2008 Annual Meeting
(116ah) Effects of a Strategic Supplementation in the Deposition of Intramuscular and Subcutaneous Fat of Young Bulls, on a Grass Fed System Based on Tropical Grasses in Puerto Rico
Authors
Ortiz, M. - Presenter, University of Puerto Rico, Mayaguez Campus
Ortiz, G., University of Puerto Rico, Mayaguez Campus
Marrero, D., University of Puerto Rico, Mayaguez Campus
Martinez, E., University of Puerto Rico, Mayaguez Campus
Rivera, M., University of Puerto Rico, Mayaguez Campus
Casas, A., University of Puerto Rico, Mayaguez Campus
Cianzio, D., University of Puerto Rico, Mayaguez Campus
Pagan, M., University of Puerto Rico, Mayaguez Campus
The effect of a strategic supplementation (protein/energy) in the % of intramuscular fat, total trimmed fat, and subcutaneous fat thickness was determined. Weaned calves (9 months; n=48) were distributed in 3 treatments: T1 = grazing only; T2 = T1 + wheat meadlings (0.35-0.55% live weight). T3 = T1 + wheat meadlings (0.35-1.1 % live weight) + fattening ration 60 days before slaughter. Animals were slaughtered (487 Kg.; 20 months) and % of intramuscular fat, total trimmed fat, and subcutaneous fat thickness were determined. Supplementation increased the % of intramuscular fat in the muscles Longissimus dorsi (LD), Semimembranosus (SM), and Semitendinosus (ST) (P = 0.0495), and there was no interaction between treatment and muscle (P = 0.95). Only T1 was statistically diferent from T3 (P = 0.039). Treatments tended to increase total trimmed fat (P = 0.084), but there was no treatment effect of subcutaneous fat thickness (P = 0.32). Strategic supplementation increased the percentage of intramuscular fat in young bulls grazing tropical grasses without significantly increasing subcutaneous back fat.
Key words: Marbling, Strategic suplementation, Beef, Subcutaneous fat, Trimmed fat, Bovines