الفهرس 
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Abstract
Introduction The present study is an approach to detect the role of insects as flesh flies in transmission of trichinosis infection from carnivorous animals to another hosts specially herbivorous animals (as sheep, caws, horses and ostrich) and to man, and to establish a fast precised and accurate method as Real-time PCR for detecting the presence of the infection at low level in any tissue in the hosts.
Material & methods
Infected pig diaphragm muscles were prepared for inducing infection in other hosts. Infection was proved by using trichinoscope and Real-time PCR. A total of 34 rats, were kept in optimum conditions, sacrificed (35 days p.i.) and identified for presence of Trichinella spiralis, then rats were divided into 4 groups: (A), (B), (C) and (D). Group (A), 18 rats feed on infected pig muscles and were sub-divided into 3 groups; Group (A-1), 4 infected rats slaughtered 8 dpi, their intestines were investigated for collection of adult T. spiralis worms, identified by Real-time PCR and considered as the positive control. Group (A-2), 4 infected rats slaughtered 35 dpi, their muscles were investigated microscopically for presence of infection and identified also by Real-time PCR. Group (A-3), 10 infected rats kept as a source of the infection, slaughtered when needed. Group (B), 2 un-infected rats be infected, slaughtered 35 dpi, their muscles used for Induction of infection in Sarcophaga 3rd instar larvae. Group (C), 10 un-infected rats fed on infected Sarcophaga maggots and slaughtered 35 dpi, their muscles were tested for presence of the infection by trichinoscope, and then identified also by Real-time PCR. Group-D, 4 un-infected rats slaughtered, their skeletal muscles, considered as the negative control and examined microscopically then identified also by Real-time PCR. Flesh fly colony of Sarcophaga argyrostoma prepared for proving their role in infection transmission among different hosts. Then, a group of maggots of different stages (2nd and 3rd larval instars) were fed on infected meat, until pupation. It was found that the fly 3rd instar larvae were having modified powerful mouth parts for grinding muscles enabled them for eating the infected rats’ muscles. Infected pig, rat, and Sarcophaga 3rd larval instars samples were prepared for identification by Real-time PCR. 2 pieces from each sample (infected pig and rat muscles, adult Trichinella larvae and Sarcophaga larvae) were homogenized and Real-time PCR reactions were performed. Results Microscopic examinations of diaphragm muscles of the infected pig revealed moderate level of Trichinella infections. Examinations of infected rats’ muscles revealed presence of encysted larvae, 35 days post infection and rate of infection was high and reached to 280-390 larvae/gm of meat. Examining of the alimentary canals of the infected rats group (A-1) revealed presence of free Trichinella adult worms. Examining of group (A-2) revealed presence of Trichinella cysts in their muscles. Examinations of the infected skeletal muscles of rats of (Group-C) revealed presence of infection but less heavy than that of the infected pig diaphragm muscles and infected rat skeletal muscles Pig origin infection). The mean of counted larvae ranged from 6-12 muscle larvae/gm. Examination of fly maggots (3rd larval instars) revealed that they had 6-8 free alive Trichinella larvae in their gut. Results extracted from Real-time PCR device revealed that the diluted of all hosts samples showed some differences due to the potency of infection. The diluted sample of the uninfected rats had no CT values. It was found that pigs and rats were good sources of transmission of trichinosis infection to other hosts, and flesh flies had an important role in transmission of trichinosis infection from carnivorous animals to herbivorous animals and to man. Using trichinoscopy and digestion methods were not accurate, but using Real-time PCR technique was very accurate, precised and confirmable for detection of trichinosis in any tissue of the host although in very low level of infection.