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T D Bunch

Publications and source records attributed to T D Bunch.

68 records · Page 4Linked to original sources
PubMed1981

Physiologic and hematologic values in Nelson desert bighorn sheep.

Physiologic and hematologic values were established for two groups of free ranging Nelson desert bighorn sheep (Ovis canadensis nelsoni). Eleven sheep (Group I) were captured with a drop net, 16 sheep (Group II) were immobilized with Etorphine introduced in projectile syringes. The mean glucose level, respiration rate and leucocyte count values for Group I sheep were more than twice those observed in Group II sheep. There were no differences between the groups in the other values. Data obtained were compared to values previously established for free ranging and captive Rocky Mountain bighorn sheep (O. c. canadensis), California bighorn sheep (O. c. californiana) and domestic sheep (O. aries).

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PubMed1979

A 14/28 dicentric Robertsonian translocation in a Holstein cow.

A new dicentric Robertsonian translocation is described in a Holstein cow. The translocation appears to have arisen spontaneously from the centric fusion of autosomal acro centrics 14 and 28 which resulted in a diploid chromosome number of 59. Behavioral and phenotypic anomalies of the affected cow are discussed.

Journal Article↗
PubMed1978

Chronic frontal sinusitis and osteolysis in desert bighorn sheep.

Chronic frontal sinusitis and osteolysis in a herd of desert bighorn sheep (Ovis canadensis nelsoni) in Zion National Park, Utah, was attributed to bacterial infection secondary to aberrant nasal bot migration. Analysis of skulls and live adult sheep (equal to 1 year old) showed that 9 to 22 animals were affected. One ram and 1 ewe were treated by trephination and irrigation. Treatment was successful for the ewe, but not for the ram. Radiography, thermography, and blood profiles were used in an attempt to find a way to diagnose sinusitis in its early stages; at this point, only thermography shows promise.

Animals↗
PubMed1977

G-band patterns of the Siberian snow sheep (Ovis nivicola) and their relationship to chromosomal evolution in sheep.

G-band patterns of the Siberian snow sheep, Ovis nivicola alleni, 2n=52, were compared with the patterns reported in 2n=54 wild Asiatic mouflon and 2n=54 North American sheep and those in domestic sheep with 2n=54, 53, and 52. The three largest pairs of biarmed autosomes displayed indistinguishable, presumably homologous, G-banding patterns in all types of sheep. The banding and morphology of the fourth pair of biarmed autosomes in O.nivicola differed from those of the three translocation variants described in domestic sheep. Wild sheep with 2n=54 may have evolved monophyletically from an ancestral 2n=58-56-54 population or polyphyletically by a series of independent, nonrandom fusions. In contrast, the fouth pair of biarmed autosomes in O.nivicola and in 2n=52 domestic sheep variants may have resulted from random fusions of different chromosomes.

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PubMed1976

Translocations of acrocentric chromosomes and their implications in the evolution of sheep (Ovis).

Cytogenetic evidence suggests that the caprids (sheep and goats) evolved from a common ancestor with a 2n=60 karyotype. Although goats (Capra) retained the primitive 2n=60 karyotype, sheep (Ovis) underwent a sequential reduction in the number of chromosomes by means of acrocentric translocation. The formation of the first metacentric autosome (M1) occurred in the aoudad (Ammotragus) and urial (O. vignei), resulting in a 2n=58 karyotype. The G-bands are homologous, which implies both genotypes arose from a common ancestor, possibly a rupicaprid. Based on G-bands, acrocentric chromosomes 1 and 7 of the 2n=60 karyotype formed the M1. The X chromosome, which is the second longest acrocentric in the 2n=60 karyotype, became the longest acrocentric in Ammotragus and Ovis (2n=58). The second pair of metacentrics to evolve, which is ranked in the M3 position of the 2n=54 karotype, resulted from the translocations of acrocentric chromosomes 4 and 14 or 15 in the 2n=60 karyotype. The M2 was the third pair of metacentrics to be formed and resulted from the translocations of acrocentric chromosomes 3 and 12 or 13 in the 2n=60 karyotype. The G-bands of all 2n=54 karyotypes are homologous, which indicates origin from a common ancestor. Evidence is presented that suggests a prezygotic selection is bringing about a reduction in diploid chromosome numbers. The possible roles of fission and fusion in the karyotypic evolution of Ovis are discussed.

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PubMedDate not supplied

Chromosome number of Severtzov's sheep (Ovis ammon severtzovi): G-banded karyotype comparisons within ovis.

Severtzov's sheep (Ovis ammon severtzovi; Nasonov 1914) has a 2n = 56 diploid chromosome number and a karyotype consisting of two pairs of biarmed and 25 pairs of acrocentric autosomes, a large acrocentric X, and a minute biarmed Y. The G-banding patterns of the largest pair of biarmed chromosomes were identical to those of the largest biarmed chromosomes in all wild and domestic sheep of the genus Ovis. The banding patterns of the second pair of biarmed chromosomes were identical to the third pair of biarmed chromosomes in all sheep of the genus Ovis with 2n = 54 and to the third largest pair of chromosomes in the 2n = 52 karyotype of the Siberian snow sheep (O. nivicola). The G-banded karyotype of Severtzov's sheep is consistent with all subspecies of argali (O. ammon spp.) that have been karyotyped. Numerical ascription of acrocentric chromosome equivalents based upon the fundamental karyotype of Ovis that gave rise to the biarmed chromosomes of severtzovi are 1 and 3, and 5 and 11 for the largest and second largest biarmed chromosomes, respectively. Based upon diploid chromosome number and G bands, Severtzov's sheep should be considered a subspecies of argali and not a urial.

