Epitope mapping and a candidate vaccine design from canine distemper virus.

Background: Canine distemper (CD) is a worldwide spread disease that has been described in 12 families of mammals, especially in the Carnivora order, being better studied in domestic canines where vaccination represents the best means of control. CD is controlled by vaccination, but many cases of the disease still occur in vaccinated animals. Aim: The aim of this work was to study antigen-specific epitopes that can subsidize the development of a new vaccine approach. Methods: Mapping of T cell reactive epitopes for CD virus (CDV) was carried out through enzyme-linked immunospot assays using 119 overlapped synthetic peptides from the viral hemagglutinin protein, grouped in 22 pools forming a matrix to test the immune response of 32 animals. Results: Evaluations using the criteria established to identify reactive pools, demonstrated that 26 animals presented at least one reactive pool, that one pool was not reactive to any animal, and six pools were the most frequent among the reactive peptides. The crisscrossing of the most reactive pools in the matrix revealed nine peptides considered potential candidate epitopes for T cell stimulation against the CDV and those were used to design an in-silico protein, containing also predicted epitopes for B cell stimulation, and further analyzed using immune epitope databases to ensure protein quality and stability. Conclusion: The final in silico optimized protein presents characteristics that qualify it to be used to develop a new prototype epitope-based anti-CDV vaccine.

First serological diagnosis of Mycobacterium avium subsp. paratuberculosis infection in sheep in the state of Pernambuco, Brazil.

This study aimed to diagnose Mycobacterium avium subsp. paratuberculosis (MAP) infections in sheep in the state of Pernambuco, Brazil. A total of 276 blood samples were analyzed using the enzyme-linked immunosorbent assay IDEXX Paratuberculosis Screening kit, and 261 fecal samples were submitted for bacterial culture and polymerase chain reaction tests. An animal-level sero-frequency of 0.72% (n = 2/276) and a farm-level sero-frequency of 20% (n = 2/10) were found. All fecal sample cultures were negative, and molecular analyses were also negative. To the best of our knowledge, this is the first study of MAP infection in sheep in the state of Pernambuco and one of the pioneers in the country. It is an asymptomatic disease that is difficult to diagnose in this species because the susceptibility of sheep to the organism is lower than that of other ruminant species. However, the sero-frequency found reveals that there is MAP exposure in sheep flocks in the region. In addition, serological monitoring can contribute to the observation of the organism's behavior in herds. Our results support the potential risk of MAP infection in sheep in the state of Pernambuco, Brazil.

Occurrence of extended-spectrum ß-lactamase-producing Enterobacteriaceae in raw milk from cows with subclinical mastitis in northeast Brazil.

Extended-spectrum ß-lactamase (ESBL)-producing Gram negative bacteria are becoming increasingly important in veterinary and human medicine because they can hydrolyze the third generation ß-lactams, penicillins, and monobactams. The aim of this study was to identify ESBL-producing Enterobacteriaceae in raw cow milk samples from northeast Brazil. Twenty-six bacterial isolates belonging to the Enterobacteriaceae family were obtained from milk samples from 257 cows with subclinical mastitis. Using microbiological tests, 53.85% (14/26) were identified as Escherichia coli, 15.38% (4/26) as Proteus mirabilis, 26.92% (7/26) as Klebsiella spp., and 3.85% (1/26) as Citrobacter spp. Of all the isolates, 61.54% (16/26) were positive in the ESBL screening test, of which 12.5% (2/16) were positive in the double-disc synergy test using three types of cephalosporins and amoxicillin/clavulanic acid. The two isolates were identified as Klebsiella spp. Among all the isolates, 53.85% (14/26) were positive for one or both ESBL-encoding genes, blaSHV and blaTEM; among these, 71.43% (10/14) were identified as E. coli. This study demonstrates that ESBL-producing bacteria can be found in raw cow milk from northeast Brazil. Cows with subclinical mastitis should be recognized as reservoirs of these strains, which can propagate to humans.

Current status of glanders in Brazil: recent advances and challenges.

Glanders is an infectious disease that causes serious damage to the equine production chain in countries where it occurs endemically and poses a risk to public health. This study aimed to conduct an integrative review of the advances in the knowledge of glanders in Brazil over the last three decades since its re-emergence. Documentary research was conducted for the period between the years 2000 and 2022. SCOPUS and PUBMED databases were used to search for scientific articles, dissertations, and thesis, in addition to the Brazilian Digital Library of Thesis and Dissertations (BDTD). A total of 41 documents were retrieved, including 12 dissertations, five theses, and 24 scientific articles. The Federal Rural University of Pernambuco (UFRPE) group provided a noteworthy amount of material on this topic (25 documents, four theses, three dissertations, and 18 scientific articles). During this period, ten dissertations, one thesis, and six scientific articles published by other groups in other states of the Federation were also identified. It was concluded that there was a significant number of scientific publications with relevant data on the clinical, epidemiological, pathological, microbiological, serological, and molecular characteristics of glanders disease in Brazil. Additionally, training of human resources regarding this disease led to an increase in the nucleation of research groups, especially in the northeast region of Brazil. Despite significant advances, new research groups and specific funding are still needed for the development of more accurate diagnostic methods, immunizing production, training of veterinarians to recognize the disease, and more robust programs to control and eradicate the disease in Brazil.

