Molecular characterization of African swine fever virus in apparently healthy domestic pigs in Uganda

African swine fever (ASF) is a highly lethal and economically significant disease of domestic pigs in Uganda where outbreaks regularly occur. There is neither a vaccine nor treatment available for ASF control. Twenty two African swine fever virus (ASFV) genotypes (I - XXII) have been identified based on partial sequencing of the C-terminus of the major capsid protein p72 encoded by the B646L gene. The majority of previously characterized Ugandan ASFV strains belong to genotype IX. The major aim of the current study was to determine the ASFV genotypes among asymptomatic slaughter pigs at Wambizi slaughterhouse and in some parts of the country where surveillance was done. Three discrete regions of the ASFV were analysed in the genomes of viruses detected in asymptomatic domestic pigs. The analysis was conducted by genotyping based on sequence data from three single copy ASFV genes. The E183L gene encoding the structural protein P54 and part of the gene encoding the p72 protein were used to delineate genotypes, before intra-genotypic resolution of viral relationships by analysis of tetramer amino acid repeats within the hypervariable central variable region (CVR) of the B602L gene. All the ASF viruses obtained from this study clustered with previous viruses in genotype IX based on analysis of the p72 and P54 genes. Analysis of the CVR gene grouped the viruses in three different subgroups; 13, 23 and 25. Only one genotype is circulating in Uganda among asymptomatic domestic pigs and it is the same virus causing outbreaks in the country and parts of neighbouring Kenya.Keywords: African swine fever virus, asymptomatic, slaughterhouse, P54, p72, CVR gene, genotypesAfrican Journal of Biotechnology, Vol 13(25)2491-249

Frontal abscess in a Friesian bull in Kampala Uganda: A case report

No Abstract. Bulletin of Animal Health and Production in Africa Vol. 50 (2) 2002: pp. 135-13

Isolation of Mycobacterium avium subspecies paratuberculosis from Ugandan cattle and strain differentiation using optimised DNA typing techniques

BACKGROUND: The occurrence of paratuberculosis in Ugandan cattle has recently been reported but there is no information on the strains of Mycobacterium avium subspecies paratuberculosis (MAP) responsible for the disease. The aim of this study was to isolate and characterise MAP from seropositive cattle and paratuberculosis lesions in tissues obtained from slaughtered cattle in Uganda. RESULTS: Twenty one isolates of MAP were differentiated into 11 genotype profiles using seven genotyping loci consisting of Insertion Sequence 1311(IS1311), Mycobacterial interspersed repeat units (MIRU) (loci 2, 3), Variable number tandem repeats (VNTR) locus 32 and Short sequence repeats (SSR) (loci 1, 2 and 8). Three different IS1311 types and three MIRU 2 profiles (7, 9, 15 repeats) were observed. Two allelic variants were found based on MIRU 3 (1, 5 repeats), while VNTR 32 showed no polymorphism in any of the isolates from which it was successfully amplified. SSR Locus 1 revealed 6 and 7 G1 repeats among the isolates whereas SSR locus 2 revealed 10, 11 and 12 G2 repeats. SSR locus 8 was the most polymorphic locus. Phylogenetic analysis of SSR locus 8 sequences based on their single nucleotide polymorphisms separated the isolates into 8 genotypes. We found that the use of Ethylene glycol as a PCR additive improved the efficiency of the PCR reactions for MIRUs (2, 3), VNTR 32 and SSR (loci 1 and 2). CONCLUSIONS: There is a high strain diversity of MAP in Uganda since 21 isolates could be classified into 11 genotypes. The combination of the seven loci used in this study results into a very precise discrimination of isolates. However analysis of SNPs on locus alone 8 is very close to this combination. Most of the genotypes in this study are novel since they differed in one or more loci from other isolates of cattle origin in different studies. The large number of MAP strains within a relatively small area of the country implies that the epidemiology of paratuberculosis in Uganda may be complicated and needs further investigation. Finally, the use of Ethylene glycol as a PCR additive increases the efficiency of PCR amplification of difficult templates

Haematological, biochemical and clinical changes in domestic pigs experimentally infected with african swine fever virus Isolates from Uganda

