Iran. J. Ichthyol. (December 2018), 5(4): 267-276 Received: June 29, 2018 © 2018 Iranian Society of Ichthyology Accepted: November 01, 2018 P-ISSN: 2383-1561; E-ISSN: 2383-0964 doi: 10.22034/iji.v5i4.287 http://www.ijichthyol.org Research Article Age, growth, sex ratio, spawning season and fecundity of Capoeta razii from Sefid River in the southern Caspian Sea basin Kobra GHASEMZADEH-SARCHESHMEH1, Hamed MOUSAVI-SABET*1,2, Masoud SATTARI1,2, Saber VATANDOUST3, Mohaddeseh AHMADNEZHAD4 1Department of Fisheries, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran. 2The Caspian Sea basin Research Center, University of Guilan, Rasht, Iran. 3Department of Fisheries, Faculty of Natural Resources, Babol branch, Islamic Azad University, Babol, Iran. 4Inland Waters Aquaculture Research Center, Iranian Fisheries Sciences Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Bandar Anzali, Iran. *Email: [email protected] Abstract: Some aspects of reproductive biology of Capoeta razii, an endemic cyprinid species from the Sefid River in the southern Caspian Sea basin, were studied by monthly sampling throughout a year. Age, growth, sex ratio, spawning season, fecundity, gonado- somatic, modified gonado-somatic and Dobriyal indices were estimated. The sex ratio (F: M) was obtained as 1.00:2.63, and the percentage of males was greater than females. The mature males and females were longer than 88 and 148 mm in total length, and 1+ and 2+ in age, respectively. The spawning of C. razii took place from late May to late August when the water temperature was between 19.7 and 22.8◦C. At the beginning of the reproduction period, the average gonado-somatic index values were 10.0% ranging from 4.03% to 15.90% in ripe females. The estimated gonadal indices showed that the ripe males were ready to spawn earlier than females. The average egg diameter was 0.99±0.65, ranging from 0.2 to 2.3 mm. The averages absolute and relative fecundity were 4386±2174 and 66.3±37.8, respectively. The absolute fecundity was significantly related to body weight and gonad weight. Keywords: Reproductive biology; Oocyte diameter; Gonado-somatic index; Spawning season. Citation: Ghasemzadeh-Sarcheshmeh, K.; Mousavi-Sabet, H.; Sattari, M.; Vatandoust, S. & Ahmadnezhad, M. 2018. Age, growth, sex ratio, spawning season and fecundity of Capoeta razii from Sefid River in the southern Caspian Sea basin. Iranian Journal of Ichthyology 5(4): 267-276. Introduction region (Aghili et al. 1999). One of the predominant The genus Capoeta Valenciennes, 1842 has a wide fishes in its River is C. razii (Heidari et al. 2013, distribution in Iran containing about 18 species 2014a, b). (Esmaeili et al. 2018). Capoeta razii is commonly There are available some morphological studies found in the southern Caspian Sea basin, north of Iran on this species from the Caspian Sea basin (Heidari (Jouladeh-Roudbar et al. 2017). The southern et al. 2013), and some biological studies on the genus Caspian Sea basin encompasses 156000 km, about from the Caspian Sea basin and the Tigris River 15.5% of the whole country (Coad 2017). This basin drainage (Unlu 1991). Also, few researches have is located in the European area of the Eurasia been carried out on the reproductive biology of this (Banarescu & Coad 1991) and is one of the most genus in Iran and Turkey (Duman 2004; Kalkan various freshwater ecosystems in Iran (Coad 1995). 2008; Sen et al. 2008; Rezai et al. 2009; Patimar & Sefid River is the most important river in the southern Farzi 2011; Poria et al. 2014; Javaheri & Taghavi Caspian Sea basin, with about 765 km length in this Niya 2014). 267 Iran. J. Ichthyol. (December 2018), 5(4): 267-276 Fig.1. Location of the sampling site in the southern Caspian Sea basin, Sefid River, in north of Iran. As studies on the reproductive biology of endemic 199.5 mg.L-1. fish species are necessary for stock management and To examine the monthly changes in gonads as a conservation programs, and as there is no available mean for estimating the spawning season of C. razii, detail about reproductive aspects of C. razii, therefore three indices were used: GSI (gonado-somatic this study aimed to investigate various aspects of index), MGSI (modified gonado-somatic index) and reproductive biology of this species in the southern D.I. (Dobriyal index). In order to determine the GSI Caspian Sea basin. (GSI= [Wg × Wb–1] ×100) (Nikolski 1963), MGSI –1 (MGSI= [Wg × Wb ] - Wg × 100 (Nikolski 1963), Materials and Methods and D.I. (D.I.