Efficacy of bivalent fimbrial vaccines to control and eliminate intermediate forms of footrot in sheep.

OBJECTIVE: The aim of this study was to determine the efficacy of serogroup-specific bivalent fimbrial vaccines in the control and elimination of relatively mild (intermediate) forms of footrot in sheep flocks in NSW, there being some evidence that such forms are difficult to control. METHODS: Four flocks of sheep with history of footrot of intermediate virulence were selected based on clinical and bacteriological diagnoses. Dichelobacter nodosus serogroups included in bivalent vaccines at each farm were based on on-farm serogroup-prevalence data. Two doses of bivalent vaccine were administered with a 4-week interval between doses. Repeated post-vaccination inspections of all feet of between 100 and 119 animals per mob were conducted and foot swabs were collected for bacteriological testing. Blood samples were collected from 10 to 24 individually identified animals per flock at each inspection to check for agglutinating antibody responses. RESULTS: In the majority of animals, antibody levels for serogroups included in each vaccine were above the level believed to be required for protective immunity. Footrot disappeared on farm 1 prior to vaccination, but did not reappear postvaccination. Footrot was controlled but not eliminated on farms 2, 3, and 4, where the prevalence and severity of the disease and number of serogroups present were reduced. CONCLUSION: Serogroup-specific bivalent vaccines can be effective at controlling footrot caused by intermediate strains of D. nodosus.

Continuity in ovine Johne's disease vaccination practices despite a decline in clinical disease.

The Gudair® vaccine has been commercially available in Australia for almost two decades for the control of ovine Johne's disease, but concerns have been raised about potential discontinuation of vaccination by producers after a decline in the incidence of clinical disease. An online questionnaire was distributed to Australian sheep producers to identify the proportion of respondents discontinuing the Gudair vaccine and reasons for discontinuation. Results revealed that 88% of sheep producers surveyed have continued to vaccinate their sheep with Gudair, with continuation greater for predominantly Merino sheep flocks. Reasons for discontinuing vaccination stemmed from management, economic or health concerns. These results suggest that Gudair is still widely used by Australian sheep producers and concerns about large-scale discontinuation are unfounded. These findings have implications for ovine Johne's disease control programs in Australia.

The severity of footrot lesions induced by aprV2-positive strains of Dichelobacter nodosus varies between strains.

OBJECTIVES: The primary objective of this study was to evaluate the clinical virulence of aprV2-positive lesser virulent field isolates of footrot bacteria Dichelobacter nodosus in comparison with an aprV2-positive clinically virulent reference strain. Correlations between the clinical expression of the disease and the presence of aprV2 (detected using PCR tests) have been inconsistent. A second objective was to evaluate the elimination of D. nodosus following treatment of sheep as some strains of D. nodosus have been reported to be difficult to eliminate. METHODS: The virulence of three aprV2-positive field isolates of D. nodosus which had lesser virulent phenotypes, and an aprV2-positive virulent reference strain was evaluated in a sheep trial using a pasture-based experimental infection model. In the second phase of the study, treatments including footbathing and a long-acting antibiotic were administered and their efficacy in elimination of these strains was evaluated. RESULTS: Severe underrun (score 4) lesions developed in sheep infected with the aprV2-positive virulent reference strain but not in sheep infected with the field isolates; they had mild lesions (score 2 or 3). The three field isolates and the virulent reference strain of D. nodosus were eliminated by intensive foot bathing and antibiotic therapy in combination with housing the animals in dry conditions post-treatment. CONCLUSION: The results suggest that the presence of aprV2 gene in isolates of D. nodosus may not be a reliable indicator of virulence and that further investigation of the factors that determine clinical virulence is required. While the treatment regime was successful, based on a range of considerations, the use of such an intensive treatment involving antibiotics should be limited to small groups of high-value animals, such as rams.

A survey of ewe mortality on the Central Tablelands of New South Wales in 2010, a year of above-average rainfall.

