ABSTRACT
Two feeding trials were carried out to evaluate the growth performance, nutrient digestibility, carcass characteristics, haematological parameters, blood biochemical parameters and the economic advantage of broiler chickens fed graded levels of Roselle Seed Cake (RSC) asreplacement of two conventional protein sources. Proximate composition was done to determine the nutrient content of RSC and experimental diets. Experiment 1 contained graded levels of RSCreplacinggroundnut cake (GNC) while experiment 2contained graded levels of RSCreplacing soya bean cake (SBC). Three hundred (300) day old Ross broiler chicks were used in each experiment in a completely randomized design (CRD).The broiler chicks were assigned to five dietary treatments with three replicates each with 20 birds per replicate and 60 birds per treatment.Five isonitrogenous and isocaloricdietswere formulated for the broiler starter and finisher phases respectively of the two feeding trials. Diet 1 served as the control diet while diets 2, 3, 4 and 5 contained 8%, 16%, 24% and 32% RSC respectively. Data were collected andanalyzed using analysis of variance and the mean was separated using Dunnet. The results for the first feeding trial at starter phase showed that final body weight, total weight gain and average daily weight gain were significantly (P˂0.05) higher with birds on 16% RSC inclusion(1009.17, 954.17 and 34.08g). FCR was higher at 32% RSC inclusion(2.25). Feed cost per kg gain was better with the16% RSC group (₦157.60). At finisher phase, final weight, total weight gain and average daily weight gain were better at 8% RSC inclusion (2602.14,1597.14 and57.04g) but was not significantly different(P˂0.05) with birds on16% RSCinclusion (2571.67,1568.33 and 56.01g).Feed conversion ratio was better with the control diet (2.68) but not significantly (P˂0.05) different withthe 8% and 16% RSC groups (2.78 and 2.82) while feed cost per kg gain was significantly (P˂0.05) higher with the control diet (₦288.34). The dressing percentage wassignificantly (P˂0.05) higher with birds on 8% RSC inclusion (82.23%).Nutrient digestibility were significantly (P˂0.05) different in all parametersexcept for crude fibre. The parameters measured for blood quality showed no viii significant (P˂0.05) differences across dietary treatments except for white blood cell (WBC). The blood biochemical parameters showed no significant (P˂0.05) differences in total protein, low density lipoprotein (LDL) and creatinine. In the second feeding trial at the starter phase, birds on 24% RSC inclusionhad the highest final weight (996.67g).There were no significant (P˂0.05) differences in FCR across dietary treatment means. Feed cost per kg gain was better with birds on 32% (₦211.59) RSC but not significantly (P˂0.05) different with birds on 24% (₦219.20) RSC.At finisher phase, birds on 24% RSC had a better result in final weight, total weight gain, average daily weight gain and feed cost per kg gain (2077.78, 1231.11, 43.97g and ₦173.44). FCR was significantly (P˂0.05) better with birdson the 24% (2.45) RSC inclusion.Dressed weight was significantly (P˂0.05) higher with birds on the 24% (1600.67g) RSC but similar to the 32% (1533.33g) RSC group.Dry matter digestibility was significantly (P˂0.05) higher withbirds on the 24% (97.44) RSC group. Ether extract digestibility were not significantly (P˂0.05) different withbirds on the 24% (60.54%) and 32% (59.65%) RSC groups. There were no significant (P˂0.05) differences in crude fibre and crude protein digestibility across dietary treatment means. There were no significant (P˂0.05) differences in all the parameters measured for haematology across dietary treatment means except for the white blood cell. The blood biochemical composition showed no significant (P˂0.05) differences in total protein, high density lipoprotein, low density lipoprotein and creatinine across dietary treatments.RSC as an alternative feedstuff can replace GNC at 16% inclusion and soyabean cake at 24% in the diet of broiler chickens for improved performance, haematological and blood biochemicalof broilers. The cost of broiler production was reduced by 8.46%; 22.45% and 8.26%; 15.28% per bird both at the starter and finisher phases respectivelywith the replacement of 50% GNC and 75% SBC in the diets. Roselle seed cake can replace GNC and SBC at the broiler starter and finisher phases at 50% and 75% (16% and 24% dietary RSC) inclusion for better performance.
