ABSTRACT
Background and Aims: Despite the endemicity of Japanese encephalitis virus (JEV) in humans and animals in the Province of Bali, Indonesia, there is little data on whether seroconversion to the virus occurs in pigs, JEV genotypes circulating, and it's potential mosquito vectors in the area. The aims of this study were to (i) Determine whether JEV infection in Balinese pigs occurs before reaching their sexual maturity, (ii) identify the genotypes of circulating JEV, and (iii) identify potential JEV mosquito vectors at the study sites in urban and peri-urban areas of Bali. Materials and Methods: Sixteen 1-week-old Landrace piglets from two different sows were housed in Denpasar. Similarly, 18 one-week-old mixed-breed piglets of two different sows were housed in Badung Regency. The piglets were bled every 1 to 4 weeks for up to 24 weeks. Serum samples from the 11 piglets were tested for antibodies against JEV, and seroconversion-suspected sera were titrated using an enzyme-linked immunosorbent assay. Blood of seroconverted sera from pigs were tested using polymerase chain reaction (PCR) to detect the genetic sequence of JEV. The mosquitoes in the sentinels were trapped throughout the study period to identify the potential mosquito vectors of JEV. Results: Antibodies were detected in most of the selected piglets' sera from weeks 1 to 24 of their age. However, sera of pig B9 collected from the sentinel setting in Badung Regency showed a four-fold increase in antibody titer from week 4 to week 8, indicating seroconversion. PCR testing of blood from B9 (pooled blood sample collected from week 5 to week 8) identified JEV nucleic acids, which were phylogenetically classified as belonging to the JEV genotype III. Meanwhile, 1271 of two genera of mosquitoes, Anopheles spp. and Culex spp. were trapped in the pig sentinels. Conclusion: JEV seroconversion likely occurs before the pig reaches sexual maturity in Badung Regency. Sequence data indicate that JEV genotype III is circulating in the pig sentinel setting in the regency; however, circulating genotypes need to be clarified through increased surveillance. Meanwhile, Culex spp. and most likely Culex quinquefasciatus and Anopheles spp. were the dominant mosquitoes present in the study sites set in the urban area of Denpasar and peri-urban areas of Badung, Bali, indicating that these are likely vectors in spread of JEV in the region.
ABSTRACT
BACKGROUND AND AIM: Several free-roaming dogs can be easily found in the public areas of Bali. They go out in search of foods and friends and defecate everywhere. In general, these groups of dogs do not receive good healthcare from their owners and are generally threatened by some disease-causing organisms, especially helminths. This study was conducted to identify and measure the prevalence of soil-transmitted helminths (STHs) that cause infection in free-roaming dogs in Bali Province, Indonesia. MATERIALS AND METHODS: A total of 1611 fresh dog fecal samples were collected from all areas of Bali Province and subjected to qualitative fecal examination using flotation techniques to obtain STH eggs. RESULTS: The incidence of STHs in free-roaming dogs was 38.36%. However, three types of STHs were identified, including Ancylostoma spp., Ascaris spp., and Trichuris spp. Ancylostoma spp. had the highest prevalence of 37.8%, followed by Ascaris spp. and Trichuris spp. at 6.02% and 0.87%, respectively. Multiple infections of these worms were also recorded. The polyparasitism prevalence of Ancylostoma spp. and Ascaris spp. was 3.85%, followed by that of Ancylostoma spp. and Trichuris spp. at 0.5% and that of Ascaris spp. and Trichuris spp. at 0.06%. There were no altitude-wise differences in the prevalence of STH infection. CONCLUSION: The prevalence of STHs was high in free-roaming dogs. This finding necessitates more serious attention as it affects both animal and public health.
