CHAPTER ONE
- INTRODUCTION
1.1 Background study
Recently, the nutritional status of the populace in most developing countries is predominantly marked by inadequate protein intake both in quantity and quality (Taiwo et al., 2005). Efforts are being directed towards exploring all reasonable options to meet the recommended level at a reduced cost. Poultry production is a good source of animal protein and contributes immensely in boosting the consumption level of animal protein because of its short generation interval and high growth rate (Essen et al., 2005). The exponential increase in the cost of input especially feed is among the constraints in commercial broiler production (Vivian et al., 2015). Research strategies are directed towards more net return and minimizing high cost through inclusion of feed supplements and feed additives in the diets of broiler chicken.
Broiler production is one of the most popular livestock enterprises adopted by small and medium scale farmers in both rural and urban areas as it offers the highest turnover and quicker returns on investment (Afolayan et al., 2014). The benefit of broiler production is grossly affected by the high cost of feed and an established fact that feed represents the major cost of poultry production. The feed cost could be as high as 80% of the total cost of production of the finished feed (Longe, 2006).
Since birds eat in order to satisfy their energy requirement, the implication is that the energy content of a diet would determine the extent of consumption of such feed. The energy component of a feed is usually high and a reduction in the cost of energy would translate to reduced cost of feeding livestock (Ayuk et al., 2009). Maize which is predominantly used ingredient for energy in poultry feed in Nigeria is very costly, due to high demand by humans as food and industrial purposes (Bot et al., 2013; Etuk et al., 2013). Frequently, the cost of maize has increased considerably due to competition with the human food industry, increased production of biofuel and droughts in some parts of Africa resulting to maize price increase by 71.16 % from 2005 – 2015 (USDA, 2015).
This increase in price led to increase in the price of the poultry products. These among other factors have prompted the need to explore other potential energy sources which are either not consumed by humans, not in relative high demand (Ngiki et al., 2014).One of such alternatives for replacement of maize in animal diets is the processed cassava peel (Agiang et al., 2004). Cassava peel is gaining wider acceptance as feed for livestock animal (Onyeonagu and Njoku, 2010) both for the ruminant and non-ruminant animals.
Cassava peel is a major by-product of cassava tuber roots processing industry which is the outer cover of the tuber root usually removed manually with sharp knife (Midau et al., 2011). Cassava peel in Nigeria is always discarded as waste and is usually allowed to rot, hence resulting to waste disposal problem. The relative availability and low cost of cassava peel makes it optima in animal feeding (Oladunjoye et al., 2014). The use of cassava peel is limited by anti-nutritional factors (hydrogen cyanide) and high fiber which is harmful to the monogastric (Aguihe et al., 2016; Udedibie et al., 2004) and processing cost (Iyayi et al., 2004).
Enzyme supplementation may also be useful in reducing the toxic component of cassava peel (Udoyong et al., 2010). The advent and use of commercial feed multi-enzymes in poultry feeding has opened new horizon for the use of waste for feedstuff (Alu et al., 2012; Aya et al., 2013; Ogungbesan et al., 2014). This multi-enzyme supplementation is one of the important techniques for enhancing the efficiency of feed utilization in monogastric nutrition (Midau et al., 2011; Shirmohammed and Mehhri, 2011) and also in reducing the toxic components of the cassava peel. The role of enzymes as feed additive in poultry diets is well established and has been reported to reduce viscosity of ingesta in the intestine and showed a marked improvement on the various morphological effects of feeding fibrous materials to monogastrics (Adeyemi et al., 2013).
The purpose of adding exogenous enzymes to non-ruminant feeds is to reduce the effects of the anti-nutritional factors of ingredients that are present in greater or lesser amounts in the diet. (Nunes, 2015). Enzymes increases the availability of nutrients by breaking down specific chemical structures which endogenous digestive enzymes are not capable of breaking down or break down only partially.
The digestibility of non-starch polysaccharide (NSP) rich feed ingredients like cassava peels can be improved by treatment with enzymes (Udoyond et al., 2010; Midau et al., 2011). These enzyme complexes are formulated to complement the birds’ digestive capacity by breaking down the NSPs in the high fibrous materials (Aguihe et al., 2016). Supplementation of NSP degrading enzymes may not only reduce the anti-nutritive effects of NSP, but also releases some nutrients which could be utilized by the birds (Balamurugan and Chandrasekaran, 2009). Some enzymes used over the past several years and have potential for use in the feed industry include cellulase (B-glucanase), xylases and associated enzymes, phytases, proteases, lipases, and galactosidases (Khusheeba and Sajid, 2013).
Blood is an important index of physiological and pathological changes in animals and has been used in assessing the response of body’s ability to nutritional challenges (Aguihe et al., 2012) in order to achieve high productivity and good health knowledge of the haematological and biochemical parameters of the animal is very important.
Haematological and biochemical of the blood values could serve as an index used in assessing the body’s ability to respond to blood changes and also in predicting the effect of any given diet to animals and its constituents will reflect the physiological responsiveness of the animal to its internal and external environments which include feeds and feeding (Esonu et al., 2001).
1.2 Aims
This study is aimed at evaluating the effect of enzyme supplemented soaked cassava peal meal replacing maize on the haematology of broiler chicken.
1.3 Objectives
The objective of this work is to determine the effect of soaked cassava peel meal supplemented with enzymes as replacement for maize on the haematology of broilers such as red blood cell, white blood cell, packed cell volume, haemoglobin, neutrophils, lymphocytes, monocytes, mean cell volume, mean cell haemoglobin, and mean cell haemoglobin concentration.
