An Assessment of the Carcass Composition and Meat Quality of Boran Crossbred Cattle Finished Using Different Strategies
E. P. Maro *
Department of Animal, Aquaculture and Range Sciences, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania and Tanzania Livestock Research Institute (TALIRI), P. O. Box 834, Dodoma, Tanzania.
G.H. Laswai
Department of Animal, Aquaculture and Range Sciences, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania.
A.Z. Sangeda
Department of Animal, Aquaculture and Range Sciences, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania.
I. S. Selemani
Department of Animal, Aquaculture and Range Sciences, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania.
*Author to whom correspondence should be addressed.
Abstract
A study was performed to evaluate the effects of finishing practices and slaughter periods on carcass composition and quality of meat from Boran crossbred bulls. Fifty-four (54) bulls aged 2.5 - 3 years with initial body weight of 205 ± 1.89 kg were allocated to three finishing practices: sole grazing (P1), grazing with supplementation (P2) and feedlot finishing (P3). Three (3) bulls from each practice were slaughtered at 45 (S1), 60 (S2) and 75 (S3) days of finishing period, when the non-carcass components and carcass composition were assessed. The carcass pH was measured at 24- and 48-hours post-slaughter in the Longissimus thoracis et lumborum (LTL) muscle. The meat colour, cooking loss and shear force were determined after ageing portions of LTL muscle for 4, 8, 12, and 16 days. The feedlot finished bulls (P3) produced higher (P<0.05) internal fat (2.26 kg), heart-lung-liver weight (11.91 kg), carcass length (164 cm), and chest depth (42.43 cm) than those on P2 compared to their counterparts. The late slaughter period (S3) resulted in the highest (P<0.05) carcass length (155.97 cm) and chest depth (40.94 cm) compared to slaughter periods S2 (129.65 and 37.16) and S1 (133.41 and 36.77), respectively. Significant interactions between finishing practice and slaughter period were observed for carcass length, chest depth, hide weight, GIT weight (empty), tenderness, and redness colour. Lightness L* colour intensity was highest in S3 (45.96), while redness were significantly higher in P1 (10.47) than in P2 (9.83) and P3 (8.71). Bulls on P3 exhibited significantly more tender meat (shear force of 41.71 N/kg) compared to P1 (44.41 N/kg) and P2 (45.4 N/kg). In conclusion, 75 days of feedlot finishing and 12-day ageing produced acceptable tender meat and colour. Further research is needed on the influence of the current finishing strategies on consumer preferences.
Keywords: Boran crossbred, finishing practice, slaughter period, pH, tenderness, cooking loss