A BLACK LEGHORN WHICH TURNED 



WHITE 



F. A. E. Crew 



Air.iiial Breeding ReseareJi Department, University of Edinbitrgli, Scotland 



ON June 24th, 1921, a Black Leg- 

 horn hen was sent to this De- 

 partment by Mr. A. Backhouse, 

 of Pontefract, in response to an appeal 

 for "hens which had assumed the 

 characters of the male." She was then 

 eighteen months old, belonged to a 

 heavy laying strain and had herself a 

 very satisfactory egg-yield. During the 

 three months previous to her arrival 

 here, her comb had become progressive- 

 ly larger and more and more erect. 

 She began to crow, not lustily, nor 

 with a challenging note, but like a 

 youngster practising. Her plumage 

 was entirely black and hen-like, her 

 spurs mere buttons (5^ mm.) ; her 

 sexual behavior was that of indiffer- 

 ence : she did not behave as a cock 

 towards hens, nor as a hen towards a 

 male. The most remarkable features 

 were her large erect comb, measuring 

 1 1.6 cms. X 8 cms., and her weak 

 eft'ortful crowing, to perform which it 

 was necessary for her to fly on to some 

 high place. She did not perform any 

 of the wing-flapping actions of the 

 male when about to crow. 



As she was allowed the freedom of 

 the yard, her wing primaries were cut. 

 During August she began to moult 

 and the neck hackle, those primaries 

 which were missing when the wings 

 were clipped, and some of the fluff' 

 were replaced by feathers which were 

 mainly white but had irregular "washed- 

 out" black centres. The vascular tissue 

 of the head furnishings became more 

 and more congested. During the next 

 year she moulted steadily and each 

 feather as it was lost was replaced by 

 a still whiter one, until at the time 

 of her death in October, 1922, she 

 was a white bird with a few irregular 

 splashes of vestigial black. It was 



noted that the primaries which were 

 clipped were not moulted until a year 

 had passed. A few of the neck-hackle 

 and saddle-hackle feathers were defi- 

 nitely cock-like in appearance and 

 structure. During the later months of 

 her life she became progressively more 

 cjuiet, ceasing to crow and seeking 

 solitude. 



Postmortem examination showed that 

 she had died from internal haemor- 

 rhage. Occupying the situation of the 

 ovary was a large tumor the surface 

 of which was invested by a mesh of 

 dilated tortuous veins, one of which 

 had ruptured. The tumor, weighing 

 103.4 grammes, measured 7.5 x 6.3 

 cms. and was blood colored. On one 

 surface an area of what seemed to be 

 ovarian tissue was found, the rest of 

 the tumor had the form of a solid 

 fleshy mass. The oviduct was as small 

 as that of a resting bird. 



On section, the ovarian portion of 

 the tumor proved to be completely 

 atrophic, no trace of germinal tissue 

 could be found and only in one section 

 could follicular remains be iden- 

 tified ; these consisted of a mass 

 of vacuolated cells encapsuled by con- 

 nective tissue and attached to the rest 

 of the ovary by a fibrous cord contain- 

 ing groups of luteal cells, and probably 

 representing an old discharged follicle. 

 With this exception the ovarian part 

 of the tumor consisted entirely of 

 connective tissue stroma, the peripheral 

 parts of which were mainly cellular, 

 whilst the inner (sex cord) region con- 

 sisted almost wholly of white fibrous 

 tissue. The interstices and folds of 

 the ovary were packed with erythro- 

 cytes derived from the haemorrhage 

 which caused the death of the bird. 

 Luteal tissue was present in the form 



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