examination of this bull could not give any guidance for the diagnosis

of chimerism.

I thank the laboratory technicians, Mrs. I. Heinze and Mrs. E.M.
Larsen for their assistance.

The work was supported by grant from Statens almindelige Videnskabs-
fond (The Danish State Research Foundation) No. V7/66.

References

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Blom, E.: On the evaluation of bull semen with special reference to its
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tensen, Copenhagen.

Moorhead, P.S., P.C. Nowell, W.J. Mellman, D.M. Battips & D.A. Hunger-
ford: Chromosome preparations of leukocytes cultured from human

peripheral Blood. Exp. Cell Res. 1960, 20, 613-616.
Willett, E.L. & J.I. Ohms: Measurement of testicular size and its

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