Effects of dietary cottonseed meal protein levels on growth and feed utilization of Nile tilapia, Oreochromis niloticus L

The nutritional suitability and cost effectiveness of cottonseed meal (CSM) as protein source in the diet of Nile tilapia (Oreochromis niloticus L.) with mean initial weight 4.24±0.20 g, was evaluated over a 56-day growth period. Four isonitrogenous (320 g kg-1), isolipidic (100 g kg-1) and isoenergetic (18 KJ g-1) test diets were formulated in which CSM protein replaced fish meal (FM) protein at levels of 0% (control), 25%, 50% and 75%. The control diet had FM as the sole protein source. The growth experiment was conducted in plastic tanks in a recirculation system each dietary treatment was in triplicate. After 56 days of feeding fish at 6% - 4% body weight per day, CSM protein replacements of 25% and 50% did not significantly (

Nutritional composition of shea nut (Vitellaria paradoxa, gaertn) byproducts and their digestibility by Nile tilapia (Oreochromis niloticus L.) juvenile

This study was conducted to determine the nutritional (proximate and energy) composition of selected shea nut by-products (SNPs) namely; shea nut meal (SNM, solvent extracted), shea nut cake (SNC, mechanically extracted) and shea nut cake (SNCW, water extracted) and their apparent digestibility coefficient (ADC) by Nile tilapia, Oreochromis niloticus. The ADC was determined using a reference diet with chromic oxide indicator and test diets that contained 70% reference diet and 30% of SNPs being evaluated. Nile tilapia (26.89 ± 3.19 g) was stocked in rearing tanks at 12 per tank and their faeces was collected from two replicate groups of fish by siphoning. Crude protein (CP), crude lipid (CL), crude fibre (CF) and gross energy (GE) of SNM, SNC and SNCW were 159.8, 70.0, 86.6 g.kg-1 and 17.4 kJ.g-1; 145.3, 243.2, 49.3 g.kg-1 and 21.7 kJ.g-1; 125.5, 304.0, 48.8 g.kg-1 and 22.9 kJ.g-1, respectively. The ADC of dry matter (DM), CP, CL and GE of ingredients ranged from 73.0 – 83.8%, 47.3 – 72.0%, 74.7 - 98.9% and 61.2 - 96.3%, respectively. The SNC and SNCW had significantly higher DM, CP, CL and GE digestibility (P < 0.05) compare to SNM. Generally, protein composition and digestibility of the SNPs in this study were low and seem unsuitable as protein sources for Nile tilapia.Keywords: Nutritional composition, digestibility, nile tilapia, shea nut, by-produc