Live Stock. 



136 



[August, 1911. 



(3) In comparison with serum from 

 blood inoculations it is of greater value 

 in the less susceptible plains animals 

 than in the highly susceptible hill 

 cattle. 



(4) That its reaction is produced 

 principally by a toxin which is rapidly 

 formed under the vital influence of the 

 peritoneal cavity. 



(5) The inoculation of very large 

 doses is not advisable in Indian cattle 

 on account of the danger of death from 

 toxaemia, the inability of the animals 

 to absorb it subcutaneously, and the 

 extreme caustic action it has upon the 

 tissues. 



(6) The method in the doses above 

 described, and which are small in com- 

 parison to the massive blood injections 

 is valuable in that a good serum is 

 produced. 



(7) Further experiments in diluting 

 the fluid or mixing with blood may 

 demonstrate improvements on the system 

 as at present practised. 



In the original, numerous charts are 

 included showing the testing of the 

 serum of animals prepared by both 

 methods, and also a beautiful coloured 

 plate showing the post-mortem appear- 

 ances of the mucous membrane of the 

 fourth stomach of a bull dead from 

 the effects of a subcutaneous inoculation 

 of peritoneal fluid. 



THE SINGLE TESTING SYSTEM 

 OP BREEDING FOR EGG 

 PRODUCTION. 



By D. P. Laurie, 



Government Poultry Expert 

 and Lecturer. 



(Prom the South Australian Department 

 of Agriculture, 1911.) 

 Poultry-breeders have long known 

 that high egg production is a matter of 

 strain, and that, individual hens are 

 heavy layers and others poor layers. It 

 has lone; been the rule among expe- 

 rienced breeders to carefully select their 

 breeding stock and mate them on 

 modern principles ; thus the well-known 

 South Australian laying strains have 

 been perfected. The high laying power 

 of the original individuals have become 

 fixed as a hereditary characteristic. 

 Breeders at an early date noticed that 

 a strain of heavy-laying fowls could be 

 built up only by breeding from selected 

 layers of marked fecundity. Guesswork 

 gave uncertain and negative results, and 

 it was long ago recognised that some 



method of measuring a hen's actual lay- 

 ing capacity was absolutely necpssary. 

 Trap-nests, as they are called, were in- 

 vented and are still in common use. 

 Briefly, they were so constructed that 

 when a hen entered them to lay, in the 

 inviting looking nest provided, she 

 mechanically locked herself in and could 

 not escape until her egg was collected 

 and marked and her identification 

 number recorded. The more modern 

 practice in South Australia is to ascer- 

 tain a pullet's egg production before she 

 is bred from. It is a bad practice to 

 breed from pullets or hens undergoing a 

 test which may prove them to be worth- 

 less as breeders. Besides, it is abun- 

 dantly proven that stock bred from 

 pullets are not equal, in constitution 

 and many other points, to stock bred 

 from second season hens. I speak here 

 of utility breeding for egg production, 

 and am not concerned with the practice 

 of exhibition poultry breeders. The 

 construction of the pens is described 

 later. My reasons for discarding trap- 

 nests are as follows : — 



1. Although there are many good 

 trap-nests, I have known of many 

 serious injuries to hens and pullets. 



2. Some hens will not enter trap- 

 nests ; others become very excited and 

 the egg production is seriously affected. 



3. The trap-nests require constant 

 supervision. It is quite wrong to leave 

 a hen confined for any length of time in 

 the small space provided. From a com- 

 mercial point ot view the cost of such 

 attention is too great. 



4. It is impossible to eliminate every 

 source of error where trap-nests are 

 used, and the records, though faithfully 

 kept, are not reliable. 



5. The poultry-owner who finds it 

 necessary to apply a test to ail his hens 

 or pullets does not rank in my esti- 

 mation as a breeder. It may happen 

 that a breeder may yard his selected 

 stock together and then trap-nest them. 



6. The cost of trap-nests, either in 

 cash or in time and labour, is more than 

 is generally estimated, and there are 

 constant repairs and renewals, ot which 

 we hear little. 



My reasons for advocating the single 

 pen system are — 



1. There is no mechanical device to 

 frighten or injure the fowl. 



2. She is well-housed and has suffi- 

 cient room for exercise. 



3. All possible errors in identification 

 are eliminated. 



