Serological Evidence of Brucella abortus Prevalence in Punjab Province,Pakistan – A Cross‐Sectional Study

Twenty‐one villages in Punjab Province, seven from each region (North, Central & South) were randomly selected to determine the prevalence of B. abortus infection by two age categories (Group A: 0–2 years; Group B: >2 years) in cattle and buffalo populations. In each village, eight blood samples were collected from each age group of cattle and buffaloes. Sera from a total of 672 blood samples (336 each from cattle and buffaloes) were analysed for the presence of antibodies to B. abortus using rose bengal plate agglutination test (RBPT). Further confirmation of the RBPT‐positive samples was carried out using competitive ELISA. Overall, 43 of 672 (6.4%) sera were found positive for the presence of antibodies to B. abortus using RBPT. In cattle, the prevalence of B. abortus antibody was 5.06%, and in buffaloes, it was 7.74%. From the RBPT‐positive sera, 30 (70%) sera were confirmed for B. abortus antibodies using competitive ELISA. Results indicated that the prevalence of infection increased with the age of animals i.e. 3.27% and 9.52% in groups A and B, respectively. In cattle, incidence of these antibodies was 3.57% and 6.54% while in buffaloes, it was 2.98% and 12.50% in groups A and B, respectively. The region‐wise prevalence of B. abortus infection in buffaloes was 3.13%, 4.46% and 4.02% and in cattle, it was 3.13%, 1.79% and 2.68% in Northern, Central and Southern regions, respectively. This study provided baseline data on the occurrence of brucellosis infection in cattle and buffaloes at village level. This is the first study in Punjab province on the prevalence of brucellosis at village level.     

Variables Associated with Infections of Cattle by Brucella abortus., Leptospira spp. and Neospora spp. in Amazon Region in Brazil

The frequency of Neospora spp., Leptospira spp. and Brucella abortus infections in adult cattle was determined in herds of the State of Pará, Brazil, which is an important region for cattle production located in the Amazon region. A total of 3466 adult female cattle from 176 herds were tested, leading to a frequency of seropositive animals of 14.7%, 3.7% and 65.5% and a herd positivity of 87.4%, 41.3% and 98.8% for infections caused by Neospora spp., B. abortus and Leptospira spp., respectively. The five most frequently diagnosed serologic responses to Leptospira spp. were those against serovars hardjo, wolfii, grippotyphosa, hebdomadis and shermani. The following associations were found: practice of artificial insemination, large farm size, large herd size, large number of dogs and high number of total abortions per year with the presence of antibodies against serovar hardjo; positive results to serovar grippotyphosa with the presence of dogs; inappropriate disposal of aborted foetuses with positivity to serovar hebdomadis. Serovar grippotyphosa was also associated with number of episodes of abortions. Neospora spp. positive herds were associated with episodes of abortion and B. abortus infection with the disposal of dead animals and aborted foetuses on pastures and with the use of artificial insemination. In conclusion, the high frequency of brucellosis, leptospirosis and neosporosis in the region may be a consequence of social, natural and raising conditions as: (i) climate conditions that favour the survival and spread of pathogens in the environment; (ii) farms located in regions bordering forest areas; (iii) farms in areas of difficult access to the veterinary service; (iv) extensive beef herds raised at pastures with different age and productive groups inter‐mingled; and (v) minimal concerns regarding hygiene practices and disease prevention measures.     

