Egwu, O.E.

English

Aquatic Commons

ACUTE TOXCFY OF WATER EXTRACTS OP BARK
OF THE NEEM PLANT, AZADIRACHTA INDICA (LODD)
TO THE AFRICAN RIVER PIKE HEPSETUS ODOE
(SARCODACES) 000€ (BLOCH)
BY Oti Emmanuel Egwu
college of Natural Resources and Environmental Management
Michael Okpara University ofAgriculture
Umudile, 1M.B. 7267, UMUAHIA, ABIA STATE, NIGERIA
ABSTRACT
he effects of the water extract of bark of the Neern plant (Azadirachia indica on the mortality rate.
I opercular ventilation rate, and some behavioural respionses of 11. odoe were investigated under
laboratory conditions over a 96 h exposure period. The 96 h LC5O waqs determined as 8MOmg L—l. The
extract led to an initial increase in the opercular ventilation rates which then decreased significantly
(P<0.05). Prior to death, darkening of fish, erratic swimming, and respiratory distress were observed. The
implication of those findings in relation to environmental pollution is discussed.
Key words: Hepsetus odoe,Azadirachta indica, acute toxicity. extract.
INTRODUCTION
Aquatic pollution problems are due to the addition
of deoxygenating substance, eroded sediments and
chemical contaminants, urban Sewage, agriculture,
wastes from industrial activities, radionuclides,
salinization and acidification of soils, heated
effluents from power plants. Recent assessments
by the UNEP/WHO Global Environmental
Monitoring System (GEMS) have identified the
main water pollutants including sewage nutrients
and toxic; metals as well as agricultural chemicals
(UNEP. 1991). The most common water pollutants
is organic material from domestic sewage,
municipal waste, and agro-industrial effluent:
(Lean et al. 1990).
Discharge of urban sewage and industrial and agro
industrial waste waters rich in organic matter, such
as effluents derived from pulp and paper
production, palm oil extraction and sugar-beet
processing containing high levels of decomposable
organic substance; can lead to reduction of the
oxygen content of recipient waters and create
arioxic conditions in poorly mixed waters. The
release of human and animal organic wastes carries
the risk of high microbial loading which may lead to
bacterial and viral infections (Barg eta! 1996).
Water quality is deteriorating in key basin from
urban agricultural and industrial wastes (WR
1990). Hazadous, sometimes toxic, trace elements
arc accidentally or deliberately dumped into water
bodies. Pesticides and herbicides in drainage water
and agricultural runoff from field are becoming a
widespread source of aquatic pollution, and
enclosed water bodies such as lakes, reservoirs,
small water bodies and ponds are particularly at
risk, Fish species and other aquatic biota which are
top predators in the food chain may accumulate
high levels of toxic compounds; in their bodies
tissues which may well present a health hazard to
humans if consumed in sufficient quality (Calamari
andNaeve 1994).
Over the last years in many African countries the
use of plant extract to catch fish has been on the
increase. This has entailed a great increase in
22
discharge of pollutants to receiving waters causing
undesirable effects on the aquatic environment and
on fisheries.
The introduction of pollutants into the aquatic
environment set in motion several disruptions to
aquatic productivity which, according to Warren
(1977), will eventually lead to some physiological
dysfunetions in aquatic organisms. The use of
plant extract for the control of aquatic molluscs
responsible for the transmission of water borne
diseases has been documented (Osuala; 1989) Oh
and Ukpabi (2000). Though there are advantages
in the use of plant extracts in the control of aquatic
snail vectors, the issue of pollution of the aquatic
environment by such extracts, particularly their
effects on fish, has been highlighted by Ufodike
audi omoregie (1994). Medina and Woodbury
(1979) screened members of the families
Solanaceae, Fabiaceae, Rubiacene, and
Eupliorbiacear for rnolluscicidae activity and
found them to be potent on most snail vectors and
other aquatic organisms. Ade-Serrano (1982)
observed that the leaves, fruits, seeds, roots, and
bark of the Neem plant. Azadirachta indica (Lodd)
MATERIAL AND METHOD
Fingerlings of H. odoe (mean weight 6.010.i0 g)
of the same broodstock collected from Cross River
in Nigeria were used for the investigation. The fish
were acclimatized for 10 days in 20-litre glass
aquaria, during which time they were fed twice
daily at th.e ratwe of 4% of their body weight. Each
aquarium was supplied with dechlorinated, well-
aerated municipal tap water, which was changed
