Histological and ultrastructural alterations in mullet fries exposed to industrial effluents

Histological and ultrastructural alterations in mullet fries
exposed to industrial effluents
O.M. Wahbi, N.M. Abou-Shabana, M.A. Essa and M.I. Zaki
Aquaculture Divission,National Institute of Oceanography and Fisheries, Alexandria, Egypt.
[email protected]
Received 24th September 2009, Accepted 11th November 2009
Abstract
Sugar Beet manufacturing company waste (El Dakahlia Governorate) caused mass mortality in the wild
mullet fries (Mugil cephalus and Mugil capito) collected from El-Kasarah Marine Fish Fry Center, during
the period of late autumn (15/12/2008) till late winter (17/3/2009). Water samples collected near source of
waste emission up to 750 m away revealed high levels of trace metals (Pb, Fe, Cd, Cu and Zn) which, were
reflected on their bioconcentrations in fry organs. Effect of metal waste on mullet fries were investigated
using histological and ultrastructure examinations. The results revealed degenerative changes in vital body
organs (gills, liver, kidney and gonads) .The respiratory epithelia of gills appeared reduced and vacuolated
with breakdown of pillar cell system and hyperplasia of chloride cells. Ultrastructure observations revealed
vacuolation, necrosis of cytoplasmic organelles and vesiculation and proliferation of the endoplasmic
reticulum in mullet fry liver.. Also the waste exert inhibitory effects on gonadogenesis.At late winter
(17/3/2009) the quality of water improved but, still the waste exerts an effect on fish organs causing mass
mortality especially during catch and transportation to fish farms.