Broiler chicks performance on finisher diets containing different levels of reject cashew kernels.

Transcription

1 Agricultural Science Research Journal Vol. 2(4), pp , April 2012 Available online ISSN-L: International Research Journals Full Length Research Paper Broiler chicks performance on finisher diets containing different levels of reject cashew kernels. *E.O.K. Oddoye 1, K. Agyente-Badu 1 and V. Johnson 1. 1 Cocoa Research Institute of Ghana, P. O. Box 8, New Tafo-Akim, Eastern Region, Ghana. *Corresponding Author emmanuel_oddoye@yahoo.com, niiokpoti@gmail.com. Telephone: , Fax: ABSTRACT The purpose was to investigate the feeding of reject cashew kernels (RCK), as a feed ingredient in diets for four (4)-week old finishing broilers. Growth performance and carcass parameters of broilers fed diets containing 0, 50, 100 or 150 g kg -1 of RCK were investigated in a feeding trial set up as a completely randomized design with four (4) treatments replicated four (4) times and lasting 28 days. There were no significant differences (P > 0.05) among treatments in growth performance and carcass parameters. Cost of gain was, however, significantly different (P < 0.001). It was concluded that RCK could be included in broiler finisher diets up to a level of 150 g kg -1 without any deleterious effects. Future work will look at higher levels of RCK inclusion in the diets of finishing broilers and also its effects on broiler chicks and layers. Key Words: Performance, reject cashew kernel, broilers, feeding trial, carcass. INTRODUCTION Poultry diets in Ghana and most of West Africa have continued to rely on imported feed ingredients like soya bean and fishmeal as their major protein source. The foreign exchange rate (local currency : US Dollar) has continued to widen making these inputs more expensive as a result of which local poultry products have failed to compete with imported poultry in terms of price. The search for alternative, locally available feed ingredients has therefore become crucial. The development of cashew (Anacardium occidentale) as an important cash crop in Ghana has led to the local processing of cashew nuts into kernels. The process generates some kernels which are discarded because they are not suitable for sale as a result of being broken or oily, or because they are scorched during the drying process. It is estimated that up to about 30% of kernels may be lost in this manner depending on the quality of nuts. Although not suitable for sale, these reject cashew kernels (RCK) may find some use in animal feeding. Following reports by Fetuga et al., (1975) and Fanimo et al., (2004) that RCK gave good results when used in growing pig diets at a rate of 200 and 100 g kg -1, respectively, Oddoye et al, (2011) also included the material in finishing pig diets at 300 g kg -1 with excellent results. Reports by Odunsi (2002) and Ojewola et al, (2004) also indicated its usefulness in the feeding of poultry. This trial was therefore designed to investigate the feeding of RCK to finishing broilers. Materials and methods Feeds and feeding Reject cashew kernels (RCK) were bought from a cashew processing plant at Mim in the Brong Ahafo Region of Ghana and transported to the Cocoa Research Institute, Tafo (Eastern Region) where it was sun dried, bagged and stored for later use. Other feed ingredients used for the experimental diets were purchased from reputable local feed ingredient dealers. The experiment was carried out at the Bunso Sub-station of the Cocoa Research Institute of Ghana, Bunso, in the Eastern

