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Fecundity of the Sole Euryglossa Orientais

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Fecundity of the Sole Euryglossa Orientais Fecundity of the sole Euryglossa orientalis (Bl. & Schn.)(family: Soleidae) from Karachi coast Item Type article Authors Khan, M.A.; Shamsul Hoda, S.M. Download date 23/09/2021 11:27:57 Link to Item http://hdl.handle.net/1834/31951 Pakistan Journal of Marine Sciences, Vol.3(1), 73-77, 1994 FECUNDITY OF THE SOLE EURYGLOSSA ORIENTALIS (BL. & SCHN.) (FA~Y: SOLEIDAE) FROM KARACHI COAST Mohammad Atiqullah Khan and S.M. Shamsul Hoda Centre of Excellence in Marine Biology, University of Karachi (MAK); Department of Zoology, University of Karachi, Karachi-75270, Pakistan (SMSH) ABSTRACT: During the present study fecundity of30 ovaries ofEuryglossa orienta lis was det~nnined. Fecundity ranged from 9922 to 83891 with a mean value of36361. The number 9fovain the dorsal lobe was less than that ofventral lobe. Log-log relationship between fecundity and total length, fish weight, ovary weight and ovary length were detennined. KEY WORDS: Sole- Euryglossa orienta lis- fecundity. INTRODUCTION Fec.imdity is a phylogenetic character of a fish and is dependent on various environmental factors, the fish might encounter in the different stages of its life history. The eggs production varies not only among different species but also within the same species, depending upon its length, weight of gonad etc. It is also influenced by the environment and even the geographical distribution is known to influence fecundity. In this study fecundity is defined as the number of oocytes at stage· IV-VI (when not running) before spawning (Kipling and Frost, 1969). Fulton (1891) :worked out on the fecundity of 112 fishes belonging to 3 9 marine species and concluded th<,1t larger fish produce the greater number of ova. Mitchell ( 1913) and Franz ( 1910) established a relationship between fecundity, age, length, weight of fish and weight of ovary. Other workers like Raitt (1933), Simpson (1951), Bagenal (1957, 1958, 1960a,b) and Kandler and Perwitz ( 19 58) also found the same type of relationship in flat fishes. MATERIALS AND METHODS A total of 745 fish of Euryglossa orienta/is were randomly sampled at fortnightly intervals from the commercial landing at Korangi Creek and West Wharf fish harbours, during April 1987 to June 1988. All specimens were kept frozen until required. Length and weight (after removal of moisture) of each spt'{cimen were recorded. The gonads were dissected out, measured, weighed, and preserved in 10% formaline to permit hardening of ova. For fecundity stuqy, a mid portion of both the lobes (dorsal and ventral) of mature ovary was weighed accurately in a torsion balance and all the mature ova, present therein, were counted. On the basis of the weight of the entire ovary, fecundity (F) was then computed as: 74 Pakistan Journal of Marine Sciences, Vol.3(1), 1994 where; W ov =total weight of the ovary; N 1 and N2 =number of ova from mid portion of the dorsal and ventral lobes, and WSt and WS2 =weight of the mid portion of the dorsal and ventral lobes of the mature ovary (Mac Gregor, 1957) . Fecundity thus estimated was studied in relation to several variables i.e., the weight and length of fish and the ovary by using regression analysis. Statistical treatment of biological data was done according to Zar (1974) (Table 1). Table I: Regresion equation for fecundity (F), total length {TL), weight of fish (Wr), weight of ovary (Wov ), lenght of right ovary (Lrov) and length of left ovary (I..Iov). Parameters N a b S.E.a S.E.b r 't' forr FtrL 30 -6.082 4.3890 1.7505 0.73490 0.750 6.0000 F/Wr 30 1.591 1.1746 0.3106 0.03990 0.743 5.8749 F!Wov 30 3.321 1.1000 0.0793 0.00625 0.934 13.8359 F!Lrov, 30 -1.100 2.6510 1.3730 0.67100 0.598 3.9473 F/Ltov 30 1.437 1.0930 ·o.9640 0.51800 0.370 2.1068 The number of eggs counted from female of the same size class were averaged and are presented in Table II as average fecundity count at 10 mm length groups. Mean fecundity of dorsal and ventral lobes at 10 mm length groups are also given in Table III. Table ll: Mean fecundity, number of eggs/g body and ovary weight in E. orientalis. Total No. of Mean Mean Mean No. of No. of No. of Length indivi- length wt. of