Tropical Animal Health and Production, Oct 24, 2015
Serological surveys based on a planned sampling on bovine viral diarrhea virus (BVDV) infection i... more Serological surveys based on a planned sampling on bovine viral diarrhea virus (BVDV) infection in Brazilian cattle herds are scarce. A cross-sectional study was carried out to determine herd- and animal-level seroprevalences and to identify risk factors associated with herd-level seroprevalence for BVDV infection in the State of Paraíba, Northeastern Brazil, from September 2012 to January 2013. The state was divided into three sampling strata, and for each stratum, the prevalence of herds infected with BVDV and the prevalence of seropositive animals was estimated by a two-stage sampling survey. In total, 2443 animals were sampled from 478 herds. A virus-neutralization test was used for BVDV antibody detection. A herd was considered positive when at least one seropositive animal was detected. The herd- and animal-level prevalences in the State of Paraíba were 65.5 % (95 % confidence interval (CI) = 61.1-69.7 %) and 39.1 % (95 % CI = 33.1-45.6 %), respectively. The frequency of seropositive animals per herd ranged from 10 to 100 % (median of 50 %). The risk factors identified were as follows: more than six calves aged ≤12 months (odds ratio (OR) = 3.72; 95 % CI = 2.08-6.66), animal purchasing (OR = 1.66; 95 % CI = 1.08-2.55), pasture rental (OR = 2.15; 95 % CI = 1.35-3.55), and presence of veterinary assistance (OR = 2.04; 95 % CI = 1.10-3.79). Our findings suggest that the implementation of control and prevention measures among farmers, with the aim of preventing dissemination of the agent in the herds, is necessary. Special attention should be given to addressing the identified risk factors, such as sanitary control prior to animal purchasing and to discourage the pasture rental, as well as to encourage the vaccination in the herds.
Leptospirosis is a zoonotic disease that causes financial and significant problems for herds. The... more Leptospirosis is a zoonotic disease that causes financial and significant problems for herds. The objective was to define a prevalence of Leptospira spp. in serovar samples from 145 stray donkeys from the Brazilian semiarid region using the microscopic agglutination test (MAT), 24 serovars of Leptospira spp. Of the reactive animals, 34 of 145 (23%) had titers between 100 and 3,200. The serovars identified in the sera with high frequency were Kennewicki and Bratislava. In these animals serovars, Pyrogenes, Tarassovi, Canicola, Guaricura, Icterohaemorrhagiae, Grippotyphosa and Copenhageni were also used, showing animals with a lower rate of positive reactivity. This result indicates that the animals studied may be in contact with serovars Kennewicki and Bratislava, since wild animals, rodents and swine may harbor these serovars. Thus, the lack of adoption of protected sanitary measures may favor the occurrence of infection in the sampled animals, prevailing in the herd studied.
ABSTRACT: The aim of this survey was to identify spatial clustering of bovine paratuberculosis po... more ABSTRACT: The aim of this survey was to identify spatial clustering of bovine paratuberculosis positive herds in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling groups: sampling stratum 1 (mesoregion of Sertão), sampling stratum 2 (mesoregion of Borborema), and sampling stratum 3 (mesoregions of Zona da Mata and Agreste). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2504 cows aged ≥ 24 months were sampled from 480 herds. Indirect enzyme-linked immunosorbant assay (ELISA) test kits were used for Mycobacterium avium subsp. paratuberculosis (MAP) antibody detection. A herd was deemed positive for paratuberculosis if it included at least one positive animal in herds of up to 24 females, and two positive animals in herds with more than 24 females. Spatial cluste...