Bovine Brucellosis in Argentina and Bordering Countries: Update

Bovine brucellosis is a zoonotic disease spread worldwide. The infection in cattle is predominantly caused by Brucella abortus and is usually detected in pregnant females through abortions. The disease is endemic in Argentina; however, infection in humans is underestimated and often not reported. The prevalence of bovine brucellosis in countries bordering Argentina is quite variable: 0.04% in Uruguay, 10.20% in the north and 0.06% in the south of Brazil, 0.2% in Chile, 3.15% in Paraguay and 2.27% in Bolivia. In 1999, the Argentine National Control and Eradication Program was implemented. Its strategies include identification of vaccinated animals, compulsory vaccination with B. abortus S19 of 100% of 3‐ to 8‐month‐old females, negative serological tests before animal movements and categorization of farms in terms of their brucellosis status. The epidemiological surveillance in milk is performed through the milk ring test and the indirect ELISA. The result of a national brucellosis survey performed in 2004 indicates that 12.4% (95% CI: 10.89–14.0) of Argentine beef farms are seropositive to Brucella and that the apparent prevalence in cattle is 2.10% (95% CI: 1.90–2.40). The official serological diagnostic tests are as follows: buffered plate antigen test, as screening, serum agglutination test, 2‐mercaptoethanol and fluorescence polarization assay, competitive ELISA, as confirmatory tests, and complement fixation test, as definitive test. Santa Fe and a district in Córdoba have ‘Outstanding Plans’. Tierra del Fuego is a ‘Zone free from bovine brucellosis’. One question arising when studying the Argentine situation is why the disease remains endemic if good regulations exist to control and eradicate it. In future, some different aspects might be evaluated to understand it, and further studies should be performed to prioritize, select and refine control strategies.     

Control of Bovine Brucellosis from Persistently Infected Holdings Using RB51 Vaccination with Test‐and‐Slaughter: A Comparative Case Report from a High Incidence Area in Portugal

Bovine brucellosis due to Brucella abortus infection causes significant reproductive and production losses in cattle and is a major zoonosis. Eradication of this disease has proved difficult to achieve in Portugal where it still occurs in some regions despite an ongoing national eradication programme. In 2004, the Alentejo region, a major cattle producing area, reported one of the highest levels of bovine brucellosis in the country, especially in one divisional area. In that area, bovine brucellosis was particularly problematic in a holding of ten herds, the largest extensive cattle unit in the country, which remained infected despite an extensive test‐and‐slaughter programme and depopulation of five herds. A 5‐year programme of RB51 vaccination with biannual test‐and‐slaughter was thus implemented in 2004. The apparent animal seroprevalence decreased from 19% (646/3,400) to 3% (88/2930) on the third herd‐level test and remained below 0.8% (27/3324) after the fourth test. After the tenth test, the holding had a prevalence of 0.1% (2/2332) and only one herd remained positive with a within‐herd prevalence of 1.1% (2/177). The results were compared to all other herds (n = 10) in the divisional area that were also persistently infected but were subject only to test‐and‐slaughter before being depopulated. In these herds, the strategy of test‐and‐slaughter did not reduce the prevalence, which remained significantly higher than the vaccinated group (median = 0.48% and 8.5% in vaccinated versus non‐vaccinated herds; Wilcoxon rank sum test; P < 0.01). The success of this pilot programme in continental Portugal provided a valuable case study to the official veterinary services by illustrating the value of RB51 vaccination with parallel testing and improved biosecurity as a comprehensive and sustainable strategy for bovine brucellosis control in persistently infected herds.     

Distribution of Schmallenberg Virus and Seroprevalence in Belgian Sheep and Goats

A serological survey to detect Schmallenberg virus (SBV)‐specific antibodies by ELISA was organized in the Belgian sheep population to study the seroprevalence at the end of the epidemic. One thousand eighty‐two sheep samples which were collected from 83 herds all over Belgium between November 2011 and April 2012 were tested. The overall within‐herd seroprevalence and the intraclass correlation coefficient were estimated at 84.31% (95% CI: 84.19–84.43) and 0.34, respectively. The overall between‐herd seroprevalence was 98.03% (95% CI: 97.86–98.18). A spatial cluster analysis identified a cluster of six farms with significantly lower within‐herd seroprevalence in the south of Belgium compared with the rest of the population (P = 0.04). It was shown that seroprevalence was associated to flock density and that the latter explained the presence of the spatial cluster. Additionally, 142 goat samples from eight different herds were tested for SBV‐specific antibodies. The within‐herd seroprevalence in goats was estimated at 40.68% (95% CI: 23.57–60.4%). The results of the current study provided evidence that almost every Belgian sheep herd has been in contact with SBV during 2011 and should be taken into consideration as part of comprehensive SBV surveillance and control strategies.     

