RESUMO
Blue eye disease (BED) of pigs was identified in the early 1980s in La Piedad, Michoacan, Mexico. The causal agent is Porcine orthorubulavirus (PRV), which affects pigs of all ages, producing nervous, respiratory, and reproductive disorders. BED is geographically endemic to the center of Mexico, where 75% of the country's swine industry is concentrated. Due to its adverse effects on the swine industry and the risk of dissemination to other countries, it is essential to have reliable diagnostic methods for BED. The objective of this study was to establish the optimal conditions for three serological tests, hemagglutination inhibition (HI), immunoperoxidase monolayer assay (IPMA), and serum neutralization (SN), and to compare their sensitivity, specificity, kappa coefficient, and predictive values. Twelve different HI protocols (9408 tests), one SN protocol and one IPMA protocol (784 tests, each) were evaluated. Forty-nine sera were analyzed, and thirty-seven sera showed true positive results, while twelve showed true negative results. The kappa coefficient was used to assess the variation in each test. The best HI protocol registered a sensitivity and specificity of 89 and 100%, respectively, the IPMA test showed values of 85 and 100%, and the SN test registered a sensitivity of 91% and a specificity of 96%. One of the disadvantages of the HI test is that when chicken red blood cells (RBCs) are used, elution occurs in a short incubation time, which would decrease the specificity. The use of bovine RBCs increases the specificity of the testy and makes it more stable, but it decreases the sensitivity. The results of HI and SN revealed the importance of eliminating the complement system of the serum and removing other inhibitors to avoid test nonspecificity. The IPMA test does not use an active virus; hence, it is considered safe and does not present any risk of disseminating PRV.
Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Infecções Oculares Virais/diagnóstico , Testes de Inibição da Hemaglutinação/veterinária , Técnicas Imunoenzimáticas/veterinária , Infecções por Rubulavirus/diagnóstico , Rubulavirus/imunologia , Testes Sorológicos/veterinária , Doenças dos Suínos/diagnóstico , Animais , Biomarcadores/sangue , Infecções Oculares Virais/sangue , Infecções Oculares Virais/imunologia , Infecções Oculares Virais/virologia , Testes de Inibição da Hemaglutinação/normas , Técnicas Imunoenzimáticas/normas , México , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Infecções por Rubulavirus/sangue , Infecções por Rubulavirus/imunologia , Infecções por Rubulavirus/virologia , Testes Sorológicos/normas , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologiaRESUMO
Heat stress is major welfare concern during transport of pigs in tropical climates, which can also lead to direct production costs. This study evaluated the dynamics of heat zones through the load and their relationship with heat stress of weaner pigs during road transport in a tropical climate. Both environmental (e.g. temperature and relative humidity) and physiological (e.g. respiratory frequency and lactate) measures were recorded from four vehicle journeys (70 km distance, 216 weaner pigs within each trailer load) within Ceará, northeastern Brazil. Geostatistics and fluid dynamics simulation techniques were applied to understand the dynamics of heat zones and ventilation patterns the truckload. Statistics based on canonical discriminant analysis and ANOVA were performed to verify the relationship between heat zones and heat stress in pigs. The results showed that, during transport, the generation of heat zones occurred with different magnitudes along the load (P < 0.05), which was harmonized by the ventilation dynamics. There was a heat core with high energy content, in the front region of the lower deck (LD) of the trailer. In this zone, weaners pigs had higher rectal temperature (+1.8 °C temperature difference), respiratory frequency (LD = 94 ± 1.3 breaths/min; UD = 86 ± 1.3 breaths/min), and blood cortisol concentration (LD = 32.9 ± 0.8 ng/mL; UD = 30.18 ± 0.6 ng/mL) (all P < 0.05). Weaners pigs transported in the upper deck (UD) compartments had the highest skin temperature (LD = 38.13 ± 0.3 °C; UD = 38.9 ± 0.22 °C) and the highest mean values of blood lactate (LD = 65.5 ± 1.11 m/M; UD = 71.60 ± 1.19 m/M) and Creatine kinase (LD = 3891.23 ± 69U/L; UD = 4107.43 ± 62U/L) (P < 0.05). Weaners transported in compartments of the LD of trailer were more susceptible to heat stress, while weaners in the UD compartments were more susceptible to physical stress and muscle exhaustion. These results provide additional evidence of heat zones within trailer compartments and highlight the requirement for the planning of pig transport operations in tropical climates to mitigate risks of heat stress.
