The nutritive value of cassava leaf meal in pelleted feed for Nile tilapia | |
| Author | Ng, Wing Keong |
| Call Number | AIT Thesis no. AE-87-36 |
| Subject(s) | Tilapia Fishes--Feeding and feeds |
| Note | A Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Abstract | An assessment of the nutritive value of cassava leaf meal (CLM) as a dietary protein source in a pelleted tilapia diet was carried out . Two meals were prepared from either soaking or sun drying the cassava l eaves to determine a practical method to reduce its cyanide content . Isonitrogenous diets (30% crude protein) containing 0 , 20, 40 and 60% of the total protein supplied by either soaked or sundried CLM respectively were formulated. All diets were balanced by protein from fishmeal. An all plant protein diet containing 22% crude protein was a l so fed. The experimental diets were fed t o duplicate groups of Nile tilapia, Oreochromis niloticus L., for 10 weeks in a recirculating water system. An almost linear depression of growth and feed efficiency occurred with increasing l eve ls of CLM in the diet. There was no significant difference in the growth performance of the fish fed either the soaked or sundried CLM diets. The reduction in the specific growth rates of the fish expressed as a percentage of the control diet (all fishmeal protein) were approximately 20, 32, 53 and 93% when 20, 40, 60 and 100% of the total protein in t he diet were supplied by CLM, respectively. Good food conversion values we r e obtained for all diets except t he all plant protein diets . Protein efficiency ratio, apparent net protein utilization and protein digestibility all decreased with increasing CLM inclusion levels . Increased incorporation of CLM led to an increase in the car Cass moisture and ash content and a marked decrease in lipid content. Carcass protein was reduced only at the higher inclusion levels (above 60%) . There was no fish mortality and all the fish were morphologically normal. The sun drying of whole cassava leaves of the sweet variety was sufficient to render the meal safe to be incorporated in the fish pellet; no hydrogen cyanide toxicity symptoms were observed at t he l evels tested . Suppl ementation of t he all CLM protein diet with 0 .1% methionine tended to give improved growth performance (not statistically significant). It is postulated that cassava leaf meal is a viable partial dietary protein source for tilapia within the framework of developing countries. |
| Year | 1987 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Wee, Kok Leong |
| Examination Committee(s) | Edwards, Peter ;Lin, Chang Kwei |
| Scholarship Donor(s) | Canadian International Development Agency (CIDA) |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1987 |