Mycobacterium avium subsp. paratuberculosis (MAP) in goat milk in the semiarid region of the Brazilian Northeast - molecular characterization

Background: Goat farming has been on the rise in Brazil in recent years. Overall, 93% of the national herd is concentrated in the Northeast, with the state of Paraíba being the largest goat milk producer in the country. Considering Mycobacterium avium subsp. paratuberculosis (MAP) as a sanitary issue for the development of animal farming with risks for human health and that is a notifiable disease, this research was structured with the objective of confirming the presence and performing a molecular characterization of MAP in goat milk destined for processing plants in the semiarid region of the Brazilian Northeast. Materials, Methods & Results: Samples from 179 production units and 5 collective bulk tanks and 4 samples of pasteurized goat milk were analyzed through Real-time polymerase chain reaction (qPCR). Genetic material (DNA) for MAP was found in the goat milk sample from 1 production unit (1/179). From this positive sample, 9 lactating goats were identified in the original property, 7 of which showed MAP DNA in milk samples (77.77%). The characterization of the nucleotide sequence detected in the positive sample has 99% identity with KJ173784. Discussion: One sample (1/179), from the production units, had MAP genetic material (DNA) detected using the molecular test. Samples from these production units represent the milk from all lactating goats from each producer. Therefore, it was possible to identify from which farm the samples originated, allowing individual animals to then be tested, with milk samples collected from 9 goats and MAP DNA detected in 7 of them (77.77%) via PCR. Control and/or prevention programs need this type of surveillance in reason that it allows the tracking of possible foci from milk samples collected from dairy products or cooling stations. The use of PCR to detect MAP foci via goat milk is thus advantageous because samples are obtained in a non-invasive manner, with faster results when compared to the culture technique. The low detection via PCR in goat milk may be related to factors such as the small amount of MAP eliminated and the intermittent excretion in asymptomatic animals, as also false-positive samples. Samples from the collective bulk tanks was negative. It is possible that the combination of milk from all the properties diluted the amount of MAP. This suggests that the sensitivity of the PCR can be improved if the samples are obtained from the pooled milk from the same property. In some regions of Brazil, for example, showed the frequency of Zona da Mata region of the state of Minas Gerais, Brazil, found 1.94% of positive samples (9/464) and 9.76% (4/41) of properties with at least 1 positive sample for MAP. Different results to what were found in the semiarid region of Paraíba, where climate and production characteristics are different. Goats are susceptible to 3 strains: type "S" (Sheep), "Bison type" and type "C" (Cattle). Previous contact with this species may explain the similarity between the strain found in goat milk and those detected from bovine samples. This must also be taken into consideration during diagnosis and upon implementation of control measures for paratuberculosis in goats. Mycobacterium avium subsp. paratuberculosis was recorded for the first time in goat milk in the semiarid region, which may reveal a potential biological risk to humans and suggests the need for active surveillance of the agent.

Leptospira spp. of the urinary tract of female carrier goats in semi-arid conditions

Background: Leptospirosis is an important infectious disease in goat farming, with a worldwide distribution. It is usually transmitted by rodents and the genital route, may cause reproductive losses, negatively impacting goat farming. The diagnosis lies on serological, molecular and isolation techniques. Considering the importance of this disease for small ruminants, this work aimed to evaluate the serological, molecular findings and isolation of pathogenic leptospires in the urinary tract (kidney and bladder tissues) of goats. Materials, Methods & Results: Thirty-four adult goats were used for slaughter. Renal samples (n = 34), bladder (n = 34), were collected for isolation of the agent and molecular detection of Leptospira sp. and blood samples (n = 34) for serological testing. The polymerase chain reaction (PCR) was used as a molecular test and the microscopic serum agglutination test (MAT) was used as a serological test. Samples with DNA amplification were subjected to genetic sequencing. The presence of Leptospira DNA was found in the tissues of 8 (23.4%) goats, and of these, only 2 were positive in PCR and MAT. There was a slight agreement between the PCR and MAT techniques (k = 0.150; P = 0.436). In 6 (17.6%) samples of renal tissue and 2 (5.8%) bladder samples, Leptospira DNA was detected. The genes in a kidney tissue sample were sequenced and demonstrated 99% similarity to Leptospira interrogans. Anti-Leptospira sp. were detected in 6 (17.6%) of the animals tested. Discussion: Serology identified 3 predominant serogroups: Icterohaemorrhagiae, Tarassovi and Autumnalis, serogroups that are related to the presence of rodents that coexist in rural environments. Autumnalis has been reported in small ruminants, raising the hypothesis that goats are adapted, becoming chronic carriers and possible maintenance hosts. The frequency obtained (17.6%) may be the result of the mixed breed pattern and rustic characteristics inherent to the goat species. Given the characteristics of the semi-arid region, such as low rainfall and high solar incidence, it is essential to use an adapted methodology, with a lower cut-off point (1:50), as the serological titer is an established relationship between the animal species, the level of exposure throughout its evolution and the region studied. Molecular findings and bacterial isolation reveal the agent's ability to colonize the urinary tract of goats. These data show the importance that urine has in the epidemiological chain, being able to transmit the agent through direct contact with this product or through contamination of soil and water. There was no statistical agreement between the diagnostic techniques used in this study, in this case, an association between PCR and MAT is recommended to obtain data with high sensitivity and specificity. A bladder sample was sequenced and showed 99% similarity to Leptospira interrogans. In the semiarid region, the most common form of leptospirosis spread is through the sale of animals in business fairs for breeding, rearing or slaughter, as well as sharing the same property with several breeders. The introduction of chronic and asymptomatic carriers on the properties represents a serious risk for the spread of the disease. The results show the presence of Leptospira spp. in semi-arid goat herds, having as risk factors the presence of rodents and intercropping. The association of MAT and PCR is necessary for a better diagnosis of the disease.

