Effect of bio-digested cage layer manure and bio-digested pig manure on the carcass traits and blood profile of growing cockerels

Abstract

A total of 180  eight week old growing cockerels were used to evaluate effects of bio-digested cage layer manure (BCLM) and bio-digested pig manure (BPM) included at 0 (control), 10 and 20% in a 2 × 3 factorial design over seven weeks. Birds fed BPM achieved higher fasted live weight (1222.20 g) than those fed BCLM (1161.10 g). BPM also increased plucked weight (90.55% vs 86.68%) and dressing percentage (63.66% vs 57.94%) relative to BCLM.  Carcass cuts improved under BPM, neck and back (4.91%, 13.73 %) and thigh (10.08 %) were greater with BPM. Gizzard weight was greater with BCLM (3.04 %) than BPM (2.81 %), while small intestine weight was higher with BCLM (8.65%). Inclusion level (0, 10, 20%) had minimal effects on most carcass traits, although the interaction showed the highest dressing percentage at 20% BPM (66.97%) and the lowest at 20% BCLM (54.90%). Haematological indices remained within normal poultry reference ranges with no adverse source or level effect. Eosinophil proportion declined from 3.67% in birds on 0% inclusion to 1.17% in birds on 20% and basophils fell from 1.00% in birds on 0% inclusion to 0.00% in birds on 20% inclusion. Total serum protein and globulin increased with inclusion level, peaking at 10% (total protein 6.36 g/dL; globulin 3.09 g/dL) and declining at 20%. The results indicate that bio-digested manures can replace conventional protein sources in cockerel up to 20% without compromising health or most carcass traits, with BPM resulted in higher carcass yield under the conditions of this study.