BACKGROUND: Sheep producers reported elevated ewe mortality following a wetter-than-average season on the tablelands of New South Wales in 2010. We conducted a survey of local producers to determine the extent and cause of ewe losses, as well as associated risk factors. METHODS: A questionnaire was designed and posted to sheep producers running at least 1000 sheep. Data from questionnaires were analysed using linear mixed models to identify risk factors associated with ewe mortality. Data on the likely causes of deaths, particularly those associated with foot abscess, were analysed by ordinal generalised linear mixed models to determine the most prevalent causes of ewe death. RESULTS: The mean annual ewe mortality was 5.4% (range 0.1%-28.6%). Higher mortality was associated with older ewes and lambing in paddocks with longer pastures. The two most important causes of ewe death reported by farmers were 'died during lambing' and 'foot abscess'. Mortality due to foot abscess was more commonly reported in adult ewes than maiden ewes (odds ratio and 95% confidence interval: 5.61; 3.52, 8.94), when lambing on pasture longer than 5 cm than ≤5 cm (2.96; 1.54, 5.70) and when lambing in spring than in autumn (4.87; 1.36, 17.41). CONCLUSIONS: The level of ewe mortality observed was at the upper end of that reported previously in Australia. Risk factor analysis suggested that, in wet years, losses due to foot abscess could be reduced by lambing older heavier ewes in autumn on pasture swards less than 5 cm high.

Identification of risk factors associated with Coxiella burnetii infection in cattle and buffaloes in India.

The etiological agent Coxiella burnetii is a highly infectious gram-negative bacterium that can affect multiple species. Many reports confirm its presence in humans, domestic ruminants and rodents in India. This study was aimed to investigate the risk factors associated with C. burnetii infection in bovine populations in Punjab, India. This study was conducted using a stratified two-stage random sampling approach. Twenty-two villages representing all districts of the state were selected. Bovine farmers were interviewed and detailed information about their management and husbandry practices was collected using a structured questionnaire. Blood, milk and genital swab samples were collected from the cattle and buffaloes owned by the farmers. An animal was declared C. burnetii infected by using a combination of tests in parallel, i.e. if it was positive in serological or molecular tests (IgG indirect ELISA or Trans-PCR assay). A herd was considered positive if at least one animal in the herd was declared C. burnetii infected using the above definition. Three binomial logistic regression models were constructed to evaluate the association of (a) geographical location, herd characteristics, and farm management practices with the herd status (herd model), (b) individual animal related factors with the C. burnetii infection status (individual animal model), and (c) production and health related factors with C. burnetii infection status in adult females (adult female model). We collected a total of 610 blood, 610 genital swabs and 361 milk samples from 378 cattle and 232 buffaloes in 179 herds/households. The practice of throwing away aborted materials outside the farm as compared to burial/burning (adjusted odds ratio [OR] 3.0, 95 % confidence interval [CI] 1.14-7.87, p = 0.02) was associated with larger odds of being a C. burnetii infected herd. On the other hand, separation of the animals from the rest of the herd during parturition had a protective effect for being a C. burnetii infected herd (adjusted OR 0.31, 95 % CI 0.18-0.77, p = 0.01). Being cattle as compared to buffalo (adjusted OR 3.37, 95 % CI 1.23-9.20, p = 0.02) and older (adjusted OR 3.37, 95 % CI 1.23-9.20, p = 0.02) were associated with larger odds of C. burnetii infection. The current study highlights that farm practices such as improper aborted material disposal and not separating the animals from the rest of the herd during parturition are important risks for the occurrence of C. burnetii infection in the bovine populations in the state.

The immunogenicity and tissue reactivity of Mycobacterium avium subsp paratuberculosis inactivated whole cell vaccine is dependent on the adjuvant used.

Johne's disease (JD) is a chronic enteritis caused by Mycobacterium avium subspecies paratuberculosis (MAP). Current commercial vaccines are effective in reducing the occurrence of clinical disease although vaccinated animals can still become infected and transmit MAP. Many vaccinated sheep develop severe injection site lesions. In this study a range of adjuvants (Montanide TM ISA 50V, ISA 50V2, ISA 61VG, ISA 70 M VG, ISA 71 VG, ISA 201 VG and Gel 01 PR) formulated with heat-killed MAP were tested to determine the incidence of injection site lesions and the types of immune profiles generated in sheep. All the novel formulations produced fewer injection site lesions than a commercial vaccine (Gudair®). The immune profiles of the sheep differed between treatment groups, with the strength of the antibody and cell mediated immune responses being dependant on the adjuvant used. One of the novel vaccines resulted in a reduced IFN-γ immune response when a second "booster" dose was administered. These findings have significance for JD vaccine development because it may be possible to uncouple protective immunity from excessive tissue reactivity, and apparently poorly immunogenic antigens may be re-examined to determine if an appropriate immune profile can be established using different adjuvants. It may also be possible to formulate vaccines that produce targeted immunological profiles suited to protection against other pathogens, i.e. those for which a bias towards cellular or humoral immunity would be advantageous based on understanding of pathogenesis.

