ABSTRACT Sol (Channa marulius, family: Channidae, order: Perciformes) is an important fish species indigenous to Indo-Pakistan sub-continent, and has a commercial value, adapted to survive in low dissolved oxygen. Three populations (Indus, Indian and Thailand) appear isolated and significant difference between Indus and Indian population has appeared in mansural characters. Karyological studies on Channa marulius suggest a diploid number of 44 for the species but the Indian population and Thailand population are different in number of metacentric and telocentric chromosomes. Sol samples (n =7, 15-20 cm) were collected from Head Tounsa (river Indus) and their gill tissues were removed, torn apart and left in hypotonic solution, fixed and spread over a glass slide, stained with aceto-orcein and studied under microscope (100 X). Study of 45 well spread metaphase suggested a diploid number of 44, 8 metacentric having arm ratio of around 2 and 36 telocentric. Present population shares 2n number of 44 with the stocks of the species present in India and Thailand, yet is different from two other stocks in respect of chromosome morphology (Indian: 40 metacentric + 4 telocentric; Thailand: 4 metacentric + 4 submetacentric + 36 telocentric), suggesting intraspecific differences probably caused by isolation

A Mian

M Rafiq

M Z Bhatti

CiteSeerX

Bhatti et al J. Anim. Plant Sci. 23(2):2013
475
KAYROTYPE OF SOL (CHANNA MARULIUS) FROM INDUS RIVER, PAKISTAN
M. Z. Bhatti, M. Rafiq* and A. Mian**
Punjab Fisheries Department, Rawal Town, Islamabad, Pakistan; *Pakistan Natural History Museum, Islamabad,
Pakistan; **Bioresource Research Centre, 34, G6/4, Islamabad, Pakistan
Corresponding author e-Mail: bhattizfr@hotmail.com
ABSTRACT
Sol (Channa marulius, family: Channidae, order: Perciformes) is an important fish species indigenous to Indo-Pakistan
sub-continent, and has a commercial value, adapted to survive in low dissolved oxygen. Three populations (Indus, Indian
and Thailand) appear isolated and significant difference between Indus and Indian population has appeared in mansural
characters. Karyological studies on Channa marulius suggest a diploid number of 44 for the species but the Indian
population and Thailand population are different in number of metacentric and telocentric chromosomes. Sol samples (n
=7, 15-20 cm) were collected from Head Tounsa (river Indus) and their gill tissues were removed, torn apart and left in
hypotonic solution, fixed and spread over a glass slide, stained with aceto-orcein and studied under microscope (100 X).
Study of 45 well spread metaphase suggested a diploid number of 44, 8 metacentric having arm ratio of around 2 and 36
telocentric. Present population shares 2n number of 44 with the stocks of the species present in India and Thailand, yet is
different from two other stocks in respect of chromosome morphology (Indian: 40 metacentric + 4 telocentric; Thailand:
4 metacentric + 4 submetacentric + 36 telocentric), suggesting intraspecific differences probably caused by isolation.
INTRODUCTION
Fish karyotyping is commonly exploited to
confirm taxonomic identification and inter-population
variations and can play an important role in sex control,
better performance, rapid production of inbred lines
(Thorgard and Allen, 1987; Lin and Peter, 1991),
detecting environmental mutagens and genotoxic
pollutants (Kligerman et al., 1975; Manna, 1989). A
sizable literature on karyotype studies on Cyprinidae is
available from different parts of the world (Al-Sabti,
1985; Zhang and Reddy, 1990; Fister, 1989; Boro, 2001;
Khuda-Bukhsh and Tiwary1994; Khuda-Bukhsh, 1996;
Khuda-Bukhsh and Chakrabarti, 1996, 1999) including
Pakistan (Rab, 1981; Rafique, 1992; Rafique et al.,
2000).
(This paper is a part of Ph.D. thesis of principal author)
