A seroepidemiological study of bovine cysticercosis in Bali and Nusa Tenggara, Indonesia.

BACKGROUND AND AIM: Taenia saginata hazardously affects human and animal health. The distribution of this disease is found almost all over the world. The study aimed to obtain epidemiological information concerning prevalence and the distribution of bovine cysticercosis in Bali and Nusa Tenggara, Indonesia. MATERIALS AND METHODS: A total of 267 community-owned Bali cattle serum samples from the provinces of Bali, West Nusa Tenggara, and East Nusa Tenggara were examined. The study was conducted by examining the serum of Bali cattle using enzyme-linked immunosorbent assay technique. Risk factors related to cysticercosis that analyzed were sex, breeding type, age, physical condition, source of drinking water, pen condition, and latrine availability. RESULTS: Seven of 91 Bali cattle sera from all regencies/cities in Bali showed a positive result. Those positive sera were originated from Buleleng (1), Gianyar (2), Denpasar (2), and Klungkung (2). Meanwhile, four of 92 Bali cattle sera from West Nusa Tenggara and seven of 84 from East Nusa Tenggara occurred antibodies against T. saginata. We identified that two risk factors that influence the incidence of T. saginata infection in Bali cattle in Bali were the sex and the cattle breeding type. CONCLUSION: Through this research can be made a map of bovine cysticercosis in Bali cattle in Bali and Nusa Tenggara region. By mapping the disease, it is recommended that the animal health officers should be more accurate when conducting postmortem examination, especially on cattle from a positive region.

Seroprevalence of Neospora caninum in local Bali dog.

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.

Reducing zoonotic and internal parasite burdens in pigs using a pig confinement system.

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.

Achieving population-level immunity to rabies in free-roaming dogs in Africa and Asia.

Canine rabies can be effectively controlled by vaccination with readily available, high-quality vaccines. These vaccines should provide protection from challenge in healthy dogs, for the claimed period, for duration of immunity, which is often two or three years. It has been suggested that, in free-roaming dog populations where rabies is endemic, vaccine-induced protection may be compromised by immuno-suppression through malnutrition, infection and other stressors. This may reduce the proportion of dogs that seroconvert to the vaccine during vaccination campaigns and the duration of immunity of those dogs that seroconvert. Vaccination coverage may also be limited through insufficient vaccine delivery during vaccination campaigns and the loss of vaccinated individuals from populations through demographic processes. This is the first longitudinal study to evaluate temporal variations in rabies vaccine-induced serological responses, and factors associated with these variations, at the individual level in previously unvaccinated free-roaming dog populations. Individual-level serological and health-based data were collected from three cohorts of dogs in regions where rabies is endemic, one in South Africa and two in Indonesia. We found that the vast majority of dogs seroconverted to the vaccine; however, there was considerable variation in titres, partly attributable to illness and lactation at the time of vaccination. Furthermore, >70% of the dogs were vaccinated through community engagement and door-to-door vaccine delivery, even in Indonesia where the majority of the dogs needed to be caught by net on successive occasions for repeat blood sampling and vaccination. This demonstrates the feasibility of achieving population-level immunity in free-roaming dog populations in rabies-endemic regions. However, attrition of immune individuals through demographic processes and waning immunity necessitates repeat vaccination of populations within at least two years to ensure communities are protected from rabies. These findings support annual mass vaccination campaigns as the most effective means to control canine rabies.

The demography of free-roaming dog populations and applications to disease and population control.

1. Understanding the demography of domestic dog populations is essential for effective disease control, particularly of canine-mediated rabies. Demographic data are also needed to plan effective population management. However, no study has comprehensively evaluated the contribution of demographic processes (i.e. births, deaths and movement) to variations in dog population size or density, or determined the factors that regulate these processes, including human factors. 2. We report the results of a 3-year cohort study of domestic dogs, which is the first to generate detailed data on the temporal variation of these demographic characteristics. The study was undertaken in two communities in each of Bali, Indonesia and Johannesburg, South Africa, in rabies-endemic areas and where the majority of dogs were free-roaming. None of the four communities had been engaged in any dog population management interventions by local authorities or animal welfare organizations. All identified dogs in the four communities were monitored individually throughout the study. 3. We observed either no population growth or a progressive decline in population size during the study period. There was no clear evidence that population size was regulated through environmental resource constraints. Rather, almost all of the identified dogs were owned and fed regularly by their owners, consistent with population size regulated by human demand. Finally, a substantial fraction of the dogs originated from outside the population, entirely through the translocation of dogs by people, rather than from local births. These findings demonstrate that previously reported growth of dog populations is not a general phenomenon and challenge the widely held view that free-roaming dogs are unowned and form closed populations. 4.Synthesis and applications. These observations have broad implications for disease and population control. The accessibility of dogs for vaccination and evaluation through owners and the movement of dogs (some of them infected) by people will determine the viable options for disease control strategies. The impact of human factors on population dynamics will also influence the feasibility of annual vaccination campaigns to control rabies and population control through culling or sterilization. The complex relationship between dogs and people is critically important in the transmission and control of canine-mediated rabies. For effective management, human factors must be considered in the development of disease and population control programmes.