daily. Mortality during the acclimation period was
less than 2%. Thereafter the fish were stocked at 10
fish per aquarium for the experimental runs. Two
aquaria acting as replications for each treatment
(concentrations) were setup.
The bark of A. Indica was removed and dried at
23
contain eriterperenoid, azatin, sosiarin:, and other
active components with properties that are
repellent and growth disruptive to living
organisms. Ornoregie and Okpanachi (1992), Oti
and Ukpabi (2000) reckported growth retardation
in Tilapia zilli (Gervais) and Heteroclaria
exposed to sublethal concentrations of A. indica,
and bark of Thevetia Peruviana respectively.
Extracts of plants have been observed by Reed et
al, (1969) to be used by fishermen in the tropics
for fishing. Crude extracts are broadcast over the
water surface, poisoning the fish which are then
picked by hand from the water.
H. Odoe is a common member of the African
tropical freshwater ichthyolfauna, where it is well
suited as fish food (Anthony 1982), hence its
choice for this investigation. Owing to the
possible contamination of the tropical freshwater
system with extracts of toxic plants and the death
of information on their toxicity to tropical
freshwater fish, the aim of the study was to
evaluate the acute toixicity of water extracts of
the bark of A. indica (popular known as Dogon-
yareo in Nigeria) to the African River Pike,
60°C for 5 days. The well-dried samples were
pounded in a clean mortar and sieved using a
0.1mm sieve. The fine particulate was dissolved
in distilled water for 24 h at room temperature.
(22.5°C). The settled aqueous portion was then
decanted and centrifuged for 10 mm at 1,500 rpm
to remove particulate matter. The clear solution
was filtered through a Whatman filter paper (No.
1) using a vacuum pump. The filtered solution
was freeze-dried for 24 h. A stock solution of
100mg U1 of the freeze-dried materials was made
from which the following concentrations were
prepared and introduced into each of the
experimental aquaria along with their replication:
50,25, 12.5, arid 3.125mg U. The water in each
of the test aquaria was changed daily during which
period fresh concentrations of the bark extract were
introduced.
Methods for acute toxicity tests as described by
Sprague (1973) were employed. The estimation of
96 h LC5O for the extract was determined by probit
analysis using the arithmetical method. Mortality
was recorded every 24 h though the aquaria were
inspected every 3 h for dead fish, which were
removed immediately. The opercular ventilation
rate per minute was read at the start and every 24 h
thereafter. During the exposure period the
temperature. dissooved oxygen, free carbon
dioxide, and p1-I in each aquarium were monitored
every 4 h using methods described by API-IA
(1980). The temperature, dissolved oxygen, free
carbon dioxide and p1-I of the experimental aquaria
At the higher concentrations, the colour of the
exposed fish became darker, respiratory distress
and erratic swimming being observed before death
occurred. At lower concentrations (6.25 mgL and
less), such changes were minimal; the control
group of fish showed no such signs.
The opercular ventilation rate of the exposed fish
initially increased sharply, the increase being
were observed to be maintained at the following
ranges: 24.22-24.76°C, 7.27-7.40 rng U, 2.39-2.52
mg U1 and 6.48-6.55, respectively. The results
obtained were subjected to statistical analysis with
the application of Duncans multiple range P-test
for significant differences (P<0.05) between the
various treatments.
RESULTS
Percentage, mortality decreased significantly
(P<0.05) with decreasing concentrations of the
extract (Table 1). No mortality was recorded in the
control, group throughout the exposure period.
The 96 h LC5O value was observed to be 8.00 mgU
with lower and upper limits of 5.00 and 7.00 mgL
respectively. The computed regression equation
wasfoundtobey=5.5O+ i.70x(r"'0.900).
directly proportional (P<0.05) to the extract
concentration (Table II). The opercular ventilation
then decreased steadily until the 72 h of exposure.
However, by the 96 h of exposure, the ventilation
increased significantly (P<0.05) in the group of fish
exposed to 12.5, 6.25 and 3.125 MgL. The
changes in the opereular ventilation rate of the
control group of fish throughout the experiment
were statistically non-significant.
24
Thble 1: Mortality rate of Hcpsetus odoe (Blocli) exposed to various acute concentrations of water
extracts of the bark of Azadirachta indica (Lodd) results of two replications
Concentration(rngI2')
50.0
