Vle CONG. INTERN. REPROD. ANIM. INSEM. ARTIF, PARIS, 1968, VOL. II

Somatic Tissue Cultures. No XX metaphases were observed in the skin
or kidneys of B-85. Only two metaphases were observed in bone marrow
preparations from his sternum and both were XX. Kidney cultures on
B-60 failed to grow, but 92% of the metaphases from sternal bone
marrow were XX, the highest proportion found in any tissues of the
five bulls.

CONCLUSIONS. Five chimeric bulls were studied. Indirect evidence
for germ cell chimerism was obtained from a skewed sex ratio of
09-0Fs 7 Q in one of the bulls whose fertility was also below breed
average. Testicular degeneration was evident in the three bulls
examined; two were sterile, and the third, though fertile, produced
approximately half as many breeding units as the breed average.
Additional performance records are esseptial for evaluating the
fifth chimeric bull.

(1) S. OHNO et al., 1962. Cytogenetics l: 258-265.
(2) W. H. STONE et al., 1960. J. Heredity 51: 136-140.
(3) R. L. TEPLITZ et al., 1967. Chromosoma 22: 202-209.

(4) H., 0. DUNN et al., 1967. Cytogenetics 6: 412-419.

(5) J. H, TJIO and J, WHANG, 1962. Stain Teehini<d7 5 FL7=20%
(6) S. OHNO, 1965. Acad. Press (J. VUNLISH D725

(7) E. P, EVANS, 1965. Cytogenetics 3: 289-294.

(8) B. H., McSPARRIN and T. E. Patrick, 19675 - J.-Dalry Scis ;502
6125

Supported in part by USPHS Grant E-3204 and USAEC C00-1210-41.
Paper No. 1235 from Laboratory of Genetics, University of Wisconsin,
Madison, Wisconsin.

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