José Givanildo da Silva

Detection of Toxoplasma gondii in the milk of naturally infected goats in the Northeast of Brazil

The aim of the present study was to detect the genomic DNA of Toxoplasma gondii in milk samples from naturally infected goats in the state of Pernambuco, (Brazil). In total, 248 blood serum samples were collected and processed from lactating goats and then submitted to a search for antibodies to T. gondii through the indirect immunofluorescence reaction. Samples with a score of 64 or more were considered positive. In total, 248 milk samples were collected and processed from the same group of goats in order to study the DNA of T. gondii using the polymerase chain reaction (PCR) technique. In the serum samples, 56/248 (22.58%) of the animals were positive, whereas the DNA of the parasite was detected in 15/248 (6.05%) of the milk samples. Five of these 15 samples were animals who were also positive in the serology. This study reports the first occurrence of the elimination of T. gondii from the milk of naturally infected goats in the north-east of Brazil. It is suggested that the consumption of in natura goat milk may constitute a potential risk to the health of milk consumers in this region.

Occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in raw milk of sheep and goats of local breeds reared in Northeastern Brazil

The aim of the present study was to detect Toxoplasma gondii DNA in raw milk samples of goats and sheep of local breeds from the semi-arid region of the states of Pernambuco and Paraíba, Northeastern Brazil. Serum and milk samples were collected from 243 animals (186 goats and 57 sheep). The Indirect fluorescent antibody test (IFAT) was used to search for anti-T. gondii IgG antibodies with a cutoff of 64. Subsequently, the raw milk samples were subjected to DNA extraction and PCR to detect DNA of T. gondii. The IFAT results showed a 6.58% (16/243) positivity when all the samples were considered and a positivity of 15.78% (9/57) and 3.76% (7/186) for goats and sheep samples, respectively. The PCR assay detected T. gondii DNA in 2.06% (5/243) of all the samples tested. All the PCR positive samples were from goats. This result shows the importance of adopting measures of flocks sanitary management and avoiding the consumption of raw milk may constitute a potential risk to the health of milk consumers in this region.

High prevalence of toxoplasmosis in free-range chicken of the Fernando de Noronha Archipelago, Brazil

The present study aimed to determine the prevalence of toxoplasmosis in free-range chickens of the Fernando de Noronha Archipelago, Brazil and to identify risk factors associated with Toxoplasma gondii infection. Blood samples were collected from all the adult chickens raised in the Archipelago and screened by Indirect Fluorescent Antibody Test (430 samples, in total). Univariate analysis (Chi-square) and logistic regression were used to investigate the relationship between various variables possibly predictive of an increased likelihood of T. gondii infection. The overall prevalence of T. gondii infection in chickens of the Fernando de Noronha Archipelago was 88.4% (380/430; 84.6%-91.0%; 95% CI), ranging from 57.1% to 100.0% among the studied properties. The risk factors associated with T. gondii infection were the number of domestic cats in the properties (p=0.022), the presence of feral cats (p=0.006) and the presence of an open water source (p=0.046). Domestic and feral cats should be prevented from accessing the water and food supplied to chickens.

Incidence and vertical transmission rate of Neospora caninum in sheep

The infection by Neospora caninum in sheep can lead to abortion and the birth of weak and debilitated lambs. The aim of this study was to assess the incidence of natural infection by Neospora caninum and the vertical transmission rate among sheep. A flock of 50 sheep was monitored for serum antibody titres against N. caninum and seroconversion over a period of six months using an indirect ELISA technique. The offspring of the herd was also investigated regarding anti-N. caninum antibodies to determine the vertical transmission rate through the indirect immunofluorescence technique. The initial and final prevalences of infection by N. caninum were 26.0% (13/50) and 72.0% (36/50), respectively, and the incidence of infection by N. caninum in the present study was 62.2% (23/37). The vertical transmission rate found was 15.4% (2/13). A high incidence of infection by N. caninum in sheep was observed, and this is the first report assessing the incidence of N. caninum among naturally infected sheep.

Occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chicken breeding in Northeast, Brazil

The aim of the present study was to investigate the occurrence of anti-Toxoplasma gondii antibodies and parasite DNA in backyard chickens bred in the metropolitan area of Recife, Brazil. In total, 212 serum samples were collected from 16 properties, and 12 backyard chickens were collected in the six sanitary districts of Recife. An indirect immunofluorescence assay (IFA) was used to investigate the occurrence of anti-Toxoplasma gondii antibodies. Polymerase chain reaction (PCR) was used to detect T. gondii DNA in brain, heart, liver and lung specimens. Of the samples analyzed by serology, 86/212 (40.56%) were positive; of the samples analyzed by PCR, 2/12 (16.7%) were positive, with both samples positive by both tests (serological and molecular). The presence of antibody anti-T. gondii and parasite DNA in tissues of these animals are worrying aspects for public health because there is a risk of transmission of the parasite to humans through eating undercooked or raw meat. Based on the results, the adoption of preventive measures to prevent the cats access to the chickens creations should be encouraged, since these animals were identified in most of the studied properties.

Mycoplasma agalactiae in semen and milk of goat from Pernambuco state, Brazil

In goat and sheep flocks, mycoplasmosis is a disease that may cause severe economical losses associated with polyarthritis, mastitis, agalactia, conjunctivitis, pneumonia and reproductive failure. The latter may involve repeat breeding, granular vulvovaginitis, infertility and abortions. The aim of the present study was to assess the occurrence of Mycoplasma agalactiae (Ma) in semen and milk samples from naturally infected goat in the semiarid region from Pernambuco State, Northeast from Brazil. Thirty-nine semen samples and 81 milk samples were submitted to DNA extraction using a commercially available kit and following the manufacturers instructions. The polymerase chain reaction (PCR) was then performed in accordance with protocols described in the literature. The results of the present study revealed the presence of Ma in the DNA of 17.9% (7/39) of the semen samples and 3.7% (3/81) of the milk samples. The results obtained in the present study confirm the elimination of the DNA of Ma in the semen and milk samples. The presence of this agent in goat flocks is considered very risky in terms of reproductive disorders and contagious agalactia outbreaks in the Northeast region of Brazil.

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 homade 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 Toxoplasma gondii DNA in sheep naturally infected and slaughtered in abattoirs in Pernambuco, Brazil

The aim of the present study was to assess the occurrence of antibodies to Toxoplasma gondii and to detect genomic DNA of the parasite in the reproductive organs, fetuses and fetal membranes of sheep in slaughterhouses in the state of Pernambuco, Brazil. The Indirect Immunofluorescence technique (IFA) was used for screening. The Polymerase Chain Reaction (PCR) was used to detect DNA of T. gondii in the animals that were positive in the serology. In the serology, 13/50 samples were positive and genomic DNA of T. gondii was detected in one uterus, tube, ovary, placenta and fetus (heart, brain and umbilical cord) sample from a sheep that was positive in the serology. The present study provides evidence of the occurrence of T. gondii DNA in the organs of the reproductive system, placenta and fetus of a naturally infected sheep.

Anti-Neospora caninum antibodies in feral cats on the Island of Fernando de Noronha, Brazil

Neospora caninum is a protozoan responsible for abortions, stillbirths (mainly among cattle) and neuromuscular diseases in dogs. Its importance in wild species and its impact on the environmental preservation of different ecosystems have been little described. This study aimed to investigate the presence of anti-N. caninum antibodies in feral cats on the island of Fernando de Noronha and contribute epidemiological data on this disease in these animals and its impact on the environmental preservation of the island. Serum samples from 257 feral cats on the island were analyzed through the Neospora agglutination test (NAT) to search for anti-Neospora caninum antibodies. Among the 257 serum samples analyzed, 8 (3.11%) were positive in the NAT. The antibody titers were 20 in seven animals (87.5%) and 40 in one animal (12.5%). These results demonstrate that feral cats are exposed to infection by N. caninum on the island of Fernando de Noronha, at a low frequency. Greater knowledge on this infection in this animal species in this insular environment is important for elucidating its impact on the conservation of species and the maintenance of this parasite on the island.