wt. of eggs eggs/g eggs/g offish duals offish fish ovary (mean) bodywt. ovarywt. (mm) (mm) (g) (g) 190-199 1 197.0 133.00 5.30 18652 140 3519 200-209 2 202.0 134.15 4.85 10513 78 2168 210-219 4 211.8 160.77 4.55 9922 62 2181 220-229 5 224.2 194.06 6.94 21004 108 3026 230-239 2 233.5 173.50 7.40 17975 104 2429 240-249 5 243.8 234.58 11.44 29967 128 2620 250-259 1 259.0 264.40 7.80 15135 57 1940 260-269 4 262.5 306.32 14.55 39225 128 2696 270-279 1 ·278.0 440.50 34.30 83891 190 2446 280-289 1 287.0 348.60 18.20 42341 122 2326 290-299 2 297.0 560.65 18.40 65250 116 3546 300-309 2 302.5 518.50 23.00 82455 159 3585 190-309 30 249.85 289.04 13.06 36361 126 2706 Khan and Hoda Fecundity of the sole 75 Table ill: Mean number of eggs in dorsal (left) and ventral (right) lobes of E. orientalis. Tota11ength No. of Mean No. of eggs Mean No. of eggs of fish (nun) individuals in dorsal lobe in ventral. lobe 190-199 1 3776 14876 200-205 2 1173 9340 210-21~· 4 1268 8654 220-229 5 24111 18593 230-239 2 1513 16462 240-249 5 3434 26533 250-259 1 3178 11957 260-269 4 4654 34571 270-279 1 13957 69934 280-289 1 3918 38423 290-299 2 9968 55283 300-309 2 8730 73725 190-309 30 4832 31529 RESULTS AND DISCUSSION Fecundity counts from 30 ovaries of E. orienta/is were studied during the present investigations (Table II). The log-log relationship between fecundity (F) with total length (TL), weight of fish (Wf), weight of ovary (Wov), length of righ! ovary (Lrov) and length of left ovary (Llov) have been determined by the least square method.s are given in Table I. A direct relationship seems to exist between fecundity and total length and weight of the fish. The coefficient of correlation in both cases (length and weight) is 0.750 and 0.743 (Table I). Meanfecunditywas 36361 w1tharange of9922-83891 forthefishmeasuring210 mm TL and 279 nun TL respectively. The mean number of ova/gram body weight and ovary weight was determined to be 126 and 2987, respectively (Table II). The gonads are two lobes, dorsal (eyed side) and ventral (blind side).· The dorsal lobe is less fecund than that of ventral lobe (Table III). Fish length and fish weight were plotted against number of ova and linear relationships were obtained (Fig.1). 4 389 Fecundity increased in proportion to 4.389 power of length (F=l · ). In many other fish species such as plaice, the fecundity has been reported to increase either at · a rate of 3 times that of length (Simpson, 1951) or more as reported in haddock (Hodder, 1963). High fecundity in E. orienta/ismay be associated to bottom habitats, high local productivity and high temperature. According to Bagenal (1978) fish length is more suitable for making prediction of fecundity in the field with large samples and time limitations. 76 Pakistan Journal of Marine Sciences, Vol.3(1), 1994 •• UH a b 4.12 • u •. •• ~ 4.66 4.82 . / ~ w .... ~ HO § 4-H i ~w • • ... • 4.J4 4.JH • 3 • • 4.18 • • I • • 3.16 • J.B6 ~-:--~-:-:~----­ 1.11 2.n 2,;11 Mi 2.47 M l.l U l.J 2,4 2.~ M 2.7 LOU JOIAL Lfl::-f(l"I'H (IUi:l) !.oGWI:IG!fT(p,) 4.98 • c 4.98 4.82 •· 4.82 >1 d • ~ 4.66 • • s4.66 • ·./- ...,~450 . ~ 4,50 / :iiJ e4.3.j • • ··/· ~ 4..34 ••• tl ./.. • 0 •• ... g 4.18 • // ., •.;) 4.11:1 •• • ..;) 4.02 /'~ ...• 4.02 ••• lAt!• JhoJ.JUH.lQO Wov 3.86 3.86 .........._ _______ _ 0 Loi~J.lDI)-!1.651LosROv 0.4 0.6 0.8 1.0 1.2 '1.4 U!i 1.90 1.95 2.(lo 2.05 U 2.15 LOG OV AR.Y WEIGHT (g) I,OGI{IHH'I'IIVAKY I,I.:NHI'H (tnm) 4.12 .. e • • • 3.Ro • • ~ 3.64 • , ~ 3.411 • • ~ • • 3.32 • " . s Lo~!'o!,iJ7+1.09J LogLR Ov 3.16 •• • • :wo • •• 2.114 1.6 1.7 1.8 1.9 2.0 LOG- LEF'.f OVARY LEXG-lH (rum) Fig. 1. Log-log rclation~hips between fecundity and (a) total length~ (b) weight of fish; (c) ovary weight; (d) right ovary length; (e) left ovary length. Khan and Hoda: Fecundity of the sole 77 The ventral lobe is larger, heavier and more fecund than the dorsal one (Table III). Such difference between the fecundity of two lobes is in agreement with that in the dab Limanda limanda (Htun-Ham, 1978). REFERENCES Bagenal, T.B. 1957. Annual variation in fish fecundity. Journal oftheMarine BiologicalAssociation ofthe United Kingdom 36: 377-382. Bagenal, T.B. 19 58. The fecundity of clyde plaice. Journal of theMarine Biological Association ofthe United Kingdom 37: 309- 313.
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