A cross-sectional study was carried out to estimate the animal- and herd-level prevalence of bovi... more A cross-sectional study was carried out to estimate the animal- and herd-level prevalence of bovine herpesvirus 1 (BoHV-1) infection in cattle in the State of Paraíba, and to identify risk factors associated with herd-level infection. The state was divided into three sampling strata, and for each stratum, the prevalence of herds infected with BoHV-1 was estimated through a two-stage sampling survey carried out from September 2012 to January 2013. In total, 2443 animals were sampled from 478 herds. A virus-neutralization test was used for BoHV-1 antibody detection. A Bayesian latent-class model was used to describe the data, taking into account imperfect diagnostic test characteristics and the non-independence of test results from animals within the same herd, and using a dynamic within-model risk factor selection method based on indicator variable selection. The adjusted herd-level prevalence was estimated to be 84% (95% CI: 80-88%) for the State of Paraíba, and the animal-level prevalence was estimated to be 73% (95% CI: 66-84%). Only five of the available risk factors were used by the model, with the three most influential being disposal of aborted foetuses (3.78, 95% CI: 1.11-13.85), sharing resources with other farms (3.0, 95% CI: 1.1-8,6), and a herd size of > 23 animals (2.5, 95% CI: 1.1-6.0). Our findings suggest that the animal- and herd-level seroprevalence of BoHV-1 infection in the State of Paraíba is high. While some risk factors such as herd size and sharing resources were identified as risk factors for BoHV-1 infection, these risk factors are initially likely to be of only minor relevance in a control programme due to the extremely high prevalence of infected farms. However, the results are relevant to the risk of reintroduction of disease on farms that have previously eradicated the disease.
Bovine Viral Diarrhea Virus (BVDV) and Bovine Herpesvirus type 1 (BoHV-1) cause reproductive prob... more Bovine Viral Diarrhea Virus (BVDV) and Bovine Herpesvirus type 1 (BoHV-1) cause reproductive problems in cattle and restrictions on international trade in animals worldwide. Both infections were detected in cattle herds in the Paraíba state, Northeastern Brazil, however, the spatial distribution and geographic identification of positive herds for these viruses has never been examined. Therefore, the aim of this study was to describe the spatial pattern of apparent prevalence estimate and to identify spatial clustering of positive herds of BVDV and BoHV-1 infections in cattle herds from the state of Paraíba, Northeastern Brazil. The herd-level prevalence for BVDV and BoHV-1 infections in Paraíba were, respectively, 65.5% (95% CI: 61.1-69.7) and 87.8% (95% CI: 84.5-90.5). The average apparent within-herd prevalence of BVDV was 31.8% and of BoHV-1 was 62.4%. The predicted prevalence was highest (0.42-0.75) for BVDV in the west, north and eastern part of Sertão and in the central and ea...
The aim of this study was to detect DNA and antibodies anti-Leishmania spp., Neospora caninum and... more The aim of this study was to detect DNA and antibodies anti-Leishmania spp., Neospora caninum and Toxoplasma gondii in captive and free-range crab-eating fox (Cerdocyon thous) from northeastern Brazil. Twenty-five crab-eating foxes from different states of northeastern Brazil were sampled by this study. Blood samples were collected by cephalic or jugular vein punctures. The whole blood was submitted to PCR, and the sera samples to the serological analysis as follows: MAT for T. gondii, NAT for N. caninum, and ELISA for L. chagasi. The frequence of antibodies anti-T. gondii was 50% and 29.41% for free-range and captive wild canids, respectively. The frequence of antibodies anti-N. caninum observed by this study was 62.50% and 23.52% for free-range and captive wild canids, respectively. The frequence of antibodies anti-L. chagasi was 4.0% for captive wild canids. Co-infections cases were identified as follows: one captive wild canid seropositive for T. gondii and L. chagasi and two fr...
This study focused on estimating the herd-level and animal-level prevalences, and identifying ris... more This study focused on estimating the herd-level and animal-level prevalences, and identifying risk factors associated with bovine cysticercosis in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling strata: Sertao, Borborema and Zona da Mata/Agreste. For each sampling stratum, herd-level and animal-level prevalences were estimated by a two-stage sampling survey. First, a pre-established number of herds (primary sampling units) were randomly selected; second, within each herd a pre-established number of cows aged ≥24months were systematically selected (secondary sampling units). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2382 animals were sampled from 474 herds. Serological diagnosis was initially performed by the indirect ELISA, and positive sera were confirm...