ABSTRACT
BACKGROUND AND AIM: Immunoglobulin (Ig) G1 and IgG2a are the surrogate markers respectively for humoral and cellular immune responses of hosts against antigens including cystic fluid proteins of Cysticercus bovis. A study was conducted to investigate the IgG1 and IgG2a responses of Balb/c mice against some individual cystic fluid proteins of C. bovis in an effort to determine the roles of each protein in inducing the humoral and cellular immune responses in host. MATERIALS AND METHODS: Individual p71, p31, and p14 proteins of C. bovis were purified by separation of the proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and elution of individual proteins from the gel. Six female Balb/c mice were immunized 4 times at 10-day intervals with the crude cystic fluid proteins, and sera were collected for the measurement of IgG1 and IgG2a levels against the individual proteins. Sera samples collected before the first immunization were used as negative antibody control, sera samples collected after the fourth immunization were used as positive antibody control, and crude cystic fluid protein was used as positive antigen control. RESULTS: All immunized mice were immune to p71, p31, p14, and crude cystic fluid proteins of C. bovis. The crude cystic fluid proteins of C. bovis induced a higher IgG2a than IgG1 level following the first and the second immunizations but switched into a higher IgG1 than IgG2a level following the fourth immunization. Protein 71 kDa (p71) induced a higher IgG2a than IgG1 level following the fourth immunization. In contrast, p14 induced a higher IgG1 than IgG2a level following the fourth immunization. Low and balance IgG1 and IgG2a levels against p31 were observed following the first to the fourth immunizations. CONCLUSION: Using IgG1 and IgG2a levels as the surrogate markers, it appears that cystic fluid antigens of C. bovis induce both humoral and cellular immune responses in Balb/c mice. The p71 appears to be a better inducer of cellular immune response, whereas p14 is a better inducer of humoral immune response of mice.
ABSTRACT
AIM: The aim of this research was to identify the seroprevalence of Neospora caninum in local Bali dogs. MATERIALS AND METHODS: A total of 147 local Bali dog serum samples have been examined for antibodies of N. caninum using enzyme-linked immunosorbent assay test. RESULTS: The results confirmed that 5 (3.4%) local Bali dogs have antibody for N. caninum. There were no significant differences in seroprevalence of Neospora infection in local Bali dogs between different genders, ages, and take care methods (p>0.05). CONCLUSION: The results provided evidence for the presence of N. caninum infection in local Bali dogs and thus the risk to Bali cattle and dog health.
ABSTRACT
AIM: This study was designed to validate the effectiveness of the pig confinement system (PCS) in reducing the prevalence of zoonotic and internal parasite burdens in pigs. MATERIALS AND METHODS: Ten PCS households were selected together with 10 households practising traditional scavenging systems. Five pigs were monitored per household every 3 months for 15 months and blood and feces collected. Pigs received a single dose of oxfendazole at 30 mg/kg at baseline. Qualitative fecal examinations for intestinal parasite stages were performed, and serum was tested for antibodies to cysticercus of Taenia solium, Trichinella spp., and Toxoplasma gondii. RESULTS: Based on fecal examination, the prevalence of pigs positive for parasite eggs was reduced in PCS pigs over consecutive samplings (Ascaris suum [14.3% to 0%], Trichuris suis [46.9% to 8.3%], Strongyle-type eggs [81.6% to 8.3%], Physocephalus spp. [6.1% to 0%], and Metastrongylus apri [20.8% to 0%]) compared with increases in the number of pigs positive for parasite eggs in non-PCS pigs (T. suis [20-61.5%], Strongyle-type [60.4-80.8%], Physocephalus spp. [8.3-15.4%], and M. apri [20.8-34.6%]) and little change in pigs positive for A. suum (18.8-19.2%). While the prevalence of pigs with antibodies against to cysticerci of T. solium reduced in PCS pigs from 18% to 14%, the prevalence in non-PCS pigs increased from 42% to 52%. Antibodies to Trichinella were not detected, but the prevalence of T. gondii antibodies increased from 6% to 10% in PCS pigs and from 7% to 24% in non-PCS pigs. CONCLUSION: These data demonstrate the potential of a PCS to reduce the prevalence of pigs infected with zoonotic and internal parasites and thus the risk to human and pig health.
