000			03188cam a2200313 a 4500
003			EG-GiCUC
008			161127s2016 ua dh f m 000 0 eng d
040			_aEG-GiCUC _beng _cEG-GiCUC
041	0		_aeng
049			_aDeposite
097			_aM.Sc
099			_aCai01.10.09.M.Sc.2016.No.M
100	0		_aNoha Mohamed Bakry Nady
245	1	0	_aMolecular biological studies on Escherichia coli isolated from diarrheic and apparently healthy calves / _cNoha Mohamed Bakry Nady ; Supervised Walid Sayed Ahmed Abdelkader Awad , Amr Abdelaziz Abdelkader Elsayed
246	1	5	_aدراسات بيوجزيئية عن الايشيريشيا كولاى العزولة من عجول مصابة بالاسهال و عجول سليمة ظاهريا
260			_aCairo : _bNoha Mohamed Bakry Nady , _c2016
300			_a116 P. : _bcharts , facsimiles ; _c25cm
502			_aThesis (M.Sc.) - Cairo University - Faculty of Veterinary Medicine - Department of Internal Medicine and Infectious Diseases
520			_aNeonatal calf diarrhea is one of the most important problems in young calves causing great economic losses. In the current study, a total number of 150 fecal samples from diarrheic and apparently healthy in-contact cattle and buffalo calves under 3 months old were examined bacteriologically for isolation of E. coli. All isolates were confirmed by PCR using 16SrRNA gene. Multiplex PCR was applied for detection of virulence genes and for studying the association of these genes with different E. coli pathotypes. One hundred and six of 150 isolates were positive for at least one virulence gene. The rate of f , st, lt, eae, stx , stx , hylA and astA genes were 17.3%, 27.3%, 6.7%, 10%, 37.3%, 5 1 2 17.7%, 9.3% and 20.7%, respectively. Distribution of E. coli pathotypes revealed presence of ETEC, EPEC, STEC, EAEC, ET.EP. and ET.ST. at a rate of 12.7%, 2.7%, 30.7%, 7.3%, 2.7% and 14.7%, respectively. The rate of pathogenic E. coli infection in calves was higher in winter season and in the first weeks of life. Molecular serogrouping of E. coli isolates was carried using 10 O serogroups and revealed presence of O91 serogroup in the highest rate (62.7%), with higher rate of O26, O91, O121 and O45 in diarrheic calves. Comparing between molecular serogrouping and agglutination test revealed the ability of multiplex PCR to detect all isolates which were positive by agglutination and also 8 negative isolates. Five intestinal samples from four dead calves grossly showing congestion and distention of intestinal loops were bacteriologicaly positive for E. coli with higher rate of eae gene. Histopathological examination revealed heamorrhagic enteritis, shortening and fusion of intestinal villi, desquamation of lining epithelium of intestinal mucosa with congestion of blood capillaries and intense leucocytic infiltration
530			_aIssued also as CD
653		4	_aCalves
653		4	_aDiarrhea
653		4	_aMultiplex PCR
700	0		_aAmr Abdelaziz Abdelkader Elsayed , _eSupervisor
700	0		_aWalid Sayed Ahmed Abdelkader Awad , _eSupervisor
905			_aNazla _eRevisor
905			_aSoheir _eCataloger
942			_2ddc _cTH
999			_c58798 _d58798