Bovine Tuberculosis and Brucellosis in Cattle and African Buffalo in the Limpopo National Park,Mozambique

Bovine tuberculosis (BTB) and brucellosis are prevalent in buffaloes of the Kruger National Park (KNP, South Africa). Both diseases were considered to have no or a very low prevalence in wildlife and livestock in and around the Limpopo National Park (LNP, Mozambique). The same applies for tuberculosis in Gonarezhou National Park (GNP, Zimbabwe), but just recently, BTB was detected in buffaloes in the GNP and fears arose that the disease might also spread to the LNP as a result of the partial removal of the fences between the three parks to form the Great Limpopo Transfrontier Park. To assess the status of both diseases in and around LNP, 62 buffaloes were tested for bovine tuberculosis (BTB) and bovine brucellosis. The percentage of positive BTB reactors in buffalo was 8.06% using BovidTB Stat‐Pak^® and 0% with BOVIGAM^® IFN‐γ test and IDEXX ELISA. The brucellosis seroprevalence in buffalo was found to be 17.72% and 27.42% using Rose Bengal Test (RBT) and ELISA, respectively. In addition, 2445 cattle in and around the LNP were examined for BTB using the single intradermal cervical comparative tuberculin test (SICCT), and an apparent prevalence of 0.98% was found with no significant difference inside (0.5%) and outside (1.3%) the park. This is the first published report on the presence of positive reactors to BTB and bovine brucellosis in buffalo and cattle in and outside the LNP. Monitoring the wildlife–livestock–human interface of zoonotic high‐impact diseases such as BTB and brucellosis is of outmost importance for the successful implementation and management of any transfrontier park that aims to improve the livelihoods of the local communities.     

Seroprevalence of canine neosporosis and bovine viral diarrhoea in dairy cattle in selected regions of Kenya

Neospora caninum is the causative agent for canine neosporosis (CN), a disease of potential zoonotic importance causing reproductive losses in cattle while causing neuromuscular disease in dogs. Bovine viral diarrhoea on the other hand is caused by the bovine viral diarrhoea virus (BVDV) and is one of the most important reproductive diseases of cattle worldwide. In Kenya, these infections are of economic importance due to the losses they cause in farms in which they are diagnosed or are subclinical. Such losses include reduced milk production, reduced conception, early embryonic deaths and abortions which lead to reproductive wastage. This study was conducted between April 2017 and July 2018 and determined the seroprevalence of neoporosis and BVD in select dairy herds in Kenya. Kakamega, Nandi and Makueni Counties from where dairy farms were purposively sampled were used. Serum samples were collected from randomly selected dairy animals aged at least 2 years in the selected farms and screened for BVDV and CN antibodies. Seroprevalence of N. caninum was 24.1% (n = 552) and BVD, 52.3% (n = 545) across all the counties. Co‐infection where antibodies against the two infective agents were present was in 14.6% (n = 541) animals. Chi‐square tests of association between prevalence and county were significant for BVD (p = .000) but not for neosporosis (p = .626). Further chi‐square tests of association between the two infections were not significant (p = .105) neither were the associations of BVD (p = .575) and neosporosis (p = .626) on pregnancy status. These two diseases are rarely investigated as causes of bovine infertility. Detection of antibodies in the studied dairy herds underpins the need for enhanced surveillance by laboratories and for further studies to understand associated risk factors to formulate effective control strategies in dairy cattle to forestall abortions and production and reproduction losses.     

