Growth, carcass characteristics, and profitability of organic versus conventional dairy beef steers

摘要

Bull calves (n = 49), born at the University of Minnesota West Central Research and Outreach Center (Morris) between March and May 2011, were used to compare growth measurements and profitability of conventional and organic dairy steers. Calves were assigned to 1 of 3 replicated groups at birth: conventional (CONV; n = 16), organic (pasture and concentrate; ORG; n = 16), or organic grass only (GRS; n = 17), and analysis of variables was on a pen basis. Breed groups of calves were Holstein (HO; n = 9); Holsteins (n = 11) maintained at 1964 breed average level; crossbreds (n = 19) including combinations of HO, Montbeliarde, and Swedish Red; and crossbreds (n = 10) including combinations of HO, Jersey, Swedish Red, and Normande. The CONV steers were fed a diet of 80% concentrate and 20% forage. The ORG steers were fed a diet of organic corn, organic corn silage, and at least 30% of their diet consisted of organic pasture during the grazing season. The GRS steers grazed pasture during the grazing season and were fed high-quality hay or hay silage during the nongrazing season. Intakes of a total mixed ration were recorded daily with herd management software. A profit function was defined to include revenues and expenses for beef value, feed intake, pasture intake, health cost, and yardage. The GRS (358.6 kg) steers had lesser total gains from birth to slaughter than ORG (429.6 kg) and CONV (534.5 kg) steers. Furthermore, the GRS (0.61 kg/d) steers had lesser average daily gain from birth compared with ORG (0.81 kg/d) and CONV (1.1 kg/d) steers. The GRS and ORG steers had smaller rib eye area (49.5 and 65.8 cm2, respectively) compared with CONV (75.4 cm2) steers. For profitability, GRS steers had 43% greater profit than CONV steers due to organic beef price premiums and lower feed costs. On the other hand, ORG steers had substantially less profit than CONV steers. The higher cost of production for the ORG steers is due to the extreme high value of organic corn. The results of the current study illustrate the economic potential of alternative strategies for growing and marketing male offspring of organic dairy cattle in the Midwest.