Assuntos
Resposta ao Choque Térmico/fisiologia , Microclima , Suínos/fisiologia , Meios de Transporte , Criação de Animais Domésticos , Animais , Temperatura Corporal , Brasil , Creatina Quinase/sangue , Feminino , Transtornos de Estresse por Calor/sangue , Transtornos de Estresse por Calor/fisiopatologia , Transtornos de Estresse por Calor/veterinária , Temperatura Alta , Hidrocortisona/sangue , Ácido Láctico/sangue , Respiração , Suínos/sangue , Doenças dos Suínos/sangue , Doenças dos Suínos/fisiopatologia , Clima TropicalRESUMO
BACKGROUND: Rickettsia bacteria are responsible for diseases in humans and animals around the world, however few details are available regarding its ecology and circulation among wild animals and human populations at high transmission risk in Brazil. The aim of this study was to investigate the occurrence of ticks and Rickettsia spp. in wild boars, corresponding hunting dogs and hunters. METHODS: Serum samples and ticks were collected from 80 free-range wild boars, 170 hunting dogs and 34 hunters from southern and central-western Brazil, from the Atlantic Forest and Cerrado biomes, respectively, between 2016 and 2018. Serum samples were tested by indirect immunofluorescent-antibody assay (IFA) to detect IgG antibodies against Rickettsia rickettsii, Rickettsia parkeri, Rickettsia bellii, Rickettsia rhipicephali and Rickettsia amblyommatis. Tick species were identified by morphological taxonomic keys, as previously described. A total of 164 ticks including A. sculptum, A. brasiliense and A. aureolatum were tested in PCR assays for Spotted Fever Group (SFG) Rickettsia spp. RESULTS: A total of 58/80 (72.5%) wild boars, 24/170 (14.1%) hunting dogs and 5/34 (14.7%) hunters were positive (titers ≥ 64) to at least one Rickettsia species. A total of 669/1,584 (42.2%) ticks from wild boars were identified as Amblyomma sculptum, 910/1,584 (57.4%) as Amblyomma brasiliense, 4/1,584(0.24%) larvae of Amblyomma spp. and 1/1,584 (0.06%) nymph as Amblyolmma dubitatum. All 9 ticks found on hunting dogs were identified as Amblyomma aureolatum and all 22 ticks on hunters as A. sculptum. No tested tick was positive by standard PCR to SFG Rickettsia spp. CONCLUSIONS: The present study was the concomitant report of wild boar, hunting dog and hunter exposure to SFG rickettsiae agents, performed in two different Brazilian biomes. Wild boar hunting may increase the risk of human exposure and consequently tick-borne disease Wild boars may be carrying and spreading capybara ticks from their original habitats to other ecosystems. Further studies can be required to explore the ability of wild boars to infecting ticks and be part of transmission cycle of Rickettsia spp.
Assuntos
Anticorpos Antibacterianos/sangue , Doenças do Cão/sangue , Cães/sangue , Infecções por Rickettsia/sangue , Infecções por Rickettsia/veterinária , Rickettsia/imunologia , Doenças dos Suínos/sangue , Carrapatos/imunologia , Animais , Animais Selvagens/sangue , Animais Selvagens/microbiologia , Brasil , Doenças do Cão/microbiologia , Cães/microbiologia , Feminino , Humanos , Masculino , Rickettsia/classificação , Rickettsia/isolamento & purificação , Infecções por Rickettsia/microbiologia , Sus scrofa/sangue , Sus scrofa/microbiologia , Suínos , Doenças dos Suínos/microbiologia , Carrapatos/classificação , Carrapatos/microbiologiaRESUMO
Porcine circovirus 3 (PCV-3) prevalence has been minimally investigated in wild boar; dynamics of infection and viral tissue distribution are currently unknown. In this study, serum samples from 518 wild boar (from years 2004 to 2018) were used to study frequency of infection. Also, serum samples from 19 boar captured and recaptured at least two times for a period of time from 1 month to 1 year were collected to determine PCV-3 infection dynamics. Finally, to elucidate PCV-3 DNA organic distribution, sera, different tissues and faeces were obtained from 35 additional wild boar. PCV-3 DNA was extracted and amplified with a conventional PCR. For the PCV-3 PCR-positive sera from the longitudinally sampled and different tissue types, a quantitative PCR was performed. Genome sequence was obtained from a number of PCV-3 PCR-positive samples from different years, different time-points of infection and tissues. Obtained results confirmed the susceptibility of wild boar to the virus, showing high frequency of PCV-3 detection (221 out of 518, 42.66%) and demonstrating circulation at least since 2004. Compiled data indicate the possibility of long-term infections, since 5 out of 10 PCV-3 PCR-positive boars longitudinally sampled showed positivity in samplings separated for more than 5 months. All tested tissue types' harboured PCV-3 genome, with the highest percentage of PCR positivity in submandibular lymph node, tonsil, lung, liver, spleen and kidney. The amount of DNA in all tested PCV-3 PCR-positive samples was moderate to low. All partial and complete PCV-3 sequences obtained from wild boar displayed high nucleotide identity, higher than 98%. In conclusion, this study further confirms that wild boar is susceptible to PCV-3 infection, showing high frequency of detection in this animal species. Furthermore, PCV-3 can be found in different tissues of wild boar and is apparently able to cause persistent infection.
