A comparative analysis of Mhc DRB3 polymorphism in the American bison (Bison bison).

The degree of genetic polymorphism at the DRB3 locus in the major histocompatibility complex (Mhc) of the North American bison was investigated by PCR and DNA sequence analysis. Nine different alleles were characterized in a selected sample of 20 animals. The genetic distances between alleles were as large as usually found at highly polymorphic Mhc loci in other species.

Physical and behavioral findings in a pseudohermaphrodite American bison.

A pseudohermaphrodite American bison (Bison bison) behaved like an adult male when interacting with adult females, but like an adult female when interacting with adult males. Its chromosomes were a normal 60, XX and it had a uterus; but it had bilateral testes rather than ovaries. Skull measurements were intermediate between a bull and a cow.

Associations between genetic markers and growth and carcass traits in a paternal half-sib family of Angus cattle.

Segregation of polymorphic marker genes in a paternal half-sib family of Angus cattle was used to detect associations between genetic markers and quantitative traits. The half-sib family selected (n = 146) had a sire that was heterozygous at six polymorphic marker loci; BoLA-A (class I major histocompatibility complex), B, C and F blood group systems, serum transferrin and vitamin D binding protein. Segregation of alleles fit the expected ratios for all marker loci.

Blood groups in animals.

The membrane of RBC is literally peppered with a great variety of antigenic determinants (blood factors). Some are fixed genetically, ie, they occur on the RBC of all members of the species under study. Others segregate genetically, ie, they occur on the RBC of some but not all members of the species under study.

Acute oral median lethal dose of haloxon and coumaphos in sheep as influenced by plasma A esterase.

Determination of the acute oral medial lethal dose (LD50) of haloxon for lambs classified as to the presence or absence of plasma esterases (A esterase; EsA) rapidly hydrolyzing haloxon revealed markedly different values for the 2 phenotypes of sheep. The LD50 for EsA- lambs was 763 mg/kg of body weight with 95% confidence limits of 543 to 1,072 mg/kg. The acute oral LD50 for EsA+ lambs remains undetermined but was demonstrated to be in excess of 11,392 mg/kg.

Blood type analyses of creole-like cattle: a comparison with Longhorns and mixed controls.

Creole-like cattle blood types were compared with a mixed control group and Longhorn data using hemolytic and electrophoretic techniques. Among the hemolytic tests, the crucial B system analyses indicated that 1) the Creole-like animals were more similar to Longhorns than were the controls; 2) the three groups were different from each other; 3) the three groups were not mutually exclusive. Eleven new phenogroups were postulated.

Linkage of loci controlling alloantigens on red blood cells and lymphocytes in the horse.

A system of equine lymphocyte alloantigens designated ELA, is identified, and it is shown that the locus or loci controlling these markers must be closely linked to the locus controlling markers in the A system of horse blood groups. Among 29 offspring in two stallion families there was evidence for one recombinant. Lod scores for linkage between the A and ELA loci in the two families were 3.

Subtypic linearity in the bovine B blood group system.

The technique of proteolytic digestion employing the enzymes trypsin, chymotrypsin, and protease was used to investigate the physical order of subtypic determinants occurring on bovine erythrocytes. In the B system subgroup Y1, Y2, the determinants behaved as if linearly arranged in the same order as predicted from their serological behavior; furthermore, the differences between the two subtypes appeared to be quantitative rather than qualitative. In the E'1, E'2, E'3 subgroup, however, the subtypic determinants did not appear to be physically linear, although they are serologically linear.

Leukemia allotransplants in canine fetuses: influence of host age and immune responsiveness.

Myelomonocytic leukemia cells allografted prenatally in some developing purebred Beagle fetuses elicited tumors postnatally in some of the pups. The later in gestation that the inoculum was delivered, the less was the disposition to eventual leukemia, indicating that fetal host age at the time of grafting and tumorigenesis are correlated. The leukemogenic transplants may have grown because of fetal immunoinsufficiency or because they were tolerogenic in the developing immune system.

Use of blood typing to confirm principles of coat-color genetics in horses.

The chestnut rule in equine coat-color genetics asserts that the inter se mating of chestnut horses never produces bay, black, brown or gray offspring. The gray rule asserts that a gray offspring must have at least one gray parent. Nine alleged exceptions to the chestnut rule, all involving bay offspring, and eight alleged exceptions to the gray rule, including four offspring that were also exceptions to the chestnut rule, were examined for parent-offspring genetic incompatibilities in as many as 17 genetic systems of blood-group markers.

Equine toxoplasmosis: a survey for antibodies to Toxoplasma gondii in horses.

A nationwide sample of horses was tested to determine the prevalence of toxoplasma antibodies in equine animals. Of 1,294 serum samples from horses tested by the microtitration indirect hemagglutin test, 20% were positive. Among the popular breeds of horses, the following antibody prevalences were found: Arabian, 19%; Paint, 22%; Quarter Horses, 13%; Thoroughbred, 24%; and Standardbred, 17%.

Atropinesterase and cocainesterase of rabbit serum: localization of the enzyme activity in isozymes.

Zymograms reveal a multiplicity of esterase isozymes in rabbit serum. Most of the staining activity is concentrated in a region of the gels just anodal to the albumins where six phenotypes (A, AF, F, M, P, and S) are distinguished. The atropinesterase activity is associated with phenotypes A and AF and appears to be restricted to a single isozyme, zone A.