Prevalence of Coxiella burnetii in cattle and buffalo populations in Punjab, India.

Q fever is an important zoonosis of animal and public health significance but there is very limited information about its prevalence in the Punjab state of India. The current study was designed to estimate Q fever prevalence in cattle and buffalo populations of the state. We randomly selected 22 villages, one from each of the 22 districts of Punjab. Households in these villages were randomly selected using village voter lists to ensure representative sample collection. Blood, vaginal swab and milk samples were collected from the animals in these enrolled households. Serum samples were screened using Coxiella burnetii specific IgG ELISA whereas milk and genital swab samples were subjected to a Trans-PCR assay. The agreement (Cohan's Kappa) between shedding of C. burnetii in milk and genital secretions and between ELISA and Trans-PCR was estimated. The selected PCR products were sequenced, and phylogenetic analyses were performed. We collected 610 blood samples, 610 genital swabs and 361 milk samples from 610 bovines (378 cattle and 232 buffaloes) in 179 households. Considering all tests in parallel and after adjusting for clustering, we estimated an overall individual animal prevalence of Q fever of 7.0% (95% CI: 4.7, 9.4). There was a low agreement between shedding of C. burnetii in milk and genital secretion (kappa: 14.3%; 95% CI: 5.6, 22.9) and between ELISA and Trans-PCR (10.3%; 95% CI: 3.2, 17.4%). Phylogenetic analysis confirmed all samples to be of C. burnetii. The results suggest that the disease is present in the state and further epidemiological information should be collected to determine its zoonotic potential and its impact on animal and public health in Punjab, India.

Bayesian evaluation of three serological tests for the diagnosis of bovine brucellosis in Bangladesh.

We evaluated the performance of three serological tests - an immunoglobulin G indirect enzyme linked immunosorbent assay (iELISA), a Rose Bengal test and a slow agglutination test (SAT) - for the diagnosis of bovine brucellosis in Bangladesh. Cattle sera (n = 1360) sourced from Mymensingh district (MD) and a Government owned dairy farm (GF) were tested in parallel. We used a Bayesian latent class model that adjusted for the conditional dependence among the three tests and assumed constant diagnostic accuracy of the three tests in both populations. The sensitivity and specificity of the three tests varied from 84.6% to 93.7%, respectively. The true prevalences of bovine brucellosis in MD and the GF were 0.6% and 20.4%, respectively. Parallel interpretation of iELISA and SAT yielded the highest negative predictive values: 99.9% in MD and 99.6% in the GF; whereas serial interpretation of both iELISA and SAT produced the highest positive predictive value (PPV): 99.9% in the GF and also high PPV (98.9%) in MD. We recommend the use of both iELISA and SAT together and serial interpretation for culling and parallel interpretation for import decisions. Removal of brucellosis positive cattle will contribute to the control of brucellosis as a public health risk in Bangladesh.

Analysis of pig trading networks and practices in Uganda.

East Africa is undergoing rapid expansion of pig rearing, driven by increasing pork consumption. Introduction and expansion of pig production systems in this biodiverse landscape may create new risks, including zoonotic pathogen transmission. Historically, biosecurity measures have primarily been focused at farm level, ignoring the important function pig traders fulfill between farmers and consumers. This study interviewed pig traders operating at Uganda's only registered pork abattoir to describe their characteristics, business practices, biosecurity practices, and pig health management and reporting practices. All the traders were male, and nearly all (90.5%) relied on pig trading as their primary source of income. Most of the pigs brought for processing at the slaughterhouse were purchased from smallholder farms (87.3%). In addition, there was a significant difference in the high price paid per kilogram at farm gate by region (P = 0.005). High prices paid at farm gate were associated with holiday periods (P < 0.001), harvest season (P < 0.001), and drought (P < 0.001). Traders preferred buying live pigs from male farmers (88.9%) because they were considered the final decision makers and owned the pigs being sold. All pig traders were aware of clinical signs indicating a pig was sick. This study has provided baseline information on pig trader practices in Uganda. Improvements in local pork slaughterhouses and markets will benefit not only pig traders in accessing consistent customers but also individual pig farmers by increasing their market access. Finally, given their role as a link between farmers and consumers, traders would benefit from targeted inclusion in disease control and prevention strategies.