Assuntos
Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Doenças dos Suínos/epidemiologia , Animais , Infecções por Circoviridae/sangue , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologia , Feminino , Masculino , Reação em Cadeia da Polimerase/veterinária , Prevalência , Estudos Retrospectivos , Espanha/epidemiologia , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/virologiaRESUMO
The Ecohealth strategy is a multidisciplinary data-driven approach used to improve the quality of people's lives in Chagas disease endemic areas, such as regions of Central America. Chagas is a vector-borne disease caused by the parasite Trypanosoma cruzi. In Central America, the main vector is Triatoma dimidiata. Because successful implementation of the Ecohealth approach reduced home infestation in Jutiapa department, Guatemala, it was scaled-up to three localities, one in each of three Central American countries (Texistepeque, El Salvador; San Marcos de la Sierra, Honduras and Olopa, Guatemala). As a basis for the house improvement phase of the Ecohealth program, we determined if the localities differ in the role of sylvatic, synanthropic and domestic animals in the Chagas transmission cycle by measuring entomological indices, blood meal sources and parasite infection from vectors collected in and around houses. The Polymerase Chain Reaction (PCR) with taxa specific primers to detect both, blood sources and parasite infection, was used to assess 71 T. dimidiata from Texistepeque, 84 from San Marcos de la Sierra and 568 from Olopa. Our results show that infestation (12.98%) and colonization (8.95%) indices were highest in Olopa; whereas T. cruzi prevalence was higher in Texistepeque and San Marcos de la Sierra (>40%) than Olopa (8%). The blood meal source profiles showed that in Olopa, opossum might be important in linking the sylvatic and domestic Chagas transmission cycle, whereas in San Marcos de la Sierra dogs play a major role in maintaining domestic transmission. For Texistepeque, bird was the major blood meal source followed by human. When examining the different life stages, we found that in Olopa, the proportion bugs infected with T. cruzi is higher in adults than nymphs. These findings highlight the importance of location-based recommendations for decreasing human-vector contact in the control of Chagas disease.