African swine fever (ASF) is a highly contagious often fatal viral disease of pigs caused by asfivirus. The disease causes marked leucopaenia, depletion of lymphocytes in the lymphoid tissues, changes in biochemical parameters, haemorrhages and necrosis in multiple organs of the infected pigs. We studied the pathogenic effect of three different Ugandan ASF virus (ASFV) isolates on twelve infected and six uninfected pigs. Each pig in the infected group was inoculated per os with 2 mls of ASFV culture solution containing 1X 108 H.A.D.U/ml of the viral culture solution while the control group were given 2 mls of uninfected porcine alveolar macrophages culture per-os. Clinical parameters were monitored daily and blood samples collected for leucocytes count and biochemical tests. In the present study, the incubation period of the disease ranged from 7 - 15 days and in average the clinical disease lasted for 5 days. On the eighth day post infection, all test pigs had significant leucopaenia (p = 0.000) and number of lymphocytes reduced significantly (p =0.001,). Band neutrophils progressively increased in number as the disease progressed, however when the changes in mean band neutrophils in the three groups were compared it was not statistically significant (p= 0.52). There were no significant variations in the mean basophils and eosinophil counts in all experimental groups during study period (p = 0.30 and p = 0.32 respectively). Nevertheless, mean monocytes counts significantly increased in infected pigs (p = 0.01), while in uninfected group there was no significant variation in the mean monocytes counts. The majority of the pigs, 83.3% (n = 10) in the test groups had elevated levels of gamma-glutamyl transferase (GGT). The Level of Alanine Amino Transferase (ALT) at 8 days post infection was elevated in all infected pigs in the three groups. In 66.7% (n = 8) infected pigs, Albumin (ALB) levels were elevated in the serum samples above the normal range of 18 – 33 g/l. The levels of other biochemicals in the serum samples such as Creatine kinase (CK), Creatinine (CREA), and Alkaline Phosphatase (ALKP) remained within the normal range (50- 3531 μ/L, 44 -186μmol/L, 92 - 294 μ/L, respectively). We concluded that ASF causes significant deviation in leucocytes counts, increased levels of GGT, ALT and ALB and clinical parameters in pigs infected with Ugandan isolates of ASF virus.Key words: African swine fever (ASF), Domestic pigs Haematological, biochemical and clinical parameter

Haematological, biochemical and clinical changes in domestic pigs experimentally infected with african swine fever virus Isolates from Uganda

African swine fever (ASF) is a highly contagious often fatal viral disease of pigs caused by asfivirus. The disease causes marked leucopaenia, depletion of lymphocytes in the lymphoid tissues, changes in biochemical parameters, haemorrhages and necrosis in multiple organs of the infected pigs. We studied the pathogenic effect of three different Ugandan ASF virus (ASFV) isolates on twelve infected and six uninfected pigs. Each pig in the infected group was inoculated per os with 2 mls of ASFV culture solution containing 1X 108 H.A.D.U/ml of the viral culture solution while the control group were given 2 mls of uninfected porcine alveolar macrophages culture per-os. Clinical parameters were monitored daily and blood samples collected for leucocytes count and biochemical tests. In the present study, the incubation period of the disease ranged from 7 - 15 days and in average the clinical disease lasted for 5 days. On the eighth day post infection, all test pigs had significant leucopaenia (p = 0.000) and number of lymphocytes reduced significantly (p =0.001,). Band neutrophils progressively increased in number as the disease progressed, however when the changes in mean band neutrophils in the three groups were compared it was not statistically significant (p= 0.52). There were no significant variations in the mean basophils and eosinophil counts in all experimental groups during study period (p = 0.30 and p = 0.32 respectively). Nevertheless, mean monocytes counts significantly increased in infected pigs (p = 0.01), while in uninfected group there was no significant variation in the mean monocytes counts. The majority of the pigs, 83.3% (n = 10) in the test groups had elevated levels of gamma-glutamyl transferase (GGT). The Level of Alanine Amino Transferase (ALT) at 8 days post infection was elevated in all infected pigs in the three groups. In 66.7% (n = 8) infected pigs, Albumin (ALB) levels were elevated in the serum samples above the normal range of 18 – 33 g/l. The levels of other biochemicals in the serum samples such as Creatine kinase (CK), Creatinine (CREA), and Alkaline Phosphatase (ALKP) remained within the normal range (50- 3531 μ/L, 44 -186μmol/L, 92 - 294 μ/L, respectively). We concluded that ASF causes significant deviation in leucocytes counts, increased levels of GGT, ALT and ALB and clinical parameters in pigs infected with Ugandan isolates of ASF virus.Key words: African swine fever (ASF), Domestic pigs Haematological, biochemical and clinical parameter