Implants for Feedlot Bulls
نویسندگان
چکیده
Ninety-six bulls, one-third each being Charolais (614lb), Hereford (600 lb) and Hereford-Angus crossbreds (566Ib) were implanted with (1) nothing, (2) Compudose, (3) Synovex or (4) Ralgro. The latter two groups were reimplanted on day 75. Bulls were placed in 12 pens and were fed a high concentrate diet for 118 days. Impants increased liveweight gains by a mean of 34 pounds (6.2 percent) and carcass weights by 17 pounds. Feed intake was increased with Compudose and Synovex implants. Feed efficiencies by implant type adjusted to a dressing percentage of62 percent were 4.85,4.85,5.14 and 4.64, indicating that intake, not utilization of energy, was the primary change induced by implants. Bulls with Ralgro implants appeared to have less internal and external carcass fat. Though all implants increased gain, only Ralgro improved efficiency of feed use by feedlot bulls. Liveweight daily gains and feed efficiencies by breed type were 3.74, 3.86 and 3.64 pounds per day and 5.24, 5.27 and 5.34, respectively. Herefords consumed about .85 pounds (5 percent) more feed per day than Charolais and crossbred bulls. Charolais bulls had less internal and external fat and larger rib eye areas than other breeds.
منابع مشابه
Testis function and feedlot performance of bulls actively immunized against gonadotropin-releasing hormone: effect of implants containing progesterone and estradiol benzoate.
The effect of implants containing anabolic steroid (Synovex) on testis function, feedlot performance, and carcass traits was evaluated in bulls, steers, and bulls actively immunized against gonadotropin-releasing hormone (GnRH). Ninety-one Hereford or Hereford x Red Angus bull calves were randomly assigned to a 3 x 2 factorial experiment. The treatments were: 1) unimmunized control (n = 30), 2)...
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A total of 144 male crossbred calves were allocated to four management treatments (bulls; steers; bulls implanted with zeranol at 100 d of age and re-implanted at 69, 93 and 56 d thereafter; bulls implanted with zeranol at 168 d of age and re-implanted at 93 and 56 d thereafter), and two pre-slaughter shipping treatments (minimum pre-slaughter stress with cattle shipped and slaughtered within 4...
متن کاملPregnancy status and feedlot performance of beef heifers actively immunized against gonadotropin-releasing hormone.
The contraceptive effect of active immunization against GnRH was evaluated in beef heifers. Crossbred heifers were randomized by breed and weight (initial weight = 227.3 +/- 1.2 kg) and assigned to one of three treatment groups. Animals in Group IB (n = 48) were actively immunized against GnRH; heifers in Groups NB (n = 48) and NN (n = 49) did not receive the anti-GnRH vaccine. Sixteen weeks af...
متن کاملPhysiology and Endocrinology
The efficacy of active immunization against GnRH as a non-invasive alternative to physical castration was assessed in Hereford × Angus bull calves. Calves were randomly assigned to 1 of 4 treatment groups; unimmunized calves (n = 8), bull calves actively immunized against GnRH (n = 30), or calves castrated at 3 months of age and either non-implanted (n = 9) or implanted with Synovex (n = 9). Im...
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