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Pellucida and Schilbe Intermedius in the Mid Cross River Flood System, Southeastern, Nigeria

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Pellucida and Schilbe Intermedius in the Mid Cross River Flood System, Southeastern, Nigeria American Journal of Science and Technology 2015; 2(4): 183-187 Published online July 10, 2015 (http://www.aascit.org/journal/ajst) ISSN: 2375-3846 Sex Ratio, Gonad Maturation and Condition Factor of Parailla pellucida and Schilbe intermedius in the Mid Cross River Flood System, Southeastern, Nigeria Uneke Bilikis Iyabo *, Alionye Grace Dept. of Applied Biology, Faculty of Biological Sciences, Ebonyi State University, Abakaliki, Ebonyi State, Nigeria Email address [email protected] (U. B. Iyabo) Keywords Sex Ratio, Citation Gonad Maturation, Uneke Bilikis Iyabo, Alionye Grace. Sex Ratio, Gonad Maturation and Condition Factor Parailla Condition Factor, pellucid and Schilbe intermedius in the Mid Cross River Flood System, Southeastern, Nigeria. Parailla pellucida, American Journal of Science and Technology. Vol. 2, No. 4, 2015, pp. 183-187. Schilbe intermedius and Cross River Abstract Aspects of the reproductive biology such as sex ratio, gonad maturation and condition factor of Paraiha pellucida and Schilbe intermedius, was investigated in the mid Cross river flood system. Sampling was done for 7 months (January to March and May to Received: June 1, 2015 August). In the laboratory, the specimens were investigated for sex ratios, gonad Revised: June 15, 2015 maturation and condition factor. A total of 208 fishes of the two species were collected. Accepted: June 16, 2015 The overall sex ratio males/females in Parailla pelluada (1:0.7) showed that males (n = 64) were more than females (n = 47) while overall males/females in Schilbe intermedius sex ratio of (1:1.2) showed that females (n = 52) were more than males (n = 45). The gonad maturation stage was determined by measuring the immature, mature, ripe and spent gonad stages of the two species, and their monthly percentage occurrence determined. The monthly condition factor of the two species showed that they were in poor condition throughout the sampling months except for the month of August which recorded good condition for males of P. pellucida. The chi-square of the males/females of the two species were significance P. pellucida (X 2cal = 1.41 > X 2tab = 0.352) and S. intermedius (X 2cal = 0.495 > X2tab = 0.352). 1. Introduction Fish plays important role in the development of a nation. Apart from being a cheap source of highly nutritive protein, it also contains other essential nutrients required by the body (Sikoki et al ., 1999). Fisheries provide a significant part of national inland fisheries production (up to 61%). The length-weigh relationship and population structure of fish are important fishery management tools. Fisheries provide employment for about 20,000 rural households, and it is the second largest source of total income (24-28%) for the same households. Fish is an important protein food for fishers household (20% catch is consumed on average) and is also supplied to the large urban markets of Nigeria, including Lagos, Kano and Ibadan. Processed fish (mainly dried clariid catfish) is a highly valuable trade item, with thousands of people employed in the marketing chain, processor, transporter, merchants (Neiland et al ., 1997). Fish is one of our most valuable sources of proteinous food. Worldwide, people obtain 25% of their animal protein from fish and shell fish. About 35% of all fish is eaten fresh, chilled or frozen. It is also cured or canned (16% American Journal of Science and Technology 2015; 2(4): 183-187 184 each) or made into oil and fish meal (32%). Fish and marine species are included in this family. This fish is elongated and products are used as medicine, ground into vitamins or has a distinctive wide longitudinal black line that extents the processed into cosmetics and perfumes, lubricants, varnishes, length of the body. Le Cren (1951), Satran (1992) Petrakis and soap and margarine. Whales, seals and oysters are valued for Strergious (1995), Hickley and Bailey (1987), Merron and many of the above uses. Industries process many inferior fish Mann (1995), Omondi and Ogari (1994), Ogari et al. (1995) and fish waste products into glue livestock feed and fertilizers. had reported on aspects of biology of fish generally and Scientists often use fish especially goldfish for experiments members of family Schilbeidae in various African and medical research. Many people enjoy keeping goldfish, rivers/lakes. Thus this study seeks to determine the population guppies, tetras and other fish as pets in home aquariums. structure of two fish stocks Parailla pellucida and Schilbe Angling is a popular pastime in all parts of the world. In many intermedius in