14 FORAGE CROPS IN DENMARK 



strains of roots have a feeding value proportional to their 

 contents of total solids. 



During these same years Fjord had also carried out feeding 

 experiments with milch cows. The first question to be solved 

 was one which had for several years been much discussed 

 among farmers : will an addition of a quantity of roots to the 

 normal food for cows result in a greater yield of milk, will it 

 affect the richness of the milk, and will it have any other effect 

 on the cows ? 1 



In 1884-85 some preliminary tests were made, which seemed 

 to indicate that if sufficiently large groups of cows could be 

 selected from very large herds, so that the different groups 

 were as far as possible alike in all respects, it might be possible 

 to get reliable results by working on similar lines to those 

 followed in Fjord's feeding experiments with pigs. The first 

 experiment with cows was carried out during the winter of 

 1887-88 on five large farms or estates each having a herd of 

 100 to 200 cows in milk. On three of the farms three groups 

 were formed with 12, 10 and 10 cows in each group ; on two 

 farms it was found possible to get only two groups, having 

 12 cows each on the one farm and 13 cows each on the other. 

 During a period of preparation, lasting from 3 to 5 weeks, a 

 number of cows were selected on each farm, which, if placed 

 in groups, would form groups so nearly alike in average age, 

 weight, length of time since calving, yield of milk, and percentage 

 of fat in the milk, that if fed alike they would also produce alike, 

 both as to quantity and quality of milk. During this period of 

 preparation the cows were all fed alike, and their yield of milk 

 and quality of milk were tested daily. Only cows which had 

 calved at least twice were selected. By changing the cows 

 about and leaving out unsuitable cows the groups were at last 

 finally selected for the feeding experiments. During a period 

 of transition of 10 days their food was gradually changed to 

 that which was to be given during the time of the feeding 

 trial proper, which lasted during six periods of 10 days 

 each. 



The full scheme was worked out only on the three farms 

 with three groups of cows. All three groups were to be fed with 

 1 N. J. Fjord, " 26 Beretning om Fors0g," K0benhavn, 1888. 



