Abstract
Background:
Numerous infectious agents and risk factors cause diseases of the respiratory system in farm animals. Parainfluenza virus type 3 is a common cause of respiratory tract infections in cattle, sheep, and goats worldwide.

Aim:
The goal of this study was to investigate the clinical and molecular identification, as well as phylogenetic tree analysis of Caprine para influenza virus 3 (CPIV3) in goats in various regions of Al-Najaf, Iraq.

Methods:
During December 2022 and November 2023, 100 nasal swabs showing signs of pneumonia were obtained from two separate goat fields belonging to the College of Veterinary Medicine, University of Kufa. The quantitative findings were presented as a chi-square test (χ2) was performed to assess the significance of the observed variances. A total of 100 nasal swabs were collected from goats, with CPIV3 possessing a molecular incidence of 38%. The clinical manifestations included fever, cough, difficulty breathing (rapid, short breaths), decreased appetite, and weight loss. There are no significant differences between the three areas of AL-Najaf province and sex (p > 0.05).

Results:
Infection rates were significantly higher in age groups older than 1 year. A phylogenetic study of the (M) gene in Caprine parainfluenza virus 3 revealed that the local Iraqi isolate accession numbers (OR978482.1–OR978486.1) were found to be closely related to NCBI-BLAST Caprine parainfluenza virus 3 strain JS2013 (KJ850331.1) at a total genetic alteration (0.01%).

Conclusion:
CPIV-3 is a serious respiratory infection that affects goats all over the world, including Iraq. Clinical manifestations of CPIV-3 infection range from mild respiratory problems to severe pneumonia, causing significant economic losses in the goat industry.

Key words: Caprine parainfluenza virus 3; Molecular detection; PCR; Al-Najaf; Iraq.