Indian snakehead or Sol (Channa marulius,
family: Channidae, order: Perciformes) is an important
fish species indigenous to Indo-Pakistan sub-continent,
and has a commercial value, better adapted in low
dissolved oxygen and is a potential fish for introduction
in the aquaculture system of Pakistan. The species is
distributed throughout the subcontinent from Thailand to
the river Indus. Different populations of the species are
isolated, yet no study is available about sub-specific
variations. Comparative studies on the mansural
(morphometric and meristic) characters are limited to
decide upon sub-specific variations, though there are
indications of the population surviving in the Indus river
is significantly different in some mansural (morphometric
and meristic) variables (Bhatti, 2012). Karyological
studies suggest that the species has a diploid number of
44, however different populations differ in the types of
chromosomes. Donsakul (1991) and Donsakul and
Wichian (1991) recorded that the stock of C. marulius
has 4 metacentric, 4 submetacentric and 36 telocentric
chromosomes for the Thailand stock, while the Indian
stock has 40 metacentric and 4 telocentric chromosomes.
Present study is based upon the hypothesis that stock of
Channa marulius inhabiting the Indus river has remained
isolated from the stocks surviving in river systems of
central and eastern parts of the Indian subcontinent.
Isolation may have caused variation in mansural variables
as well as in karyology. Present report pertains to the
results of studies on karyology of stock inhabiting the
Indus river.
MATERIALS AND METHODS
Preparation: Specimen of C. marulius (n =7, 15-20 cm
long), collected from the River Indus (in/ around Head
Tounsa, southwestern Punjab, Pakistan) identified to
species level (Mirza and Sandhu, 2007), brought to the
laboratory at Pakistan Museum of Natural History,
Islamabad in stress free conditions and maintained in
aquarium (30’ X 18’ X 12). These specimens were used
for karyological studies using the technique employed by
Oellermann and Skelton (1990) and Rafique (1992). Each
fish was caught from aquarium by a scoop net, weighed
using top loading balance (Sartorius, minimum count 0.1
g) and given 0.01 ml/ g body weight of 0.1% colchicines
(100 mg/ 100 ml distilled water) solution through
intramuscular route using 27 gauge syringe. Fish such
treated were maintained in a separate aquarium under
normal condition for 4–10 hours, when the gill arches
The Journal of Animal & Plant Sciences, 23(2): 2013, Page: 475-479
ISSN: 1018-7081
(This paper is a part of Ph.D. thesis of principal author)
Bhatti et al J. Anim. Plant Sci. 23(2):2013
476
were removed and gill tissue was torn in to minute pieces
physically using a needle. Gill tissue thus removed was
placed in 0.4% potassium chloride hypotonic solution for
40 minutes, allowing cells to swell up which result in
better spreading of the chromosomes (Manna, 1989).
Hypotonic solution was decanted and tissue rinsed in 25
ml of freshly prepared fixative (ethanol/methanol: glacial
acetic acid, 3 : 1) and left in fixative overnight for
complete fixation.
Glass slides were cleaned by boiling in detergent
for 20 minutes, rinsed thoroughly in running tap water,
passed through two changes of 90% ethanol, washed with
distilled water and oven dried at 50 oC. Clean and dry
slides were placed on a slide warmer adjusted at 60 oC.
Fixed tissue was dropped on a clean and dry glass slide,
allowed to dry, stained with aceto-orcein and covered
with clean and dry cover slip. Prepared slides were
examined under light microscope (Olympus BH-2, phase
contrast, 100X oil emersion lens) and good preparations
labeled and maintained for photography.
Cells having good metaphase spreads were