- Number of fish dead at Range of mortaIy(%)
241i 48h 72h 96h -
6 9 17 18 80-100
15.0 4 8 9 17 7090
12.5 4 5 6 15 60-80
6.25 2 5 10 40-60
3.125 1 4 3 10-30
Control 0
Table II: Opercular ventilation (mean of six readings ± SE) rates per minute of Hepsetus odoe
(Bloch) exposed to various acute concentration of Azadirachfa Indica (Lodd)
Concentration(mgL Start 24 h
150±2.50 122±0.20
Time
48 h 72 h j 96 h
0.O 108±0.70 109±1.30 100±1'.20
25.0 143±1.70 119±0.20 102±0.20 98±0.90 100±1.02
12.5 130±0.92 90±1.30 90±1.30 98±1.10 105±0.90
6.25
3J25
100±0.50
90±0.37
102±0.50
92±0.10
90*1.70
90±0.82
98±0.80
92d1.i0
102±1.19
102±1.20
Control 87*0.25 86±0.60 851.13 82±1.10 821.42
DISCUSSION
The results obtained from this study shows that
concentrations of water extracts of the bark of A.
Indica led to increased mortality of H. odoe. The
value of 96 h LC5O of 8.00 mgL reported in this
work is much higher than those earlier reported by
ufodike and Omoregie (1994). Oti and Ukpabi
(2000) when they exposed the Nile tilapia
Oreochromis niloticus (Trewavas) to water extracts
of the bark of Balanites Aegyptiaca (Lodd) and
Kigelia africana (Lodd). This shows that the bark
extract of A. Indica is less toxic than those of B.
Aegyptiaea and K. Africana, hence higher
concentrations of A. Jndica would be required to
elicit 50% mortality of fish than the latter extracts.
Osuala (1 9X9) had earlier reported thata extracts of
bark of A. Indica contain properties that are
inhibitory to the normal metabolic processes of
fish. Omoregie and Okpanachi (1992) reported
retardation in the growth of T. zilli when exposed to
sublethal concentrations of water extracts of bark
of A. Indica. The increased mortality reported in
the present investigation was due to the impairment
of normal metabolisni by the inhibitory
components in the extracts. The darkening of the
fish, respiratory distress, the initial
hyperventilation, and erratic swimming observed
in this study are indications that mortality of the
exposed fish is not due to impaired metabolism but
could in addition be due to nervous disorder. These
abnormal behavioural responses in fish exposedk
to toxicants were earlier reported by Dc silva and
Ranashiughe, (1989) Ufhdike and Omoregie
(1990, 1994) and Okwusa and Omoregie (1995). It
has been reported by many investigators that the
dark colour of fish is due tos the dispersion of
melanin pigments in the chromatophores which
move towards the periphery, by pituitary hormone
intermedin or M.S.H Novales (1959) reported that
melanindispersion by M.S.H. requires the presence
of Na ions in the medium. He also stated that
among the substances which afafect pigment
movements in chromatophores, melanocyte
stimulating hormone (MSH) has been most
important. The extract also penetrate the non-scaly
region very rapidly.
The skin membrane of the boarder of the
operculurn and over the skin on the rim of the eye is
very thin. So any change in chromatophores will
be seen very clearly. Fuji (1961) among others
stated that melanophores are primarily controlled
by the autonomic nervous system and the nerves
which function are sympathetic. Distress and
decrease in fish activity (metabolic) is due to
depletion in energy substances like protein,
carbohydratcs and lipids during pollution. The
25
concentration of tile extract may have been due to
the increased utilization of the body substances
(Carbohydrates protein, and lipids) during stress
(Kabeer Ahrned et al, 1979). . Similar results are
also reported in fish by various authors. Umminger
(1970) is of the opinion thata carbohydrates
represents the principal and immediate energy
precursors of animals when exposed to stress
conditions. where protein being energy source of
spare during chronic condition of stress. Various
authors had similar reports on fish exposed to
toxicants (Oti and Ukpabi 2000, Jayacbandra and
Chockalingam 1986). Decrease in fish activity in
this present investigation indicates the utilization of
all three substances when the fish is under stress. If
the principal and immediate energy source gets
depleted, the other sources exhibit a proportional
depletion as the metabolism of these substances are
i.e tricarboxylic acid Cycle (TCA). Hence there is
a depletion in all the component of fish tissues
leading to stress,
The use of extracts of A. Indica and other similar
plants by local fishermen in rivers, stream and
lakes, coupled with their use in the control of
aquatic snail reservoirs vectors, is seriously ill
advised, as the resultant deleterious effects on fish
subjected to acute exposure will subsequently lead
to death. If the present rate at which these extracts