Seroprevalence of brucellosis in goats and sheep in Thailand: Results from the Thai National Brucellosis Surveillance System from 2013 to 2015

In Thailand, brucellosis re‐emerged in humans in 2003 and is considered a public health risk to goat farmers as the disease is endemic in small ruminants. The Thai Department of Livestock Development (DLD ) established a nationwide surveillance system for brucellosis in goats and sheep in 1997. Using data from this surveillance system, we describe the seroprevalence of brucellosis from 2013 to 2015 in small ruminants and the spatial distribution of the disease throughout Thailand. Surveillance data collected included the number of animals and herds tested, the province of the animal and herd and the laboratory results. Seroprevalence was estimated at both the animal and herd levels. During the 3‐year period, 443,561 goats and sheep were tested for brucellosis by the DLD throughout Thailand using the Rose Bengal Plate Test (RBPT ) and the enzyme‐linked immunosorbent assay test for Brucella . Among the 3 years, 2013 had the highest proportion of herds that tested positive for brucellosis at 13.80% (95% CI, 12.52, 15.16). Overall, this study found that brucellosis seroprevalence in small ruminants is decreasing throughout Thailand. However, there is variability in the spread of the disease with provinces in the eastern and western regions of Thailand having higher proportions of animals and herds testing positive. Overall provinces in the south had the lowest proportion of animals and herds testing positive for brucellosis. Periodic review of surveillance data documents the impact of the current brucellosis control programme and supports a targeted response in higher prevalence regions when there are limited financial resources for control measures.     

Prevalence of Chlamydophila psittaci Infections in the Eyes of Cattle,Buffaloes, Sheep and Goats in Contact with a Human Population

This work is an example of cooperation between veterinary and human medicine being fully complementary and at the same time, indispensable to improve our knowledge on animal chlamydiosis. This study investigated the existence of ocular chlamydiae and determined the prevalence of its presence, chlamydiosis, in asymptomatic and diseased farm animals and adjacent humans. Data were obtained by the omp2 gene family Chlamydiaceae‐specific PCR. Two hundred cattle, buffaloes, sheep and goats and 44 human specimens were also examined. Conjunctival swabs from both the eyes were collected from all animals and humans using cotton swabs. Samples were tested for chlamydiae by Vero cells tissue culture, chicken embryo, modified Gimenez staining, direct fluorescein‐conjugated monoclonal antibody staining (FA), immunoperoxidase, CFT and PCR. The PCR‐RFLP revealed that Chlamydophila psittaci demonstrated in the conjunctival samples of cattle (68% asymptomatic and 88% diseased), of buffalo (68% asymptomatic and 72% diseased), of sheep (68% asymptomatic and 80% diseased), of goat (76% asymptomatic and 92% diseased) and of humans (77% asymptomatic and 82% diseased). The Cp. psittaci was the only chlamydiae demonstrated in all of the ocular conjunctival samples, which confirms the prevalence of Cp. psittaci in this population of animals and adjacent humans. Statistically, the animal species factor was calculated and was found to be of no significance. Yet, there appeared to be a significant difference in the percentage of animal that tested positive using the different methods. Detection of Cp. psittaci in most samples confirms the prevalence of Cp. psittaci in this population of animals and adjacent humans.     

The Prevalence of Brucellosis in Cattle,Goats and Humans in Rural Uganda: A Comparative Study

A cross‐sectional study was conducted to determine the presence of brucellosis in cattle, goats and humans in farms from south‐western Uganda and identify risk factors associated with brucellosis in these three host groups. Data and serum samples were collected from 768 cattle, 315 goats and 236 humans, with 635 samples of bovine milk, from 70 farms in two different study areas in south‐western Uganda. Sera from livestock were tested with the Rose Bengal Plate test, using B. abortus and B. melitensis antigens, and human sera were tested with a commercial IgG/IgM lateral flow assay. Milk samples were tested using the OIE‐approved milk ring test. Screening tests for brucellosis were positive in 14% of cattle serum, 29% of bovine milk, 17% of goat serum and 11% of human serum samples. There were significant differences in the test prevalence of brucellosis by study site, with levels higher in the study area near Lake Mburo National Park than in the study area near Queen Elizabeth National Park. Multivariable regression models identified risk factors associated with increasing test positivity at the individual and farm levels for cattle, goats and humans. Positive associations were seen between increasing seropositivity of brucellosis in goats, cattle and humans. Results of multivariable analyses suggest that improvements in farm biosecurity and hygiene may reduce the risk of brucellosis on the farm and suggest a role for ticks in bovine brucellosis. Although cattle are the focus of brucellosis control in Uganda, the significant associations between seropositivity in humans and seropositivity in goats suggest that brucellosis in goats may be an important contributor to the epidemiology of the disease on the farm.     

