Studies of grazing of crop forages by sheep

Abstract

SummaryForty-eight determinations of intake, weight and weight gain were made on sixteen young wethers free-grazing three blocks of rape in turn.The intake of units of starch equivalents was 8% higher than that calculated from Wood and Woodman (1930) feeding tables, a difference which was significant at the 2% probability level.A multiple-regression equation in the form of a functional relationship, which showed that maintenance requirements of the wethers were 20% higher and weight gain needs 300/<, lower than standard values, was derived. Both differences from standard values were very highly significan t.A second multiple-regression equation in which a constant term was included gave a more accurate prediction of intake of individual wethers than either standard values or the first equation.Significant correlation coefficients were found between intake and weight gain, intake and weight, and weight gain and weight.Rate of weight gain increased as grazing progressed, there being a linear increase in intake in successive blocks. This was significant at the 1 % level of probability, as also were the large and consistent differences between sheep in the level of intake.