March, 1934] Agricultural Research in N. H. 25 



ing for meat purposes. A total of 18,295 birds were handled during 

 the year at a cost to the poultiymen of three cents per bird. Eight- 

 een flocks were certified up to December 1, 1933. {Miscellaneous In- 

 come) 



Adult Mortality Is Studied 



Despite the advances in breeding, adult mortality is one of the poul- 

 trymen's greatest problems. This has been on the increase during the 

 eight years of the state home egg-laying contest, rising from 12 per 

 cent in 1925-26 to 17 per cent in 1931-32. The 1932-33 figure dropped 

 back to about 14 per cent, due principally to a decrease in canna- 

 bilism, prolapsus, and pick-outs. Management practices to discourage 

 these habits were more widely adopted during the year. 



The 17 per cent mortality of a year ago alarmed poultrymen and 

 they requested help in controlling this loss. Eleven of them coop- 

 erated by bringing their dead or sick birds to the pathology laboratory 

 eveiy day or two. Examination of 368 adult birds by C. L. Martin 

 and C. A. Bottorff continued from February 1 to July 1 and revealed 

 that 87 per cent w^ere affected with ruptured egg-yolk. This is be- 

 lieved to have been caused by some type of mechanical injury and 

 recommendations issued called for careful handling of pullets at hous- 

 ing time, construction of equipment such as nests and roosts at proper 

 heights for convenience and comfort of birds, and prevention of fright. 

 No evidence yet gained proved that losses from mptured egg-yolk 

 are due to cholera or pullorum disease. {State Fund) 



Fowl Pox Is Increasing 



Fowl pox is gradually pushing north in New Hampshire, with first 

 cases reported about ten years ago. No vaccination campaign has 

 been pushed because every poultryman who vaccinated would thus 

 force his neighbors to vaccinate in self-defense. Vaccination has been 

 recommended by C. L. Martin and C. A. Bottorff only for poultrymen 

 whose flocks have had the disease in recent years, who have possible 

 sources of infection nearby, or who observe first symptoms in their 

 flocks. Approximately three times as many birds were vaccinated in 

 1932-33 as compared with 1928-29, or a total of 193,300 on 133 farms 

 last year. {State Fund) 



Pullorum Disease Controlled by Short Interval Testing 



Short interval testing for pullorum disease by standard tube agglu- 

 tination test included work on flocks varying in size from 600 to 4,500 

 birds and showed that three to eight monthly tests are necessary to 

 eradicate infection. 



These trials by C. A. Bottorff indicate that in the average flock, 

 the most economical procedure is to select a small breeding unit of 

 the best birds in the flock for short interval testing. This unit should 

 be large enough to replace the whole flock the next season by making 

 a large number of small hatches. These eggs should be used for hatch- 

 ing only if the unit has passed one or more free tests without reactors. 

 {Furnell Fund) 