Naturally acquired bovine besnoitiosis: Disease frequency,risk and outcome in an endemically infected beef herd

The recent spread of bovine besnoitiosis warrants further epidemiological investigations to improve the knowledge on disease development. Thus, a 4‐year longitudinal open cohort study was conducted in the first German cattle herd naturally infected with Besnoitia besnoiti . At seven herd‐visits between 2008 and 2012, fourteen breeding bulls (>1.5 years) and 131 females (>1 year) were examined clinically and serologically. In females, clinical and serological prevalences, incidence and remission rates were determined. In addition, the association of age, antibody levels and number of visible parasitic cysts with clinical and serological outcome was investigated. The seroprevalence (89.4%–100%) and serological incidence rate (140.5 per 100 animal‐years) were considerably higher than the clinical prevalence (23.5%–36.6%) and clinical incidence rate (16.7 per 100 animal‐years). Of 33 new clinical and 12 new serological cases, only 6.7% (3/45) attracted attention with clinical signs of acute bovine besnoitiosis. The apparent serological remission rate (1.9 per 100 animal‐years) was considerably lower than the clinical remission rate (37.3 per 100 animal‐years). A median cyst score of <1 and mean immunofluorescent antibody test (IFAT ) titre of ≤1,600 over the entire observation period was significantly associated with a negative clinical outcome at the end. Overall cyst score was not significantly associated with serological outcome and age had no significant influence on clinical and serological outcome. Within 4 years, there was a significant reduction in cyst scores and IFAT titres in the same animals, leading to eight clinically and serologically negative animals in the end. Two initially negative animals achieved clinical and apparent serological remission in about 2.5 years. In bulls, the time between herd entry and seroconversion was 7–30 months and the serological incidence rate was nearly identical to the rate in females (142.0 per 100 animal‐years). This shows that a high B. besnoiti prevalence leads to infection of bulls within a short time period.     

Molecular detection and genetic diversity of Bartonella species in large ruminants and associated ectoparasites from the Brazilian Cerrado

Currently, five Bartonella species and an expanding number of Candidatus Bartonella species have globally been reported in ruminants. Likewise, different Bartonella genotypes were identified. However, studies relating to ruminant‐associated Bartonella in Brazil are scarce. The current study aimed to assess the prevalence and genetic diversity of Bartonella in cattle, buffaloes and associated ectoparasites in Brazil. For this purpose, EDTA‐blood samples from 75 cattle and 101 buffaloes were sampled. Additionally, 128 Rhipicephalus microplus and one Amblyomma sculptum ticks collected from cattle, and 197 R. microplus, one A. sculptum and 170 lice (Haematopinus tuberculatus) collected from buffaloes were included. Bartonella DNA was initially screened through an HRM real‐time PCR assay targeting the 16S–23S internal transcribed spacer (ITS), and the positive samples were submitted to an additional HRM assay targeting the ssrA gene. The HRM‐positive amplicons were sequenced, and the nucleotide identity was assessed by BLASTn. Bartonella spp.‐positive DNA samples were analysed by conventional PCR assays targeting the gltA and rpoB genes, and then, the samples were cloned. Finally, the phylogenetic positioning and the genetic diversity of clones were assessed. Overall, 21 of 75 (28%) cattle blood samples and 13 of 126 (10.3%) associated ticks were positive for Bartonella bovis. Out of 101 buffaloes, 95 lice and 188 tick DNA samples, one (1%) buffalo and four (4.2%) lice were positive for Bartonella spp. Conversely, none of the ticks obtained from buffaloes were positive for Bartonella. The Bartonella sequences from buffaloes showed identity ranging from 100% (ITS and gltA) to 94% (ssrA) with B. bovis. In contrast, the Bartonella DNA sequences from lice were identical (100%) to uncultured Bartonella sp. detected in cattle tail louse (Haematopinus quadripertusus) from Israel in all amplified genes. The present study demonstrates the prevalence of new B. bovis genotypes and a cattle lice‐associated Bartonella species in large ruminants and their ectoparasites from Brazil. These findings shed light on the distribution and genetic diversity of ruminant‐ and ectoparasite‐related Bartonella in Brazil.     

