World Journal of Fisheries & Aquaculture Sciences Research
Vol. 1, No. 2, November 2015
Table of Contents
A PRELIMINARY INVESTIGATION ON THE LENGTH-WEIGHT RELATIONSHIP CONDITION FACTOR, AND REPRODUCTIVE BIOLOGY OF SarotherodonmelanotheronAT RUMUOLUMENI MANGROVE CREEK, NIGER DELTA, NIGERIA.
Author: FAYEOFORI G. BOB-MANUEL
Pages: 1 - 8
A preliminary investigation was carried out to study some aspects of the biology of Sarotherodonmelanotheron at Rumuolumeni mangrove creek in the Niger Delta. The length-weight relationship showed a curvilinear one. It was observed that the condition factors are higher in the younger fish than the older ones. Fecundity was observed to be higher among the medium-sized fish than the younger ones. However it was generally indicated that mouth-brooding tilapia produce less eggs to enable the parents cope with their protection and survival. The study also revealed their small size at maturation. The small size at sexual maturity is common among tilapia species which attain sexual maturity as early as 3-months. Three stages of gonad development was identified, ovary size increased with increase in fish size but the GSI is highest for the smallest fishes and lowest for the largest ones. It was also opined that the pollution of the Niger Delta aquatic ecosystem resulting from the exploration and exploitation of oil could also result in the stunting of the fish. Copyright © WJFASR, all rights reserved.
KEY WORDS: Sarotherodonmelanotheron, length-weight relationship, reproductive biology, Niger Delta.
DIGESTIBILITY POTENTIAL AND PERFORMANCEOF SOME FEED INGREDIENTS IN THESHARP-TOOTH CATFISH Clariasgariepinus FINGERLINGS
Author: Fayeofori G. Bob-Manuel
Pages: 1 -8
A study was carried out to evaluate the nutritional value of some feed ingredients so that their specific contribution can be ascertained in terms of their specific input to growth and digestibility in fish. Five feed ingredients were assessed namely blood meal, yeast single cell protein, fish meal, spent grain and wheat bran. The results indicated that diet D4 (Spent grain) had the highest values in terms of percentage weight gain (PWG) – 91.47% as well as specific growth rate (SGR) – 4.40%. The values for the mean weight gain (29.80) and Nitrogen metabolism (450.58) for diet D4 were next best to D1 (30.30) and D2 (458.14) respectively. The diet D4 also gave the highest ADC protein value (99.80). It could be deduced from this that spent grain (D4) was well utilized for growth by C.gariepinusfingerlings and very highly digestible. It is therefore recommended as a good substitute for fishmeal in the diet of C.gariepinus. Copyright © WJFASR, all rights reserved.
KEY WORDS: Clarias gariepinus, digestibility, feed ingredients, growth.
© Copyright World Journal of Fisheries & Aquaculture Sciences Research • All rights reserved.