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2. Sperm production rates;Amman,1970
3. Sperm production of Holstein bulls determined from testicular sperm reserves after cannulation of rete testis or vas deferens and by daily ejaculation;Amman;J Dairy Sci,1974
4. Manual for Breeding Soundness Examination of Bulls;Ball,1983
5. Abnormal morphology of bovine spermatozoa;Barth,1989