1473
Comparison of camelina meal and DDGS in the diet of replacement beef heifers
The objective of this study was to evaluate the effect of supplementing beef heifers with either cold-pressed camelina meal or dried distillers grains with solubles (DDGS) for 75-d before breeding on weight gain and pregnancy rates. Heifers (n = 110) were blocked by weight (BW = 300 ± 1.1 kg) into 5 pens per treatment and assigned to 1 of 2 dietary treatments. Heifers fed camelina meal consumed an average of 5.3 kg/d millet hay, 0.7 kg/d camelina meal and 1.3 kg/d corn, whereas heifers fed DDGS consumed an average of 5.3 kg/d millet hay, 1.1 kg/d DDGS and 0.9 kg/d corn. Average nutrient composition of diets was 9.3% CP, 52.6% NDF and 29.5% ADF for the camelina diet and 9.6% CP, 54.7% NDF and 29.3% ADF for the DDGS diet. Supplements were placed in bunks each morning and millet hay fed after supplements had been consumed. Heifers were bred following a 5-day CO-Synch + CIDR® fixed time AI protocol and transported to pasture the next day. Fourteen days later, 3 clean-up bulls were placed in the pasture for 46 d. Pregnancy was determined by transrectal ultrasonography 96 d after AI. Weight and pregnancy data were analyzed using the GLM and GLIMMIX procedures of SAS, respectively. ADG (0.45 ± 0.08 kg/d; P = 0.2) and final BW (339 ± 1.26 kg; P = 0.97) did not differ between treatments during the 75-d treatment period. Similarly, no difference (P = 0.35) was detected for BCS (5.2 ± 0.04) at breeding between treatments. We noted no differences between treatments in conception to timed AI (P = 0.57) or in total pregnancy rate (P = 0.35). Our data suggests that camelina meal has the potential to serve as a feed resource for replacement heifers with no adverse effect on weight gain or pregnancy rates.
Keywords:
beef heifers, protein supplement, reproduction