Abstract
This study was conducted to clarify the effects of dry carrots feeding on colostral immunoglobulin (Ig) contents in 11 Japanese Black cows fed grass silage based diet. Experimental diets were control diet and control diet supplemented with dry carrots (138mg β-carotene /day), and dry carrots were offered from 3 weeks before the expecting calving day to parturition. Plasma β-carotene contents in the control and dry carrot groups at parturition were 378 and 475μg/dL, and plasma and colostral β-carotene contents were not affected by feeding dry carrots. Feeding dry carrots had no effects on IgG, IgA and IgM contents in plasma and colostrum of cows. There was a positive correlation between plasma IgM contents and colostral IgM contents in cows. Colostral IgM contents were positively correlated with colostral IgG or colostral IgA contents, and colostral IgG contents were positively correlated with colostral IgA contents.