Associations of body condition score with health conditions related to overweight and obesity in cats.

OBJECTIVES: To explore the associations of cat body condition score with various health conditions, such as diabetes mellitus, dermatological conditions and hypertension, that have been shown to relate to overweight and/or obesity in cats, dogs or humans. MATERIALS AND METHODS: Electronic patient records between January 3, 2005 and June 21, 2015 were obtained from a cat-focused primary accession clinic in metropolitan Sydney where the body condition score of cats was routinely evaluated. Binomial logistic regression modelling was conducted to investigate the associations, after adjusting for age, sex and breed, between 21 health conditions and body condition score recorded on a 9-point scale. RESULTS: Fourteen of the 21 health conditions examined showed significant associations with an increased body condition score, particularly those of 7 and above. These were dermatological conditions, atopic dermatitis, musculoskeletal conditions, arthritis, hypertension, respiratory conditions, asthma, oral conditions, diarrhoea, general and lower urinary tract conditions, ophthalmic conditions, diabetes mellitus and allergic conditions. Additionally, cats with body condition score of 8 or 9 had significantly higher odds for gastrointestinal conditions and upper urinary tract conditions when compared with cats with body condition score of 5. CLINICAL SIGNIFICANCE: As far as we know, this is the first study reporting positive associations of high body condition score with atopic dermatitis, hypertension, asthma, diarrhoea, ophthalmic conditions and allergic conditions in cats. A large number of positive associations between health conditions and high body condition score indicates that excess fat mass should be given a greater emphasis in preventive health care for cats.

Estimation of the health and economic burden of human brucellosis in India.

High seroprevalence estimates of brucellosis in livestock species and humans in India suggest that the disease is a significant public health concern in the country. We developed an economic model and conducted an assessment of the impact of human brucellosis in India to describe the current situation to help formulate prevention and control strategies. Economic losses of human brucellosis were calculated based on the official records and the data from epidemiological surveys conducted in India. These data were used to estimate the disability adjusted life years (DALYs) due to human brucellosis. Uncertainty was incorporated in the model by applying probability distributions for certain input parameters. The analyses were further supplemented by conducting sensitivity analyses to determine which parameters had the biggest influence on the outcome of economic losses. The annual median losses due to human brucellosis were estimated to be Rs 627.5 million (uncertainty interval [95% UI] Rs 534.8-741.2 million; US $ 10.46 million) with a loss of Rs 442.3 million (95% UI 371.0-516.0; US $ 7.37 million) among adults and Rs 185.0 million (95% UI 124.0-255.0; US $ 3.08 million) among children. Human brucellosis in India caused a loss of 177 601 (95% UI 152 695-214 764) DALYs at the rate of 0.15 (95% UI 0.13-0.17) DALYs per thousand persons per year. The DALYs were found to be 0.29 (95% UI 0.08-0.70) per thousand persons per year in occupational and 0.13 (95% UI 0.06-0.18) in non-occupational adult population. This is the first systematic analysis of the health impact of human brucellosis in India and of indirect/production losses occurring due to human brucellosis anywhere in the world. The results indicate that brucellosis causes considerable economic losses and has a reasonable health impact, particularly among occupational groups. Intervention policies need to be strengthened to reduce the socio-economic impact of human brucellosis in India.

Investigation of the effect of Equivac® HeV Hendra virus vaccination on Thoroughbred racing performance.

OBJECTIVE: To evaluate the effect of Equivac® HeV Hendra virus vaccine on Thoroughbred racing performance. DESIGN: Retrospective pre-post intervention study. METHODS: Thoroughbreds with at least one start at one of six major south-eastern Queensland race tracks between 1 July 2012 and 31 December 2016 and with starts in the 3-month periods before and after Hendra virus vaccinations were identified. Piecewise linear mixed models compared the trends in 'Timeform rating' and 'margin to winner' before and after initial Hendra virus vaccination. Generalised linear mixed models similarly compared the odds of 'winning', 'placing' (1st-3rd) and 'winning any prize money'. Timeform rating trends were also compared before and after the second and subsequent vaccinations. RESULTS: Analysis of data from 4208 race starts by 755 horses revealed no significant difference in performance in the 3 months before versus 3 months after initial Hendra vaccination for Timeform rating (P = 0.32), 'Margin to winner' (P = 0.45), prize money won (P = 0.25), wins (P = 0.64) or placings (P = 0.77). Further analysis for Timeform rating for 7844 race starts by 928 horses failed to identify any significant change in Timeform rating trends before versus after the second and subsequent vaccinations (P = 0.16) or any evidence of a cumulative effect for the number of vaccines received (P = 0.22). CONCLUSION: No evidence of an effect of Hendra virus vaccination on racing performance was found. The findings allow owners, trainers, industry regulators and animal health authorities to make informed decisions about vaccination.

