The correlation coefficient (R2) for Jos (cultured, Clarias anguillaris was 0.8367 while the coefficient of b was 3.1046. The correlation coefficient (R2) for Jos (wild) showed 0.7785 while the coefficient b was 3.4779. The correlation coefficient (R2) for Yola (wild) revealed 0.8637 and the coefficient of b was 2.4785. The results showed that there was correlation of length and weight in all the samples though Jos (cultured and wild) had positive allometric growth while Yola (wild) had negative allometric growth

Danwesh, L.S.

Onyia, L.U.

Sogbesan, O.A.

Aquatic Commons

136
MATEI~IALSAND METHODS
Field methods: A total of ninety C.
anguillatis specimens were collected from
INTRODUCTION
Every animal grows in both length and
weight and the relationship between them is of
both theoretical and practical importance.
Comparison of the relationship indicates
changes in body shape or condition or the
animal.
The relationship between length and weight
has been referred by Haimovici and Velasco
(2000) and Costa Araajo (2003) as very
important key which was widely used in fish
biology with several purposes. This useful
tool provides important information
concerning the structure and function of fish
population. Moreover; it was used to predict
weights from length measured in yield
assessment (Ecoutin andAlbaret, 2003).
Laglcr( 1952) observed that the b
value can be affected by certain factor such as
increase in weight due to intake of water, food
or gonads and season of the year that fish is
captured. Ayuba (1997) reported that length
-weight relationship of Synodontis species in
River Renue Yol a showed a linear
relationship. Length-weight relationship can
be affected by several factors. Teasucr (1976)
observed that, gillnets can select the fatter of
short fish and thinner of long fish and thereby
affecting the l e n g t h v w c i g h t
rclationship.Sturrru 1978) also observed that
the difference in length-weight relationship
may occur as a result of gear selectivity, sex
*Onyia, L.U. Sogbesan, O.A.and Danwesh, L.S.
Department of Fisheries, Federal University Technology, Yola,
Adamawa State, Nigeria.
*Correspondence author: E-mail: uchelucky2005@yahoo.com
Tel: 08058047800.
ABSTRACT
The correlation coefficient (R2) for Jos (cultured) Clarias anguillaris was 0.~n67 while the
coefficient orb was 3.1046. The correlation coefficient (R2) for los (wild) showed 0.7785 while
the coefficient b was 3.4779. The correlation coefficient (R2) forYola (wild) revealed 0.8637 and
the coefficient of b v'as 2.4785. The results showed that there was correlation of length and
weight in all the samples though Jos (cultured and wild) had positive allometric growth while
Vola (wild) had negative allometric growth.
Keywords: Length-weight relationship, condition factor, wild and cultured Clarias anguillaris,
Nigeria.
LENGTH-WEIGHT RELATIONSHIPAND CONDITION FACTOR OF
CLARIASANGUILLARISFROM THE WILOAND CULTURED IN N[GERIA
and difference in season and time of the year.
The weight-length fish was usually
estimated by using the equation w=alb, where
a is the intercept and b is the algometry
coefficient after logarithmic transformation
of this relation(log 10= log a +log L)
parameters a and b were determined via least-
square Iinear regression collected are
validated by their analysis of the graph
corresponding to length-weight(Andrade and
Campos,2002; Ecouhu and Albaret,2003).ln
order to check if the value of b was
significantly different from 3, the student's t-
test gives information on the kind of growth of
fish.
The objectives of this study arc to compare the
length-weight relationship and condition
factors of Clarias anguillaris strains from the
wild and cultured inYola and Jos Nigeria.
The coefficient of condition factor is a
convenient way of comparing the relative
wellbeing of fish populations. The larger the
coefficient of condition factor, the heavier the
fish for a given length. Laglcr (1952) stated
that the value of condition factor ofa fish can
be influcnced by sex di ffcrcncc, age. changes
in season, gonad maturity levels, stomach
fulness and length and weight ofthe fish.
1 "'7_~I
DISCUSSION
The regression analysis from C.
anguillaris (Jos cultured) showed isometric
and positive allometric growth since the b
value was greater than 3. C. anguillaris (los
wild), also showed isometric and positive
allometric growth. Ayuba (1997) also found
the same length-weight relationship in
Synodontis spp in Upper River Benue Vola.
The b value for Yola wild was less than 3,
showing negative allometric growth. This
agrees with the work of Kolher et. al. (2007)
on Brycianns imberr; Pollimyrus isidori just
to mention a few species out of 57 species that
have negative allometric growth.
Olurin and Aderibigbe (2006)
reported that regression coefficients obtained
from length-weight relationships which are
indicative of isometric or allometric growths
differ not only between stocks of the same
species. There may also be differences in the
relationships due to sex, maturity, season and
environmental conditions. Moreover, Lagler
(1952) observed that the b value can be
affected by certain factors such as increase in
weight due to intake of water, food or gonads,