Herd‐Level Risk Factors for the Seropositivity to Mycoplasma hyopneumoniae and the Occurrence of Enzootic Pneumonia Among Fattening Pigs in Areas of Endemic Infection and High Pig Density

The aim of the present study was to identify potential risk factors for the occurrence of enzootic pneumonia (EP) in herds situated in a region of high pig density, where a majority of herds is endemically infected with Mycoplasma hyopneumoniae. Between 2006 and 2010, overall 100 herds were enrolled in a case–control study. Data were collected through personal interview with the farmers, clinical examination of pigs and their environments, and serological testing for M. hyopneumoniae, swine influenza virus and porcine reproductive and respiratory syndrome virus. There were 40 case herds (coughing index high, seroprevalence high) with a mean coughing index of 4.3 and a seroprevalence of 86.6%. There were two control groups. Control group I consisted of 25 herds (coughing index low, seroprevalence low) with mean values of 0.7 and 11.2%, and 35 herds were allocated to control group II (coughing index low, seroprevalence high) where the mean coughing index was 0.9 and seroprevalence 86.3%. Case herds and control II herds had an increased age of piglets at weaning compared to control I herds. Any contact between fattening pigs of different age during restocking of compartments increased the risk for the occurrence of EP in a herd. Finally, farms that use living animals for the exposure to gilts during the acclimatization and farms that had increased number of weaned piglets per sow and year were less likely to test positive for M. hyopneumoniae and less likely to develop clinical symptoms of EP in fattening pigs.     

Large‐Scale Cross‐Sectional Serological Survey of Schmallenberg Virus in Belgian Cattle at the End of the First Vector Season

A cross‐sectional survey was conducted in the Belgian cattle population after the first period of infection of the emerging Schmallenberg virus. A total number of 11 635 cattle from 422 herds sampled between 2 January and 7 March 2012 were tested for the presence of Schmallenberg‐specific antibodies using an ELISA kit. Between‐herd seroprevalence in cattle was estimated at 99.76% (95% CI: 98.34–99.97) and within‐herd seroprevalence at 86.3% (95% CI: 84.75–87.71). An Intraclass Correlation Coefficient of 0.3 (P < 0.001) was found, indicating that the correlation between two animals within a herd with respect to their serological status was high. Those results corroborate the conclusion that the Schmallenberg virus was widespread in Belgium during winter 2011. Seroprevalence was shown to be statistically associated to the animal's age (P < 0.0001): with 64.9% (95% CI: 61.34–68.3) estimated for the 6–12 months of age, 86.79% (95% CI: 84.43–88.85) for the 12–24 months of age and 94.4% (95% CI: 93.14–95.44) for the animals older than 24 months. Based on the results of the described serological survey, we can conclude that after the first Schmallenberg virus episode, almost every Belgian cattle has already been in contact with the virus. In consequence, the vast majority of the host animals should have developed post infection protective immunity against the virus.     