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PubMedDate not supplied

Chromosome evolution of the blue sheep/bharal (Pseudois nayaur).

A male dwarf blue sheep was collected 60 km south of Batang east to the Jinsha Jiang river, and a male Subei blue sheep (Greater form) was collected from Gansu, China, representing two geographically separated blue sheep forms. Chromosome preparations were prepared from fibroblast cultures. The dwarf blue sheep has a 2n = 54 and a karyotype with three biarmed formations that resulted from acrocentric chromosome fusions (based on the 2n = 60 Capra autosomal equivalents) 14p/5q, 27p/1q, and 29p/2q from the largest to the smallest biarmed chromosome, respectively. The 14p/5q fusion is metacentric, whereas the 27p/1q and 29p/2q are submetacentric. The Subei blue sheep had a 2n = 56, with only the 27p/1q and 29p/2q biarmed chromosome fusions. The remainder of the chromosomes in both blue sheep are acrocentric; the X is the largest acrocentric chromosome and the Y is a minute biarmed chromosome. Our observation is one evidence showing that chromosome evolution within blue sheep has followed a series of centric fusions resulting in the reduction of chromosome number, which is typical of all extant genera within the tribe Caprini.

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PubMedDate not supplied

Chromosomes, hemoglobins, and transferrins of Iranian domestic sheep.

Twelve breeds of Iranian domestic sheep were cytogenetically analyzed. The diploid chromosome number of 2n = 54 is identical to that of most breeds of domestic sheep, which is comprised of 3 pairs of metacentric and 23 pairs of acrocentric autosomes. The sex chromosomes consist of a large acrocentric X and a small bi-armed Y. Hemoglobin analysis by isoelectric focusing for these 12 breeds resulted in the identification of 2 protein fractions: Hb AB and B. The A allele was observed in 7 percent of the 506 sheep sampled, in 6 of the 12 breeds, and then only in the heterozygous form. Transferrins were analyzed by starch-gel electrophoresis and comparisons made between breeds. Nine alleles, pooled frequency of occurrence in descending order, B, C, D, A, M, E, G, P, and I were identified and resulted in 19 phenotypes. Tfs A, B, C, and D were observed in all breeds, whereas I was found in 2,G in 1, M in 8, E in 6, and P in 2. Significant differences in allelic occurrence of Tfs A, B, C, and D were observed in seven breeds.

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PubMedDate not supplied

G-band patterns, hemoglobin, and transferrin types of the bharal: chromosomal evolutionary relationships with sheep and goats.

G-band patterns of the bharal (Pseudois nayaur), 2n = 54, were compared with those of wild sheep (Ovis dalli stonei), 2n = 54, and the Persian wild goat (Capra hircus), 2n = 60. Patterns of the longer segments of the biarmed chromosomes of Pseudois were similar to those of the longer biarmed segments of Ovis, whereas the shorter segments differed. Biarmed chromosomal segments had G-band homologies with specific acrocentric autosomes of Capra and were ranked as follows in descending order of relative lengths: Pseudois 1:4/13; 2:1/27 and 3:3/29; and for Ovis 1:1/5; 2:3/10 and 3:4.9. Arm ratios and relative lengths of the biarmed chromosomes were compared. The Y chromosome of Pseudois is a small biarmed chromosome that resembles those of Capra and Ovis. Hemoglobin B was observed in the bharal and was indistinguishable from Hb B of Ovis using starch-gel electrophoresis. The transferrin "zone pair" of Pseudois migrated more slowly in starch-gel electrophoresis than do any of the known transferrin types in sheep and goats. We refer to this transferrin as Pseudois Tf A. The biarmed formations of Pseudois and Ovis are discussed in relation to karyotype evolution and possible speciation.

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PubMedDate not supplied

Blood group comparisons between European mouflon sheep and north American desert bighorn sheep.

Blood group systems in true sheep (Ovis) provide an additional method by which phylogenetic relationships can be measured. Of the eight genetic systems of blood groups identified in domestic sheep, all appeared to have their homologue in European mouflons and at least six might have their equivalent in North American desert bighorns. The red cells of the European mouflon, which is believed to be ancestral to domestic sheep, cross-reacted with domestic sheep blood-group typing reagents much more strongly and extensively than did the red cells of desert bighorn sheep. It also was noted that all the Mexican desert bighorns tested were Da positive, but their blood factor was not observed in the Nelson desert bighorns sampled. This observation indicated that the two subspecies might differ from each other with respect to the D blood group system. Transferrin type D was observed in the mouflons, while Tfs D and E were in the desert bighorns. Hemoglobins B and AB were observed in the mouflons but only Hb B occurred in the desert bighorns. The systematic implications of blood group polymorphisms are discussed.

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