Tropical Animal Health and Production, Oct 24, 2015
Serological surveys based on a planned sampling on bovine viral diarrhea virus (BVDV) infection i... more Serological surveys based on a planned sampling on bovine viral diarrhea virus (BVDV) infection in Brazilian cattle herds are scarce. A cross-sectional study was carried out to determine herd- and animal-level seroprevalences and to identify risk factors associated with herd-level seroprevalence for BVDV infection in the State of Paraíba, Northeastern Brazil, from September 2012 to January 2013. The state was divided into three sampling strata, and for each stratum, the prevalence of herds infected with BVDV and the prevalence of seropositive animals was estimated by a two-stage sampling survey. In total, 2443 animals were sampled from 478 herds. A virus-neutralization test was used for BVDV antibody detection. A herd was considered positive when at least one seropositive animal was detected. The herd- and animal-level prevalences in the State of Paraíba were 65.5 % (95 % confidence interval (CI) = 61.1-69.7 %) and 39.1 % (95 % CI = 33.1-45.6 %), respectively. The frequency of seropositive animals per herd ranged from 10 to 100 % (median of 50 %). The risk factors identified were as follows: more than six calves aged ≤12 months (odds ratio (OR) = 3.72; 95 % CI = 2.08-6.66), animal purchasing (OR = 1.66; 95 % CI = 1.08-2.55), pasture rental (OR = 2.15; 95 % CI = 1.35-3.55), and presence of veterinary assistance (OR = 2.04; 95 % CI = 1.10-3.79). Our findings suggest that the implementation of control and prevention measures among farmers, with the aim of preventing dissemination of the agent in the herds, is necessary. Special attention should be given to addressing the identified risk factors, such as sanitary control prior to animal purchasing and to discourage the pasture rental, as well as to encourage the vaccination in the herds.
Leptospirosis is a zoonotic disease that causes financial and significant problems for herds. The... more Leptospirosis is a zoonotic disease that causes financial and significant problems for herds. The objective was to define a prevalence of Leptospira spp. in serovar samples from 145 stray donkeys from the Brazilian semiarid region using the microscopic agglutination test (MAT), 24 serovars of Leptospira spp. Of the reactive animals, 34 of 145 (23%) had titers between 100 and 3,200. The serovars identified in the sera with high frequency were Kennewicki and Bratislava. In these animals serovars, Pyrogenes, Tarassovi, Canicola, Guaricura, Icterohaemorrhagiae, Grippotyphosa and Copenhageni were also used, showing animals with a lower rate of positive reactivity. This result indicates that the animals studied may be in contact with serovars Kennewicki and Bratislava, since wild animals, rodents and swine may harbor these serovars. Thus, the lack of adoption of protected sanitary measures may favor the occurrence of infection in the sampled animals, prevailing in the herd studied.
ABSTRACT: The aim of this survey was to identify spatial clustering of bovine paratuberculosis po... more ABSTRACT: The aim of this survey was to identify spatial clustering of bovine paratuberculosis positive herds in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling groups: sampling stratum 1 (mesoregion of Sertão), sampling stratum 2 (mesoregion of Borborema), and sampling stratum 3 (mesoregions of Zona da Mata and Agreste). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2504 cows aged ≥ 24 months were sampled from 480 herds. Indirect enzyme-linked immunosorbant assay (ELISA) test kits were used for Mycobacterium avium subsp. paratuberculosis (MAP) antibody detection. A herd was deemed positive for paratuberculosis if it included at least one positive animal in herds of up to 24 females, and two positive animals in herds with more than 24 females. Spatial cluste...
