The occurrence and distribution of antibodies against Sarcocystis neurona, Neospora caninum and Toxoplasma gondii was investigated in horses, dogs and cats from Curitiba, Paraná state, Brazil. Serum samples were selected from 100 horses, 100 dogs and 100 cats from the routine of the Veterinary Clinical Pathology Laboratory in the Veterinary Hospital of the University of Paraná (UFPR). The 100 dog samples were divided into two groups: 35 samples from dogs with neurological sign (convulsion) and 65 samples from dogs without neurological signs. The animals were adults of different breeds, males and females. Samples were analyzed by indirect fluorescent antibody test (IFAT) for protozoa S. neurona, N. caninum andT. gondii at the following cut-off dilutions: horses: 1:50, 1:50 and 1:16; dogs: 1:50, 1:50 and 1:16; cats: 1:50, 1:50 and 1:50, respectively. The obtained results were 42% of horses, 7% of dogs and 5% of cats seropositive for S. neurona; 58% of horses, 68% of dogs and 42% of cats seropositive to N. caninum, and 36% of horses, 20% of dogs and 21% of cats seropositive for T. gondii. Among the dogs with neurological signs, 8.6%, 68.6% and 25.7% were seropositive for S. neurona, N. caninum and T. gondii, respectively. Among the dogs without neurological signs, 6.2% 67.7% and 16.9% were seropositive for S. neurona, N. caninum and T. gondii, respectively. No statistical difference was found between groups of seropositive dogs for the three protozoa with neurological signs and without neurological signs. Co-infection and high antibody titers were detected. The antibodies against Sarcocystis neurona, Neospora caninum and Toxoplasma gondii were found widely distributed among horses, dogs and cats in the region of Curitiba, state of Paraná, Brazil. 

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Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are obligate intracellular parasites within the phylum Apicomplexa. The red-tailed Amazon parrot (Amazona brasiliensis) is a near-threatened species of psittacine that is endemic to the Atlantic Forest of Brazil and has been designated as a bioindicator because of its sensitivity to environmental qualitative status and changes. The aim of this study was to evaluate the presence of antibodies against T. gondii, N. caninum and S. neurona in wild red-tailed Amazon parrot nestlings on Rasa Island, Brazil. Blood samples were collected from 51 parrots and plasma samples were stored at – 20 °C until immunofluorescence antibody tests (IFAT) were performed. Antigen slides were prepared using tachyzoites of T. gondii (RH strain) and, N. caninum (NC-1 strain) and using merozoites of S. neurona (SNR37 strain). Plasma samples were tested at initial dilutions of 1:16 for T. gondii, 1:50 for N. caninum and 1:5 for S. neurona. An anti-chicken antibody conjugated with FITC was used as a secondary antibody at 1:50 dilution. No antibodies for any of these three protozoa were found, thus suggesting that these wild red-tailed Amazon parrot nestlings had not been exposed to these parasites.

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Important physiological changes affect the blood profile of ruminants during the growth phase, but few studies approach the factors involved in these dynamics in lambs. The aim of this study was to characterize the dynamics of hematological parameters, of total plasma protein (TPP), and of fibrinogen in healthy female lambs during the first four months of life. Blood samples of 35 female lambs were collected at 30, 60, 90, and 120 days old to perform the complete blood count (CBC). The erythrocyte and leukocyte parameters, TPP, and fibrinogen were determined. The means for total red blood cell (RBC) counts at 60 and 120 days differed (P < 0.05) from the initial mean, showing a peak of 13.6 x 106 cells µL-1 at 60 days old. The mean values for packed cell volume (PCV) and hemoglobin (Hgb) concentration increased (P < 0.05) until 90 days and decreased at 120 days (36.6% to 33.7% and 11.4 g dL-1 to 10.6 g dL-1 between 90 and 120 days, respectively). The means for mean corpuscular volume (MCV) and for mean corpuscular hemoglobin concentration (MCHC) increased (P < 0.05) between 30 and 120 days (27.5 µm3 to 29.7 µm3 and 26.6% to 31.4%, respectively). The total white blood cell (WBC) count increased (P < 0.05) and reached a peak at 90 days (9,314 cells µL-1). The peaks for segmented neutrophils (5,141 cells µL-1) and lymphocyte counts (4,236 cells µL-1) occurred at 60 and 90 days, respectively. The means for neutrophil/lymphocyte ratio were similar (P > 0.05) between the ages (mean of 1.8) but higher than the reference value for adult sheep (0.5). The initial mean for eosinophil counts (2 cells µL-1) was lower (P < 0.05) than all subsequent ones, and the monocyte count showed the lowest level (P < 0.05) at 120 days (232 cells µL-1). The mean for TPP at 60 days (6.4 g dL-1) was higher (P < 0.05) than the other ages. Except for band neutrophil and basophil counts, and fibrinogen concentration, the hematological parameters and the TPP of female lambs are influenced by age until four months of life and differ from the reference intervals established for adult sheep. Therefore, the interpretation of CBCs performed in female lambs should be made on the basis of age group-specific reference intervals.