photographed using 35 mm camera fitted with automatic
film advance and exposure systems with built-in
microcomputer on light microscope. Negatives were
developed in pepitol developer for 2-3 minutes at 3,000
X. Photographs were then placed in fixative (250 g
sodium thiosulphate + 50 g potassium meta-bisulphide +
5 ml glacial acetic acid + I L distilled water) for 30
minutes. Photographs were thoroughly washed in tap
water to remove traces of developer/ fixative and dried on
a photographic drier.
Analysis: Diploid chromosome number was determined
by examining 45 photographs of well spread metaphases.
Maximum number of chromosomes inmajority of the
spreads was taken as diploid chromosome number of the
species.
Homologous chromosomes were arranged on
the basis of morphological similarity (size, position of
centromere and secondary constriction). Homologous
chromosome pairs were then arranged in decreasing order
of their sizes, and location of centromere to develop
karyotype for the species, and assigned number in
consecutive order, the largest metacentric regarded as
pair 1. Each chromosome of the karyotype was also
assigned a specific number in consecutive order of its
arrangement. Individual chromosome and homologous
pair were classified as metacentric, submetacentric or
telocentric, based upon the relative centromeric location.
RESULTS
Plate 1 presents microphotograph of the mitotic
chromosome spread of C. marulius collected from
Tounsa Barrage (river Indus). Count of chromosomes of
45 good spreads of chromosome suggested a modal 2n
number of 44, which could be organized into 22 pairs (n
= 22).
Karyotype developed for the present population
of the species (Fig. 1) suggests that 4 homologous pairs
(8chromosomes) are metacentric, with an arm ratio of
around 1, and 18 pairs (36 chromosomes) are acrocentric
chromosomes. The fundamental arm number for the
population under present analysis has been calculated as
52 (2 X # metacentric + # acrocentric chromosomes).
(a) (b)
Plate No. 1: Mitotic metaphase spreads of Channa marulius captured from Head Taunsa (southern Punjab,
Pakistan) a. without clearing, b. after clearing
Bhatti et al J. Anim. Plant Sci. 23(2):2013
477
Figure 1: Karyotype of Channa marulius captured from Head Taunsa (southern Punjab, Pakistan). (bold
numbers above denote the numbers assigned to homologous pair and small numbers below denote the
numbers assigned to individual chromosome).
DISCUSSION
Two previous studies available on the karyology
of C. marulius (Donsakul, 1991; Donsakul and Wichian,
1991; NBFGR, 1998) are in line with the present results
in suggesting that the species has a 2n number of 44
which indicates that the species over the range of its
distribution maintains a diploid number of 44 (n = 22).
On the other hand this also supports the taxonomic
identification of the stock of fish in this analysis as C.
marulius, as has been suggested by our previous
observations on general morphology along with
morphometric and meristic analyses revealing that the
sample exhibited a good degree of similarity in majority
of variables to justify its assignment to C. marulius
(Bhatti, 2012).
Present results on the types of chromosomes
present in the karyotype of this stock of C. marulius are
not in conformity to two previous studies available on
this species. Present analysis reveals 8 metacentric
chromosomes (arm ratio around 1) and 36 acrocentric
chromosomes (arm ratio around 0). This part of present
results is not in conformity on any previous study. No
study is available on the population of sol inhabiting on
river Indus waters. Studies on Thailand stocks suggests
predominance of telocentric chromosomes (36) with 4
submetacentric and 4 metacentric ones (Donsakul, 1991;
Donsakul and Wichian, 1991). Karyological studies on
