Effect of Dietary Ascorbyl-2-Phosphate on Immune Function after Transport to a Feeding Facility

• Published in: Journal of dairy science 2003-02, Vol.86 (2), p.622-629
• Main Authors: Tyler, P.J., Cummins, K.A.
• Format: Article
• Language: English
• Subjects: Animal productions; Animals; ascorbic acid; Ascorbic Acid - administration & dosage; Ascorbic Acid - analogs & derivatives; Ascorbic Acid - blood; Biological and medical sciences; Body Weight; cattle; Cattle - growth & development; Cattle - immunology; Cattle - physiology; Cell Division; Cells, Cultured; Diet; Female; Fundamental and applied biological sciences. Psychology; Hydrocortisone - blood; Hydrocortisone - pharmacology; immune function; Immunity - drug effects; Immunoglobulin G - blood; Leukocytes, Mononuclear - cytology; Lymphocytes - cytology; Mitogens - pharmacology; Terrestrial animal productions; Transportation; Vertebrates; Weight Gain
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(03)73640-6

Effects of dietary ascorbyl-2-phosphate on immune function after a 210-km trip were measured in 18 Holstein heifers. After transport on d 0, 10g of ascorbyl-2-phosphate each were added to the diets of 10 heifers, whereas eight heifers were fed a control diet. Plasma cortisol concentrations increased by an average of 25.6μg/ml on d 0 following transport, but by d 7 after transport had decreased to pretransport levels. Average daily gain was lower in heifers fed ascorbyl-2-phosphate from d 28 to 49 d after transport, but did not differ over the entire study. Feeding ascorbyl-2-phosphate maintained plasma ascorbate concentrations on d 7 post-transport, which decreased in control heifers. Plasma keyhole limpet hemocyanin antibody titers were significantly higher in control heifers from d 7 to 49. Mononuclear leukocyte proliferation responses were decreased on d 0 in lymphocytes stimulated by mitogens, with pokeweed mitogen-stimulated cells showing less of a response than cells stimulated by the other mitogens. In the absence of mitogens, dietary ascorbyl-2-phosphate increased basal 3H-methyl thymidine incorporation by cultured lymphocytes. Across diets and mitogens, lymphocytes treated with cortisol showed decreased 3H-methyl thymidine incorporation. Transportation acted as a stressor, as evidenced by the increased plasma cortisol levels at d 0 immediately after transport, but immunological effects were not apparent by d 7. Feeding ascorbyl-2-phosphate maintained plasma ascorbate concentrations on d 7, but had negative effects on immune responses posttransport.