El-Dahhar,, A. (2000). EFFECT OF DIETARY ENERGY AND PROTEIN LEVELS ON SURVIVAL, GROWTH AND FEED UTILIZATION OF STRIPED MULLET Mugil cephalus LARVAE. Journal of Animal and Poultry Production, 25(8), 4997-5010. doi: 10.21608/jappmu.2000.259614
A. A. El-Dahhar,. "EFFECT OF DIETARY ENERGY AND PROTEIN LEVELS ON SURVIVAL, GROWTH AND FEED UTILIZATION OF STRIPED MULLET Mugil cephalus LARVAE". Journal of Animal and Poultry Production, 25, 8, 2000, 4997-5010. doi: 10.21608/jappmu.2000.259614
El-Dahhar,, A. (2000). 'EFFECT OF DIETARY ENERGY AND PROTEIN LEVELS ON SURVIVAL, GROWTH AND FEED UTILIZATION OF STRIPED MULLET Mugil cephalus LARVAE', Journal of Animal and Poultry Production, 25(8), pp. 4997-5010. doi: 10.21608/jappmu.2000.259614
El-Dahhar,, A. EFFECT OF DIETARY ENERGY AND PROTEIN LEVELS ON SURVIVAL, GROWTH AND FEED UTILIZATION OF STRIPED MULLET Mugil cephalus LARVAE. Journal of Animal and Poultry Production, 2000; 25(8): 4997-5010. doi: 10.21608/jappmu.2000.259614
EFFECT OF DIETARY ENERGY AND PROTEIN LEVELS ON SURVIVAL, GROWTH AND FEED UTILIZATION OF STRIPED MULLET Mugil cephalus LARVAE
Animal and Fish Production Department, Faculty of Agriculture (Saba Basha), Alexandria University, P.O Box 21531, Bolkly Alexandria Egypt
Abstract
Two experiments were carried out to determine the effect of dietary energy and protein levels on survival, growth and feed utilization of striped mullet (Mugil cephalus) larvae in glass aquaria. In experiment 1, seven metabolizable energy (ME) (175, 190, 205, 220, 235, 250 and 265kcal/100g diet) in isonitrogenous (26% crude protein) feeding mixtures replicated three times were used to feed striped mullet larvae (0.173 ± 0.02g mean initial body weight, BW) for eight wk. In experiment 2, a 3 ´3 factorial design was employed in which nine test diets containing three levels of ME (200, 225 and 250kcal/ 100g) each with three dietary crude protein levels (18, 22, and 26%) were used to feed striped mullet larvae (0.33g initial BW) for eight weeks. Increasing dietary ME in experiment 1, resulted in significant (P< 0.01) increase in each of final body weight (FBW), BW gain, feed consumption, survival, specific growth rate (SGR), protein efficiency ratio (PER), protein productive value (PPV) and energy retention (ER) of striped mullet larvae of 0.173g initial BW. These increase were up to 235 kcal ME /100g diet. However, increasing ME in the diet beyond 235 kcal /100g did not exert any additional significant increase in any of these criteria (P > 0.05). In experiment 2, increasing dietary protein and ME also resulted in significant (P< 0.01) increase in all these measurements that taken on striped mullet (0.33g initial BW). Larvae that get increasing dietary ME from 200 to 225 kcal /100g diet, did not exhibit any significant increase in all measurements (P > 0.05). However, increasing dietary ME from 225 to 250 kcal /100g diet, resulted in significant increase in all these measurements and improved feed conversion ratio (FCR) (P < 0.01). Likewise, striped mullet larvae that get increasing dietary crude protein from 18 to 22 and to 26% exhibited significant (P < 0.01) increase in all estimated measurements and improved FCR. Body protein and fat contents also increased significantly (P<0.01) as ME increased from 175 to 235 kcal /100g diet in experiment 1 and from 200 to 250 kcal /100g diet in experiment 2. They also increased significantly (P < 0.01) as dietary crude protein increased from 18 to 22 and to 26% in experiment 2. On the other hand, moisture contents of the fish body decreased significantly (P<0.01) as ME increased up to 235 kcal /100g diet in experiment 1 and from 200 to 225 kcal /100g diet in experiment 2. It also decreased significantly (P < 0.01) as dietary crude protein level increased from 18 to 26%. In the conclusion of experiment 2, interaction between dietary crude protein and ME was also found to be significant (P < 0.01) for all the variables determined in experiment 2. They get the best values for striped mullet larvae maintained at 26% dietary crude protein with the medium level of energy 225kcal ME/100g diet and 22% dietary crude protein with the high level of energy 250kcal ME/100g diet. From this data it could be seen that the best level of ME was 235 kcal /100g diet when the diet containing 26 % crude protein. But, when the ME increased to 250 kcal /100g diet in experiment 2, dietary crude protein could be lowered from 26 to 22%.