www.symbiosisonline.org Symbiosis www.symbiosisonlinepublishing.com Research article International Journal of Poultry and Fisheries Sciences Open Access Morphometric Characters and Meristic Counts of Black Chin Tilapia (Sarotherodon melanotheron) From Buguma, Ogbakiri and Elechi Creeks, Rivers State, Nigeria Akinrotimi OA1*, Ukwe OIK2 and Amadioha F3 1African Regional Aquaculture Center of Nigerian Institute for Oceanography and Marine Research, Port Harcourt, Rivers State, Nigeria 2,3Department of Fisheries, Faculty of Agriculture, Rivers State University of Science and Technology, Nkpolu-Oroworkwo, Port Harcourt, Rivers State, Nigeria Received: December 04, 2017; Accepted: January 06, 2018; Published: January 09, 2018 *Corresponding author: Akinrotimi OA, African Regional Aquaculture Centre of Nigerian Institute for Oceanography and Marine Research, Port Harcourt, Rivers State, Nigeria, Tel: +2348065770699; E-mail:[email protected] to date [5]. Morphological differences based on general body type Abstract or unusual anatomical forms have been used to distinguish and An experiment was carried out to assess the morphometric compare among species and groups dimensions have been used measurements and meristic counts of black jaw tilapia, Sarotherodon melanotheron (Ruppell, 1852) from Buguma, Ogbakiri and Elechi creeks, Rivers State, Nigeria. The study was done to determine racial to describe fish body shape [6]. variations between this specie in the three environments. Fifty work and plays a key role for the behavioral study. Morphometric specimens were collected monthly from each location between April measurementsIdentification and of speciesmeristic is acounts primary are step considered towards any as research easiest and June 2017. The results revealed that they were phenotypically P < is termed as morphological systematic [7]. Morphological 0.05) were recorded in body depth, and caudal peduncle length in each and authentic methods for the identification of specimen which separable populations of the same species. Significant differences ( measurements, meristic counts, provide data useful for taxonomic which were suggested to have occurred as a result of difference in the environmentalmonth between conditions the fish sampled in the three from creeks. Buguma The and results other also two implied creeks, morphological traits both within and between populations than otherstatus vertebrates[8]. In general, and are fish more demonstrate susceptible greater to environmentally variances in breeding programmes. induced morphological variations. The cause of variation in the that fish from Buguma creek could be preferable as brood stock for Key words: Tilapia; Morphometrics; Meristics; Racial Variations; morphometric and meristic characters may range from variability Niger Delta; parameters [9]. The morphometric relationships between Introduction to the intraspecific which is under the influence of environmental Tilapia culture has increased in Nigeria in recent times. This of individuals and to determine possible difference between various body parts of fish can be used to assess the well being is particularly because of its fast growth and the fact that it can separate unit stocks of the same species [10]. Fish are very sensitive to environmental changes and quickly adapt themselves the country [1]. However, after decades of introduction and by changing necessary morphometrics [11]. Information on the easily reproduced in many confined water bodies throughout of geographical locations and have shown phenotypic variations relationship among them are essential for taxonomic work. domestication of the fish, they have highly adapted to a wide range morphometric measurements of fishes and the study of statistical with respect to the pure tilapia strains of the brood stock [2]. This Sarotherodon melanotheron (Ruppell, 1852) is typical may be due to the effects of the environment or due to the hybrids estuarine specie which can be found in abundance in most of evolved through extensive intra breeding [3]. In this context, the lagoons, creeks and estuaries of West Africa and supports a natural morphometric/meristic data are of great importance for improvement of aquaculture. Morphometric and the meristic range of salinities. They have adapted to diverse habitats such as methods remains the simplest and most direct methods of permanentmajor lagoon and fishery temporary [12]. They rivers, can large live equatorialand reproduce lakes, in tropical a wide and subtropical rivers, open and closed estuaries, lagoons, morphometric characters or meristic counts remains the most swampy lakes, deep lakes and coastal brackish lakes [13]. These species identification [4]. Analysis of phenotypic variation in advent of techniques