HYGIENIC EVALUATION OF SOME FISHES MARKETED IN DAMIETTA

Abstract

A total of 200 random swab and muscle samples (100 each) were taken from whole marketable Tilapia nilotica and Clarias lazera (50 each) purchased at Damietta city, were examined physically and bacteriologically. The mean values of physical examination m examined Tilapia

nilotica and Clarias lazera were 80.8 ± 1.27 and 83.5 ± 1.16, respectively.

The mean values of total bacteria; Staphylococcus aureus, and

Coliform counts in examined Tilapia nilotica and Clarias lazera were

4.6x105 ± 2.04x105 and 6.8x105±2.53xl05; 7.3x102 ± 1.4 x 102 and l.07xl03 ± 0.16 x 103; and 79.7 ± 51.6 and 88.3±48.3 organisms/cm' of surfaces, respectively meanwhile these numbers were 3 .9x 105 ± 1. 78 x l 05 and 5.8xl05±2.24x105; 5.2xl02±1.lx102 and 7xl02±1.2xl02; and 50.1±30.3 and 61±31.6 bacteria/g. of examined muscles, respectively.

Escherichia coli, Klebsiella pneumoniae, Klebsiella aerogenes, Klebsiella oxytoca, Enterobacter cloacae, Enterobacter aerogenes, Enterobacter sakazaki, Citrobacter freundii, Proteus mirabilis, Proteus vulgaris, Proteus rettgeri, Proteus morganii, and Providencia spp. were isolated form all examined samples (surfaces and muscles of both fish) with percentages ranged from 4 to 44%. The economic and public health importance of isolated organisms as well as the suggested measures for improving the quality of fish were discussed.