Risk factors for occupational Brucella infection in veterinary personnel in India.

Brucellosis is an important animal and human health issue in developing countries. This study aimed to identify risk factors associated with occupational Brucella infection in veterinary personnel in India. Blood samples were collected from 279 veterinary personnel working in the public sector. Sera were tested with rose bengal plate test (RBPT), standard tube agglutination test (STAT), and IgG and IgM ELISAs. Information about participant demographics, risk of exposure and infection control practices was collected using a self-completed questionnaire. The outcome measure of Brucella infection was created based on a positive RBPT or STAT test and a positive IgG ELISA test. Binomial logistic regression analyses were conducted to evaluate associations between explanatory variables and the outcome variable. Of the 279 participants, 61 (21.9%), 67 (24.0%), 55 (19.7%) and 150 (53.8%) were positive in RBPT, STAT, IgM and IgG ELISA, respectively. Compared to a trained veterinarian, veterinary pharmacists and animal handlers had greater odds of being test positive, suggesting that they were at greater risk of Brucella infection. Number of years spent working with animals was associated with greater odds of a person being positive for Brucella infection (p = .015). Counter-intuitively, those using personal protective equipment (PPE) for handling sick animals were found to be at greater risk, suggesting that either the use of PPE is inappropriate-making it ineffective-or that it is reverse association whereby those experiencing brucellosis symptoms start using PPE. Brucellosis is a common occupational zoonosis among veterinary personnel in India with the risk being higher in paraveterinary staff than veterinarians and in those who have been practicing for a longer period of time. Further investigations are required to clarify the effectiveness of PPE to reduce Brucella infection in veterinary personnel in India.

Exploring animal rabies endemicity to inform control programmes in Punjab, India.

Previous studies estimate that one-third of the annual global burden of rabies (~20,000 cases) occurs in India. Elimination of canine rabies is essential to reduce this burden. Surveillance of animal cases can assess both the risk to humans and the efficacy of control strategies. The objective of this study was to describe the spatial and temporal occurrence of reported confirmed cases of rabies in animals in Punjab, India, from 2004 to 2014. We analysed passive surveillance data on 556 samples submitted from 2004 to 2014 to GADVASU, Ludhiana, Punjab, India. Regression and time series analyses were conducted to understand seasonal and long-term variation of cases and identify cross-correlation of monthly cases between species. Spatio-temporal analyses assessed spatial autocorrelation of date of reporting, mean geographic centres of disease occurrence and clustering of cases using Kulldorff's space-time permutation statistic. The annual number of submissions and proportion of confirmed cases were consistent throughout 2004-2014. Most submissions (320; 57.6%) were confirmed rabies cases, including dogs (40.6%), buffalo (29.7%) and cattle (23.1%). Regression analysis of monthly cases in dogs showed seasonal variation with significant increases in cases in March and August. Monthly case numbers in buffalo decreased over time. Long-term temporal trend was not detected in dog and cattle cases. Time-series models identified significant cross-correlation between dog and buffalo cases, suggesting that buffalo cases were spillover events from dogs. Significant spatio-temporal variation or clusters of cases were not detected. These results indicate that rabies cases in animals-and therefore, the potential for exposure to humans-were temporally and spatially stable during 2004-2014 in Punjab, India. The endemic nature of rabies transmission in this region demands a coordinated, sustained control programme. This study provides baseline information for assessing the efficacy of rabies control measures and developing seasonally targeted dog vaccination and rabies awareness strategies.

Case definition terminology for paratuberculosis (Johne's disease).

