ABSTRACT
The present study was performed to investigate the effect of feeding different levels of poultry by-product meal as untraditional ration constituents on fish performance, and apparent digestion coefficients.
A total number of 90 apparent healthy Nile tilapia fingerlings were randomly distributed into 5 groups, each of 18. The first group was considered as a control (T1) and was fed ad- libitum on the control diet. The other four groups (T2, T3, T4 & T5) were fed on diets containing poultry by-product meal at levels of 25, 50, 75 & 100 % respectively. The experiment was extended for 10 weeks. There were no significant (P<0.05) differences, in the values of body weight, body weight gain; specific growth rate, feed intake and feed conversion ratio between control, T2 and T3, while there were significant differences (P<0.05) between the control, T4 and T5. The apparent digestibility are matching with growth performance results and nutrient utilization that fish meal protein in Nile tilapia diets could be substituted with poultry by-product meal protein up to 50% without adverse effect on nutrient digestibility.
INTRODUCTION
The shortage in world production of fish meal, which is the main conventional protein source coupled with its increased demand in feeds for livestock and poultry is likely to reduce the dependence on it as a single protein source in aqua feeds (El-Sayed, 1999). It is evident, on the long-run, that many developing countries will be unable to depend on fish meal as a major protein source in aqua feeds. Therefore, several attempts have been made to partially or totally replace fish meal with less expensive, locally available protein sources
Total or partial replacement of fish meal with less expensive animal protein, such as poultry by-product meal may help to reduce feed costs, although these sources may be lower in digestibility, palatability and essential amino acids (Barlow, 1997; Hertrampf and Piedad- Pascual, 2000; Emre et al., 2003; Hu et al., 2008).
The present study was carried out to investigate the possibility of using poultry by-product meal as non-conventional protein source to replace fish meal protein in the diet of tilapia.
MATERIALS & METHODS
A total of 90 apparent healthy tilapia fingerlings with an average body weight (13.75±2.62 g/fish) obtained from local hatchery. The fish were randomly divided into 5 groups each of 18 fish. The first group was fed on control diet, while 2nd , 3rd , 4th and 5th group were fed on diets where fish meal protein was replaced by poultry by-product meal at level 25, 50, 75 and 100% , respectively. Five experimental diets were formulated from commercially available ingredients. The diets were isonitrogenous (32% crude protein) and isocaloric (3000 kcal/kg digestible energy).
Performance measurements:
- Average live body weight:
- Body weight gain:
- Feed intake:
- Feed conversion ratio:
- Specific growth rate
Composition (%) of the experimental diets
*Each2.5 kg contains: Vit. A, 12000000 IU; Vit. D3, 2000000 IU; Vit. E, 10 g; Vit. k3, 2g; Vit. B1, 1g; Vit. B2, 5g; Vit. B6, 1.5 g; Vit. B12, 10g;Nicotinic acid 30g;Pantothenic acid 10g; Folic acid 1g; Biotin 50g; Iron30g; Copper 10g; Zinc 50g;Manganese 60g;Iodine 1g; Selenium 0.10g
RESULTS
Performance of fish in the experiment
*Figures in the same raw having the same superscripts are not significantly different (P<0.05).
Apparent digestibility coefficient of some nutrients
CONCLUSION
It could be concluded that fish meal protein in Nile tilapia diets could be substituted with poultry by-product meal protein up to 50% without adverse effect on growth performance and nutrient digestibility.
REFERENCES
Emre Y, Sevgili, H., Diler, I. (2003): Replacing fish meal with poultry by- product meal in practical diets for Mirror carp (Cyprinus carpio) fingerlings. Turk. J. Fish Aquat. Sci. 3: 81-85.
Mohamed, S.H., (2003):partial replacement of fish meal with different animal by-product meals in diets of Nile Tilapia(Oreochromis Niloticus). Ph.D.Thesis, faculty of agriculture, Cairo Univ.
Yang, Y.; Xie, S.; Cui, Y.; Lei, W.; Zhu, X.; Yang Y. and Yu Y. (2004): Effect of replacement of dietary fish meal by meat and bone meal and poultry by-product meal on growth and feed utilization on gibel carp, (Carassius auratus gibelio). Aquacult.Nutr., 10: 289- 294.
Hu, M.; Wang Y.; Wang Q.; Zhao M.; Xiong B.; Qian X.; Zhao Y, and Luo, Z. (2008): Replacement of fish meal by rendered animal protein ingredients with lysine and methionine supplementation to practical diets for gibel carp, Carassius auratus gibelio, Aquacult. 275: 260- 265.
