The Effect of Different Enzyme Substrates on the Performance of Broilers Fed Peeled Cassava Root Meal (Pcrm) Based Diet
Chapter One
Study Objectives
The objectives of the study are as follows:
- To evaluate the performance of broilers fed different enzyme substrates in peeled cassava root meal based
- To investigate the carcass quality of broilers fed different enzyme substrates in peeled cassava root meal based diets
- To investigate the nutrient retention of broilers fed different enzyme substrates in peeled cassava root meal based
CHAPTER TWO
LITERATURE REVIEW
Utilization of cassava in Poultry feeding
Since the early 1930s cassava has been known and used as a livestock feed substitute instead of grains for poultry rations. The first large- scale commercial users and adopters of cassava as a livestock feed resource were livestock farmers of the European Economic Community (EEC). Cassava as a substitute resource in livestock feeds became fashionable first because of its relative cheapness compared with grains (especially corn) and later because of the increased demand of corn for human and other industrial uses such as in textiles, breweries and bakeries.
Several nutritional and feeding experiments on the potentials of cassava as a substitute for grain have been carried out since the time Tabayoyong (1935) first incorporated 30% and 60% levels of cassava starch extract into chicken diets. Major findings of studies by McMillan and Dudley (1941), Klein and Barlowen (1954). Vogt and Penner (1963), Vogt and Stute (1964), Vogt (1966), Barrios and Bressani (1967), Enriquez and Ross (1967), Olson et al. (1968), Gadelha et al. (1969), Rendon et al. (1969), Montilla et al. (1969), Olson et al. 1969, Montilla (1970), Maust et al. (1972), Chou and Müller (1972), Armas and Chicco (1973), Müller et al. (1974), Hutagalung et al. (1974), Phuah and Hutagalung (1974), Montilla et al. (1975), Adegbola (1977), Obiora (1978), Squibb and Wyld (1951), and Adesida (1979) may be summarized as follows:
- Cassava can be substituted as a feed ingredient for corn and/or other grains without negatively affecting poultry feed
- The nutritive content and value of cassava meal in livestock feed depends on the cassava variety used, the age of the cassava tuber, and the processing technology used in producing the cassava
- Low-HCN cassava varieties (sweet) are preferred by chickens to high- HCN cassava varieties (bitter).
- Levels of substitution of cassava for grain higher than 20% produce deleterious effects on the health of chickens and cause reduction in weight gain and feed conversion efficiency, especially after the fourth week.
- Excessively fine (powdery) nature of cassava flour influences the feed intake negatively and diminishes consumption of cassava
CHAPTER THREE
MATERIALS AND METHODS
Location
The experiment was carried out at the Poultry Unit of the Department of Animal Science Research and Teaching Farm, University of Nigeria, Nsukka.
Materials
Peeled cassava root meal (PCRM), maize, exogenous enzymes, other feed ingredients and additves used for the study were obtained from different locations within and outside Nsukka Local Government Area, Enugu State.
CHAPTER FOUR
RESULTS AND DISCUSSION
Average Daily Feed intake (ADFI) of Broilers fed Different Levels of PCRM Diets with Different Enzyme
The impact of different levels of PCRM and different enzyme substrates on the average daily feed intake (ADFI) of broilers are shown in Table 3. At both the starter and finisher stages (15-36d and 37-58d) and on cumulative basis (15-58d), there were significant (P < 0.05) PCRM level main effects. At the starter stage, chicks on diets containing 50% PCRM had higher (P < 0.05) ADFI than chicks on 0% PCRM and 75% PCRM diets. Chicks on diets containing 0% PCRM had the lowest (P > 0.05) ADFI. At the finisher stage, birds on diets containing 0% PCRM had higher (P < 0.05) ADFI than birds on 50% PCRM and 75% PCRM-based diets. However, birds on 75% PCRM had the lowest (P > 0.05) ADFI value. On cumulative basis, birds on 50% PCRM diets had the highest (P < 0.05) ADFI while bird on 75% PCRM had the lowest (P > 0.05) ADFI value.