Background: Neospora caninum and Toxoplasma gondii are closely related cyst-forming apicomplexan parasites identified as important causes of reproductive failure in cattle. Moreover, abortion cases attributed to N. caninum and T. gondii infection have been occasionally reported in sheep. Due to the relatively scarce information on the molecular detection of N. caninum in the semen of naturally infected rams, this study aimed to detect parasitic DNA in fresh semen samples and in frozen extended semen straws from male sheep from artificial inseminations centers in Southern Brazil.Materials, Methods & Results: Semen samples of 38 rams from artificial insemination centers were evaluated. Eleven rams were naturally infected (seropositive for anti-N. caninum and/or anti-T. gondii IgG) and were selected for fresh semen collection. We tested all the samples for the closely related protozoan T. gondii to detect a possible cross-reaction and co-infection, due to the close similarity with N. caninum. The indirect fluorescent antibody test was used to detect IgG antibodies in the 11 serum samples from rams. Fresh semen samples were collected from 11 rams on days 1, 50, 55, and 58 using an artificial vagina and ewe in estrus. Other 27 rams had their frozen extended semen straws analyzed. A total of 20 fresh semen samples and 27 frozen extended semen straws samples were used to detect the presence of N. caninum and T. gondii DNA by polymerase chain reaction (PCR). Nc-5 and B1 genes were used as target regions to detect N. caninum and T. gondii DNA, respectively. The presence of N. caninum DNA was confirmed in the third collection of a fresh semen sample of one seropositive ram. T. gondii DNA was detected in a fresh semen sample of one seropositive ram. The DNA sequences of 186 bp from N. caninum (GenBank accession: MH806393) and 492 bp from T. gondii (GenBank accession: MH793503) were obtained by sequencing, and analysis revealed 99% and 100% identity, respectively, compared with other sequences deposited at GenBank. N. caninum and T. gondii DNAs were not detected in any of the 27 frozen extended semen straws used for artificial insemination.Discussion: This study demonstrated the presence of N. caninum and T. gondii DNA in fresh semen samples of naturally infected rams. The non-detection of N. caninum and T. gondii DNA in frozen semen samples of rams could be due to the dilution that was used to prepare the semen straws (GGL diluent and 5% glycerol), since fresh semen samples were not diluted prior to the test. Moreover, in our study, the volume of frozen semen samples (0.25 mL) used for PCR was lower than the volume of sediment obtained from fresh semen (0.5 mL), and the fresh semen centrifugation to obtain the sediment may have grouped the tachyzoites, increasing the sensitivity of the technique employed. No high IgG serological titers were detected in the rams at the time they were eliminating the parasite through fresh semen. The final titer of anti-N. caninum and anti-T. gondii IgGs in serum was 1:100, suggesting chronic infection. It is suggested that a new parasite elimination pathway is occurring among rams used for reproduction, due to the presence of N. caninum and T. gondii DNA in fresh semen samples from seropositive animals. Although the detection of genomic DNA of N. caninum and T. gondii in semen does not necessarily imply the presence of infectious stages of the parasites and does not determine their viability, these results demonstrate the need for further studies. Our study also indicates the need to reinforce preventive measures for sheep in artificial insemination centers until the risks are evaluated, by performing serological examinations with anti-N. caninum and anti-T. gondii antibodies, for instance, to select the rams that will be used for breeding.

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Brazil has the highest number of birds of prey in the world, which are important environmental quality indicators. Nevertheless, few studies of the clinical pathology of raptors have been developed in this country. The objectives of this study were to create a database of owl hematology in Brazil and to compare the values between sex in Asio clamator, Megascops spp. and Tyto furcata. Blood samples were collected from 81 captive owls of 10 species located in Rio Grande do Sul, Santa Catarina, Paraná and São Paulo states, Brazil. Hemogram and Total Plasma Protein (TPP) values were determined. Reference intervals (RIs) and descriptive statistic values were established using an Excel program with Reference Value Advisor. The reference intervals were the following: A. clamator: RBC (×106/?L) 1.0-2.5; PCV (%) 30.2-50.1; Hb (g dL-1) 6.7-15.3; MCV (fL) 123.8-355.2; MCHC (%) 17.1-38.6; WBC (× 103/?L) 1.2-23.6; Heterophils (× 103/?L) 0.6-16.6; Lymphocytes (× 103/?L) 0.6-10.2; Eosinophils (× 103/?L) 0.0-1.9; Basophils (× 103/?L) 0.0-1.0; Thrombocytes (× 103/?L) 10.8-56.6; H/L 0.0-10.8. Megascops spp.: RBC (× 106/?L) 0.8-2.3; PCV (%) 29.7-44.6; Hb (g dL-1) 6.4-12.4; MCV (fL) 131.6-374.4; MCHC (%) 12.1-34; WBC (× 103/?L) 0.7-23.1; Heterophils (× 103/?L) 1.1-10.3; Lymphocytes (× 103/?L) 0.0-11.5; Eosinophils (× 103/?L) 0.0-2.2; Basophils (× 103/?L) 0.0-0.7; Thrombocytes (× 103/?L) 10.3-43.6; H/L 0.5-7.3; TPP (g dL-1) 2.9-5.1. The parameters for Tyto furcata were presented with descriptive statistics values. Individual data were provided for the others Strigiformes species sampled. This study provides a wide database of hematological and TPP references for Megascops spp., A. clamator and T. furcata and hematological values for Athene cunicularia, Bubo virginianus, Pulsatrix perspicillata, Asio stygius, Pulsatrix koeniswaldiana, Strix virgata and Asio flammeus in Brazil.