Assuntos
Doença de Chagas/transmissão , Doença de Chagas/veterinária , Insetos Vetores/fisiologia , Triatoma/fisiologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Doenças das Aves/parasitologia , Doenças das Aves/transmissão , Aves , América Central/epidemiologia , Doença de Chagas/sangue , Doença de Chagas/parasitologia , Doenças do Cão/sangue , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Comportamento Alimentar , Feminino , Habitação , Humanos , Ciência da Implementação , Insetos Vetores/parasitologia , Masculino , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Doenças dos Suínos/transmissão , Triatoma/parasitologia , Trypanosoma cruzi/fisiologiaRESUMO
Influenza A virus (IAV) causes an important respiratory disease in mammals and birds leading to concerns in animal production industry and public health. Usually, antibodies produced in mammals are employed in diagnostic tests. However, due to animal welfare concerns, technical advantages and the high cost of production, alternatives to the production of antibodies in mammals have been investigated. The aim of this study was to produce egg yolk immunoglobulin (IgY) in laying hens against a highly conserved protein (nucleoprotein- NP) of IAV and to evaluate the application of anti-NP IgY antibodies in virus detection by immunocytochemistry (ICC) and immunohistochemistry (IHC). Three laying hens of the White Leghorn line were inoculated seven times with a recombinant NP protein and their eggs collected seven days after the 3rd, 5th and 7th inoculations. Immunoglobulin Y antibodies were purified from egg yolk through precipitation with ammonium sulfate. The titers and specificity of the purified antibodies were determined by ELISA, western blotting, ICC and IHC. High levels of specific anti-NP antibodies were detected by ELISA after the 5th inoculation, reaching a peak after the 7th inoculation. The mean yield of total protein in yolk after the 7th inoculation was 13.5â¯mg/mL. The use of western blotting and ICC demonstrated that anti-NP IgY binds specifically to NP protein. Moreover, the use of anti-NP IgY antibody in ICC test revealed positive staining of MDCK cells infected with IAV of the three subtypes circulating in swine (H1N1, H1N2, and H3N2). However, no staining was observed in lung tissues through the IHC test. The data obtained showed that anti-NP IgY antibodies bound specifically to influenza virus NP protein, detecting the main virus subtypes circulating in swine, reinforcing their usefulness in the influenza diagnosis.
Assuntos
Anticorpos Antivirais , Imunoglobulinas , Vírus da Influenza A , Infecções por Orthomyxoviridae , Doenças dos Suínos , Proteínas do Core Viral , Animais , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Galinhas/imunologia , Cães , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imunoglobulinas/química , Imunoglobulinas/imunologia , Vírus da Influenza A/imunologia , Vírus da Influenza A/metabolismo , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/veterinária , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Proteínas do Core Viral/sangue , Proteínas do Core Viral/imunologiaRESUMO
In South America, wild populations of peccaries coexist with domestic and feral pigs, with poorly understood consequences. We captured 58 collared peccaries ( Pecari tajacu) and 15 feral pigs ( Sus scrofa) in locations of Colombia where coexistence of these species is known. Blood samples were tested for antibodies against four viral agents, classical swine fever virus (CSFV), Aujeszky's disease virus (ADV), porcine circovirus (PCV-2), and vesicular stomatitis virus (New Jersey and Indiana subtypes) and two bacterial agents, Brucella spp. and six serovars of Leptospira interrogans. The prevalence of CSFV was 5% (3/58) in collared peccaries and 7% (1/15) in feral pigs. The prevalence of PCV-2 was 7% (1/15) in collared peccaries and 67% (2/3) in feral pigs. Vesicular stomatitis prevalence was 33% (8/24) in collared peccaries and 67% (4/6) in feral pigs. Leptospira prevalence was 78% (39/50) in collared peccary and 100% (8/8) in feral pigs; bratislava, grippotyphosa, icterohaemorrhagiae, and pomona were the most frequent serovars. Also, the only white-lipped peccary ( Tayassu pecari) sampled was positive for L. interrogans serovar bratislava and for vesicular stomatitis virus, New Jersey strain. No samples were positive for ADV or Brucella. The seroprevalence of antibodies against L. interrogans was similar to that observed in other studies. Icterohaemorrhagiae appears to be a common serovar among in situ and ex situ peccary populations. Positive antibodies against PVC-2 represent a novel report of exposure to this pathogen in Colombian peccaries. Our results indicate the possible transmission of various pathogens, important for pig farms, in the studied pig and peccaries.
