Sheep abortions associated with Neospora caninum and Toxoplasma gondii infections in multiple flocks from Southern Brazil

• Published in: Veterinary research communications Vol. 48; no. 4; pp. 2699 - 2705
• Main Authors: Withoeft, Jéssica Aline, Marian, Lucas, da Costa, Leonardo Silva, Fernandes, Fagner D’ambroso, Vogel, Fernanda Silveira Flores, das Neves, Gabriela Bassi, Miletti, Luiz Cláudio, Casagrande, Renata Assis
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.08.2024; Springer Nature B.V
• Subjects: Abortion; Abortion, Veterinary - epidemiology; Abortion, Veterinary - parasitology; Animals; Arthrogryposis; Biomedical and Life Sciences; Brazil - epidemiology; Brief Report; Coccidiosis - epidemiology; Coccidiosis - parasitology; Coccidiosis - veterinary; Encephalitis; Female; Fetuses; Genetic markers; Genotypes; Genotyping; Gliosis; Heart diseases; Life Sciences; Myocarditis; Myositis; Neospora - genetics; Neospora - isolation & purification; Neospora caninum; Neosporosis; Pestivirus; Polymerase chain reaction; Pregnancy; Protozoa; Restriction fragment length polymorphism; Sheep; Sheep Diseases - epidemiology; Sheep Diseases - parasitology; Sheep Diseases - virology; Tissue culture; Toxoplasma - genetics; Toxoplasma - isolation & purification; Toxoplasma gondii; Toxoplasmosis; Toxoplasmosis, Animal - epidemiology; Toxoplasmosis, Animal - parasitology; Veterinary Medicine/Veterinary Science; Zoology; Brazil; Protozoan; Sheep; Apicomplexa; Reproductive loss; Lambing; Abortion
• ISSN: 0165-7380; 1573-7446; 1573-7446
• DOI: 10.1007/s11259-024-10390-4

Neosporosis and toxoplasmosis are important parasitic causes of abortions in small ruminants. This study verified the occurrence of these diseases in sheep fetuses from Santa Catarina State, Southern Brazil from 2015 to 2022. Sheep fetuses were necropsied with organ sampling for histopathology, and polymerase chain reaction (PCR) for Neospora caninum and Toxoplasma gondii using the Nc5 and SAG2 targets, respectively, in frozen brain tissue. Microbiological culture and RT-PCR for Pestivirus were conducted to discard other abortion causes. One positive fetus for toxoplasmosis was genotyped using multiplex multilocus nested PCR-RFLP (Mn-PCR-RFLP) with ten genetic markers. Fifty-five sheep fetuses were evaluated, with 10 (18.2%) cases of neosporosis and 7 (12.7%) cases of toxoplasmosis, comprising six and four flocks, respectively. Macroscopically, neosporosis abortions exhibited fetal mummification, maceration, and arthrogryposis. Toxoplasmosis abortions showed fetal mummification and maceration. The neosporosis abortions included lymphoplasmacytic myositis (70%; 7/10) and myocarditis (60%; 6/10), in addition to necrotizing encephalitis and gliosis (50%; 5/10). Toxoplasmosis abortions included lymphoplasmacytic necrotizing encephalitis (71.4%; 5/7), lymphoplasmacytic myositis (42.8%, 3/7), and myocarditis (14.3%; 1/7). Through PCR, N. caninum and T. gondii were detected in 6 (60%) and 5 (71.4%) fetuses, respectively. In one fetus, T. gondii genotyping was conducted, which was characterized as atypical genotype ToxoDB #98. All of the cases were negative for Pestivirus and bacterial agents. This study establishes the occurrence of these diseases as causes of abortions, malformations, mummification, and fetal maceration in sheep, with the characterization of an atypical T. gondii genotype in one of the fetuses.