Feeding Experiment with Lactating Cows 



Experimental Procedure 



This phase of the evahiation of citrus pulp was carried out on a privately 

 owned herd of purebred Guernsey cattle. The purpose was to see if dried 

 citrus pulp could be used successfully to replace half of the grain. The herd 

 was managed and fed in the customary manner except for the use of 

 citrus pulp. Early-cut grass hay and grass silage were fed during the 

 winter months and high quality pasture during the summer months. A 

 commercial grain mixture containing 16 percent crude protein was fed 

 at a rate of 1 lb. for each 3^2 lb. milk during most of the year, but the 

 ratio was widened some when the cows were on pasture. A record was 

 kept of milk production, grain, and citrus i)ulp consumption and breeding 

 dates. The body weight of each cow. estimated by means of a tape, and a 

 condition rating were determined at monthly intervals. 



This study was divided into two parts. The first part was a reversal 

 experiment which was carried out with six pairs of cows. These animals 

 were paired as well as possible on the basis of freshening date, age, and 

 previous production rate. Beginning at parturition one member of each 

 pair was fed in the usual manner. The other member of the pair was 

 given dried citrus pulp as the concentrate at one feeding and the same 

 weight of the usual grain mixture at the other. Thirty days after parturi- 



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g 30 



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O GRAIN 



X CITRUS PULP an<i GRAIN 



30 DAY LACTATION PERIODS AFTER PARTURITION 



Figure 1. Average daily milk production (4 percent basis) by 30-day periods 

 for cows on grain and citrus and grain. 



