Cytogenetic and blood group studies of sheep/goat chimaeras.
Aggregation chimaeras were composed of quarter (or 1 cell) contributions from 4-cell blastocysts of sheep or goats, or of an 8-cell blastocyst of one species enveloped in three 8-cell blastocysts of the other. Gestation was in sheep or goat recipient females. Of the 10 living animals born, 3 were identified as interspecific chimaeras by body conformation and coat type among the 7 quarter/quarter aggregations and 1 among the 3 giant aggregates. Interspecific chimaerism was identified by cytogenetic study of umbilicus and blood lymphocytes respectively of 2 of these, one from each type of aggregate. Intraspecific sex chimaerism was found in 3 other animals; 2 were of giant aggregate origin, but the 1 of quarter/quarter origin must have acquired it by placental anastomosis with a twin conceptus. Tests using species-specific monoclonal antibodies and electrophoretic separation of haemoglobins and isoenzymes demonstrated sheep and goat erythrocytes in one giant aggregate chimaera; their relative proportions and those of the blood lymphocytes changed over a period of 31 months from approximately 60% goat and 40% sheep to more than 90% sheep. The plasma transferrins and amylases did not show similar relative changes from their predominantly goat-like character and, by implication, neither did their tissues of origin.
D000818:Animals; D001789:Blood Group Antigens / Q000235:genetics*; D002678:Chimera; D004586:Electrophoresis; D004912:Erythrocytes / Q000166:cytology / Q000201:enzymology; D005260:Female; D006041:Goats / Q000097:blood / Q000235:genetics*; D006454:Hemoglobins / Q000032:analysis; D007525:Isoelectric Focusing; D012756:Sheep / Q000097:blood / Q000235:genetics*
D001789:Blood Group Antigens; D006454:Hemoglobins