Molecular detection of Leishmania infantum in donkeys and mules under semiarid conditions in Brazil / Detecção molecular de Leishmania infantum em asininos e muares sob condições semiáridas

Abstract Visceral leishmaniasis is a parasitic zoonosis that mainly affects poorest and most vulnerable populations, and domestic dogs are considered to be the main source of infection to the vector and therefore humans. However, several studies have investigated the role of other vertebrate hosts in the disease cycle. In this context, the aim of the present study was to conduct a survey of Leishmania infantum infection in donkeys and mules living in a semiarid region of Brazil. Whole blood sampled from 72 equids (65 donkeys and 7 mules) was used to perform molecular diagnosis using the real-time polymerase chain reaction (qPCR) technique. A total of 25% of the samples (18/72) were positive through qPCR, but there were no significant differences between the species (donkeys or mules), sex (male or female) and abandonment situation of the animals (yes or no). Donkeys and mules living under semiarid conditions have high frequency of L. infantum infection. It is therefore worth assigning importance to these species in the epidemiological cycle of visceral leishmaniasis, either as potential reservoirs or just as an abundant food source for vectors.

Resumo A leishmaniose visceral é uma zoonose parasitária que afeta principalmente populações mais pobres e vulneráveis, e os cães domésticos são considerados as principais fontes de infecção para o vetor e, portanto, para os humanos. Porém diversos estudos têm pesquisado o papel de outros hospedeiros vertebrados no ciclo da doença. Neste contexto, objetivou-se realizar um levantamento da infecção por Leishmania infantum em asininos e muares, vivendo em região semiárida do Brasil. Foi utilizado sangue total de 72 equídeos (65 asininos e 7 muares) para a realização de diagnóstico molecular por meio da técnica de Reação em Cadeia de Polimerase em Tempo Real (qPCR). Um total de 25% das amostras (18/72) resultaram positivas na qPCR, porém não houve diferença significativa entre as espécies (asininos e muares), sexo (macho e fêmea) e situação de abandono dos animais (sim ou não). Asininos e muares, vivendo em condições semiáridas, apresentam alta frequência de infecção por L. infantum, sendo válido atribuir importância a essas espécies no ciclo epidemiológico da leishmaniose visceral, seja como um reservatório em potencial, seja apenas como uma fonte alimentar abundante para os vetores.

Leptospira interrogans infection in tegu lizard (Tupinambis merianae), Brazil / Infecção por Leptospira interrogans em lagarto teiú (Tupinambis merianae), Brasil

We used 12 tegu lizards (Tupinambis merianae) from northeastern Brazil, and we reported nine (75%) Leptospira sp. PCR-positive animals and six (50%) seropositive. Leptospira sp. DNA sequencing revealed 99% similarity with L. interrogans. Our findings indicated that this species may play a role in the transmission of human leptospirosis.(AU)

Foram utilizados 12 lagartos Teiús (Tupinambis merianae) do Nordeste do Brasil. Encontramos nove animais positivos (75%) para Leptospira sp. na PCR e seis (50%) soropositivos. O sequenciamento de DNA de Leptospira sp. revelou 99% de semelhança com L. interrogans. Os resultados indicam que esta espécie pode desempenhar um papel importante na transmissão da leptospirose humana.(AU)