Twenty nine E. coli isolates were previously isolated from beef from slaughter house, and raw milk of different origin were collected from different parts in Basrah. Five E. coli isolates were identified as E.coli O157:H7 using O157 and H7 antisera. E. coli O157:H7 isolates were tested for antimicrobial susceptibility test. The results showed that all tested bacteria were sensitive to gentamycin and Amikacin and resistant to amoxicillin and cefoxitim. The DNA of these isolates were amplified to detect verotoxins gene (vt1, 91bp) and pyelonephritis-associated pili gene ( pap,91bp). All the isolates were observed having (vt1) All the isolates were observed having (vt1) and pap genes.

Two isolates of Staphylococcus aureus and Pseudomonas aeroginosa of bacteria were exposed to different concentrations ( 5 , 10 or 25 mg /l )of heavy metals ions ( Silver Ag2+ , Cobalt Co2+ or Lead Pb2+) for different exposure periods ( 0 , 1, 2, 24 and 48 hrs.) .The results showed that the inhibitory effect of these metals on the growth of the two isolates were in the following sequences :- Pb < Co < Ag Some of these metals caused an elongation of lag phase in liquid medium for these isolates . Whene antibiotic discs ( chloramphenicol 30 mcg , clindamycin 2 mcg , erythromycin 15 mcg , gentamycin 10 mcg ,tetracyclin 30 mcg and vancomycin 30 mcg ) were added to solid medium which was previously supplemented with the above heavy metals ions , a synergestics effect was observed between antibiotics and heavy metals ions ( specially silver ions at 25 mg/ l )to increase the inhibition zone significantly ( P < 0.01 ) for both isolates .

Diarrhoea in calves is considering a serious clinical problem inBangladesh. Calf is the back bone of the dairy industry. Diarrhoea in farm animals, especially in neonatal calves is one of the most challenging clinical syndromes encountered by large animal Veterinarypractitioners. The present investigation was conducted with the aimed to evaluate the efficacy of ciprofloxacin and gentamycin in the treatment of diarrhoea in neonatal calves. The studied was carried out for a period of six month from January 2013 to June 2013 in Kanaighat, Sylhet, Bangladesh. Calves (n=60) under 10 days of age with clinical signs of diarrhoea were randomly divided into two groups. One group was treated with intramuscular ciprofloxacin at a dose of 5 mg/kg once daily, while other group was treated withintramuscular (IM) gentamycin (dose of 5 mg/kg) once daily for three consecutive days. Calves evaluated clinically from the treatment and the recovery rates for the ciprofloxacin and gentamycin groups afterthree days of treatment were 73.33% and 66.67%, respectively. This trial revealed ciprofloxacine administered through IM route from the first day of the clinical sign observed was more efficacious in calfdiarrhoea compared to gentamycin.