Paratuberculosis (Johne's disease) is an economically significant condition caused by Mycobacterium avium subsp. paratuberculosis. However, difficulties in diagnosis and classification of individual animals with the condition have hampered research and impeded efforts to halt its progressive spread in the global livestock industry. Descriptive terms applied to individual animals and herds such as exposed, infected, diseased, clinical, sub-clinical, infectious and resistant need to be defined so that they can be incorporated consistently into well-understood and reproducible case definitions. These allow for consistent classification of individuals in a population for the purposes of analysis based on accurate counts. The outputs might include the incidence of cases, frequency distributions of the number of cases by age class or more sophisticated analyses involving statistical comparisons of immune responses in vaccine development studies, or gene frequencies or expression data from cases and controls in genomic investigations. It is necessary to have agreed definitions in order to be able to make valid comparisons and meta-analyses of experiments conducted over time by a given researcher, in different laboratories, by different researchers, and in different countries. In this paper, terms are applied systematically in an hierarchical flow chart to enable classification of individual animals. We propose descriptive terms for different stages in the pathogenesis of paratuberculosis to enable their use in different types of studies and to enable an independent assessment of the extent to which accepted definitions for stages of disease have been applied consistently in any given study. This will assist in the general interpretation of data between studies, and will facilitate future meta-analyses.

Variation in susceptibility of different breeds of sheep to Mycobacterium avium subspecies paratuberculosis following experimental inoculation.

Exposure to Mycobacterium avium subspecies paratuberculosis (MAP) does not always lead to Johne's disease. Understanding differences in disease susceptibility of individual animals is a key aspect to controlling mycobacterial diseases. This study was designed to examine the susceptibility or resistance of various breeds of sheep to MAP infection. Merino, Suffolk first cross Merino, Border Leicester, and Poll Dorset sheep were orally inoculated with MAP and monitored for 14 months. Clinical disease occurred more frequently in the Merino (42%) and Suffolk first cross Merino (36%) compared to the Border Leicester (12%) and Poll Dorset (11%) breeds. Infection risk, as determined by culture of gut and associated lymphoid tissues, ranged from 75% for the Suffolk first cross Merino to 47% for the Poll Dorset sheep. Significant differences were identified in the site in the intestines of the most severe histopathological lesions and the immune responses to infection between the breeds. However, there was no difference in faecal MAP shedding by clinical cases between breeds. All breeds tested were susceptible to MAP infection, as determined by infection and clinical disease development, although there were differences in the proportions of diseased animals between the breeds. Poll Dorset and Border Leicester sheep were more resilient to MAP infection but there was evidence that more animals could have developed disease if given more time. These findings provide evidence of potential differential disease susceptibility between breeds, further our understanding of disease pathogenesis and risks of disease spread, and may have an influence on control programs for paratuberculosis.

Retrospective study on the occurrence of canine lymphoma and associated breed risks in a population of dogs in NSW (2001-2009).

OBJECTIVE: To identify risk factors for canine lymphoma in dogs from New South Wales, Australia, and to compare factors affecting remission duration. METHODS: Client-owned dogs diagnosed with lymphoma presented to the University Veterinary Teaching Hospital (UVTH), University of Sydney, between 2001 and 2009 (n = 134) were compared with a control population of dogs seen in that period of time with a diagnosis other than lymphoma to evaluate association of explanatory variables (breed, age and sex) with the outcome (case or control status). RESULTS: The Australian Cattle Dog (odds ratio (OR) = 4.71; 95% confidence interval (Cl) 2.31-9.62; P < 0.001), Doberman (OR = 7.64; 95% Cl 2.87-20.34; P = 0.001) and Rottweiler (OR = 4.52; 95% Cl 2.09-9.73; P = 0.001) had increased odds of lymphoma among dogs attending the UVTH compared with crossbreds. The results suggested that the Border Collie (OR = 3.38; 95% Cl 1.52-7.53; P = 0.008) and Boxer (OR = 3.85; 95% Cl 1.65-8.95; P = 0.006) also have increased odds of lymphoma among the pure-breed dogs attending the UVTH when compared with crossbred dogs. CONCLUSIONS: The results of this study confirmed a breed predilection for lymphoma in dogs, with the Australian Cattle Dog and Doberman having increased odds of lymphoma.

What influences the home range size of free-roaming domestic dogs?

