyssavirus genus (Rhabdoviridae family, order... more The aetiological agent of rabies is a member of the Lyssavirus genus (Rhabdoviridae family, order Mononegavirales). The disease (rabies) is endemic in many parts of Asia and Africa and still remains an important public and veterinary health threat. In Nigeria, there is a dearth of information on the natural infection and/or exposure of bat species to lyssaviruses. Therefore, this study was undertaken to assess the prevalence of rabies virus (RABV) neutralizing antibodies in sera obtained from bats from the central Plateau and North-East Bauchi States in Nigeria. Two hundred serum samples were collected from Nigerian fruit bats from six different locations and tested for anti-RABV antibodies using a commercial blocking ELISA. Of the 200 bat serum samples collected, one batch consisting of 111 samples did not meet the validation criteria and hence was not included in the final analysis. Of the remaining 89, only three (3.4%) contained anti-lyssavirus antibodies, demonstrating a low prevalence of lyssavirus antibodies in the study population. In order to further understand the exposure of bat species to phylogroup II lyssaviruses (Lagos bat virus and Mokola virus), the same panel of samples will be tested for neutralizing antibodies to phylogroup II members, viruses that do not cross-neutralize with members of phylogroup I.

African journal of infectious diseases, 2017

Sixty (60) male West African Dwarf goats were reported with clinical signs of enlarged lymph node... more Sixty (60) male West African Dwarf goats were reported with clinical signs of enlarged lymph nodes, scabs on the mouth, nose and ears. Two of the goats died and post mortem examination reveals enlarged submandibular lymph nodes and vesicular lesions on the tongue. Clinical diagnosis of Orf has been reported in Nigeria but this report is the confirmatory diagnosis of Orf in a suspected outbreak in an experimental farm in Uyo, Akwa Ibom State, Nigeria using molecular techniques. Scabs, spleen and lymph node samples from goats suspected to have died from Orf were collected, transported on ice to the laboratory and homogenized. The DNA was extracted using QIAmp DNA minikit (Qiagen) according to the manufacturer's instructions. Orf virus (ORFV) was amplified using published ORFVspecific primers by PCR. Morbidity and mortality were 100% and 3.3% respectively, while ORFV was detected by PCR. Diagnosis of Orf was confirmed based on clinical signs of enlarged lymph nodes, scabs on the mo...

Tropical animal health and production, Jan 30, 2014

Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. Ther... more Peste des petits ruminants (PPR), a viral disease of sheep and goats, is endemic in Nigeria. There are reports indicating the involvement of peste des petits ruminants virus (PPRV), the causative agent of PPR, in a camel respiratory syndrome in Africa. Considering that camels share the same grazing land and drinking points with other ruminants, this study was undertaken to determine the seroprevalence and extent of PPRV antibodies in Nigerian camels. A total of 1517 camel sera samples were collected from four states (Borno, Kano, Kastina and Sokoto). The seroprevalence was determined by the H-protein-based competitive ELISA. The overall prevalence was 3.36 % (51/1517, 95 % confidence interval of 2.51-4.39 %). There was no significant differences in prevalence between states (p = 0.8921) and between male and female camels (p = 0.7424). The prevalence differed significantly (p < 0.00001) by body condition score; camels with poor body condition score has higher (16.67 %) antibody se...

SUMMARY Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribut... more SUMMARY Canine distemper virus (CDV) is a highly contagious viral pathogen of worldwide distribution that can cause lethal disease in domestic dogs and other members of the family Canidae. Genetic diversity is found among reference strains and isolates of CDV, mainly in the haemagglutinin (H) protein, and this may be associated with the increasing incidence of distemper in dogs. CDV was isolated in Vero cells expressing canine signalling lymphocyte activation molecule (Vero.DogSLAM) from peripheral blood mononuclear cells and spleen of clinically diseased, previously vaccinated South African dogs. Direct fluorescence antibody test and electronmicroscopy were used to confirm the isolation procedure. Subsequently, RT-PCR was performed on the cell culture isolates, the amplified products were purified and the complete H gene was sequenced and phylogenetically analysed. The H gene of vaccines in use in South Africa was also sequenced and comparative analyses performed. However, the sequences obtained from the sick dogs showed 100% nucleotide identity and was different to that found in virus strains used in vaccines and in isolates reported from other parts of the world in GenBank. The results suggest that a novel CDV lineage may be present in South Africa and we conclude that a recent reversion of vaccine virus to virulence was not the cause of the clinical signs seen in dogs with a previous history of vaccination.

Foot-and-mouth-disease (FMD) is one of the most important trans-boundary animal diseases in Afric... more Foot-and-mouth-disease (FMD) is one of the most important trans-boundary animal diseases in Africa with outbreaks occurring mostly in cattle. However, there is scarcity of information on the potential role of camels in the epidemiology of FMD virus in West Africa. A total of 360 camel sera collected from abattoir in Nigeria from different geo-political zones (North, West and East) were screened for the presence of antibodies produced against 3ABC non-structural proteins (NSP) for foot-mouth-disease virus (FMDV) using a commercially available kit prioCHECK® FMDV NS. Thirty nine, (10.83%) out of the 360 sera samples were tested positive for 3ABC NSP ELISA. The 39 positive samples were further subjected for sero-typing using solid-phase competitive ELISA (SPCE) for antibodies to FMDV serotype A and O (Solid-Phase Competitive ELISA, IZSLER Brescia-Italy). Two out of the 39 sera samples were positive for serotype A and the remaining were negative for both serotype A and O. This appears to be the first report of evidence of FMD antibodies in dromedaries in West Africa and that dromedaries may be susceptible to FMDV infection.

Peste des petits ruminants, caused by the peste des petits ruminants virus (PPRV), is a highly co... more Peste des petits ruminants, caused by the peste des petits ruminants virus (PPRV), is a highly contagious and economically important transboundary viral disease of domestic and wild small ruminants and a major hindrance to small-ruminant production in Nigeria. The seroprevalence and distribution of PPRV antibodies in small ruminants in rural households,farms, live animal markets and slaughter slabs across the six different agro-ecological zones of Nigeria were determined. A total of 4548 serum samples from 3489 goats and 1059 sheep were collected in 12 states. A PPRV competitive enzyme-linked immunosorbent assay was used to test the samples and the data analysed with R statistical software version 3.0.1. The study animals included all ages and both sexes. The overall prevalence estimate of sera positive for PPRV antibodies was 23.16% (n = 1018 positive samples per 4548 total samples, 95% confidence interval: 21.79% – 24.57%). There were significant differences in the seroprevalence between the states ( p = 0.001). Taraba State had the highest seroprevalence of 29.51%, whilst the lowest seroprevalence of 14.52% was observed in Cross River State. There were no significant differences in the PPRV seroprevalence between male and female animals ( p = 0.571), age ( p = 0.323) and between species ( p = 0.639). These data indicate the current seroprevalence to PPRV in the small-ruminant population in Nigeria.

Archives of Veterinary Science, 2008

The antigenic properties of thirteen isolates of Newcastle disease virus were assessed against La... more The antigenic properties of thirteen isolates of Newcastle disease virus were assessed against La Śota strain. Using one of the previously recognized formulas significant antigenic differences were observed and marked inhibitory activities were noticed amongst the isolates and their hyper-immune sera as well as that of the La Śota strain. The implications of these differences for Newcastle disease epidemiology and control in Nigeria are discussed.

Veterinary Microbiology, 2014

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apol... more This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

Veterinary Microbiology, 2014

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apol... more This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.