2 Oddoye et al. 155 Table 1. Composition of experimental feeds EXPERIMENTAL DIETS INGREDIENT (g kg -1 ) 0 RCK 50 RCK 100 RCK 150 RCK Reject cashew kernel Maize Wheat bran Fishmeal Soya bean meal Synthetic Lysine Oyster shell Di calcium phosphate Common salt Vitamin/mineral mix a Mycofix b TOTALS CALCULATED ANALYSIS Metabolisable Energy (MJ Kg -1 ) Crude Protein (g Kg -1 ) Lysine (g Kg -1 ) Methionine (g Kg -1 ) Calcium (g Kg -1 ) Available Phosphorus (g kg -1 ) Cost Kg -1 (GH ) c a Vitamin/mineral mix (Vital Broiler and Chick Premix-G; 2.5 g kg -1 ) contains per kilogram of premix: vitamin A (11,000 IU); vitamin E (5 mg); folic acid (0.36 mg); calcium panthothenate (0.4 mg); vitamin B 12 (12 µg); vitamin B 6 (1.6 mg); vitamin D (2,000 IU); vitamin K (1.2 mg); niacin (1.6 mg); vitamin B 2 (2.4 mg) vitamin B 1 (0.6 mg); biotin (0.08 mg); choline chloride (24 mg); manganese (50 mg); zinc (40 mg); copper (2.8 mg); iodine (32 mg); selenium 0.16 mg); cobalt (0.4 mg); ethoxyquin and BHT b Mycofix Select 3.0 (BIOMIN GmbH, Herzogenburg, Austria) is a commercial mould fixing agent which is added to feeds at a rate of 1 Kg per 1000 Kg of feed. It binds mycotoxins in vivo preventing them from causing harm to the animals. c 1GH = 0.625USD as at January 16, Region of Ghana. Four experimental diets were formulated; a control treatment using no RCK,, and three treatments using 50, 100 or 150g kg -1 RCK (Table 1). As the level of RCK increased, the levels of other ingredients such as soya bean, wheat bran, fish and maize were adjusted to ensure that diets were iso-energetic and isonitrogenous. Diets were formulated to meet NRC (1994) minimum protein requirement of 190 g kg -1 for broiler finisher diets. Samples of RCK and all experimental diets were subjected to proximate analysis (AOAC, 2000). Calcium and phosphorous were determined using atomic absorption spectrophotometry Animals A total of 300 day-old unsexed COBB-500 broiler chicks were procured from Darko Farms and Company Limited, Kumasi, Ghana and reared for an initial period of four (4) weeks on a 230 g kg -1 crude protein broiler starter mash in a deep litter house. Thereafter, a sample of 272 birds of similar weights were selected for the 28-day experiment (i.e, from days 29 to 56) and randomly allocated to the four (4) dietary treatments. Each treatment was replicated four (4) times and each replicate had 17 birds. Replicate groups of birds were placed in separate pens in a concrete floored deep litter house, using wood shavings as litter. The upper half of the building was completed with wire mesh to ensure adequate ventilation. Birds were maintained on a 23- hour light regime. Water and feed were supplied to them ad libitum over the experimental period. Other management practices such as routine vaccination and drug administration were carried out as and when required. Any feed left over at the beginning of the next day was weighed and subtracted from that which had

3 Table 2. Chemical composition of reject cashew kernel and experimental diets RCK 0RCK 50RCK 100RCK 150RCK Dry matter (g Kg -1 ) g Kg -1 DM Organic matter Crude protein Ether extract Crude fibre NFE Calcium Phosphorus Table 3. Performance indicators of broilers fed finisher diets containing varying levels of reject cashew kernel (RCK) PARAMETER 0RCK 50RCK 100RCK 150RCK SED SIG Final weight (g) NS Feed intake (g) NS Weight gain (g) NS Average daily gain (g day -1 ) NS Feed conversion ratio NS Cost of gain (GH ) 2.84 a 2.65 ab 2.45 bc 2.31 c 0.11 *** a-d Means in the same row with common superscripts are not significantly (P > 0.05) different SED Standard error of the difference between two means SIG Level of significance; * , ** , *** been fed the previous day to determine feed intake. This was pooled for the experimental period. Final weight and weight gain were also determined. Feed conversion ratio (quantity of feed required for one kilogram of gain) was calculated as weight gain in kilograms divided by the weight of feed consumed in kilograms during the experimental period. Similarly, the cost of gain was calculated as the weight of feed consumed in kilograms multiplied by the price of feed per kilogram. Carcass analysis At the end of the experiment, two (2) birds (one male and one female) were selected from each replicate and their live weights measured after starving the birds of feed overnight to empty their crops. Birds were slaughtered and bled. After bleeding, carcasses were weighed to obtain their slaughter weight. Carcasses were then manually de-feathered after scalding in hot water for about a minute. They were then decapitated and eviscerated and weighed to obtain the dressed weight. Internal organs (liver, heart, intestine and gizzard) were blotted with filter paper and weighed separately. Isolated abdominal fat was also weighed. All carcass/organ weights were expressed as percentage proportions of live weight. Statistical analysis All data collected were subjected to analysis of variance using GENSTAT Release 9 (2007) software. Mean initial weight of broilers in every replicate was used as a covariate in the analysis of variance for final weight, average daily gain, feed intake, feed to gain ratio and cost of gain. For post-slaughter data, the data from each bird slaughtered was used in the analysis. Means that were significantly different (P < 0.05) were separated using LSD. Results The composition of experimental feeds and the results of proximate analysis are shown in Tables 1 and 2, respectively. As the level of RCK g kg -1 increased, there