In many regions of the world domestic dogs are free roaming and live in close relationship with humans. These free-roaming domestic dogs (FRDD) can cause public health problems such as dog bites and transmission of infectious diseases. To effectively control diseases transmitted by FRDD, knowledge on the dogs' behaviour is required. To identify predictors of home range (HR) size, we collected global positioning system data from 135 FRDD living in eight Aboriginal and Torres Strait Islander communities in Northern Australia. The core HR size ranged from 0·17 to 2·33 ha and the extended HR size from 0·86 to 40·46 ha. Using a linear mixed effect model with a Restricted Maximum Likelihood approach, the dog's sex and reproductive status were identified as predictors of roaming. Non-castrated males had the largest HRs, followed by neutered females. Also, FRDDs were found to roam further during the pre- than the post-wet season. These findings have implications for infectious disease spread. Identification of risk groups for disease spread within a population allows for more targeted disease response and surveillance. Further investigation of predictors of roaming in other FRDD populations worldwide would increase the external validity of such studies.

Estimation of the health and economic burden of neurocysticercosis in India.

Taenia solium is an endemic parasite in India which occurs in two forms in humans: cysticercosis (infection of soft tissues) and taeniosis (intestinal infection). Neurocysticercosis (NCC) is the most severe form of cysticercosis in which cysts develop in the central nervous system. This study was conducted to estimate health and economic impact due to human NCC-associated active epilepsy in India. Input data were sourced from published research literature, census data and other official records. Economic losses due to NCC-associated active epilepsy were estimated based on cost of treatment, hospitalisation and severe injury as well as loss of income. The disability-adjusted life years (DALYs) due to NCC were estimated by combining years of life lost due to early death and the number of years compromised due to disability taking the disease incidence into account. DALYs were estimated for five age groups, two genders and four regions, and then combined. To account for uncertainty, probability distributions were used for disease incidence data and other input parameters. In addition, sensitivity analyses were conducted to determine the impact of certain input parameters on health and economic estimates. It was estimated that in 2011, human NCC-associated active epilepsy caused an annual median loss of Rupees 12.03 billion (uncertainty interval [95% UI] Rs. 9.16-15.57 billion; US $ 185.14 million) with losses of Rs. 9.78 billion (95% UI Rs. 7.24-13.0 billion; US $ 150.56 million) from the North and Rs. 2.22 billion (95% UI Rs. 1.58-3.06 billion; US $ 34.14 million) from the South. The disease resulted in a total of 2.10 million (95% UI 0.99-4.10 million) DALYs per annum without age weighting and time discounting with 1.81 million (95% UI 0.84-3.57 million) DALYs from the North and 0.28 million (95% UI 0.13-0.55 million) from the South. The health burden per thousand persons per year was 1.73 DALYs (95% UI 0.82-3.39). The results indicate that human NCC causes significant health and economic impact in India. Programs for controlling the disease should be initiated to reduce the socio-economic impact of the disease in India.

Evaluation of Serum Aspergillus-Specific Immunoglobulin A by Indirect ELISA for Diagnosis of Feline Upper Respiratory Tract Aspergillosis.

BACKGROUND: Serological tests for diagnosis of aspergillosis in immunocompetent humans and animals are based on Aspergillus-specific IgG (As-IgG). In humans with chronic pulmonary aspergillosis, As-IgA may be detectable even if IgG titers are negative. Cats with upper respiratory tract aspergillosis (URTA) have detectable As-IgG, but their ability to mount an IgA response and its diagnostic utility are unknown. OBJECTIVES: To determine whether serum As-IgA can be detected in cats with URTA and evaluate its diagnostic utility alone or combined with As-IgG. ANIMALS: Twenty-three cats with URTA (Group 1), 32 cats with other respiratory diseases (Group 2), and 84 nonrespiratory controls (Group 3). METHODS: Serum As-IgA and As-IgG was measured by indirect ELISA. Optimal cutoff values were determined by receiver-operating curve analysis. Sensitivity (Se) and specificity (Sp) for URTA diagnosis were determined. RESULTS: Serum IgA was detected in 91.3% of Group 1 cats. The Se of IgA detection was 78.3% and Sp was 96.9% for Group 2, 85.7% for Group 3 and 88.8% for Group 2 and 3 combined. Assay Se for IgG was 100% and Sp was 92.2%. Using combined IgA and IgG results at cutoffs optimized for Sp for IgA and Se for IgG and combined controls (Groups 2 and 3), Se for diagnosis was 100% and Sp was 91.4%. CONCLUSION AND CLINICAL IMPORTANCE: Most cats with URTA have serum As-IgA antibodies that can be detected by ELISA. Paired measurement of serum As-IgA and IgG shows no benefit for diagnosis of feline URTA over IgG alone.