Intraembryonic avian leukosis virus subgroup C (ALV-C) inoculation producing wasting disease in ducks soon after hatching.

We have studied the pathogenic changes in Khaki Campbell ducks injected in mid embryogenesis with ALV subgroup C virus td daPR-C derived from a molecular clone. The employed duck flock was shown to be highly genetically homogeneous and was controlled for the absence of current infections. Clear symptoms of wasting disease, which appeared since one week post hatching, represented the early consequence of the virus infection.

Effects of 1,2-dibromoethane on haematopoiesis in the chick embryo.

1. Chick embryo in ovo was used to investigate the effects of 1,2-dibromoethane (DBE) on haematopoiesis at a developmental stage where the primitive erythroid cells divide and differentiate in circulation. 2.

Amyloid A amyloidosis in non-infected and avian leukosis virus-C persistently infected inbred ducks.

The breeding history of the first inbred strain of Khaki Campbell ducks is presented. The genetic homogeneity of this strain was tested on the basis of serum amyloid A (SAA) polymorphism and it was established that it harbours only the SAA allele A, which is expressed in liver, lung and bursa of Fabricius tissues. Pathogenic changes in control and avian leukosis virus-C (ALV-C) persistently infected ducks were evaluated during the period spanning 1 to 10 months after hatching.

B (MHC) antigen dependent modulation of GvH reactivity by neonatal thymectomy and alloimmunization.

Using Prague recombinant congenic lines of chickens, we found that neonatal thymectomy led either to a marked suppression (CC donors) or to a transient increase (CB donors) of GvH response against the B-F/L + B-G and B-F/L disparate congenic embryos. Similarly, preimmunization with the B (MHC) different blood led either to the suppression or increase of GvH reactivity of the CC and CB line donors depending on the antigenic difference (B-F/L + B-G, B-F/L, B-G) between the blood used for preimmunization, the immunized donor for GvH splenomegaly assay and the recipient embryos. In all cases, the suppression of GvH response of the CC line donors is accompanied with a marked increase in GvH reactivity against syngeneic and B-G 12 disparate embryos, suggesting an autoimmune state.

Prague inbred lines of chickens: a biological model for MHC research.

Evidence for further complexity of the genetic structure of chicken major histocompatibility complex (B) is reviewed, with a historical account showing mutual dependence of the development of an animal genetic model and the growth of scientific knowledge concerning the chicken MHC.

Test of prolongation of skin graft survival by blood injections provides evidence for presence of a new histocompatibility locus in the B-G region of chicken MHC.

When used for pretransplantation treatment, blood of congenic chicken lines CB and CB.R1, incompatible only in the B-G region of the major histocompatibility complex (MHC), differed in their ability to induce prolonged survival of skin grafts transferred from either of these lines onto recipients of a third congenic line, CC. Moreover, skin grafts from CB and CB.

Differences in the prolongation of skin graft survival by pretransplant blood injections in the model system of congenic lines of chickens.

The effect of pretransplant donor-specific blood injections on the survival of subsequent skin grafts was studied in the group of congenic chicken lines (CB, CC, CB.R1, CC.R1, CC.

Effect of B-G region of the MHC on skin graft survival in chickens treated by injections of whole blood.

CC (B4/B4) chickens exhibited prolonged skin graft survival when pretreated by injections of whole blood from CB.R1 (B12.r1/B12.

Syngeneic lines of chickens. VII. The lines derived from the recombinants at the B complex (MHC) of Rous sarcoma regressor and progressor inbred lines of chickens.

Based on recombinants between the B haplotypes of chickens of inbred lines CB, CC, and CB.I-B7, three new inbred lines homogeneous in transplantation and erythrocyte antigens were established by backcrossing. These newly established recombinant lines, CB.

Interstrain differences in the reactivity of normal mouse sera against erythrocyte surface antigens of inbred chicken lines.

Normal mouse sera from non-immunized individuals of different strains gave high titres of "natural" antibodies which agglutinated RBC's of different inbred lines of chickens. Normal mouse sera of A strain and its congenic lines agglutinated RBC's of all chicken lines whereas normal sera of B10 strain and its congenic lines did not react with RBC's of Iowa A line. Normal sera of other mouse strains behaved similarly.

A spontaneous chicken chimaera with serologically and morphologically different types of erythrocytes.

Among hybrids of the inbred chicken lines, cock 1357 was found to be chimaeric in red blood cells. This cock possessed three serologically distinct types of erythrocytes and two types different in shape and size.

Analysis of the alloimmune properties of a recombinant genotype in the major histocompatibility complex of the chicken.

In a population of (CB X CC)F1 X WB hybrids, a chicken was found with a presumably recombinant haplotype, BR1, whose antigenic products detectable by hemagglutination contained determinants derived from both parental haplotypes, i.e. B1 (from CB) and B2 (from CC).