Toxoplasma gondii infection in goats: serological, pathological, and clinical monitoring during gestation.

This study aimed to evaluate Toxoplasma gondii infection in pregnant goats. The goats were divided into two groups: group one (G1) comprised of 31 pregnant goats naturally infected with T. gondii, and group two (G2) comprised of seven uninfected pregnant goats from a flock with a history of abortion due to toxoplasmosis. Serological investigation, ultrasonography, and clinical testing were performed on all goats during gestation. Serum samples from goats and their offspring (precolostral) were collected to evaluate the vertical transmission of T. gondii. Samples from placentas and aborted fetuses were also collected for molecular and histopathological analysis. Results showed that in G1, estrus recurrence occurred in 22.6% (7/31) of the goats, embryonic death in 3.3% (1/31), and abortion in 19.4% (6/31). An increase in anti-T. gondii antibodies was observed in G1 goats at day 150 of pregnancy. T. gondii DNA was detected in 42.8% (3/7) of aborted fetuses and was associated with histopathological lesions caused by this parasite. Moreover, toxoplasmosis in field conditions caused by genotype ToxoDB #1 in pregnant goats resulted in severe reproductive loss in the flock.

Occurrence of emerging multiresistant pathogens in the production chain of artisanal goat coalho cheese in Brazil.

Sanitary-hygienic failures in cheese making can pose health risks to consumers. This study aimed to identify multiresistant pathogens in different production stages of artisanal goat coalho cheese in Brazil and characterize their phenotypic and genotypic resistance. Eleven properties in the state of Pernambuco, Brazil, participated in the study. Samples were obtained from different stages of production and the humans involved. The samples obtained were submitted to microbiological culture, then all the isolated microorganisms were submitted to the Matrix Associated Laser Desorption-Ionization - Time of Flight technique for the microbiological identification of the species. Subsequently, Staphylococcus spp., Enterococcus spp. and Macrococcus caseolyticus were subjected to polymerase chain reaction to search for resistance genes and disc diffusion technique to evaluate the resistance profile. A total of 111 isolates were obtained and 31 species were identified, with the frequency of Staphylococcus spp. (62.20%; 69/111), Enterococcus spp. (11.60%; 13/111), Macrococcus caseolyticus (10%; 11/111), Bacillus spp. (3.60%; 4/111), Enterobacter spp. (3.60%; 4/111), Aureobasidium pullulans (1.80%; 2/111), Corynebacterium camporealensis (1.80%; 2/111), Issatchenkia occidentalis (1.80%; 2/111), Kocuria kristinae (1.80%; 2/111), Aerococcus viridans (0.90%; 1/111) and Filifactor villosus (0.90%; 1/111). Phenotypic and genotypic resistance was also detected with the occurrence of 15.90% (7/44) of the mecA gene, 4% (1/25) vanA, and 4% (1/25) vanB in Staphylococcus spp. and 20% (2/10) vanB in and Enterococcus spp. Emerging multiresistant pathogens are present in the production chain of artisanal goat cheese and humans, who exert an important role in disseminating these bacteria with imminent risks to human health.

Occurrence of serological reactions for serogroup Sejroe (CTG and Prajtino) in female buffalo in the state of Pernambuco, Brazil.

The objective of this study was to evaluate the occurrence of anti-Leptospira spp. antibodies in female buffalo in the state of Pernambuco. A total of 123 female buffalo blood samples were collected from five properties distributed in the state of Pernambuco. The microscopic agglutination test was used to study anti-Leptospira spp. antibodies. The occurrence of anti-Leptospira spp. antibodies was 28.5% (35/123; CI 20.7-37.3%) and on different properties, the occurrence ranged from 28.6% to 80.0%, with 100% of the properties showing animals with positive results. The serovars of the serogroup Sejroe with a higher incidence were Hardjoprajtino (CTG strain, 49.1%) and Hardjo (Prajtino genotype, 43.2%), followed by serogroup Grippotyphosa with the Grippotyphosa serovar (3.9%), serogroup Pomona with the Pomona serovar (1.9%), and the Icterohaemorrhagiae serovar Copenhageni (1.9%). This was the first record of the occurrence of anti-Lepstospira spp. antibodies in female buffalo in the state of Pernambuco. Control measures are necessary to prevent health and economic losses, given that the agent involved affects animal reproduction, triggering drops in conception rates or even clinical cases of abortion.

Prevalence and risk factors associated with Tritrichomonas foetus infection in cattle in the state of Paraíba, Brazil.

