Prevalence of Neospora caninum as an etiologic agent of animal abortion in Kurdistan Region of Iraq.

Overview

• This study investigated the prevalence of Neospora caninum, a parasite causing abortion in livestock, in small ruminants and equines in the Kurdistan region of Iraq.
• The research also examined risk factors associated with infection and genetically confirmed the parasite strains found in the local animals.

Background

• Neospora caninum is a protozoan parasite known to cause neosporosis, which leads to serious reproductive problems like abortion in various animals such as cattle, sheep, goats, horses, wild animals, and dogs.
• Neosporosis is significant worldwide due to its impact on animal health and economic losses in livestock production.
• The study focuses on small ruminants (sheep, goats) and equines (horses, donkeys) in the Kurdistan region, an area where data on this parasite had been limited.

Study Design and Sample Collection

• Researchers collected tissue samples from aborted fetuses, including brain, placenta, heart, lung, and liver. A total of 64 tissue samples were taken.
• Blood samples were collected from 122 dams (mother animals) from local breeds: 63 sheep, 39 goats, 12 mares (female horses), and 8 jennies (female donkeys).
• This allowed for concurrent examination of both aborted fetuses and their mothers to assess the infection prevalence.

Prevalence Results

• The DNA of N. caninum was detected in the blood samples of:
  • 20.6% of sheep
  • 17.9% of goats
  • 21.4% of horses
  • 25.0% of donkeys
• In aborted fetal tissues, the prevalence was found to be:
  • 19.3% in sheep fetuses
  • 17.6% in goat fetuses
  • 18.1% in horse fetuses
  • 20.0% in donkey fetuses
• Overall, 20.3% of aborted dams tested positive for N. caninum, and 18.7% of their aborted fetuses were also positive.

Molecular and Phylogenetic Analysis

• Partial sequences of the Nc-5 gene from N. caninum isolates (accession numbers OP771519, OP771520, OP771521, OP771522) were analyzed.
• A phylogenetic tree was constructed to compare these sequences with known N. caninum strains in the GenBank database.
• The isolates showed 98-100% sequence identity, confirming the presence of N. caninum and supporting the molecular diagnosis.

Risk Factors

• Older animals, both small ruminants and equines, had a higher likelihood of being infected with N. caninum.
• Exposure to dogs was identified as a significant risk factor (p < 0.05), which is consistent with dogs being definitive hosts that shed oocysts in the environment.
• This suggests that infection control may require management of dog contact with livestock and proper hygiene to prevent spread.

Implications and Conclusions

• The study confirms that N. caninum is a notable cause of abortion in small ruminants and equines in the Kurdistan region.
• Understanding the prevalence and risk factors can help veterinary authorities and farmers develop targeted strategies to reduce infection and associated economic losses.
• Control measures could include better management of dogs on farms, monitoring of older animals, and molecular diagnostics to detect infections early.
• The findings add valuable epidemiological data from Iraq, contributing to global knowledge about neosporosis in diverse geographic regions and animal hosts.