Assuntos
Infecções Bacterianas/veterinária , Doenças dos Suínos/sangue , Viroses/veterinária , Animais , Animais Selvagens , Artiodáctilos , Infecções Bacterianas/sangue , Infecções Bacterianas/epidemiologia , Colômbia/epidemiologia , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Viroses/sangue , Viroses/epidemiologiaRESUMO
Background: Hepatitis E virus (HEV) is the causative agent of acute hepatitis worldwide. There is no seroprevalence study in backyard farms, which are characterized by suboptimal hygienic conditions in Brazil. We aimed to determine the seroprevalence and genetic diversity of HEV in backyard pigs in Brazil. Methods: Swine serum samples collected in 2012 (n=731) and 2014 (n=713) were analysed. The presence of anti-HEV immunoglobulin G in pig serum was evaluated by indirect enzyme-linked immunosorbent assay. Reverse transcription polymerase chain reaction was performed and phylogenetic analyses were carried out based on the partial ORF1 and ORF2 coding regions. Results: Anti-HEV antibodies were detected in 77.6% (567/731; 95% confidence interval [CI] 74.5 to 90.6%) of serum samples in 2012 and 65.5% (467/713; 95% CI 62.0 to 69.0%) in 2014. The herd seroprevalence was 91.7% (187/204; 95% CI 91% to 99%) in 2012 and 83.7% (164/196; 95% CI 78% to 89%) in 2014. Further, HEV RNA was detected in 0.8% (6/713) of samples from 2014. Phylogenetic analysis showed three different genotype 3 subtypes with high similarity to human HEV strains. Conclusions: This study showed that backyard pigs are a reservoir of HEV and alerts us to the need to control infection and spillover from backyard farms. GenBank accession numbers: MF438128-MF438135.
Assuntos
Vírus da Hepatite E/isolamento & purificação , Hepatite E/veterinária , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/virologia , Zoonoses/transmissão , Zoonoses/virologia , Animais , Brasil , Culinária , Reservatórios de Doenças/veterinária , Reservatórios de Doenças/virologia , Ensaio de Imunoadsorção Enzimática , Variação Genética , Anticorpos Anti-Hepatite/genética , Hepatite E/sangue , Hepatite E/epidemiologia , Hepatite E/genética , Vírus da Hepatite E/genética , Abrigo para Animais/normas , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Carne/virologia , Filogenia , Saneamento/normas , Estudos Soroepidemiológicos , Suínos/virologia , Doenças dos Suínos/sangue , Doenças dos Suínos/transmissão , Zoonoses/prevenção & controleRESUMO
Porcine circovirus 2 (PCV2) is associated with a series of swine diseases. There is a great interest in improving our understanding of the immunology of PCV2, especially the properties of the viral capsid protein Cap-PCV2 and how they relate to the immunogenicity of the virus and the subsequent development of vaccines. Phage display screening has been widely used to study binding affinities for target proteins. The aim of this study was to use phage display screening to identify antigenic peptides in the PCV2 capsid protein. After the selection of peptides, five of them presented similarity to sequences found in cap-PCV2, and four peptides were synthesized and used for immunization in mice: 51-CTFGYTIKRTVT-62 (PS14), 127-CDNFVTKATALTY-138 (PS34), 164-CKPVLDSTIDY-173 (PC12), and 79-CFLPPGGGSNT-88 (PF1). Inoculation with the PC12 peptide led to the highest production of antibodies. Furthermore, we used the PC12 peptide as an antigen to examine the humoral response of swine serum by ELISA. The sensitivity and specificity of this assay was 88.9% and 92.85%, respectively. Altogether, characterization of immunogenic epitopes in the capsid protein of PCV2 may contribute to the improvement of vaccines and diagnostics.
Assuntos
Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Técnicas de Visualização da Superfície Celular , Circovirus/imunologia , Peptídeos/imunologia , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/química , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/virologia , Circovirus/química , Circovirus/genética , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Epitopos/imunologia , Epitopos/isolamento & purificação , Camundongos , Testes de Neutralização , Peptídeos/química , Peptídeos/isolamento & purificação , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/sangue , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Vacinas Virais/imunologiaRESUMO
The lentil lectin glycoprotein enzyme-linked immunoelectrotransfer blot (LLGP EITB, reported sensitivity 99% and specificity 100%) is used as a serologic marker of exposure to Taenia solium in pigs. However, only a limited number of parasites have been evaluated for cross reactivity. Pigs may host other related cestode infections, including Taenia hydatigena, which have not been formally evaluated for cross-reactions. We investigated a corral in Tumbes, Peru, a region where a cysticercosis elimination demonstration project was completed in 2012. In this corral, 14/19 (73.7%) 6-8-week-old piglets were reactive to GP50 on LLGP EITB, and all had circulating Taenia sp. antigens. From eight necropsied piglets; four were infected with T. hydatigena metacestodes whereas none had evidence of T. solium infection. Two resident dogs were subsequently confirmed to have T. hydatigena taeniasis. These results suggest GP50 cross-reactivity in T. hydatigena-infected pigs, although controlled experimental infection is needed to confirm this hypothesis.