OCCURRENCE AND DISTRIBUTION OF SARCOCYSTIS PARASITE ISOLATED FROM SHEEP IN YAZD PROVINCE, IRAN
Introduction: Sarcocystis species are one of the most important meat borne parasites. Sarcocystosis causes several symptoms in human as well as numerous diseases with a high economic impact on livestock. In the current paper at first the results of a pilot study for determination of disease agent in the lambs of Yazd province in central Iran is presented. Then the status of parasite in red meat products in the study region is discussed. Materials and Methods: Muscles of 70 slaughtered sheep from both sexes and different ages were investigated for presence of parasite cysts from September to October 2013. Carcass inspection with naked eye at industrial slaughterhouses of Yazd for macroscopic cysts, and pepsin-digestion method for microscopic cysts was performed on common infected sites
MICROSCOPICAL AND SEROLOGICAL STUDIES WITH ULTRASTRUCTURE DESCRIPTION OF SARCOCYSTIS SPECIES IN SHEEP IN ASSIUT
This study was conducted to determine the infection rate of Sarcocystis species in sheep in Assiut. A total of 100 slaughtered sheep examined for Sarcocystis, no macroscopic cysts were observed, 93% (93/100) were positive by microscopical examination and 28% (28/100) were positive by using Agar gel diffusion test. The infection rate of Sarcocystis had very high significant differences between microscopic examination and Agar gel diffusion test. High statistical significant effect was found on the infection rate of Sarcocystis in different examined muscles of sheep. The highest infection rate was recorded in oesophagus (71%), followed by diaphragm (65%), tongue (58%), skeletal muscles (53 % ) and heart muscles (43 % ). The infection rate of Sarcocystis in males was 95.2% (40/42) while in females were 91.4% (53/58) by microscopical examination. Higher infection rate of Sarcocystis were detected in sheep 6 months - 2 years age 95% (38/40) than that of sheep between 2-4 years old 92.7% (38/41) and those equal or older than 4 years 89.5% (17/19). No significant difference between infection and age groups or sex of animals was observed. The use of transmission electron microscope (TEM) allowed the identification of S. tenella and S. arieticanis in sheep in Assiut. Examination of S. tenella cyst wall with TEM showed palisade-like villar protrusions while, examination of S. arieticanis cyst wall showed hair-like villar protrusions parallel to cyst wall.
Coexistence of Virulence and Antibiotic Resistance Genes in Pasteurella multocida Isolated from Diseased Rabbits
Pasteurella multocida (P. multocida)is considered a predominant pathogenic bacterial agent causing respiratory manifestations (snuffles) in rabbits with considerable economic losses and unfavorable prognosis in Egypt. A few recent P. multocida strains exhibit resistance to the most commonly used antibiotics in the veterinary field. Therefore, the present study was carried out to investigate the prevalence of both virulence and antibiotic resistance genes among P. multocida isolated from diseased rabbits in Sharkia Governorate, Egypt. Only 10 out of 100 tested rabbits` nasal swabs were finally confirmed positive for P. multocida of serogroup A by polymerase chain reaction (PCR). Antibiotic susceptibility testing of the recovered isolates revealed that they were all multidrug resistant (MDR) with a predominance of resistance to amoxicillin, ampicillin, amoxicillin/clavulanic acid, neomycin and tetracycline (100% each), followed by kanamycin and streptomycin (90% each). All the recovered isolates were further subjected to PCR screening of some common virulence and antibiotic resistance genes of interest . With the exception of toxA gene, the other virulence associated genes (ptfA, Omp87 and nanB) were found among all the examined isolates. Totally, all MDR P. multocida isolates contained at least one antibiotic resistance gene with aphA1 being the most prevalent (100%), followed by ermX gene (40%). Antibiotic resistance genotyping demonstrated the presence of multiple antibiotic resistance genes among majority of the isolates (40%) with only one isolate harboring 4 genes encoding identical resistance phenotypes. Evidentially, all MDR P. multocida isolates possessed at least 3 virulence genes accompanied by the attendance of antibiotic resistance genes. These findings evidenced that rabbits are potential sources of pathogenic P. multocida strains harboring virulence and antibiotic resistance genes. Therefore, it is evident that there is an urgent need for the judicious use of antibiotics in rabbits` treatment systems to successfully mitigate the propagation of drug resistance across P. multocida species.