the population of Indian species revealed 40 metacentric
and 4 telocentric chromosomes (NBFGR, 1998).
Population of C. marulius inhabiting the Indus river
seems therefore closer to its Thailand counterpart,
compared to Indian population. Intrapopulation
differences have also been indicated between the Indian
and Indus populations in different mansural characters
(Bhatti, 2012), which appears confirmed through the
karyological variation between populations. No study is
available on mansural variables of Thailand population
Bhatti et al J. Anim. Plant Sci. 23(2):2013
478
and hence possible level of morphometric / meristic
similarities with Indus population. A number of studies
are available on different species, where diploid
chromosome number remains same, yet the relative
number of different types of chromosomes is different for
different populations (Rishi, 1976; Tripathi and Sharma,
1987; Rafique, 1992). Though such discrepancies can be
ascribed to excessive chromosomal contraction as a
consequence of higher dose or over-exposure to
cholchicine, improper fixation of tissue, methods of
chromosomal preparation and classification (Zhang and
Ruddy, 1990), yet these variations may also arise from
chromosomal aberrations/rearrangements followed by
population isolation during evolutionary process. Chu
and Bender 1961; Campos and Cuevas 1997).
Channidae is one of the advanced families of
freshwater teleost fishes. This family originated in the
south Himalayan region of Indian subcontinent some 50
million years ago, during the early Eosine epoch (Bohme,
2004). This advancement of family is well reflected by its
karyotype to have all 40 metacentric chromosomes, as
against 4 telocentric chromosomes in Indian population,
considered to be most primitive (Morescalchi, 1975;
Campos and Cuevas, 1977). The presence of majority of
telocentric chromosomes in karyotype of Indus and
Thailand populations of C. marulius (Donsakul, 1991;
Donsakul and Wichian, 1991) is difficult to explain,
except that these populations may have secondarily
derived from more advanced populations present in
central parts of the Indian subcontinent, from where this
species may have originated.
REFERENCES
Al-Sabti, K. (1985). Karyotypes of Cyprinus carplo and
Leusicus caphalus. Cytobios., 47: 19-25.
Bhatti, M. Z. (2012). Some studies on the reproductive
biology of sol (Channa marulius) in the Punjab,
Pakistan., Ph.D. dissertation (unpublished)
Deptt. Zool., PMAS University of Arid
Agriculture Rawalpindi,
Böhme, M. (2004). Migration history of air-breathing
fishes reveals neogene atmospheric circulation
patterns. Geology, 32: 393–396.
Boro, A. (2001). Comparative chromosomal studies on
two minnow fish, Phoxinus phoxinus and
Eupallasella perenurus: an associated
cytogenetic- taxonomic considerations.
Genetica, 111: 387-395.
Campos, G. A. and C. Cuevas (1997). 1Karyotypes of the
most primitive catfishes (Teleostei:
Siluriformas: Diplomystidae) H, J. Zool.
System. Evol.Res., 35: 113–119.
Chu, E. H. Y. and M. A. Bender (1961) Chromosome
cytology and evolution in primates. SCIENCE,
133: 1,399-1,405.
Donsakul T. and M. Wichian (1991). Kan suksa
chromosome khong pla chon chon-ngu-hao
chado krasong lae pla kang thi phop nai prarthet
thai. In: Proc.29th Kasetsart Univ. Ann. Conf.:
Anim. Sci., Vet. Sci., Aquacul. Bangkok,
Thailand, p.561-574.
Donsakul, T. (1991). Chromosome study on five species
of channid fishes (Channa, family Channidae),
(from Thailand. Fac. Sci. Dept. Biol.); Wichian
Magtoon 29th Kasetsart Univ. Ann. Conf.
Bangkok (Thailand), 4-7 Feb 1991.
Fister, S. (1989). Karyotype analysis of a male carassius
auratus (Pisces, Cyprindae) caught in the river
Tamis. Acta Vet. Beograd, 39: 99-108.
Khuda-Bukhsh, A. R. (1996). Cytogenetical studies on