which directly examines biochemical major species caught within the brackish water areas and there orcommonly molecular used genetic method variation, to delineate these stocks conventional of fish despite methods the fishes have a great economic importance, ranking among the particularly in areas of high or variable salinities, characteristic is an increasing interest in this fish for aquaculture purposes, continues to have an important role in stock identification even Symbiosis Group * Corresponding author email: [email protected] Morphometric Characters and Meristic Counts of Black Chin Tilapia (Sarotherodon Copyright: melanotheron) From Buguma, Ogbakiri and Elechi Creeks, Rivers State, Nigeria © 2018 Akinrotimi OA, et al. of the estuaries and extensive lagoon systems which constitute Sample Collection S. melanotheron were notits natural been exploited. range [14]. Therefore, In most parts the present of Niger investigation Delta, an assessment is aimed of morphometric differentiation of indigenous fish species has Collected A total samples of fifty were (50) placedspecimens individually of into plastic bags at examining the morphormetrics and meritic variability in S. collected monthly from fishermen catch in the three creeks. melanotheron from three creeks (Buguma, Ogbakiri and Elechi) and kept in ice box, until transportation to the laboratory. The in Rivers State, Niger Delta, Nigeria. This study will provide specimens were transported in ice chest to the laboratory, where information on the contribution and effect of environmental measurements started immediately to avoid shrinkage. factors to the morphomeristic characteristics of these species. Morphometrics and Meristic Measurement Materials and Methods was made to the nearest centimetre, using divider, transparent Research Place and Duration ruler Forand each a measuring fish, nine board. morphometric The meristic measurements counts (Table (Table 2), was 1), The research was conducted in the laboratory of the Department of Fisheries and Aquatic Environment, Rivers State University, Port Harcourt, from April to June, 2017. carried out by counting the number of soft rays on five fins on the bodyTable of 1 the: Morphometric fish Characters Descriptions of S.melanotheron Sampling Location Characters Descriptions The samples was collected monthly from Buguma, Ogbakiri Distance from the tip of the snout to the 1. Total length (TL) and Elechi Creeks, in Rivers State, Nigeria they were located on the lower reaches of New Calabar River (Figure 1). Distance from the tip of the snout to the 2. Standard length (SL) longest caudal fin ray Elechi Creek, South-West of Port Harcourt metropolis, lies end of the vertebral column Distance from the tip of the snout to the 3. Head length (HL) posterior margin of the opercula between longitude 6°45”E and 7°20”N and latitude 4°38”N Estuary and includes its adjoining mangrove Creeks situated near Eye Diameter (ED) Diameter of the eye theand Eagle5°5”E. Island The creek by the is aRivers tributary State of Universitythe upper limitsof Science of Bonny and 5. Caudal Peduncle Technology, Nkpolu, Port Harcourt (Figure 1). The vegetation is 4. Length of the peduncle predominantly mangrove. While Buguma creek is located in Asari Length(CPL) Toru Local Government Area of Rivers State. It is located between Pre Dorsal Length Distance from the tip of the Mouth to (PrDL) 6. The Buguma creeks systems consist of the main creek channel 7. Pre Orbital Length From tip of snout to anterior margin longitude 60° 47’E and 60° 59’E and 40° 36’N and 40° 59’N. the dorsal fin base and associated inter connecting creeks, which interconnect (PrOL) of eye and surround Buguma and other communities. Ogbakiri creek 8. Post Orbital Length From posterior margin of the eye to is located in the lower reaches of New Calabar River. This area (POL) posterior margin of opercula consist of some settlements/communities whose main activities 9. Maximum Body Depth The vertical distance between the livelihood (MBD dorsal and ventral margins of the is fishing and cultivation of crops which are their source of Table 2: Meristics Measurements and the Abbreviations Characters Abbreviations DFR 1. Number of the Dorsal fin soft rays AFS 2.3. Number of AnalCaudal fin Fin soft Soft rays Rays CFR PFR 4.5. Number of thePelvic Pectoral Soft Fin fin Rays soft rays PVR Evaluation of Water Quality Parameters During the study, the following water quality parameters temperature, hydrogen ion concentration (pH), dissolved oxygen (DO), and salinity were monitored monthly in the different creeks. Water temperature measurement was taken in situ by using Figure 1: Map of Niger Delta Showing the Sampling Sites. (pH) was determined in situ by the use of a pH meter (Model HImercury