Cassava Utilization in Kilifi and Taita Taveta Counties and Effects of Inclusion of Processed Cassava Peels in Broiler Diets on Performance

Abstract

The unprecedented increase in demand for conventional feedstuffs like wheat, sorghum and maize, for human consumption and production of animal feeds has led to the increase in their prices resulting in higher cost of foods of animal origin. This has necessitated the need for research on alternative and non-competitive feed resources to either partially or totally replace the grains that are main energy sources in broiler diets. The potential of cassava peels in Kenya has not been fully exploited partly due to fear of cyanide poisoning and the knowledge gap on various processing methods to reduce toxicity. The objective of this study was to document the use of cassava and cassava byproducts as livestock feed in 2 counties in Kenya and to assess the effect of inclusion of treated cassava peel meal in broiler chicken diets on performance. In the first study, data was collected on the availability of cassava and its by-products and their usage as animal feed in Kilifi and Taita Taveta counties through a semi-structured questionnaire. Results indicated that 69.6% of the respondents in both Counties grew cassava majorly for household consumption of the tubers with the rest being sold to generate income. Cassava leaves (68%) were the major cassava plant part fed to cattle. The majority of the respondents (86.6%) fed the peels to the livestock immediately after the peeling without any processing. In the second study, the effect of the inclusion of sun-dried cassava peel meal (SCPM) and Aspergillus Oryzae fermented (FCPM) cassava peel meal in broiler diets on performance, diet digestibility, carcass characteristics and cost-benefit were determined. The diets were formulated to contain 0% CPM, 5% (SC5), 10% (SC10) and 15% (SC15) sun dried Cassava Peel Meal (CPM) and 5% (FC5), 10% (FC10) and 15% (FC15) fermented CPM respectively. Two hundred and ten (210) Cobb 500 day old broiler chicks were purchased from a commercial hatchery, acclimatized for five days and then randomly housed in 21 metallic cages (10 birds in each cage) and put into xiv the seven dietary treatments (30 birds per treatment) for 42 days. The birds were fed on both starter and finisher rations formulated to be iso-caloric and iso-nitrogenous. On day 42 of the feeding trial, three birds were randomly selected from each replicate, fasted overnight and sacrificed for the determination carcass characteristics. At the conclusion of the feeding period (42 days), four birds were randomly selected for each of the seven diets and placed in metabolic cages for determination of apparent digestibility of the diets using the total collection method. The daily feed intake (DFI) decreased with increasing FCPM in the diet from 126.8g/d in FC5 to 114.8g/d in FC15 but increasing with increased SCPM in the diet (from 121g/d in SC5 to 125g/d in SC15) compared with the control (125.2g/d). The daily body weight gain (BWG) increased with the increased inclusion of fermented cassava peel meal (FCPM) with birds on 15% FCPM having a significantly higher BWG (64.72g/d) compared to other treatments. The feed conversion ratio (FCR) decreased with increase inclusion of the fermented peels with birds on 15% FCPM having the lowest (P<0.05) FCR (1.77). The carcass characteristics; dressing weight, meat colour and pH of thighs, breast and drumstick were not affected by treatment. The apparent digestibility of DM was not affected by treatment while that of CF decreased with increased inclusion of SCPM in the diets from 36.74% for control to 33.02% for SC15 but increased with the increase of the FCPM in the diets from 36.83% for FC5 to 39.98% for FC15 treatment. The gross profit margin varied from 277.3 in SC15 to 326.6 Ksh/bird in FC15 treatment while the return on investment (RoI) varied from 95.2 in SC15 to 115.2Ksh/bird in FC10 treatment and was significantly affected by the treatments with the control having the lowest RoI (91.8). In conclusion, the study demonstrated that A. Oryzae fermented cassava peels resulted in reduction in CF and HCN, higher CP and could be included up to 15% in broiler rations resulting in better BWG, DFI and FCR and reduced cost of BWG.