season of the year and the time of the day
when the fish was caught.
The correlation regression analysis
(r2) between weight and length of C.
anguillaris from Jos cultured, Jos wild and
Yola wild were significantly. high because
they were closer to I.This showed that the
strains from different genetic strains were in
good condition(Olurin andAderibigb~,2006).
It can therefore be concluded that C.
anguillaris in this study were in good
condition and healthy and can be used for
commercial production. The length-weight
relationship graph showed a lin e a r
Condition factor: The condition for the
species from the three different genetic groups
is shown in Table 1.The mean values are equal
or above one.
is expressed by the equation: Log w=
1.3919 + 2.4785 log I (figure 3).
The regression coefficients from the three
strains were 0.8367(1os culture), 0.8637(Jos
wild) and O.77R5(Yola wild).
RESULTS
(i) Length-weight relationship (Jos
cu lt u red): The length-weight
relationship is expressed by the
equation: Log w= 1.979 -r 3.1 046 log
I(figure I).
(ii) Length-weight relationship (Jos
wild): The length-weight relationship
is expressed by the equation: Log W""
O.95G~'" 3.4 779 log I (figure 2).
(iii) Length-weight relationship (Yola
wild): The length-weight relationship
Condition factor: The condition factor (k)
was calculated from the relationship;
K=IOOw/lb
Where:
w=weight (g)
I=Total Length (ern)
b= Regression co-cfficnt (Tudorancea, 1988)·
Vola {30), Jos culture (30) and Jos wild (30).
The specimens were transported to the
laboratory in black 251itreplastic jerry cans.
Laboratory analysis: The specimens were
mopped on filter paper to remove excess
water from their body surfaces. Their total and
standard lengths were then measured using a
ruler to the nearest one-tenth of the
centimeter. The total length was measured as
the distance from the snout to the tip of the
caudal fin while the standard length was
measured as the distance from the snout to the
caudal peduncle.
The body weight was taken on a top
loadingMetler balance to the nearest O.lg.
Length-weight relationship A scatter plot of
log body weight against log. Total length was
made for the species. The regression of weight
against length was computed from the
relationship: w=alb
Where:w= Weight (g), 1=Totallength (em), a
=Constant,
a=Exponent of values between 2 and 5.
The log transformation data gave a regression
equation:
Logw = log a +b log I
Where;
a= constant and
b= the regression co-efficient.
138
1.4
l.a
1.2
Mean value
Condition factor.
Yolowild
Jos wild
Jos cultured
Table 1: Condition factor (i1. anguillaristhree genetic strains::.___ _ __
Genetic strains
Relatively undistributed estuary. The
Gambia Fish Resources Vo1.72:347-
351.
Haimovici, M. and Velasco (2000). Length-
weight Relationship of Marine Fishes
from Southern Brazil. NAGA
ICLARMquartcrly, Vol.23 (1):14-16.
Kolher,N., Casey 1.and Turner, P.(1995).
Length-weight relationship for 13
Species from the Western North
Atlantic. Fish Bulletin (93 ):413-418.
Lagler,K.E.( 1952). Freshwater Fishes
Biology. Second Edition Lowa,
W.M.C. Brown, U.S.A.
Olurin,K.B. and Aderihigbe,O.A.(2006).
Length-weight Relationship and
Condition Factor of pond reared
Juvenile Oreochromis niloticus.World
Journal of Zoology 1(2)82-85.
Treasuer., T.W.(1976). The Age, Growth and
length-weight relationship of Brown
trout Salmon trotter in the Lake of
Strathberg.A Berbeanshire Journal of
Fish Biology (8):24 1.
REFERENCES
Andrade, H. A. and Campos, R.O.(2002).
Allometric Coefficient Variation of
The length-weight relationship of
Skipjack tuna (Katsuwonus pelanis)
Caught in the South-west Atlantic.
Fresh Resources vo1.55pp307- 1312.
Ayuba, Y( 1997). The food and feeding Habit
of Synodontis spp in River Benue
Vola, Nigeria. B. Tech. thesis,
Department of Biological Sciences,
Federal University of Technology,
Yola. 122pp.
Costa Araajo,F.G .(2003). Length-weight
Relation and Condition factor of
Micropogamia furnieri (perciformes
Sciaenidae) in the Scpetiba bay,
Rhode Jaweiro State Brazil Vol. 20
No.4 pp209-213.
Ecoutin, J .M. and Albaret,J.J .(2005). Length-
weight for fish population of
relationship, which is as the fish increases in
length, the weight of the fish also an increase.
139 .
log. l (em)
Figure 1. length-weight relationship of
wild Clarios anguiloris from Yolo
1.5 20.5 1
o .i,
o
..--------_._----I
2.:] /' I
'6)
~1.5 t Log (y) = 1.3919 + 2.4785Ln(x) I
~ R2 = 0.7785
1 -
I
0.5 ~
o 0.5 1 1.5 2
Log. L (em)
Agure 1. Length-weight relationship of _j
wild Clarias anguilaris from Yola
+-------+-----~
2.53 I
~ 2 i!1.5 Log (y) = 1.3919 + 2.4785Ln(x)~ 1 R2 = 0.7785
o.~ J
oL.---,---
log.l (em)
Figure 1. length-weight relationship of
wild Clarlas angullaris from Yolo
1 21.50.5
Log (y) = 1.3919 + 2.4785Ln(x)
R2 = 0.7785
3T
a2:1
~151
o:f
o 1-----+---- -----t------i
o


Length-weight relationship and condition factor of Clarias anguillaris from the wild and cultured in Nigeria

http://aquaticcommons.org/23306/2/026_opt.pdf

Length-weight relationship and condition factor of Clarias anguillaris from the wild and cultured in Nigeria

Abstract

Similar works

Full text

Available Versions

Aquatic Commons