الوبائية والفحص الجزيئي لأنواع العطيفة في الانسان والدجاج اللاحم في محافظة كربلاء

Prevalence and Molecular Identification of Campylobacter in Human and Slaughtered Broiler in Kerbala Province

Abstract

A study was done during the period from December 2021 to July 2022 to determine the prevalence of Campylobacter species and their infection rates in humans and slaughtered broiler at Kerbala province. A total of 260 samples were collected as follows: 40 cecal swabs were collected from different local markets distributed in Kerbala, 80 samples from de-feathering machines and carcass rinse water, and 40 samples from local and imported frozen chickens, in addition to, 100 samples from people with diarrhea from Al-Hussain Medical City and General Children’s Hospital at Kerbala (Iraq). Samples were Inoculated immediately onto C&S modified Carry Blair transport media then Cultured on Campylobacter agar enriched with 5-10% blood and Incubated in anaerobic jar for 48 hrs. at 42°C under microaerophilic condition. Campylobacter spp. colony isolated on Campylobacter agar base selective media appeared as small, mucoid colonies, usually grayish in coloration and some have to be creamy grey in color, slightly raised, moist and often produce discrete colonies, flat with irregular edges, and non-hemolytic at 24-48 hours. Forty – four isolates out of 260 samples were confirmed to be Campylobacter species with positive oxidase, catalase and indoxyl. Eleven (two form human sample and nine from broiler sample) isolates (25%) from 44 suspected samples were subjected to molecular identification single PCR for confirmation of Campylobacter as genus. All examined isolates showed to be Campylobacter and were amplified 812 bp PCR products, while Five isolates (9%) from 44 suspected samples were subjected to multiplexed PCR for detection of three species of Campylobacter (C. jejuni, C. coli & C. lari.). Four of these samples show this genus were C. coli.
Results showed that Campylobacter spp. were detected in 38 (23.75%) of 160 samples. Out of the positive samples, the number of positive isolates detected from broiler intestine were 26 (68.42%), while the number of detected isolates from de-feathering machines were 4 (10.52%). However, the number of isolates from carcass rinse water were 5 (13.15%) and the lower rate was reported in frozen carcasses which was 3 (7.89%) positive. It turns out that there is a correlation between the bacteria and the site of infection, where the evidence showed a significant increase in the intestine when compared to De-feathering machines and carcass rinse water (p-value ≤0.01).

Out of 100 stool samples 6 (6%) yielded Campylobacter species on culture. For the category (2day-5years) samples, the detection rate was 20%, while 5% for (5-10 years), and 5% for (10-15 years) From the current study, this result shows that there is a significant (p-value ≤0.05) correlation between age and infection with Campylobacter spp., as the results showed high infections in children under five years of age, and the incidence rate decreases with increasing age.

The effect of temperature on the survival and growth of bacteria was studied, the results showed that the temperature of 4ᵒC, which is the degree of keeping food in the refrigerator, significantly affects the reduction of the number of bacteria and prevents the multiplication of its numbers. In addition, the results showed that the temperature of 20ᵒC (room temperature) promoted a significant increase in the number of bacteria. In addition to temperature, the effect of pH on bacteria was studied. Three degrees of pH were chosen to study the effect of changing the pH of carcass meat hours after slaughter on the survival and growth of bacteria, as it was found that low pH affects the activity of bacteria.