Effect of Whole Cassava Meal as Substitutes for Maize in the Diets on the Performance Characteristics and Egg Quality of Laying Hens

連絡者:Yasuhiro KAWAMOTO Senbaru 1, Nishihara-cho, Okinawa, 903-0213, Japan TEL: +81-(0)98-895-8764, Fax: +81-(0)98-895-8734 E-mail:yasuk@agr.u-vyukyu.ac. jp INTRODUCTION Cereal grains, particularly maize, normally constitute a major proportion of poultry feed as the energy source. Maize is also the main source of energy in most farm animal feeds. However, the situation is different in the developing countries where cereals, legumes and some other animal feed components constitute staple foods for man (Eruvbetine et al. 2003; Onyimonyi and Ugwu 2007). At present the scarcity of conventional protein and energy resources is largely responsible for the high price of livestock feed. In the coming years, poultry producers will definitely have to look beyond maize and other cereal grains because of their low availability and inability to keep pace with everincreasing poultry production (Chauynarong et al. 2009). The use of unconventional feed resources in poultry nutrition is one of the ways to overcome this feed crisis in the poultry industry. Alternative feed sources have proved valuable in supporting the performance of livestock and poultry at low cost of production (Babatunde and Oluyemi 2000). Cassava has been reported as a major staple food widely cultivated in the lowlands of the humid tropics and capable of providing higher amount of energy/ha, about 13 times more than maize or guinea corn (Sorghum) (Oyenuga 1961). Cassava, manioc, tapioca, or yuca (Manihot esculenta, Crantz) is a woody shrub of the Euphorbiaceae family, native to South America. Cassava is a multipurpose plant that thrives well in the tropics, it is a very good source of energy. It has a wide range of adaptability, resistance to drought and tolerance to poor soils (Tewe 1994). Cassava tuber contained very low levels of protein and was deficient in essential amino acids, fat, minerals and vitamins (Chauynarong et al. 2009). Therefore, Eruvbetine et al. (1994) reported that cassava root alone could not replace maize in layer diets without adversely affecting the performance of layers. Oruwari et al. (2003) stated that a complete substitute of maize was enabled by the addition of brewer’s yeast to cassava tuber, and increasing protein content in ratioanl feed for broiler. Therefore, cassava tuber meal might be completely replace maize in poultry diets with proper protein ABSTRACT The effects of feeding diets containing cassava meal (tuber and leaf) were investigated on feed intake, feed conversion ratio, weight gain, egg performance, egg quality and digestibility of layer during 4 weeks of feeding experiment. Thirty-six white leghorn layer were allocated into 4 groups of nine hens each. Diet I, contained no cassava meal but maize 57% of the diet and served as control. In diet II, III and IV, the proportion of maize was replaced with the cassava meal at the levels of 50% (40% tuber + 10% leaf), 75% (65% tuber + 10% leaf), and 100% (90% tuber + 10% leaf), respectively. The cassava meal diets tended to reduce dry matter digestibility. The birds were able to tolerate up to 75% of cassava meal (65% tuber + 10% leaf) after which egg production declined. Cassava meal diet did not have significant (p>0.05) dietary effects on the egg quality parameters. However, the trend of yolk color score decreased to the increase of the substitution level of cassava meal. The results demonstrated that maize (57%) in the commercial formula feed could be replaced with cassava meal up to 75% without any adverse effects on the laying performance and egg quality. Journal of Warm Regional Society of Animal Science, Japan 58(1): 19-28, 2015