the mid Cross river flood system, to determine maritime nations such as Peru, Japan, China and Russia, fish the gonad maturation of the two species of fish and to forms a valuable daily diet as well as export item. Schilbedae determine the condition factor of the fish stocks. is a family of coastal pelagic fishes that are found over the continental slope. They are sometimes referred to as hard head 2. Materials and Methods or glass fish. They are found throughout Africa and Asia. They include the genera Eutropieus, Parailla and Schilbe. About 45 2.1. Study Area Fig. 1. Map of Afikpo North Local Government Area showing the sampling locations in the Cross River basin (Okoh et al., 2007) 185 Uneke Bilikis Iyabo and Alionye Grace: Sex Ratio, Gonad Maturation and Condition Factor Parailla pellucid and Schilbe intermedius in the Mid Cross River Flood System, Southeastern, Nigeria The study was carried out in the upper cause of the Cross 52.The overall sex ratio males/females in P. pellucida (1:0.7) River Basin, located at Ozziza in Afikpo North Local showed that males (n=64) were more than females (n=47). Government Area of Ebonyi State. The area is about 5km While the overall males/females in S. intermedius sex ratio of eastwards away from Afikpo main town. The Cross River (1:1.2) showed that females (n=52) were more than males Basin forms the border between Ebonyi State and Cross River (n=45). The percentage number of male fishes in P. pellucida State. The vegetation around the river is predominantly in immature is 20(31.3%), mature 26(40.6%), ripe 11(17.2%) grasses, tall and thin palm tresses, bamboo tress and elephant and spent 7(10.9%) while that of females in immature is grasses unevenly distributed. Hence, the vegetation, 13(27.7%), mature 16(34.0%), ripe 12(25.5%) and spent ecological built of the area attracts some activities like 6(12.8%) respectively. In males of P. pellucida the mature recreation (escortion and picnic, fishing, limbering, farming stage has the highest percentage number with 26(40.6%) and sand mining due to the presence of sand beaches).There is while spent has the lowest percentage number with 7(10.9%). a "mini 7 market around the river where some of the fishes are And in females, the mature stage has the highest percentage marketed immediately they are caught. However, most of the number with 16(34.0%) while the spent has the lowest fishes caught are transported to other part of Ebonyi and Cross percentage number with 6(12.8%) (Table 1). In S. intermedius, River States. There is also water fluctuation in the Cross River the percentage number of males fishes in immature is Basin with each season and this goes a long way to determine 13(28.9%), mature 24(53.3%), ripe 5(11.1%) and spent the agricultural activities of the occupants during each period. 3(6.7%) while that of females in immature 15(28.8%) mature During the dry season (Nov-March), some areas of the river 25(48.1%, ripe 7(13.5%) and spent 5(9.6%) respectively. In floor is seen and is covered with sand, hence fishing activities males of S. intermedius, the mature has the highest percentage will be hampered. During the rainy season (April-September), with 24(53.3%) while the spent has the lowest percentage water level increase and reverses the activities of the number with 3(6.7%). In females, mature has the highest fishermen to fishing. percentage number with 25(48.1%) while the spent has the lowest with 5(9.6%) (Table 2).The overall condition factor for 2.2. Sample Collection P. pellucida was 0.57 and for S. intermedius was The fishes used for this study were caught by local 0.46.Condition factor for males of P. pellucida was 0.64 and fishermen at Beach in Afikpo using locally available crafts 0.50 females). Monthly condition factor for P.pellucida was and fishing gears. The ones used mainly are canoes, gillnets, highest (1.13) in the month of August in males while the hooks and line. The experimental fish, Schilbe species, caught lowest (0.45) was in the month of January in females (Table were collected and transported in ice-chest to Applied Biology 3).Males of S. intermedius had condition factor of 0.46 while Laboratory, Ebonyi State University, where they were the females has the condition fact of 0.46. The highest preserved in 10% formalin to avoid decay before the condition factor (0.58) was in the month of May for males and necessary experiments were carried out. in August for females in S. intermedius while the lowest (0.26) was in the month of March in females (Table 4). However, all 2.3. Laboratory Analysis the fishes during the sampling months were not in good condition expect in the month August (1.13). In the laboratory, the fishes were sorted out and identified to species level using key provided by Olaosebikan and Raji Table 1. The dynamic of male/female P.
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