At both starter and finisher stages (15-36d and 37-58d) and on cumulative basis, there were significant (P < 0.05) enzyme type main effects. At the starter stage, chicks on diets containing Roxazyme G had the highest (P < 0.05) ADFI while chicks on diets without enzyme supplementation had the lowest (P > 0.05) ADFI value. At the finisher stage and on cumulative basis, bird on diets supplemented with Roxazyme G had the highest (P < 0.05) ADFI while bird on diet without enzyme supplementation had the lowest (P > 0.05) ADFI.
CHAPTER FIVE
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
The experiment studied the effect of two enzyme substrates (Nutrase xyla and Roxazyme G) on the performance of broiler chicks (from 2-10 weeks) fed peeled cassava root meal (PCRM)l at the inclusion levels of 0, 50 and 75%. During the Starter and Finisher phases, weekly measurenent were kept on feed intake(g) and weight(g) from which average daily feed intake (ADFI), average daily weight gain (ADWG), feed conversion ratio (FCR) and feed cost per Kg weight gain (FC/kgWG) were computed to determined which level of peeled cassava root meal with or without enzyme substrates gave the best economic advantage. Nutrient retention trial was undertaken at the 8th week. The proximate analysis of experimental diets and droppings were carried out. Also, the gross energy value of the experimental diets as well as the excreta were assayed. The protein, ether extract, dry matter coefficients and metabolizable energy were calculated to determined the percentage nutrient retention. Carcass and edible organs evaluation were carried out. Dressed weight was calculated. Also, heart, liver and gizzard as percentage of dressed weight were computed. Nutrase xyla and Roxazyme G supplementation increased ADFI in the starter and finisher phase at all levels of PCRM inclusion (P<0.05). The effect of Nutrase xyla and Roxazyme G supplementation on FCR was positvely significant in the finisher phase (P<0.05). Roxazyme G supplementation diet at 50% PCRM had the best least cost value in terms of feed cost per kg weight gain. There was an increase in dressed weight percentage of birds fed Nutrase xyla and Roxazyme G supplemented diets at 50% PCRM (P<0.05). Nutrase xyla and Roxazyme G supplemented diets had no significant effect (P>0.05) on protein retention but had significant effect (P<0.05) on ether extract, dry matter and metabolizable energy retention. Nutrase xyla and Roxazyme G supplemented diets had no significant effect (P<0.05) on edible organs (heart, liver and gizzard).
REFERENCES
- Adegbola, A.A. (1977). Methionine as an additive to cassava based diets. In: Nestle, B. and Graham, M. (eds). Cassava as an animal feed. Proceedings of a workshop held at the University of Guelph, 18-20 April 1976. Ottawa International Development Research Center, IDRC 095C. pp. 9-17.
- Adesida, M. (1979). Least-cost rations for broilers using linear programming. PhD Thesis. University of Ibadan, Nigeria.
- Alam. M.J., M.A.R. Howlider, M.A.H. Pramanik and M.A. Haque,(2003). Effect of exogenous enzyme in diet on broiler performance. Intl. J. Poult. Sci., 2: 168-173
- Almirall, M. and E. Esteve-Gracia (1994). Rate of passage of barley diets with chromium oxide: Influence of age and poultry strain and effect of B- glucanase supplementation. Poult. Sci., 73: 1433-1440
- Angelovieova, M., J. Mendel and M. Angelovie,( 2005). Effect of enzyme addition to wheat based diets in broilers. Trakya Univ. J. Sci., 1: 29-33.
- Annison, G., (1995). Feed Enzyme- The Science, future developments and practical aspects in feed formulation. 10th Eur. Symp. on Poultry Nutr. October, 15-19, Antalya, Turkey, pp. 193-201.
- A.O.A.C. (1995). Association of Official Analytical Chemists. Official Methods of Analysis Washington D.C.
- Armas, A.B., and C.F. Chicco. (1973). Evaluación de la harina de yuca(Manihot esculenta) en raciones pare pollos de engorde. Agron. Trop. (Maracay): 23(6): 593-599
- Barrios, E.A., and R Bressani. (1967). Composición química de la ráiz y de las hojas de algunas variedades de yuca (Manihot esculenta). Turrialba 17(3):314-320.
- Bedford, M.R., (2001). Enzymes, antibiotics and intestinal microflora. Feed Mix, (9) 2, 2001.
- Bedford, M.R., (1996). Interaction between ingested feed and the digestive system in poultry. J. Appl. Poult. Res., 5: 86-95.