ABSTRACT
It is suggested that normal heteroantibodies may contribute to the difficulties of species hybridization by damaging heterologous spermatozoa and/or by reducing hybrid embryonic viability.
Techniques are described for titrating yolk antibody and for agglutination tests with fowl spermatozoa.
Plasma samples from several breeds of chickens were titrated with turkey erythrocytes in order to study the variability of normal heteroagglutinin titres.
Turkey spermatozoa were agglutinated in vitro by chicken plasma. Absorption tests showed that the same antigens, reacting with the normal heteroagglutinin of chicken plasma, occur on turkey spermatozoa and turkey erythrocytes. Further work is required on the agglutination of chicken sperm by turkey plasma.
Low titres of anti-turkey-erythrocyte agglutinin in the blood of domestic hens did not promote interspecific fertility. Immunization of domestic hens with the erythrocytes of the cockerel with which they were mated did not induce infertility. It is nevertheless considered that an investigation of normal incomplete antibody in relation to inter- and intraspecific fertility might prove fruitful.
Normal heteroagglutinins occur in turkey and chicken yolk. The titre of anti-turkey agglutinin in chicken yolk is very close to that in the hen’s plasma.
Antigens reacting with the normal heteroagglutinin of turkey plasma appear on chick embryo erythrocytes after 4–5 days’ incubation; there seems to be little quantitative increase thereafter. They occur on both primitive and definitive erythrocytes.
Normal anti-turkey agglutinin derived from the egg yolk was detected in the blood plasma of a few chick embryos after 13 days’ incubation or more.
The latter results are discussed in relation to other published work both on the effects of antisera on embryogenesis and on the ontogeny of antigenic properties.
