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Conteudo feulgen-DNA e area nuclear em espermatozoides de gado "pe-duro" (Feulgen-DNA content and nuclear area in spermatozoa of "pé-duro" cattle)^*

C.M.C. Britto^{I, II}; M.L.S. Mello^I; J.A. Cordeiro^III

^IDepartamento de Biologia Celular, Instituto de Biologica, UNICAMP, 13081 Campinas, SP, Brasil. Enviar correspondência a M.L.S.M.
^IIDepartamento de Biologia Celular, Instituto de Biologica, UNICAMP, 13081 Campinas, SP, Brasil. Enviar correspondência a M.L.S.M.
^IIIDepartamento de Estatística, IMECC, UNICAMP, 13081 Campinas, SP, Brasil

ABSTRACT

Feulgen-DNA values and nuclear areas were determined by automatic scanning microspectrophotometry for normally shaped spermatozoa of "pé-duro" bulls to investigate whether the qualities of the semen made it worthy of preservation. The levels of morphological sperm head defects in these animals was determined in a previous study. Normal Feulgen-DNA values were found in the spermatozoa of animals showing low levels of abnormally shaped sperm cells (50% of the sample). Part of these animals, however (20% of the sample), exhibited oligozoospermy. Part of the specimens from animals considered inadvisable as semen donors on the basis of morphological semen abnormalities showed Feulgen-DNA values 11.2 to 14.3% lower than the average detected for normally shaped spermatozoa. It is suggested that this phenomenon may be due to chemical changes in DNA-protein complexes in the spermatozoa and not to DNA losses through aneuploidy. The subfertility assumed for the other specimens could not be confirmed by the Feulgen reaction. This reaction thus proved to be advisable for diagnosing subfertility in "pé-duro" bulls when accompanied by results provided by other tests.

Keywords: feulgen-DNA; nuclear; spermatozoa; pé-duro; cattle.

REFERENCES

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* Parte da Tese de Mestrado de C.M.C.B. apresentada ao Instituto de Biologia da UNICAMP