Effect of Keeping Durations Prior to Processing of Bovine Blood on Its Proximate, Gross Energy and Amino Acid Compositions

The study was conducted to investigate the effect of keeping durations prior to processing of bovine blood on its proximate composition, gross energy and amino acid profile. Slaughterhouse blood used for this research was obtained from Ntak Inyang Central Abattoir located in Itu Local Government Area, Akwa Ibom State, Nigeria. The actual processing of fresh blood sample into blood meal took place at the Department of Animal Science Laboratory, University of Uyo, Annex. A Completely Randomized Design (CRD) was used. The experiment had four (4) treatments designated as (T1, T2 T3 and T4), with each differing from one another in keeping durations. Treatment1 contained blood processed after collection at 0 hour serving as the control, T2 blood was processed after 2hours, T3 blood was processed after 4 hours and T4 blood was processed after 6 hours. Blood kept for (6 hours) prior to processing was observed to have a significantly higher values (P<0.05) for crude protein (37.93%), crude fat (2.57%), crude fibre (0.25%), crude ash (7.91%), moisture (11.19%) and gross energy (2323Kcal/kg). The nitrogen free extract (NFE) values were also significantly, high (P<0.05) as the keeping durations prior to blood processing increased. Similarly, amino acid profile for both essential (EAAS) and non essential (NEAAS) revealed that T4 (6 hours) had higher values (P<0.05) than other treatments. In specific terms, tryptophan (6.92%), Leucine (6.91%) and lysine (5.12%) for essential amino acids values were observed to be high in T4 (6 hours) whereas arginine (5.98%) and glycine (4.10%) for non-essential amino acids also recorded high values. The significant variations in values of parameters (crude protein, gross energy and amino acid profile) as observed in T4 (6 hours) might be due to the processing methods used in this study as well as the high moisture content potential of the blood meal. In conclusion, bovine blood meal processed after 6 hours of keeping duration is, therefore, recommended for end-users (farmers and feed millers), followed by T3 (4 hours).