4 Oddoye et al. 157 Table 4. Carcass-organ characteristics expressed as a percentage of live weight of broilers fed finisher diets containing varying levels of reject cashew meal (RCK) PARAMETER 0RCK 50RCK 100RCK 150RCK SED SIG Slaughter weight NS De-feathered weight NS Dressing NS Abdominal fat NS Intestinal weight NS Gizzard NS Liver NS Heart NS a-d Means in the same row with different superscripts are significantly (P < 0.05) different SED Standard error of the difference between two means SIG Level of significance; * , ** , *** was a reduction in the level of inclusion of maize, soya bean meal and fishmeal (Table 1). Cost of feed reduced with increasing level of RCK g kg -1 (Table 1). Means for growth and carcass parameters are shown in Tables 3 and 4, respectively. Analysis of variance revealed no significant differences (P > 0.05) between treatments with respect to all the parameters tested. There were, however, significant differences in cost of gain, with 0RCK g kg -1 being significantly different (P < 0.001) from 100RCK g kg -1 and 150RCK g kg -1 and 50RCK g kg -1 being significantly different (P < 0.001) from 150RCK g kg -1 (Table 4). Discussion The savings to be made in feed cost as a result of the reduction in the level of inclusion of maize, soya bean meal and fishmeal is worthy of note. This is, particularly, important in Africa where maize is a major staple for humans. The price of RCK as sold to us at the processing plant was GH 0.50 kg -1 (US$0.31 kg -1 ) was relatively cheap as compared to the price of other major ingredients as at the time of the experiment (maize - GH 0.80 kg -1 (US$0.50 kg -1 ), Soya bean meal - GH 1.40 kg -1 (US$0.88 kg -1 ), fishmeal - GH 1.90 kg -1 (US$1.19 kg - 1 )). Consequently, the price of feeds decreased from 0RCK g kg -1 through to 150RCK g kg -1 with increasing level of RCK, although the price of RCK is likely to increase once its feeding value becomes known. Although there is a paucity of information on the feeding of RCK to poultry and livestock, the few references found support the findings of this study. Ojewola et al, (2004) substituted reject cashew kernel meal for soya bean meal at 0, 25, 50, 75 and 100% in finishing broiler diets and reported a significant (P < 0.05) improvement in feed to gain ratio with the inclusion of reject cashew kernel meal. The cost per kilogram of diet also decreased with the inclusion of reject cashew kernel meal although this was not significant. Odunsi (2002) also fed pullets from week 12 to week 20 and then from week 21 to 30, with diets which had 0, 5, 10, 15 and 20% reject cashew kernel meal replacing part of the maize and groundnut cake in the control diets. Between weeks 12 and 20, birds on the reject cashew kernel diets had lower feed intake, better feed efficiency and lower feed costs than the control diet though not significantly different. From weeks 21-30, feed intake significantly decreased (P < 0.05) for diets containing reject cashew kernels. Hen day production, feed efficiency and egg quality values were unaffected. It must be borne in mind that the material (RCK) is only available in countries where cashew is processed. If in such countries oil seed cakes such as soybean cake/meal and rapeseed/canola meal are easily available it may negatively influence the use of reject cashew kernels. Industry has been set up to express oils such as soya, groundnut, canola and linseed with the residue being used as animal feed. Industry is yet to find a use for the oil from the cashew kernel and kernels are usually enjoyed as a salted nut snack. The results of this study indicate that where RCK is available it could be a valuable ingredient for the poultry industry. This full-fat material has the potential to reduce

5 the inclusion of maize, soya bean meal and fishmeal in poultry diets. Future work will have to look at higher inclusion levels of the material and also its inclusion in broiler starter diets and layer diets as well. Acknowledgements The assistance given by Mr. Dominic Owusu, Technical Officer, Daniel Larkai, Musah Adamu and Osumau Abdul Mumuni (National Service Personnel) in feeding, management and data collection is acknowledged. This paper, CRIG/07/2012/016/003, is published with the permission of the Executive Director, Cocoa Research Institute of Ghana. GENSTAT (2007). General Statistics. Release 7.2 DE (PC/Windows XP). Lawes Agricultural Trust, Rothamsted Experimental Station, United Kingdom. NRC (National Research Council) (1994). Nutrient requirements of poultry. Ninth Revised Edition. National Academy Press, Washington, D.C. pp Oddoye EOK, Agyente-Badu K, Anchirina V, Johnson V (2011). Effects on performance of growing pigs fed diets containing different levels of cashew nut reject meal. Bull. Anim. Hlth Prod. Afr. 59(1): Odunsi AA (2002). Effect of feeding reject cashew kernel meal on pre and early-laying performance of pullets. Arch. Zootec. 51: Ojewola GS, Okoye FC, Agbakuru I (2004). Performance value of cashew nut meal for soya bean meal in finishing broiler chickens. Int. J. Poult. Sci. 3: References AOAC (2000). Official Methods of Analysis of the Association of Official Analytical Chemists, 17 th Edition. Gaithersburg, MD. Fanimo AO, Oduguwa OO, Adewunmi TE, Lawal AI (2004). Utilization of dies containing cashew-nut rejects meal by weaner pigs. Nig. J. Anim. Prod. 31(1): Fetuga BL, Babatunde GM, Oyenuga VA (1975). The feeding stuff potential of cashew nut scraps kernel meal. Proceedings of the 1974 Conference on Animal Feeds of Tropical and Subtropical origin, Ibadan, Nigeria