cold-water fishes with special reference to
trouts, snow-trouts, mahasheers and common
carps. In: H. R. Sing and W. S. Lakra (eds.),
Coldwater Aquaculture and Fisheries. Narendra
Publishing House, New Dehli, pp. 1-16.
Khuda-Bukhsh, A. R. and C. Chakrabarti (1999).
Distribution of C-band heterochromatin in
metaphase chromosomes of the silver crap,
Hypophthalmichthys molitrix (Gyprinidae,
Pisces). Proc. Zool. Soc. Calcutta, 52: 1-5.
Khuda-Bukhsh, A. R. and C. Chakrabarti (1996).
Localization of C- band hetrochromatin in Labec
calbasu (Pisces). In: A.G. Ponniah, P. Das and
S. R.Verma (eds.), Fish Genetics and
Biodiversity Conservation. NBFGR, Lucknow,.
pp. 405-407.
Khuda-Bukhsh, A. R. and S. Tiwary (1994). Study of G-
bands in two species of fish, Anabas testudineus
and Labec rohita. J. Inland Fish.  Soc. India, 26:
47-50.
Kligerman, A. D., S. E. Bloom and W. M. Howell
(1975). Umbra limi: a model for the study of
chromosome aberrations in fishes. Mut. Res.,
32: 225-233.
Lin, H. R. and R. E. Peter (1991). Aquaculture. In: I. J.
Winfield and J. S. Nelson (eds.). Cyprinid Fish:
Systematics, Biology and Exploitation,
Chapman and Hall, London, New York, Tokyo,
Melbourne, Madras, pp. 590-617.
Manna, G. K. (1989). Fish cytogenetics related to
taxonomy, evolution and monitoring aquatic
genotoxic agents. In: P. Das, and A. G. Jhingran
(eds.). Fish Genetics in India, Today and
Tomorrow Printers and Publishers, News Delhi,
pp. 1-20.
Mirza, M. R. and I. A. Sandhu (2007). Fishes of the
Punjab. Polymer Publications, Pakistan
Morescalchi, A. (1975). Chromosome evolution in the
caudata Amphibia. Evol. Biol., 8: 339-387.
NBFGR, (1998) . Fish Chromosome Atlas. In: A.G.
Ponniah and G. John (eds). National Bureau of
Bhatti et al J. Anim. Plant Sci. 23(2):2013
479
Fish Genetic Resources Special Publication.
No.1, Indian Council of Agricultural Research,
Lucknow, pp 129-134.
Rab, P. (1981) Chromosomal evolution of cyprinidae.
Reprodukce, genetika a hybnidizace ryb.
Vedecka 479 Conference, Milenovice 28-30.
Rijna. Pp. 184-189.
Rafique, M. (1992). Karyological analysis of the fishes
belonging to the subfamily Rasborinae from
Pakistan. M. Phil. Thesis, Quaid-Azam Univ.,
Islamabad 144 p.
Rafique, M. (2007). Biosystematics and distribution of
the freshwater fishes of Pakistan with special
reference to the subfamilies Noemachellinae and
chizothoracinae. Ph.D. dissertation. Deptt. Zool.,
Univ. Arid Agri. Rawal. Pakistan, pp. 1-253.
Rafique, M., M. Ahmad and S. Haque (2000).
Comparative karyomorphology of three fish
species belonging to the Genus Barilius
(Cyprinidae) from Pakistan. Pakistan J. Zool.,
32: 337-342.
Rishi, K. K. (1976). Karyotypic studies on four species of
fish. Nucleus., 19: 95-98.
Supiwong, W., P. Jearranaiprepame1 and A. Tanomtong
(2009). A new report of karyotype in the
chevron snakehead fish, Channa striata
(Channidae, Pisces) from Northeast Thailand.
Cytologia, 74: 317-322.
Thorgard, G. H. and S. K. Allen (1987). Chromosomes
manipulation and markers in fishery
management in population genetics and fishery
management (eds.). N. Ryman, F. Utter.
Washington Sea Grant Programe, Seattle,
pp.319-331.
Tripathi, N. K and O. P. Sharma (1987). Cytological
studies on six cyprinid fishes. Genetica, 73: 243-
246.
Zhang, S. M. and P. V. G. K. Reddy (1990). On the
comparative karyomorphology of three Indian
major craps, Catla catla (Hamilton), Labeo
rohita (Hamilton) and Cirrhinus mrigala
(Hamilton). Aquaculture, 97: 7-12.


KAYROTYPE OF SOL (CHANNA MARULIUS) FROM INDUS RIVER, PAKISTAN

http://citeseerx.ist.psu.edu/viewdoc/download;jsessionid=C5B237166C8B82E0D30CB09C8465F17A?doi=10.1.1.1045.5985&rep=rep1&type=pdf

KAYROTYPE OF SOL (CHANNA MARULIUS) FROM INDUS RIVER, PAKISTAN

Abstract

Similar works

Full text

Available Versions

CiteSeerX