Author
![]() |
Phillips, William |
![]() |
Coleman, Samuel |
![]() |
Riley, David |
![]() |
Chase, Chadwick - Chad |
![]() |
HOLLOWAY, J - Texas Agrilife Research |
![]() |
WARRINGTON, B - Texas Agrilife Research |
Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 9/28/2010 Publication Date: 11/15/2010 Citation: Phillips, W.A., Coleman, S.W., Riley, D.G., Chase, C.C., Holloway, J.W., Warrington, B. 2010. Intake and digestibility of low and high quality forage diets by purebred and cross-bred steers of tropically adapted breeds. Professional Animal Scientist. 1:1278-1285. Interpretive Summary: Tropically adapted Bos indicus and Bos taruus breeds are being evaluated as a means to improve the productivity of beef cow herds in the southern US. The objectives of these studies were to determine the impact of these breed types on the capacity of their off-spring to consume and digest feed of different quality. Boran-, Brahman-, Tuli-, and Gelvieh-sired steers were used in one experiment and steers with 25% Senepol, Tuli, or Brahman breeding and purebred Romosinuano steers were used in a second experiment. We concluded that previously developed concepts describing the interaction of low quality forage diets and protein supplementation is applicable to the breeds types used in this experiment. The resulting prodigy from these herds can enter existing production systems without changing management strategies. Technical Abstract: To improve the overall value of calves from the southern US cow herds, while maintaining tropical adaptation, tropically adapted Bos indicus and Bos taruus breeds are being evaluated. The objectives of these studies were to determine the impact of tropical adapted breed type on DMI and digestibility of low- (LQ) and high-quality (HQ) diets with and without CP supplementation. In Exp. 1, Boran-, Brahman-, Tuli- , and Gelvieh-sired steers were used to determine DMI and digestibility of high (HQ) and low (LQ) quality forage diets. Breed of sire had no affect (P > 0.10) on DM or N digestibility coefficients of HQ or LQ diets. Boran-sired steers had lower (P < 0.05) DMI of the LQ diet than the other breed types used. In Exp. 2, DMI of LQ diet was increased (P < 0.05) when supplemental CP was fed at 0.4% of BW. Steers with 25% Senepol or Tuli breeding had greater (P < 0.05) DMI than steers with 25% Brahman breeding or purebred Romosinuano steers. We concluded that previously developed concepts describing the interaction of low quality forage diets and protein supplementation is applicable to the breed types used in this experiment. In these experiments, alternative sources of tropical adaptation in beef cattle were explored. New tropically adapted beef breeds can be incorporated into cow herds that generate stocker calves. The resulting prodigy can enter existing production systems without changing management strategies. Key Words: Beef Breeds, intake, digestion. |