Author
CAPPELLOZZA, BRUNO - Oregon State University | |
COOKE, REINALDO - Oregon State University | |
BOHNER, DAVE - Oregon State University | |
CHERIAN, GITA - Oregon State University | |
Carroll, Jeffery - Jeff Carroll |
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/10/2012 Publication Date: 5/14/2012 Citation: Cappellozza, B.I., Cooke, R.F., Bohner, D.W., Cherian, G., Carroll, J.A. 2012. Effects of camelina meal supplementation on ruminal forage degradability, performance, and physiological responses of beef cattle. Journal of Animal Science. 2011-4664. Interpretive Summary: This research represents a collaborative effort by scientists from Oregon State University and the Livestock Issues Research Unit to determine the influence of camelina meal supplemntation on ruminal, physiological, and performance responses of beef steers. Camelina meal, a by-product from the mechanical processing of the camelina seeds for oil extraction, may contain up to 20 percent oil, with the majority of the fatty acid content as polyunsaturated fatty acids. It was hypothesized that camelina meal may be a sustainable nutritional alternative to alleviate the acute phase response induced by stressful situations such as handling associated with the preconditioning and feedlot receiving periods. The results of this study indicated that feeding steers a diet supplmented with camelina meal increased circulation concentrations of polyunsaturated fatty acids, impaired forage and total dry matter intake, lessened the acute phase protein reaction elicited by neuoendocrine stress responses, and did not alter thyroid gland function. Therefore, camelina meal is a feasible feed ingredient that can be used to alleviate stress-induced inflammatory reactions and potentially promote cattle welfare and productivity in beef cattle operations. This data will be of interest to scientists working in the fields of stress physiology and immunology as well as cattle producers seeking to reduce imflammatory responses due to stressful events. Technical Abstract: Three experiments compared ruminal, physiological, and performance responses of beef steers consuming hay ad libitum and receiving grain-based supplements without (CO) or with (CAM) the inclusion of camelina meal. In Exp. 1, 9 steers fitted with ruminal cannulas received CAM (2.04 kg of DM/d; n = 5) or CO (2.20 kg of DM/d; n = 4). Steers receiving CAM had reduced (P = 0.01) total dry matter intake (DMI) and tended to have reduced (P = 0.10) forage DMI compared to CO. No treatment effects were detected (P = 0.35) for ruminal hay degradability parameters or plasma cholecystokinin concentrations. In Exp. 2, 14 steers receiving CAM (1.52 kg of DM/d; n = 7) or CO (1.65 kg of DM/d; n = 7) were assigned to a corticotropin-releasing hormone (CRH; 0.1 ug/kg of BW) and a thyrotropin-releasing hormone (TRH; 0.33 ug/kg of BW) challenge. Steers receiving CAM had greater (P < 0.05) serum concentrations of PUFA compared to CO prior to challenges. Upon CRH infusion, mean plasma haptoglobin concentrations tended (P = 0.10) to be reduced and ceruloplasmin concentrations increased at a lesser rate in CAM compared with CO (treatment x time; P < 0.01). Upon TRH infusion, no treatment effects were detected (P = 0.55) for serum thyrotropin-stimulating hormone, triiodothyronine, and thyroxine. In Exp. 3, 60 steers were allocated to 20 drylot pens. Pens were randomly assigned to receive CAM (2.04 kg of DM/steer daily; n = 10) or CO (2.20 kg of DM/steer daily; n = 10) during preconditioning (PC; d -28 to 0). On the morning of d 0, steers were transported for 24 h. Upon arrival, pens were randomly assigned to receive, in a 2 x 2 factorial arrangement, CAM or CO during feedlot receiving (FR; d 1 to 29). During PC, CAM had reduced (P < 0.01) average daily gain, forage and total DMI compared to CO. Plasma linolenic acid concentrations increased during PC for CAM, but not for CO (treatment x day; P = 0.02). During FR, steers that received CAM during PC had reduced (P < 0.01) forage and total DMI, but tended (P = 0.10) to have greater G:F compared to CO. Steers that received CAM during FR had greater (P < 0.05) mean plasma concentrations of polyunsaturated fatty acids (PUFA), and reduced mean rectal temperature and concentrations of haptoglobin and ceruloplasmin during FR compared to CO. In summary, camelina supplementation to beef steers impaired forage and total DMI, did not alter thyroid gland function, increased circulating concentrations of PUFA, and lessened the acute-phase protein reaction elicited by neuroendocrine stress responses. |