Testicular thermoregulation,scrotal surface temperature patterns and semen quality of water buffalo bulls reared in a tropical climate

This study evaluated the capacity of thermoregulation and its consequences on the scrotal surface temperature patterns and semen quality of buffalo bulls raised in a wet tropical climate. Eleven water buffaloes were evaluated in the rainiest, in the transitional and in the less rainy season. Air temperature and humidity were consistently high, but the animals did not show thermal stress in any season. The scrotal temperature gradient of buffalo bulls using infrared thermography was described, and three parallel and decreasing thermal bands were characterised. Sperm quality (n = 176 ejaculates) was maintained in normal parameters over the periods. Pearson's coefficients showed that sperm volume and progressive motility were negatively correlated with ocular globe, epididymal tail and minimum scrotal temperatures (p < .01). Sperm membrane integrity was negatively influenced by increases in epididymal tail and minimum scrotal temperatures (p < .01). Ocular globe temperature also showed positive correlation with rectal, spermatic cord, and epididymal tail temperatures (p < .01). Therefore, even under high temperature and humidity, the thermoregulatory system was effective in preventing heat stress and the normality of scrotal surface temperatures, spermatogenesis and sperm maturation were maintained.     

Description of Events Where African Buffaloes (Syncerus caffer) Strayed from the Endemic Foot‐and‐Mouth Disease Zone in South Africa, 1998–2008

African buffaloes (Syncerus caffer) are reservoir hosts of Southern African Territories (SAT) foot‐and‐mouth disease (FMD) virus strains. In South Africa, infected buffaloes are found in the FMD‐infected zone comprising the Kruger National Park (KNP) and its adjoining reserves. When these buffaloes stray into livestock areas, they pose a risk of FMD transmission to livestock. We assessed 645 records of stray buffalo events (3124 animals) from the FMD infected zone during 1998–2008 for (i) their temporal distribution, (ii) group size, (iii) age and gender composition, (iv) distance from the infected zone fence and (v) outcome reported for each event. A maximum entropy model was developed to evaluate spatial predictors of stray buffalo events and assess current disease control zones. Out of all buffaloes recorded straying, 38.5% escaped from the FMD infected zone during 2000/2001, following floods that caused extensive damage to wildlife fences. Escape patterns were not apparently influenced by season. The median size of stray groups was a single animal (IQR [1–2]). Adult animals predominated, comprising 90.4% (620/686) of the animals for which age was recorded. Of the 315 events with accurate spatial information, 204 (64.8%) were recorded within 1 km from the FMD infected zone. During late winter/spring (June–October), stray buffaloes were found significantly closer to the FMD infected zone (median = 0.3 km, IQR [0.1–0.6]). Less than 13% (40/315) of stray groups reached the FMD protection zone without vaccination, posing a higher risk of spreading FMD to these more susceptible livestock. Model outputs suggest that distance from the FMD infected zone, urban areas and permanent water sources contributed almost 85% to the spatial probability of stray buffalo events. Areas with a high probability for stray buffalo events were well covered by current disease control zones, although FMD risk mitigation could be improved by expanding the vaccination zone in certain areas.     

Bovine Viral Diarrhoea Virus (BVDV) in Dairy Cattle: A Matched Case–Control Study

Bovine viral diarrhoea virus (BVDV) causes one of the most important diseases of cattle in terms of economic costs and welfare. The aims were to estimate herd prevalence and to investigate the factors associated with antibodies in bulk tank milk (BTM) in dairy herds through a matched case–control study. To estimate herd prevalence, BTM samples were randomly selected (n = 314) from a population (N = 1604). The true prevalence of BVDV was 24.3% (CI 95% = 20.1–29.3%). For the case–control study, BVDV antibody‐positive herds (high antibody titres) were classified as cases (n = 21) and matched (n = 63) by milk production with herds presenting low antibody titres (ratio of 1 : 3). Three multivariable models were built: 1) full model, holding all 21 variables, and two models divided according to empirical knowledge and similarity among variables; 2) animal factor model; and 3) biosecurity model. The full model (model 1) identified: age as a culling criteria (OR = 0.10; CI 95% = 0.02–0.39; P < 0.01); farms that provided milk to other industries previously (OR = 4.13; CI 95% = 1.17–14.49; P = 0.02); and isolation paddocks for ill animals (OR = 0.14; CI 95% = 0.01–0.26; P = 0.02). The biosecurity model revealed a significant association with the use of natural mating (OR = 9.03; CI 95% = 2.14–38.03; P < 0.01); isolation paddocks for ill animals (OR = 0.06; CI 95% = 0.05–0.83; P = 0.03); years providing milk for the same industry (OR = 0.94; CI 95% = 0.91–0.97; P = 0.02); and direct contact over fences among cattle of neighbouring farms (OR = 5.78; CI 95% = 1.41–23.67; P = 0.04). We recommend the application of grouping predictors as a good choice for model building because it could lead to a better understanding of disease–exposure associations.     

