Three experiments were conducted in this study to determine the performance of Bunaji weaner calves, yearling bulls and fattened bulls fed diets containing 0, 10, 20, 30 and 40% levels of Palm Kernel Cake (PKC) inclusion. The first experiment was conducted using thirty (30) Bunaji weaner calves (15 bulls and 15 heifer calves) with a live weight range of 85-94kg and age range of 7.5-9 months. The animals were balanced for weight and allotted to five (5) dietary treatments in a 2x5factorial arrangement laid in Completely Randomized Design. The second experiment was a growth trial conducted using 20 yearling Bunaji bulls with live weight range of 110-150kg and aged 1-1.5 years while In the third experiment, a fattening trial was conducted using 20 Bunaji bulls with a live weight range of 190-200kg and aged 2- 2.5 years. The yearling and finishing bulls were balanced for weight and allotted to five dietary treatments with four bulls per treatment in Completely Randomized Design. They were individually penned and fed diets containing graded levels of Palm Kernel Cake (PKC) and Digitaria smutsii (Wolly finger grass)hay at 2% of their body weight each. Feeding and metabolism trials were conducted for 90 and 21 days respectively for the three experiments. Blood samples were collected for PCV and biochemical parameters at the beginning, middle and end of the feeding trials. Rumen fluid were collected at 0, 3, 6 and 9hrs intervals to determine the rumen pH, rumen ammonia nitrogen and rumen total volatile fatty acid for the yearling and fattened bulls. The CP contents of the weaner diets vary between 13.88 and 18.00% while the ME ranged from 11.79 to 11.81MJ/kg DM. The crude fibre varied from 28.00 to 33.50%. The CP contents of the yearling diets varied between 14.19 and 17.75% while ME ranged from 11.79 to 11.81MJ/kg DM. The crude fibre varied from
26.36-38.77%. The CP of the fattening diets varied between 15.63 and 20.31% while ME ranged from 11.75 to 11.78MJ/kg DM. The crude fibre varied from 13.92 to 23.31%. The result of the weaner trial when effect of sex on performance was considered showed significant (P<0.05) difference in most of the parameters measured, it was higher in bull calves than heifer though FCR was more superior in heifer calves than bull calves.When the level of inclusion was considered, the result of the feeding trial showed significant (P<0.05) difference in most of the parameters measured except the initial weight. Animals on diets containing 30% PKC (0.58Kg) inclusion had the highest weight gain. Highest weight gain was obtained for bull at 30% PKC (0.65Kg) while the lowest weight gain was obtained for heifer at 0%PKC (0.38Kg). There were significant differences (P< 0.05) in all the digestible parameters measured and positive nitrogen
balance , when effect of sex and level of inclusion of PKC was considered. The PCV and biochemical parameters analysed when effect of sex, effect of PKC inclusion and combine effect of sex and PKC inclusion were considered all fall within the normal range. The economic analyses showed that cost per kg gain was highest at 0% PKC inclusion and lowest at 40% PKC. Weight gain and value of gain (VWG) was highest at 30% PKC inclusion and lowest at 0% PKC inclusion. There was positive Net Benefit (NB) and Return to Investment on feed (RIF) when sex, level of PKC inclusion and combine effect of sex and level of inclusion was considered hence it was concluded from the result of the performance, digestibility trial, blood analyses and economic analyses that PKC can be fed to weaner calves of both sexes at 30% PKC for optimum performance without any adverse effect. In the yearling trials, Average total feed intake (ATFI) ranged between 5.38-5.61Kg/day. Average daily weight gain was highest for animal on 0% PKC while those on 10, 20, 30, 40% PKC inclusion where similar (P>0.05). All the experimental bulls attained an average weight gain of between 0.66Kg to 0.75Kg. Rumen parameters were significantly (P<0.05) affected by sampling time, The result showed that Rumen pH at 0hr was highest (7.08) and lowest at 3hrs post feeding,(6.66),RAN value was similar at 0hr pre feeding (10.44 mg/100ml) and 3hr post feeding (9.93 mg/100ml) but differ at 6hr (8.25 mg/100ml) and 9hrs post feeding (8.34mg/100ml). Cost per Kg gain was similar at 0 and 20%PKC inclusion and lowest at 40% PKC. VWG were not significant (P>0.05) for bulls on 10, 20, 30 and 40% PKC inclusion. There was positive NB and RIF across treatments. The inclusion of PKC led to reduction in feed cost from N 19598 to a range of N 18761.00- N 15609.00 (about 4.27%-20% reduction in feed cost). It was therefore concluded that PKC can be included in yearling diets at 40% for optimum performance.In the fattening study, ATFI ranged between 8.67-9.11Kg as fed /day with animals on 10, 20 and 40% PKC being statistically similar (P>0.05). The result showed that Total Volatile Fatty Acid (TVFA) was highest at 9hr post feeding (28.19)but differed at 0hr (23.80), 3hrs (24.15) and 6hrs(6.92) which were similar (P>0.05). At 3hr and 9hrs post feeding RAN was similar at 0,10,30 and 40%PKC. Blood glucose was highest for animals on diets containing 10%PKC inclusion (3.50mmol/l) and lowest for those on 30% PKC (2.88mmol/l).When sampling interval was considered, PCV value was highest at the end of the experiment (33.68%) and least value was obtained at the middle of the experiment.(31.86%) . The result of the carcass evaluation showed significant (P<0.05) difference in most of the measured parameters except for value obtained for longissimus muscle. Beef % of carcass was highest for bulls fed diets containing 0%PKC inclusion, followed by those on 10, 20 and 40% PKC but differ
for bulls on 30% PKC inclusion. Dressing % was highest for bulls fed 40%PKC inclusion which was similar to those on 30%PKC; the least value was obtained for animals on 20%PKC which was similar to those on 0% and 10%PKC inclusion. There was significant (P<0.05) difference in most of the parameters measured except the initial weight which was not significant (P>0.05) across treatment. live weight gain of the bulls was lowest for the control diet (1.14Kg) which was statistically similar with those on 20% (1.16Kg) and 40% (1.18Kg) while the highest weight gain was recorded for bulls fed diet containing 10% PKC inclusion (1.33Kg) which was not significant (P>0.05) to those on 30% PKC inclusion (1.31Kg). Bulls on 30%PKC has a more superior FCR (6.52)which was similar to those on 10%PKC (6.67) while animals on 0%PKC has the least FCR
(7.57), Cost per kg gain was highest at 0% PKC inclusion and lowest a t 40% PKC. NB and VWG were similar (P>0.05) for bulls on 10 and 30%PKC inclusion. There was positive NB and RIF across treatment. The inclusion of PKC lead to reduction in feed cost from N 29389 to a range of N 28857- N 22099 (about 1.8%-24% reduction in feed cost) therefore it was concluded that PKC can be included in fattening diets at 30% for optimum performance.