Abstract #35

# 35
Metabolic profile of dairy calves supplemented with flax oil or soy oil.
C. R. Schossow*1, J. L. Anderson1, 1South Dakota State University, Brookings, SD.

Flax meal has been commercially used in the livestock industry as an alternative feeding ingredient; however, the oil extruded during milling has limited research in livestock feeding. Our objective was to investigate the effects of supplementing flax oil or soy oil in calves on metabolic profile. Thirty-six Holstein heifer calves in individual hutches were used in a 12-wk randomized complete block design study. Treatments were: 1) control (CON) with no oil, 2) 80 g/d of flax oil (FLAX), and 3) and 80 g/d of soy oil (SOY). Pre-weaning oils were fed with the milk and post-weaning they were top-dressed on starter pellets. Calves were fed 2.83 L of pasteurized milk 2 × /d during wk 1 to 5 and 1 × /d during wk 6. All calves were weaned at d 42. Pellets and water were fed ad libitum. Once weekly at 3 to 4 h post-feeding blood was collected from the jugular vein for metabolite analyses. Results were analyzed using the MIXED procedure of SAS 9.4 with repeated measures. Significant differences were declared at P < 0.05. Dry matter intakes (1792, 1487 and 1650 g/d; SEM = 79.5 for CON, FLAX, and SOY, respectively) were greater (P < 0.01) in CON than FLAX with SOY similar to both. There was a treatment × wk interaction (P < 0.01) with calves on FLAX eating less in the last 2 weeks of the study. Beta hydroxyl butyrate (BHB; 69.2, 69.5, and 67.4 mg/dL; SEM = 9.14) and plasma urea nitrogen (PUN; 11.4, 10.5, and 10.7 mg/dL; SEM 0.36) were not different among treatments. Cholesterol (36.9, 52.3, and 56.0 mg/dL; SEM = 2.29) was greater (P < 0.01) in the oil treatments compared with CON. Triglycerides (26.3, 27.0, and 32.1 mg/dL; SEM = 1.25) were greater (P < 0.01) in SOY. A tendency (P = 0.05) was observed for glucose (106.9, 105.6, and 99.9 mg/dL; SEM = 2.15) to be less in SOY. Supplementing flax oil and soy oil maintained BHB and PUN concentrations, increased cholesterol concentrations, but caused different responses compared with CON for Triglycerides and Glucose. This study demonstrates that the supplementation of plant-based oils to young calves affects their metabolic profile when compared with a diet with no oil supplementation.

Key Words: flax oil, Holstein dairy calf, metabolic profile