Molecular and histopathological identification of ovine neosporosis (Neospora caninum) in aborted ewes in Iraq

Abstract

<jats:p>Aim: The objective of the present study was to detect Neospora caninum DNA in the placenta of sheep and evaluate the association of risk factors to polymerase chain reaction (PCR) positive and histopathological analysis of the placenta and fetal tissue samples of aborted fetuses. Materials and Methods: Fresh placenta from 51 aborted ewes was collected for PCR assay. Placental and fetal tissues of aborted fetuses, including brain, heart, liver, lung, and thymus, were collected for histopathological analysis, besides the risk factor data were obtained during the time of sampling. Results: From 51 placentas examined by PCR, 13.73% appeared positive to N. caninum DNA. The relationship between PCR positive and the risk factors revealed a significant difference (p&lt;0.05) in age of the dam, fetal age, feed source, water source, and the presence of other animals at farm, whereas the type of birth, stillbirth, and size of flock showed insignificant difference (p&gt;0.05). Histopathological investigation of placental and fetal tissues of positive samples showed tissue cyst-like structure, necrotic foci, and infiltration of mononuclear cells. Other lesions were thickening in chorionic plate in placenta, severe vacuolization and death of neurons, microgliosis, demyelination, edema, and proliferation of astrocytes in brain. In addition, fibrous and fat deposition with stenosis in the heart, parenchymal necrosis, severe atrophy, vacuolization and hyalinization of hepatocytes, megakaryocyte, portal fibrosis in the liver, and interlobular septal thickening in lung without obvious lesions is seen in the thymus tissue samples. Conclusion: This is a unique study that confirmed N. caninum DNA in the placenta of aborted ewes in Iraq using PCR assay. Histopathological analysis of some aborted fetuses organs could provide a more confirmatory and reliable data for a significant role of neosporosis in increasing the rate of abortion in sheep, while the clinical data of risk factors could be used to control the transmission of N. caninum infection.</jats:p>

Molecular and histopathological detection of lumpy skin disease in Buffaloes, Iraq

“…For light microscopy, formalin fixed and paraffin-embedded procedure (FFPE) was used to prepare the tissue sections (Slaoui and Fiette, 2011;Al-Shaeli et al, 2020). After 24 hours of tissue fixation, the 10% of NBF was discarded and consciously replaced each 12 hours interval.…”

Congenital Transmission of Apicomplexan Parasites: A Review

“…The latter is the primary mechanism responsible for maintaining the parasite within livestock populations. The presence of the parasite induces an inflammatory response leading to placental damage and consequent abortion (Cantón et al, 2014b;Al-Shaeli et al, 2020).…”

“…Thus, multiple necrotic lesions, thickening of the chorionic plate, and mineralization of necrotic foci can be observed in the infected ovine placenta. Notably, both the oocysts (sexual state) and tachyzoites (rapidly dividing parasite stage) of N. caninum can be detected in placental tissue (Mesquita et al, 2018;Al-Shaeli et al, 2020;Figure 4A). In the fetus, N. caninum causes severe damage to the brain, heart, lung, and liver (Al-Shaeli et al, 2020).…”

“…Notably, both the oocysts (sexual state) and tachyzoites (rapidly dividing parasite stage) of N. caninum can be detected in placental tissue (Mesquita et al, 2018;Al-Shaeli et al, 2020;Figure 4A). In the fetus, N. caninum causes severe damage to the brain, heart, lung, and liver (Al-Shaeli et al, 2020).…”

Neospora caninum and Toxoplasma gondii as causes of reproductive losses in commercial sheep flocks from Argentina

“…Several reports have suggested the role of naturally acquired N. caninum infections in sheep, and its involvement in poor reproductive performance and abortions in flocks from different countries, i.e. Argentina ( Hecker et al, 2019 ), Brazil ( Moraes et al, 2011 ; Filho et al, 2017 ; Pereira et al, 2021 ), Iran ( Asadpour et al, 2013 ), Iraq ( Al-Shaeli et al, 2020 ), Italy ( Gazzonis et al., 2019 ), New Zealand ( West et al, 2006 ; Howe et al, 2012 ), Spain ( Moreno et al, 2012 ; González-Warleta et al, 2014 , 2018 ), Tunisia ( Amdouni et al, 2018 ), and UK ( Bartley et al., 2019 ). However, the role of N. caninum as a significant pathogen and abortifacient in flocks is yet under discussion.…”