Effect of days in feedlot on growth performance, carcass and meat quality attributes of Tanzania shorthorn zebu steers
Tropical Animal Health and Production
Department of Animal Science and Production, Sokoine University of Agriculture, P.O. Box 3004, Morogoro, Tanzania; Department of Animal Science, Au Foulum, Aarhus University, Blichers Alle 20, Tjele, Denmark; Department of Larger Animal Sciences, University of Copenhagen, Frederiksberg, Denmark
A study was conducted on 50 steers (183 ± 4 kg initial body weight, 3 years of age) to assess effects of days in feedlot on performance, carcass characteristics and meat quality of Tanzania shorthorn zebu (TSZ) cattle with the aim of determining appropriate finishing period. Periods were 0 day (P<inf>0</inf>), 25 days (P<inf>25</inf>), 50 days (P<inf>50</inf>), 75 days (P<inf>75</inf>) and 100 days (P<inf>100</inf>) with 10 animals per period. Steers were housed in individual pens, fed with a concentrate diet and hay on an ad libitum basis except the P<inf>0</inf> group which was slaughtered at the beginning of trial. Long stay in feedlot, P<inf>100</inf>, increased concentrate dry matter intake by 2 kg DM/day over short stay, P<inf>25</inf>. Final weight and total gain increased (P < 0.05) from P<inf>25</inf> (22.6 kg) to P<inf>100</inf> steers (95.4 kg). Periods had no influence (P > 0.05) on an average daily gain (ADG) and feed conversion ratio (FCR) but affected carcass characteristics. Empty body weight (EBW) and hot carcass weight (HCW) increased by 61 and 65 %, respectively, from no feedlot, P<inf>0</inf> to P<inf>100</inf>. Dressing percentage was high (P < 0.05) for P<inf>100</inf> steers. Carcass measurements, internal fat, fat thickness and carcass total fat were the highest (P < 0.05) on P<inf>100</inf> steers and the lowest on P<inf>0</inf> steers. Rate of pH decline increased with days in feedlot, while cooking loss and shear force values decreased in advanced ageing time. Feedlot periods of 75 and 100 days resulted into high intake, carcass measurements and tenderness, but 100 days further increased carcass fatness and fat thickness levels, thus, with this particular feeding system and animal’s condition, 75 days is the recommended period to finish TSZ cattle in feedlots. © 2015, Springer Science+Business Media Dordrecht.
Animalia; Bos; Bos indicus; analysis; animal; animal food; animal husbandry; body weight; bovine; controlled study; diet; growth, development and aging; male; meat; physiology; randomized controlled trial; Tanzania; veterinary; Animal Feed; Animal Husbandry; Animals; Body Weight; Cattle; Diet; Male; Meat; Tanzania