= 3√Wg) (Dobriyal et al. 1999), ovaries A total of 320 individuals of C. razii were collected also were weighed (Wg) with 0.001g accuracy. The from lower parts of Sefid River (37°01'16.82"-36° absolute fecundity (Fa) was estimated in 24 ovaries 50'44.71"N; 49°37'56.86"-49°35'01.23"E), in the by calculating the number of oocytes with a diameter southern Caspian Sea basin (Fig. 1). Fish were greater than 0.2mm. The relative fecundity (Fr) was collected monthly from November 2013 to October expressed by dividing the Fa by the fish body weight. 2014 by electrofishing device (200-300 V), with The result was presented as the number of eggs per mesh size of 0.2cm. After anesthesia, the collected gram of body weight (Bagenal 1967). To determine specimens were fixed in 10% formaldehyde, the ovum diameter, the ovaries were preserved in measured (TL: total length, SL: standard length to the Bouin’s fixative for 24 hours. The diameters of 30-60 nearest 0.1mm) and weighed (Wb: body weight to ova of each female were measured using a Zeiss the nearest 0.01 g). Two samplings per month were stereomicroscope model SV 6 fitted with an ocular done at the peak of spawning time. The analysis of micrometer. water throughout the year showed that the The Chi-square test was used to assess deviation temperature was 9.4-26.7°C, pH 7.29-8.04, dissolved from a 50:50 sex ratio (Robards et al. 1999). In order oxygen 5-10mg.L-1, and the water hardness 175- to compare significant differences in the GSI 268 Ghasemzadeh-Sarcheshmeh et al.- Age, growth, sex ratio, spawning season and fecundity of Capoeta razii from Sefid River Table 1. Standard length (SL), total length (TL) and body weight (Wb) (mean ±SD) in different age classes of males and females Capoeta razii from Sefid River. Age N SL (mm) TL (mm) Wb (g) M F M F M F M F 1+ 22 15 665.0±0.47 58.4±0.70 8.09±0.58 7.09±0.77 6.71±2.04 4.22±1.30 2+ 125 41 127.0±1.40 75.0±1.47 14.7±1.63 9.02±1.78 13.54±6.51 8.94±5.81 3+ 67 15 116.0±1.28 124.0±12.97 13.73±1.42 14.68±3.01 29.96±9.38 41.97±23.99 4+ 13 13 136.1±1.54 158.1±15.81 16.11±1.63 18.65±2.21 52.88±18.75 73.38±30.75 5+ 1 - 166.0 - 175.0 - 53.07 - Table 2. Absolute (Fa) and relative (Fr) fecundity in particular ranges of body length (SL), body weight (Wb) and age classes of females of Capoeta razii from Sefid River (n = number of specimens). Parameters n Fa Fr Range Mean ±SD Range Mean ±SD 122.1-142 7 2293-8242 4255±2118 53-186 95±46 SL (mm) 142.1-162 11 1987-8315 4800±2456 32-124 65±28 162.1< 6 1777-6480 3778±1558 20-52 35±12 32.1-60 9 2045-8242 3728±1979 39-186 84±45 Wb (g) 60.1-90 10 1777-8315 4702±2515 20-62 62±33 90.1< 5 2390-6667 4937±1876 16-65 44±16 2+ 1 3197-00 3197±00 20-00 99±00 Age 3+ 10 1777-8242 3970±2360 20-186 74±48 4+ 13 1987-8315 4796±2106 24-117 57±29 between samples taken on various months, the longer and heavier than the males and achieve analysis of variance was applied (P<0.05). The maturity later than males. At the age of 1+, TL was strength and significance of the relationship between higher than 80.0mm and body weight was about 6g. the absolute fecundity and selected individual The results revealed that this population of C. razii features of the females included in this study (body had a narrow age range of 1+ to 5+ years. Most of the length and weight, the gonad weight and the fish’s sampled fish were 2+ (49.68%) and 3+ (15.61%) age) were analyzed by calculating Pearson’s years old, some were 1+ (11.87%) and 4+ (7.18%), correlation coefficient r (P<0.05) and regression and only one specimen was 5+ (0.31%). The oldest equations. The data were analyzed using SPSS females were 4+ years old and the oldest male were Version 16.0 software package and Microsoft Excel 5+ years old (Table 1). 2010. Significant differences in male and female DI, GSI and MGSI in different months were observed Results (P<0.05). There were no significant differences Of 320 collected specimens, 229 males, 87 females between GSI and MGSI in the same month. and 4 immatures were examined. Sex ratio of the total Assessment of the spawning season for C. razii in the samples (over all the seasons) was F1.00:M2.63 Sefid River was based on the examined gonadal accounting for 27.54% females and 72.46% males.