Seroprevalence of antibodies to Neospora caninum in Bos javanicus ('Bali cattle') from Indonesia.

A cross-sectional survey was performed to obtain first information on the presence of Neospora caninum infection in Bos javanicus ('Bali cattle'), the predominant beef cattle in the Eastern Islands of Indonesia. Serum samples were collected from 438 Bali cattle of two age classes (<2 years, >2 years) and both genders at three slaughterhouses in the Bali island, and examined for N. caninum-specific antibodies using native NcSRS2 (p38 antigen) as an ELISA antigen. The estimated overall seroprevalence of antibodies was 5.5% (95% CI: 3.5-8.0%). The seroprevalence was not significantly associated with age class or gender of the animals. The results give first serological evidence for the presence of natural N. caninum infection in Bos javanicus and indicate its occurrence in Indonesia.

Prevalence and age-dependent occurrence of intestinal protozoan infections in suckling piglets.

A cross-sectional survey was performed on 20 pig breeding farms in southern Hesse, central Germany, to evaluate the prevalence and age-dependent occurrence of intestinal protozoan parasites in unweaned piglets. Faecal samples of 514 clinically unaffected piglets of different age (< 1 to 5-7 weeks) were examined using the sodium acetate-acetic acid-formalin (SAF) concentration technique. Infections with the following protozoan species were detected: Balantidium coli (16 of 20 farms), Entamoeba sp. (15), Jodamoeba sp. (14), Isospora (I.) suis (9), Chilomastix sp. (6) and Eimeria spp. (6). The protozoan species differed in the start and course of (oo)cyst excretion. I. suis oocysts and Jodamoeba cysts were detected already in the first week of life whereas shedding of the other parasites started later on. The prevalence of Isospora oocyst excretion increased to a maximum (18%) in 2-3 weeks old animals followed by a sharp decline. The proportion of Balantidium, Entamoeba or Jodamoeba positive suckling piglets continously increased until the age of 5-7 weeks to 60%, 52% and 22%, respectively, whereas that of Chilomastix positive animals remained on a low level of 8-12% independent of the age. Eimeria oocysts were found transiently in the faeces of 1-4 weeks old piglets.

Small strongyle infection: consequences of larvicidal treatment of horses with fenbendazole and moxidectin.

The study was undertaken to evaluate adverse effects of larvicidal treatment in horses naturally infected with cyathostomins. Out of 24 ponies kept on pasture, four animals were housed in September and anthelmintically cured to serve as worm-free controls (group C-0). The others were housed in December. Eight animals each were treated 8 weeks later with 5 x 7.5mg/kg fenbendazole (FBZ) or 1 x 0.4 mg/kg moxidectin (MOX). Four animals remained untreated (group C-i). Two, 4, 6 and 14 days after the end of treatment two animals of each of the treated groups were necropsied together with group C-0 and C-i animals. Infected animals before treatment showed weight loss, eosinophilia, increased plasma protein and globulin contents. Treatment was followed by weight gain and temporal plasma protein and globulin increase. Proportions of CD4+ and CD8+ T lymphocytes in the peripheral blood did not differ between the groups before treatment but dropped significantly temporally after FBZ treatment. Group C-0 was worm-free at necropsy. Group C-i animals contained variable numbers of luminal and tissue cyathostomins. Histological sections showed larval stages in the lamina propria und submucosa surrounded by macrophages. Either treatment was effective against luminal parasites and reduced the number of larvae in the bowel wall beginning 4-6 days after FBZ and 6-14 days after MOX treatment. Histologically, as a first reaction after FBZ application T lymphocytes accumulated around morphologically intact L4 in the submucosa. Subsequently T lymphocytes associated with eosinophils infiltrated the submucosa. Parasites became enclosed by granulomas with eosinophils adhering to and invading the larvae which started to disintegrate on day 4. Later on, particularly on day 14 inflammation extended into the mucosa and was frequently associated with ulcerations. Third stage larvae in general and L4 in the lamina propria, however, seemed not to be affected until day 14 and even then, parasites did usually not generate extensive inflammation. After MOX treatment severe morphologically detectable alterations of tissue larvae could not be observed earlier than day 14. Different from FBZ treatment, larvae disintegrated and were obviously resorbed without causing severe inflammation in the gut wall. In conclusion treatment with either drug was efficacious against tissue larvae of cyathostomins but there may be different clinical consequences: in contrast to MOX effects, killing of larvae due to FBZ was associated with severe tissue damage, which clinically may correspond to reactions caused by synchronous mass emergence of fourth stage larvae, i.e., may mimic larval cyathostominosis.