GROWTH 



407 



digestible protein to more than double that amount failed to 

 produce any greater gain but simply increased the protein 

 katabolism. That such was the case is likewise indicated by 

 the fact that the actual gains of protein per 1000 live weight 

 in these cases agree very well with those computed by the use of 

 the formula on page 378, tending to be greater rather than less. 1 

 487. Experiments with sheep. The amounts of digestible 

 protein necessary for growing sheep as formulated by Wolff in 

 his original feeding standards were based upon experiments of 

 his own 2 in which the digestibility of the feed and the gain in 

 live weight were determined. Later Weiske 3 made a series 

 of ten determinations of the nitrogen balance of two lambs at 

 ages ranging from four to twenty-four months. The rations 

 consumed were meadow hay with a decreasing proportion of 

 grain (peas) in Periods I to VII and of hay alone in the re- 

 maining periods, and the rate of increase in live weight was 

 somewhat greater than that of similar animals on pasture. The 

 following table contains the results of both investigations. 



TABLE 98. PROTEIN CONSUMED BY GROWING SHEEP 



1 The one exception to the above statement is the case animal G in Period III, 

 in which the energy content of the ration was somewhat low. 



2Landw. Jahrb., 2 (1873), 221. 3 Ibid., 9 (1880), 205. 



4 Believed by Wolff to be too low. 