are being used in Africa is not checked, the
continuous existence of the aquatic fauna,
including biologically important fish species, will
be in serious jeopardy. The environment
authorities within the tropical region of the world,
need to set new quality standard on the use of these
plant extracts in the aquatic environment.
S-Serano 0. (1982) Growth inhibitory and lymphocytotoxic effect ofAzadrachta Indica. J.
Med. Plants, 5, 137 139.
Anthony, a. D. (1982) IdentificationofNigerianfreshwaterfishes. JosUniv. Press2lpp.
APHA (1980) Standards for examination water (15th edn). Washington, Americam, Public
Health Association, 1976 pp.
BARG, U. Dunn, I .G., T. Petter, and R.T. Welcome (1996) Inland Fisheries in Water
Resources, Ed. Asit K. Biswas, McGraw: Hill Publishers NewYork 667 pp.
Calamari and Naeve (1994) Review of Pollution in the African aquatic environment. FAO
Publication of tile United Nations, Rome 1994 ll8pp.
Dc Silva C.D. and Ranasinghe, J. (1989) Toxicity of four commonly used agro-chemicals on
Oreochromis niloticus (L) fry Asian Fish. Sci., 2. 135 145.
Fuji, R. (1961) Demonstration of advenergic nature of transmission of thejunction between
Elanophores concentration nerve and melanophores in bony fish. J. Fac. Scio. Univ.
ofTokyosect.9: 171 196.
Jayachandra K.P. S. and Chockalingam S. (1986) Effect of Tannery effluent on the
respiratory parameters and biochemical constituenth in air breathing fish Channa
punctatus. Comp. Physiol. Ecol. 12(4): 197 200.
KABEERA. Begun S. Sivajah S. (1979) Effects of malathion on free amino acids, total
Proteins and glycogens Proc. IndianAcad. Of Sci. 57: 337 381.
26
reduction in metabolic aactivity with increasing° inter-linked through a common metabolic pathway
REFERENCES
LEAN 0. D. Hinrichsen and A. Markham (1990) Atlas of the environment. Prentice-Hall
Englewood Cliffs N.J.
Medina. F. R. and Woodbury R.(1979) Terristrialpiants rnoliusciidal to lymnachi host of
Fasciola HEPATICAIN Puerto Rico. J. Agricult. Univ. Puerto Rico, 63 366-367.
NO VALES. R. R. (1 95( The effects of osmotic pressure and sodium concentrations on the
response of malanoiphores to intermedin pysiol. Zool. 32: 15 28.
Okwuosa, V. N. and Omoregie, E. (1995) Acute toxicity of alkyllenzeiie suiphonate (ABS)
Detergent to the ktoothed carp. APJ-IYOSEMION GAIRDNERI (L)Aquacult. Res.
26.755 758.
Omoregie, E. and Okpanachi. M. A. (1992) GrowthofTilapiazilli exposed to sublethal
Concentrations of crude extracts ofAzadirachta Indica. Acta Hydrobiol. 34,
281 286.
Osuala. F. O.U (1989) Survey of some plants for niollyuscididal activity around Jos
Metropolis. Ph.D thesis, University OfJos, 263 pp.
(Ytj, F, F. and U.FI. Ukpabi (2000) Acute toxicity of milk extract of Thevetiaperuviana to
African catfish (hybrid: Heteroclaarias)Afr. J. of Sci. and Tech. 1(1) 132 138.
Oti, F. E. (1999) Comparative studies on the impact of water quality on the growth survival
Of the African Catfish fingerling {h. D Thesis, Nmadi Azikiwe University Akwa
Nigeria i62pp.
Reed, W., Burchand J.. Hopson,A. L. Jennese. J. and Yaro L. (1969) Fish and fisheries of
Northern Nigeria. Zaria (Nigeria). Gaskiya Corp. Ltd. 156 pp.
Sprangue, J.B. (1973) The ABC of pollutant bioassay using fish. In: Cairus J. and Dickson
K.L. eds) Biological methods for the assessment of water quality. Philadepeiphia.
American Society for Teating and Materials 528, 6 30.
Ufodike, E.B.C. and Omoregie F. (1990) Acute toxicity ofGammalin 20 andActellic 25 EC
to Oreochromis niloticus. Acta Hydrobiol., 32.447 455.
Ufodike, E.B.C, and Omoregie B. (1994) Acute toxicity ofwater extracts of barks of
BALANITES AEGYYPTIACA and KIOELIAAFR1CANAto OREOCHRQMIS
NILOTICUS (L). Aqualcult. Fish Mgmt. 25, 878 g79
UNtP (United Nations Environment Programme) (1991) Freshwaterpollution
UNEP/QEMS Environmental Library No. 6 UEP, Nairobi, Kenya.
Uinminger,B.L. (1970) Physiological studiesonsupercooledhulifish. J. experimental
Zool.173: 159 174.
Warren C.E. (1977) Biologyk of water pollution control. Philadelphia. Saunders Co.,
434pp.
WRI (World Resources institute) (1990) Freshwater in World Resources 1990 1991 pp.
161 177, Oxford University Press.
27



Acute toxicity of water extracts of bark of the Neem plant, Azadirachta indica (Lodd) to the African river pike, Hepsetus odoe (Sarcodaces) Odoe (Bloch)

http://aquaticcommons.org/850/1/FISON2003_022-027.pdf

Acute toxicity of water extracts of bark of the Neem plant, Azadirachta indica (Lodd) to the African river pike, Hepsetus odoe (Sarcodaces) Odoe (Bloch)

Abstract

Similar works

Full text

Available Versions

Aquatic Commons