A cross-sectional study was carried out to estimate the animal- and herd-level prevalence of bovi... more A cross-sectional study was carried out to estimate the animal- and herd-level prevalence of bovine herpesvirus 1 (BoHV-1) infection in cattle in the State of Paraíba, and to identify risk factors associated with herd-level infection. The state was divided into three sampling strata, and for each stratum, the prevalence of herds infected with BoHV-1 was estimated through a two-stage sampling survey carried out from September 2012 to January 2013. In total, 2443 animals were sampled from 478 herds. A virus-neutralization test was used for BoHV-1 antibody detection. A Bayesian latent-class model was used to describe the data, taking into account imperfect diagnostic test characteristics and the non-independence of test results from animals within the same herd, and using a dynamic within-model risk factor selection method based on indicator variable selection. The adjusted herd-level prevalence was estimated to be 84% (95% CI: 80-88%) for the State of Paraíba, and the animal-level prevalence was estimated to be 73% (95% CI: 66-84%). Only five of the available risk factors were used by the model, with the three most influential being disposal of aborted foetuses (3.78, 95% CI: 1.11-13.85), sharing resources with other farms (3.0, 95% CI: 1.1-8,6), and a herd size of > 23 animals (2.5, 95% CI: 1.1-6.0). Our findings suggest that the animal- and herd-level seroprevalence of BoHV-1 infection in the State of Paraíba is high. While some risk factors such as herd size and sharing resources were identified as risk factors for BoHV-1 infection, these risk factors are initially likely to be of only minor relevance in a control programme due to the extremely high prevalence of infected farms. However, the results are relevant to the risk of reintroduction of disease on farms that have previously eradicated the disease.
Bovine Viral Diarrhea Virus (BVDV) and Bovine Herpesvirus type 1 (BoHV-1) cause reproductive prob... more Bovine Viral Diarrhea Virus (BVDV) and Bovine Herpesvirus type 1 (BoHV-1) cause reproductive problems in cattle and restrictions on international trade in animals worldwide. Both infections were detected in cattle herds in the Paraíba state, Northeastern Brazil, however, the spatial distribution and geographic identification of positive herds for these viruses has never been examined. Therefore, the aim of this study was to describe the spatial pattern of apparent prevalence estimate and to identify spatial clustering of positive herds of BVDV and BoHV-1 infections in cattle herds from the state of Paraíba, Northeastern Brazil. The herd-level prevalence for BVDV and BoHV-1 infections in Paraíba were, respectively, 65.5% (95% CI: 61.1-69.7) and 87.8% (95% CI: 84.5-90.5). The average apparent within-herd prevalence of BVDV was 31.8% and of BoHV-1 was 62.4%. The predicted prevalence was highest (0.42-0.75) for BVDV in the west, north and eastern part of Sertão and in the central and ea...
The aim of this study was to detect DNA and antibodies anti-Leishmania spp., Neospora caninum and... more The aim of this study was to detect DNA and antibodies anti-Leishmania spp., Neospora caninum and Toxoplasma gondii in captive and free-range crab-eating fox (Cerdocyon thous) from northeastern Brazil. Twenty-five crab-eating foxes from different states of northeastern Brazil were sampled by this study. Blood samples were collected by cephalic or jugular vein punctures. The whole blood was submitted to PCR, and the sera samples to the serological analysis as follows: MAT for T. gondii, NAT for N. caninum, and ELISA for L. chagasi. The frequence of antibodies anti-T. gondii was 50% and 29.41% for free-range and captive wild canids, respectively. The frequence of antibodies anti-N. caninum observed by this study was 62.50% and 23.52% for free-range and captive wild canids, respectively. The frequence of antibodies anti-L. chagasi was 4.0% for captive wild canids. Co-infections cases were identified as follows: one captive wild canid seropositive for T. gondii and L. chagasi and two fr...
This study focused on estimating the herd-level and animal-level prevalences, and identifying ris... more This study focused on estimating the herd-level and animal-level prevalences, and identifying risk factors associated with bovine cysticercosis in the State of Paraíba, Northeastern Brazil. The state was divided into three sampling strata: Sertao, Borborema and Zona da Mata/Agreste. For each sampling stratum, herd-level and animal-level prevalences were estimated by a two-stage sampling survey. First, a pre-established number of herds (primary sampling units) were randomly selected; second, within each herd a pre-established number of cows aged ≥24months were systematically selected (secondary sampling units). Ten animals were sampled in herds with up to 99 cows aged over 24 months; 15 animals were sampled in herds with 100 or more cows aged over 24 months; and all animals were sampled in those with up to 10 cows aged over 24 months. In total, 2382 animals were sampled from 474 herds. Serological diagnosis was initially performed by the indirect ELISA, and positive sera were confirm...
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