First isolation and molecular phylogenetic analysis of Coxiella burnetii in lactating cows

Abstract

Q fever is an infectious disease of animals and humans, caused by globally distributed C. burnetii. In Iraq, there are no previous studies associated with the detection of the organism in cattle. An overall of 130 lactating cows were submitted to direct collection of milk samples. Initially, the samples of milk were tested using the molecular polymerase chain reaction (PCR) assay targeting three genes (16S rRNA, IS1111a transposase, and htpB). However, positive results (18.46%; 24/130) were detected only with the 16s rRNA gene. Concerning risk factors, the highest prevalence of C. burnetii was showed in the district of Badra (42.86%), whereas the lowest - in Al-Numaniyah and Al-Suwaira districts (P=0.025). There was no significant variation in positivity between the months of sampling period (P=0.082) and between age groups (P=0.076). Crossbred cows (20.69%) showed a higher positivity than local and pure breeds (P=0.043). Milk of positive samples (n=24) was used for cultivation of C. burnetii into specific pathogen free-embryonated chicken eggs (SPF-ECEs). After three passages into SPF-ECEs, contents of yolk sac were collected, subjected for DNA extraction, and re-tested by PCR assay using the primer of 16s rRNA gene only. Of 24 cultivated milk samples, 12.5% (3/24) were positive for C. burnetii. Finally, the positive local isolates were analysed phylogenetically and reported in NCBI-Genbank under the accession numbers of MN121700.1, MN121701.1, and MN121702.1. In conclusion, this is a unique study as it detected C. burnetii in Iraqi lactating cows, and confirmed that organism was shed actively through milk, suggesting that these animals can play a role as a reservoir for organism with potential risk for transmission of infection from these animals to humans as well as to other animal species.

Characterization of a Polymorphism in the Stimulatory Region of the TNF Gene in Type 2 Diabetic Patients in Iraq

“…Our data were analyzed using of ANOVA test in GraphPad Prism (6.0.1) Software at a significant differences of P 0.05 [13,14].…”

Phytochemical investigation of some active constituents from N-Butanol fraction of Tropaeolum majus L. cultivated in Iraq

“…Subsequent injections and collections, the chemicals were separated in sufficient amount and purity to provide high-quality spectra. All data were analysed statistically as described previously (16,17).…”

A molecular analysis of Escherichia coli O157:H7 strains isolated from cow and buffalo milk by the use of PCR in Karbala province

“…Milk is a healthy and fulfilling nourishment for newborn mammals and humans, but it is also an excellent substrate for a variety of microorganisms (Leedom, 2006;Gharban and Yousif, 2021). E. coli O157H7 has the ability to survive for days or even weeks in milk and dairy products (Dineen et al, 1998(Dineen et al, , 1998Hudson et al, 1997).…”