12 N. H. Agricultural Experiment Station [Bulletin 302 



portant effect on feed costs. Heifers not pastured until they were 12 

 months or more of age were not on the average pastured for two full 

 seasons. A heifer turned out to pasture at the age of more than one 

 year would have to freshen at the advanced age of more than three years 

 in order to utilize pasture for two entire seasons. In such cases a few 

 extra months of barn feeding beyond the age of about 2.5 years materi- 

 ally affected feed costs. The average feed costs for farms where heifers 

 were pastured at seven months or less were $8.29 per heifer less than on 

 farms where heifers were not turned out to pasture until they had at- 

 tained the age of 12 or more months. This difference was not due to 

 freshening at a younger age, but rather to less barn feeding and a great- 

 er proportion of their time being spent on pasture, a relationship which 

 follows. 



On 42 farms where the average heifers spent more than 40 per cent 

 of their total heifer days on pasture, the feed costs to the day of freshen- 



Table 6. Relation of age when first turned to pasture to feed costs of raising 

 an average heifer, and other factors. 



ing averaged approximately $12 per heifer less than for the average 

 heifers on 36 farms where 30 per cent or less of their time was spent on 

 pasture (Table 7). Feed costs for the latter group of farms were not 

 higher because heifers were kept longer before freshening, for in fact 

 they freshened on an average of 2.2 months younger, but were mainly 

 due to a proportionately small amount of time spent on pasture as a re- 

 sult of older age at time of first pasturing and a shorter pasture season. 

 Thus an increase in the per cent of total heifer days that were spent on 

 pasture was associated with an increase in the total number of pasture 

 days and in the length of pasture season, and a decline in the age at 

 first pasturing, and in feed costs. 



On 51 farms where the average heifer freshened at less than 30 months 

 of age the feed costs of raising them averaged approximately $14 less 

 than for those raised on 59 farms where they freshened at more tlian 30 

 months of age (Table 8). Although there was no significant difference 

 in the average age at which they were turned out to pasture, the former 

 group lacked on an average 44 days of utilizing two full pasture seasons. 

 Those which freshened at 30 montlis of age lacked 13 days, and those 



