Effect of El-Sail Drain Wastewater on Nile Tilapia (Oreochromis niloticus)from River Nile at Aswan, Egypt

Abstract

This study demonstrates the impact of wastewater of El-Sail Drain on the health of Oreochromis niloticus collected from two sites of River Nile at Aswan Governorate. One of these sites is before (I) and the other is after (II) the disposal point of El-Sail drain. The physicochemical parameters of water (pH, electric conductivity, total dissolved solids, dissolved oxygen, biological and chemical oxygen demands, nitrite, nitrate and ammonia) were determined. Heavy metals (Cu, Pb, Cd and Ni) concentrations in water and fish tissues (gills, muscles, liver and gonads) were detected. The microbiological, parasitological and pathological conditions of fish were also investigated. Higher values of pH, EC, BOD and COD were detected in site II than from site I. In contrast to DO, nitrite, nitrate and ammonia which were lower in site II. Heavy metals concentrations in water of both sites, especially Ni, Pb and Cd exceeded the permissible limits and its abundance followed the order: Pb>Ni>Cd>Cu. Total bacterial count, total coliform, Salmonella sp., Shigella sp. and E. coli were detected in higher numbers in water samples from site II. Moreover, the fish caught from that site revealed higher bacterial and parasitic infection. The bioaccumulation of Ni and Pb exceeded the maximum permissible limit; however, Cu and Cd concentrations were below the permissible limit in different tissues. The bioaccumulation factor of Cu showed its highest value in liver. The histopathological lesions were more prominent in fish collected from site II. So, consuming fish caught from the studied sites around El-sail drain disposal point represents serious hazard on human health.

Bacterial Quality and Molecular Detection of Food Poisoning Virulence Genes Isolated from Nasser Lake Fish, Aswan, Egypt

“…The variance in the initial bacterial load of the examined fish samples can be attributed to the microbial load of the water in which they reside and the proliferation of bacteria that thrive under storing conditions [ 17 ]. Fishes are affected by the bacterial load and the bacterial species that are present in the ecosystem; also, Ali et al [ 34 ] showed that fishes collected from polluted sites (drainage) recorded higher bacterial loads (in different fish organs) than fishes collected from nonpolluted sites. The results supported Amuneke et al [ 35 ] and Khairy et al [ 36 ].…”

Histopathological Studies on Tilapia zillii Fish in Relation to Parasitic Infestations at Lake Temsah

“…Most of fish parasites are causing little or no harm to their hosts under the natural environmental conditions (Ali et al 2015). In the same time, internal parasites are considered the first reason in the most fish diseases, causing low body gain, high mortality, immarketability and some of these diseases may have zoonotic importance.…”