Weaning age and source of energy influence beef cattle performance, carcass characteristics, and economics

creep feeding;quality;early wean

Meteer, William T. ; Faulkner ; Dan B.

关键词: creep feeding;    quality;    early wean;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/24281/Meteer_William.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Angus and Angus x Simmental calves (n=200) were randomly allotted to one of five dietary treatments at two locations: Early Wean Starch Diet (EWS), Early Wean Fiber Diet (EWF), Creep Fed Starch Diet (CFS), Creep Fed Fiber Diet (CFF), or Control (CON). Control calves were normal weaned and received no supplemental feed while they grazed with their dams. The diets fed to early-weaned and creep-fed cattle were formulated to be isonitrogenous. Early-weaned calves (133±21 days of age) were placed in the feedlot, while normal-weaned calves remained with their dams on pasture (2 or 3 replications per location). Creep feed was offered ad-libitum to CFS and CFF. After a 100 d treatment phase, calves were placed in the feedlot on a common diet. GrowSafe® was used to measure individual intake of all calves in the feedlot. In the treatment phase, early-weaned gained more than creep-fed (1.6 vs. 1.5 kg, P < 0.01), and creep-fed gained more than control calves (1.5 vs. 1.2 kg, P < 0.01). EWS had 15% lower intakes and were 13% more efficient than EWF (P < 0.01). In the finishing phase, creep-fed calves gained 9% more, had 7% lower intakes, and were 16% more efficient (P < 0.01) than early-weaned calves. CON were 5% more efficient and spent 19 more d on feed (P < 0.01) than the other treatments. Backfat was lower for the CON (1.2 vs. 1.1 cm, P = 0.02). Marbling score was higher for early-weaned cattle when compared to creep-fed cattle (586 vs. 500) and lower for the CON (476 vs. 543) than all other treatments (P < 0.01). Marbling score did not differ significantly when comparing source of energy. Economic analysis of marketing cattle as feeder calves post-treatment showed profit was 17% higher for EWF than EWS (P = 0.06), 14% higher for CFF than CFS (P = 0.06), 24% higher for creep-fed than early-weaned (P < 0.01), and 23% higher for CON than the remaining treatments (P < 0.01). Economics analysis of a retained-ownership showed profit was 31% higher for EWF than EWS (P = 0.03), 32% higher for creep-fed calves than early-weaned calves (P < 0.01), and 22% higher for CON (P < 0.01). Early weaning and creep feeding will increase carcass quality and growing phase gains, but reduce profit in this study. Co-product feeds, due to higher fat levels, could initiate marbling similar to that of starch based diets in young beef calves.