Dr. Abdul Latif Korai

Department of Fresh Water Biology and Fisheries, University of Sindh, Jamshoro

HISTOLOGICAL STUDIES OF LIVER OF MAJOR CARPS FROM KEENJHAR

LAKE.

Histology is an important field of fish health that can often detect subtle conditions or early signs of disease not easily recognized on gross examination.

Changes in the cellular level in the function of key organs are the first indications of mal adjustment to stressors that may eventually lead to poor health or disease.

A histological investigation related to uptake of heavy metal pollution on the tissues of exposed fish could provide valuable information, and for predicting human health risks.

An established and comprehensive database of fish histology could become an integral part of environmental impact assessments and could assist in decision making process as well as recommendations regarding to fish.

Importance of Histology

Aims and Objectives Histological analysis appears to be a

very sensitive parameter and is crucial in determining cellular changes that may occur in target organs such as liver to reflecting the health of an entire aquatic ecosystem.

Short and long term exposure periods may significantly influence the histological damage and alterations caused by exposure to heavy metals.

Heavy metals (HMs) pollution is of great concern and its has harm full effects on aquatic animals, to investigate the uptake of HMs contamination in an ambient medium of aquatic ecosystem and hepatocytic anomalies.

Fish samples were collected at the three sampling sites from Keenjhar Lake, in live and moribund conditions at the fish landing centers.

Liver samples were fixed in Bouins’s fixative for 30 hours. Than the tissues were decalcified to remove brittleness caused from acidity of fixative for 14 hours.

Tissues were kept under the runining tap water for 2 hours, after that the tissues were dehydrated from following series of bath’s.

The dehydrating and staining of tissue were carried out through standard procedure.

Material and Methods

Fish species Lead Cadmi

um Nicke

l Zinc

C. catla H.0.881±0.00

3

0.851±0.009

0.91±0.0095

0.884±0.00

95

L. rohita H.0.867±0.00

9

0.835±0.0085

0.946±0.0067

0.922±0.00

76

C. mrigala H.

0.697±0.00

7

0.881±0.0078

0.802±0.0078

0.841±0.00

85

Labeo rohita H.

Tumor, reduction of hepatocytes, hepatic cell alignment was

disrupted, hyperemia (L. S. H&E stain)

Labeo rohita H.

Cirrhosis and hepatocytes with pyknotic nucleus (L. S. H&E stain)

Labeo rohita H.

Hepatocytes with pyknotic nucleus, hepatic cell alignment

was disrupted and hyperemia (L. S. H&E stain)

Cirrhinus mrigala H.

Disruption of hepatic parenchyma, hepatocytes with pyknotic nucleus, tumor and necrosis (L. S. H&E stain)

Cirrhinus mrigala H.

Disruption of hepatic parenchyma, hyperemia, hemorrhage and

cirrhosis (L. S. H&E stain)

Cirrhinus mrigala H.

Tumor, hepatic cell alignment was disrupted, hepatocyte vacuolation, aneurysm and hyperemia (L. S. H&E

stain)

Catla catla H.

Disruption of hepatic parenchyma, hemorrhage,

cirrhosis and aneurysm (L. S. H&E stain)

Catla catla H.

Disruption of hepatic parenchyma, cirrhosis, swelling of hepatocytes and

aneurysm (L. S. H&E stain)

Catla catla H.

Cirrhosis, hepatic cell alignment was disrupted and hyperemia (L. S.

H&E stain)

Fish species Keenjhar Lake

Cirrihinus mrigala (Hamilton)

TumorReduction of hepatocytesDisrupted hepatic alignmentNecrosisLeukocytes infiltrationHyperemia CirrhosisAneurismHepatocytes vaculationHepatocytes with pyknotic nucleus Hemorrhage

Labeo rohita (Hamilton)

Reduction of hepatocytesDisrupted hepatic alignmentNecrosisLeukocytes infiltrationCirrhosisAneurismHepatocytes vaculationHepatocytes with pyknotic nucleus Hyperemia

Catla catla (Hamilton)

Reduction of hepatocytesTumorDisrupted hepatic alignmentHyperemiaHepatocytes vaculationCirrhosisCytolysisHepatocytes with pyknotic nucleus Aneurysm

ConclusionL. rohita, C. mrigala and C. catla H. were selected for histological examination due to their popularity as food fish relished throughout Asia. Usually, these species are cultured in ponds and dhands (small standing water bodies), owing to fast growth-rate and high economical value. It is concluded that the histological distortion increases with the increase in toxic influx. Lake Keenjhar has a low content of waterborne toxicants; however, histological anomalies do occur, if measures are not implemented to minimize the exposure to high levels of toxicants, Lake Keenjhar will become dystrophic, and the local population will face socio-economic disaster. Among the fish species examined in the present study, C. mrigala H. has the greatest number of histological anomalies in the liver. C. mrigala H.

Measures must be taken to minimize the content of waterborne toxicants, to prevent or minimize the deleterious effects of toxicants on aquatic organisms and consequent adverse effects on consumers, especially those living in the vicinity of Lake Keenjhar. It will be important to monitor the metals burden in sediments and associated biota of Lake Keenjhar.

Thanks