|Carroll, Jeffery - Jeff Carroll|
Submitted to: Journal of Animal Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 2/28/2012
Publication Date: 6/25/2012
Citation: Cribbs, J.C., Young, T.R., Jennings, M.A., Sanchez, N.C., Carroll, J.A., Callaway, T.R., Schmidt, T.B., Johnson, B.J. 2012. Dried citrus pulp alters feedlot performance of crossbred heifers during the receiving period [abstract]. Journal of Animal Science. 90:377(E-Suppl. 3). Interpretive Summary:
Technical Abstract: A study was designed to determine the effect of feeding dried citrus pulp pellets (CP) on feedlot performance of newly-received English x Continental heifers. Heifers (n=180) were sourced in two loads (188.7+/-18.0 kg and 225.2+/-22.2 kg, respectively) from commercial auction barns and placed on trial at the Texas Tech University Beef Center in New Deal, Texas. A completely randomized block design was used by blocking by BW nested within arrival load with three treatment diets being applied (36 pens; 5 heifers/pen; 12 blocks; 3 pens/block; 12 pens/treatment). Treatment diets were formulated to contain: 1) 0% CP on a dry matter basis; 2) 10% CP on a dry matter basis; or 3) 20% CP on a dry matter basis. Diets containing CP were formulated to be exchanged with steam flaked corn on a 1:1 basis. Cattle were fed a 63, 73, and 83% concentrate diet from days 0 to 28, days 28 to 42, and days 42 to 56, respectively. From day 0 to 28, there was a linear decrease in dry matter intake (DMI; P<0.0001) which resulted in a linear decrease in average daily gain (ADG; P<0.0001) and Gain:Feed (G:F; P<0.01) as the proportion of CP in the diet increased. From day 28 to d 42, DMI decreased linearly (P=0.02) as the proportion of CP in the diet increased; however, no difference in ADG was observed and G:F increased linearly (P<0.01) in favor of treatments with a higher proportion of CP. From day 42 to d 56, DMI did not differ across treatments, but ADG (P=0.02) and G:F (P=0.04) decreased linearly as the proportion of CP in the diet increased. Over the entire 56-day trial period, as the proportion of CP in the diet increased DMI decreased (P=0.02; 6.70, 6.13, and 5.96 kg for 0, 10, and 20% CP, respectively), ADG decreased (P<0.0001; 1.88, 1.27, and 1.00, respectively), and G:F decreased (P=0.02; 0.225, 0.210, 0.91, respectively). Collectively, it appears that regardless of the level of roughage in the diet, the inclusion of dried CP pellets at levels of 10% or greater deters DMI such that feedlot performance suffers. Future studies will need to evaluate inclusion levels of CP less than 10% or evaluate alternative processing strategies of CP to offset the negative effects of CP on intake in diets of newly-received calves.