The objective of this study was to determine the prevalence of Tritrichomonas foetus infection and to evaluate risk factors associated with this infection among cattle in the state of Paraíba in northeastern Brazil. Samples of cervicovaginal mucus from 290 females and smegma from 59 males [beef, 31; mixed aptitude (beef and dairy), 10; and dairy, 18] from 31 farms were collected. Modified Diamond's medium and polymerase chain reaction (PCR) were used for the laboratory diagnosis of T. foetus infection. Univariate analysis and logistic regression were performed to test for potential risk factors in addition to prevalence mapping. No sample was positive for T. foetus in culture, and the prevalence of T. foetus infection using PCR was 3.7% (13/349) [confidence interval (CI) 95%, 2.1%-6.4%]. In total, 19.3% (6/31) of the farms had at least one animal positive for T. foetus. The contact of females with males from other farms [Odds ratio, 5.9; 95% CI, 1.5-22.4; p = 0.009] was identified as a risk factor for T. foetus infection. This study demonstrates that T. foetus infection is prevalent among dairy cows in the state of Paraíba, Brazil. Sexual resting, removal of positive females, and avoiding contact of females with males from other farms are recommended to reduce the risk of infection.

Risk Analysis and Occurrence of Hepatitis E Virus (HEV) in Domestic Swine in Northeast Brazil.

Anti-HEV antibodies were detected in animals from abattoir and in farms from northeast Brazil. Our results suggest that HEV is highly disseminated in the swine population and might present a great risk to animal handlers and for consumption of raw or undercooked meat and meat products in northeast Brazil.

Detection of Mycobacterium avium subsp. paratuberculosis in bovine milk from the state of Pernambuco, Brazil.

The aim of this study was to detect the IS900 region of Mycobacterium avium subsp. paratuberculosis (MAP) in bovine milk samples using real-time polymerase chain reaction (qPCR) and conventional PCR, and to study the agreement between these tests. A total of 121 bovine milk samples were collected from herds considered positive for MAP, from the State of Pernambuco, Brazil. MAP DNA was detected in 20 samples (16.5%) using conventional PCR and in 34 samples (28.1%) using qPCR. MAP DNA was detected in all of the 6 animal farms studied. Moderate agreement was found between qPCR and conventional PCR results, where the sensitivity and specificity of conventional PCR in relation to qPCR were 50% and 96.6%, respectively. Thus, the IS900 region of MAP was found in bovine milk samples from the State of Pernambuco. To the best of our knowledge, this is the first report of MAP DNA found in bovine milk in Northeast Brazil. We also demonstrated the qPCR technique is more sensitive than conventional PCR with respect to detection of MAP in milk samples.

Occurrence of Toxoplasma gondii in domestic rabbits of Northeastern Brazil.

The present study aimed to conduct a serosurvey of toxoplasmosis in domestic rabbits of Northeastern Brazil. Blood samples and tissue fragments (brain, heart and diaphragm) were collected from 150 and 54 rabbits from the state of Pernambuco, Brazil, respectively. The serum samples were subjected to serological analysis (Modified Agglutination Test - MAT) and the tissue samples were assessed by PCR and histopathological analysis. Data collected through questionnaires were subjected to analysis of risk factors. According to the MAT and the PCR results, 6.7% (10/150; CI 3.2%-11.9%) of the rabbits were positive for anti-T. gondii antibodies and 9.25% (5/54) of the tissue fragments were positive for T. gondii DNA, respectively. Lesions associated with T. gondii infection, mainly characterized by granuloma, mononuclear cell infiltrates, degeneration areas and necrosis in brain and heart, were detected in the histopathological analysis. The risk factors associated with T. gondii infection identified in the present study were homemade food (odds ratio = 39.00) and contact between cats and rabbits (odds ratio = 52.00). This is the first report of toxoplasmosis in rabbits of Northeastern Brazil. The management problems identified in the present study must be corrected to reduce the frequency of positive animals in herds of rabbits.

Occurrence of antibodies to Toxoplasma gondii in mules and donkeys in the northeast of Brazil.

The aim of the present study was to investigate antibodies to Toxoplasma gondii in the serum of mules and donkeys bred in the northeast of Brazil. In total, 483 samples were used (395 mules and 88 donkeys) from 4 states (Pernambuco, Rio Grande do Norte, Paraíba, and Sergipe). The indirect immunofluorescence reaction (IFI) technique was used to investigate antibodies to T. gondii with a cut-off point of 64. Positive frequencies of 23.8% and 43.2% were recorded for mules and donkeys, respectively. The state of Pernambuco had the highest prevalence of positive samples (29%) with statistically significant differences for species (P < 0.001) and state (P = 0.048). This is the first study of antibodies to T. gondii in mules and donkeys in these 4 states of the northeastern region of Brazil and serves as a warning to health authorities regarding the risks of ingesting equine meat.

Glanders in donkeys (Equus Asinus) in the state of pernambuco, Brazil: A case report.

The clinical, anatomical and histopatological findings of glanders diagnosis in donkeys in the state of Pernambuco-Brazil are reported. The animals were euthanized and necropsied, and evaluated for lesions in respiratory and lymphatic systems, confirming the disease by isolation of Burkholderia mallei and Strauss test.