Animal production industry is geared towards converting cheap and available feedstuffs into a more balanced animal protein. A major constraint of the livestock industry in Nigeria is inadequate and poor quality feed. Feed alone accounts for over 75-80% of the total cost of production (Oluyemi and Roberts, 2000; Agbede and Aletor, 2003). Feed insufficiency is due to stiff competition for feedstuffs between human, industry and livestock, particularly for the fast growing and prolific monogastric species (Esonu, 1999; Tewe and Bokanga, 2001; Amaefule et al., 2004 and Iyayi and Davies, 2005).
Conventional sources of protein and energy such as groundnut cake, maize and sorghum are directly utilized by man and have become increasingly expensive. The over dependence on conventional protein and energy concentrates for feeding livestock is currently threatening the development of the industry. This has stimulated research efforts directed towards the use of non-conventional feedstuffs that are non-competitive, readily available and cheap (Akinmutimi, 2007). These can partly replace the traditional energy and protein feedstuffs in animal feed formulation. Non-conventional feedstuffs offer the best alternative in our environment for the reduction of feed cost and therefore a reduction in the cost of meat and other animal products (Dafwang et al., 2001).
Palm kernel cake (PKC) is a by-product of palm kernel oil extraction. It is one of the non-conventional feedstuffs. Palm kernel cake is a high fibre medium protein and energy source. It is cheaper than maize and other conventional feed sources. It is abundant in tropical areas of the world (Rhule, 1996). It is readily available in Nigeria and is not
normally consumed as food by man. In Nigeria, annual production is estimated to be about 785,000 metric tones (OSAN survey, 2003).
In Nigeria, groundnut cake (GNC) and soyabean meal (SBM) are the major plant protein components of poultry feed. In the last few years, groundnut production among the African countries has continued to decline and GNC became scarce and expensive (Enwere, 1998).
Reports on the analysis of PKC showed that it contains 18.5-21.3% crude protein (Aduku, 1993) and 9.07- 24.9% crude fibre (Onifade and Babatunde, 1998; Perez et al.,
2000). The metabolisable energy values reported for PKC ranged from 6.20MJkg-1 (Iyayi
and Davies, 2005) to 6.74MJkg-1 (McDonald et al, 1995). Palm kernel cake has been used both as protein and energy sources in laying hens (Olorede and Longe, 2000; Perez et al.,2000; Odunsi et al., 2002), broilers (Okon and Ogunmodede, 1996; Ezieshi and Olomu, 2004), pigs (Jegede et al., 1994; Kim et al., 2001; Ekenyem, 2002), rabbits (Daudu, 2007), sheep and goats (Devendra, 1978), fish (Wingkeong et al., 2002) and cattle (Bedingar and Degefa,1990; Onwueme and Sinha, 1991; Chin, 2007). In earlier studies, Jegede et al., (1994), Onifade and Babatunde (1998) and Hair-Bejo and Alimon (1995) recommended limited levels for pigs, poultry and sheep base on its high fibre content and poor availability of energy, protein, minerals and high copper content. However, studies by Akpodiete et al., (2006) have shown that PKC could replace up, to 60% of the protein in groundnut meal in the diet of broilers, pullet chicks and growers thereby permitting incorporation of 28-38% of PKC.
Boateng et al., (2008) observed that feeding PKC up to 40% to broilers, depressed body weight gain and feed efficiency at levels beyond 30%. Yeong and Mukherjee (1983) also observed that feeding 15 and 30% PKC to poultry without balancing the energy and other components of the diets affected feed intake. They observed that birds on lower levels of PKC (15%) had higher body weight gain and better feed to gain ratios than birds receiving rations with higher level (30%) of PKC. This suggests that reduction of the dietary energy, which accompanies PKC inclusion into poultry diets, may be a major problem in the feeding of this by-product. Poor palatability and lowered acceptability, attributable to the grittiness of such diets also resulted in consequent reduction in feed intake (Duran et al., 1990 and Hair-Bejo and Alimon, 1995).
Armas and Chicco (1977) fed 0, 15, 30 and 45% levels of PKC with or without lysine and methionine supplementation to 5-day old broiler chicks. They observed that the average weight at 4 or 6 weeks of age was less with 45% PKC diets than with other groups. They attributed the reduced performance of the birds as the levels of PKC increased in the rations to the increased level of dietary fibre, which resulted in depressed digestibility of other nutrients in the diets. It was further observed that the abdominal fat decreased significantly as the level of PKC in the diets of broiler chicks increased (Odunsi et al., 2002).
Palm kernel cake is less competitive. It is cheaper than GNC and soyabean meal. It has been worked on by many researchers and is known to have good nutrient profile. As a result, incorporating it in the diet of egg-type pullets will bring down the cost of feed which presently accounts for 60-70% of cost of production.
There is therefore the need for more studies on the possibility of using this cheap and more readily available protein source in diets of egg-type pullets.
The main objectives of this study are:-
- to evaluate the growth performance of egg-type pullets fed palm kernel cake.
- to determine the level at which PKC can be incorporated into the diets of chicks and growers.
- to evaluate the subsequent laying performance of birds previously fed PKC based diets during the growing phase.
- to investigate the cost effectiveness of using PKC in diets of chicks and growers.
- NULL HYPOTHESIS
- Growth performance of egg-type pullets will be affected when fed graded levels of PKC.
- Palm kernel cake cannot be incorporated at any level into the diets of chicks and growers.
- Subsequent laying performance of birds fed graded levels of PKC during the growing phase will be affected.
- No cost benefit is derived when PKC is incorporated in the diets of egg-type chicken.