الفهرس 
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Abstract
Since the frozen dressed fish and shellfish are subjected to the risk of contamination with various pathogens from different sources, primary during their presence in their aquatic environments and secondary after being harvested for preparation, dressing (skinning, sticking, gutting and removal of fins) as well as preservation for marketing. Seventy five samples of frozen dressed Solea, Tilapia nilotica and
Squid (2 X 2 5 from each) were taken from different supermarkets and examined for sticking and tail regions organoleptically, bacteriologically and mycologically. The organoleptic examination for thel’samples revealed that all samples could be considered sound except three samples of Solea and two samples of both Tilapia nilotica and Squid. The bacteriological examination revealed that the total colony
counts from the sticking and tail regions of frozen dressed Solea, Tilapia nilotica and Squid in an overall log-mean were 8.206 ± 7.535, 8.044± 7.413and 7.631± 7.025respectively. It was found that the total colony count of sticking region (logmean
8.246 ± 7.423)was higher than that of tail region (log-mean 7.520 ±6.960). Accordingly, there was a significant differences between the types
and regions but the interaction between them was non significant. The total psychrotropllic count of sticking region (log. mean 8.016±7.199) was higher than tJ.- of tail region (log. mean 7.314 ± 6.759). It was found that the total psychrotrophic counts from sticking and tail regions of Solea, Tilapia nilotica and Squid in an overall log-mean were 7.948 ± 7.299, 7.854 ± 7.218 and 7.422 ± 6.784 respectively, with
highly significant differences between the types and between regions but the interaction between them appeared non significant. The total Enterobacteriaceae counts in an overall log. mean were 5.659 ± 4.699, 5.595 ± 4.673 and 5.490 ± 4.606 for Solea, Tilapia nilotica and Squid respectively, from sticking and tail regions.
Differences between the types and between regions were significant but the interaction between them appeared non significant. The total coliform counts of the examined samples were lower in tail region (log. mean 5.061 ± 4.146) than that in sticking region (log. mean 5.418 ± 4.352). Also the total coliform count of Solea (log.mean 5.364 ± 4.446) was higher than that of Tilapia nilotica (log.mean
5.272± 4.400)and Squid (log.mean 5.169± 4.322). The total Staphylococcus aureus counts from the sticking and tail regions of Solea, Tilapia nilotica and Squid in an overall log.mean were 6.012 ± 5.130/ 5.961 ± 5.114 and 5.758 ± 5.000 respectively. Count from sticking region (log. mean 6.084 ± 5.044) was higher than that in
tail region (log. mean 5.666 ± 4.845). Thus/ significant differences appeared between the types and between regions but the interaction between them appeared nOll significant. The total Enterococci count in an overall log.mean regardless the
types of fish and the regions of sampling was 3.944 ± 2.756/ with only high significant differences between the regions of sampling, while the differences between the ~ of fish and interaction between types and regions appeared non significant. Bacteria belonging to the following genera could be isolated from the sticking and tail regions of Solea, Tilapia nilotica and Squid in different percentages; Escherichia, Salmonella, Enterobacter, Shigella, Klebsiella, Citrobacter, Proteus, Serratia, Pseudomonas, Flavobacterium, Alcaligenes, Achromobacter, Chromobacterium, Acintobacter, Aeromonas, Staphylococcus aureus, Staphylococcus
epidermidis and Micrococcus. The mycological examination revealed that the total mould and yeast counts from the sticking and tail regions of Solea, Tilapia nilotica
and Squid in an overall log. mean were 2.968± 1.845and 2.833± 1.699
respectively, with regardless the type of fish and the region of
sampling. Differences between the regions of sampling appeared highly
significant, but the differences between the types of fish and interaction
between types and regions were non significant. Moulds and yeasts belonging to the following genera could be isolated in different percentages from the sticking and tail regions of Solea, Tilapia nilotica and Squid; Aspergillus, Penicillium,
Cladosporium, Thamnidium, Pusapum, Mucor, Trichoderma, Alternaria for mould and Candida, Torulopsis, Saccharomyces and Rhodotorula for yeast. The presence of large numbers of total colony count, total Enterobacteriaceae count, total coliform count, total Staphylococcus aureus count as well as total Enterococci count in the examined samples indicates that the fiIh loaded with these microorganisms from the polluted water and after catching during unsanitary handling, sticking, skinning, evisceration or improper refrigeration. Such frozen dressed fish may at times induce a public health hazard. Importance of isolated microorganisms as well as suggested hygienic measures to improve the quality of the frozen dressed fish had been discussed.