Factors associated with the prevalence of antibodies against Theileria equi in equids of Western Pará, Brazil

The State of Pará has one of the largest herds of equids (horse, donkey and mule) in Brazil, most of these animals are found on cattle farms. Equine theileriosis is a tick‐borne disease caused by the parasite Theileria equi and is characterized by fever, anaemia, icterus, intravascular haemolysis, haemoglobinuria, spleen and hepatomegaly, and even death. The present study aimed to determine the prevalence of antibodies against T. equi in equids in the western region of the State of Pará, Brazil, and to identify potential risk factors associated with parasite infection. A cross‐sectional study was conducted with cluster sampling of farm horses from 18 municipalities. In the cities visited, samples from sport and carthorses were also included. Serum was obtained to detect T. equi‐specific antibodies using an indirect enzyme‐linked immunosorbent assay (iELISA) based on a crude parasite antigen. In order to identify possible risk factors of the infection which are associated with the prevalence of antibodies, a chi‐squared test was carried out. Of 1,117 equids, 373 tested positive for T. equi antibodies with an overall prevalence of 33.4% (31.3%–37.0% for the 95% confidence interval). Sex, animal species and breed were found not to be associated with the presence of T. equi antibodies, whereas age, the presence of dogs or ticks were associated with seropositivity (p < 0.05). Horses with ticks were 2.4 more likely seropositive than horses without ticks. The presence of dogs in the equid habitat and the presence of ticks resulted in a higher T. equi seropositive rate probably because dogs are hosts for vector ticks of T. equi. Our study represents the first report of T. equi antibodies in equids of western Pará revealing a widespread distribution of seropositive animals.     

Isolation of Brucella abortus from a Dog and a Cat Confirms their Biological Role in Re‐emergence and Dissemination of Bovine Brucellosis on Dairy Farms

Brucellosis is highly contagious bacterial zoonoses affecting a wide range of domesticated and wild animals. In this study, Brucella (B.) abortus bv 1 was identified in uterine discharge of apparently healthy bitch and queen with open pyometra housed on a cattle farm. This study highlights the role of dogs and cats as symptomatic carriers and reservoirs for Brucella. To the best of our knowledge, this study represents the first report of feline infection with B. abortus bv 1 globally. These pet animals may contaminate the environment and infect both livestock and humans. Surveillance and control programmes of brucellosis have to include eradication of the disease in dogs, cats and companion animals.     

Serological Survey of Porcine circovirus‐2 in Captive Wild Boars (Sus scrofa) from Registered Farms of South and South‐east Regions of Brazil

This study aimed to survey captive wild boars for antibodies against Porcine circovirus‐2 (PCV‐2) in registered farms. Serum samples (n = 1305) were collected from 90‐day‐old wild boars from 118 farms of the Brazilian South‐east region, including the states of Minas Gerais and São Paulo, and South region, including the states of Paraná, Rio Grande do Sul and Santa Catarina. All herds (100%) presented reactive animals, in varying numbers and from low‐to‐high antibody titres, with the occurrence ranging from 82 to 89%. Considering farms, the average prevalence was of 84.9% (P < 0.05) and ranged from 54.1 to 94.95%. Regarding the geographic regions studied, the prevalence was of 100%, with PCV2 antibodies detected in wild boars of all regions. This study provides the first evidence of PCV2 antibodies in captive wild boars in Brazil.