RESUMO
The duration of meiosis and spermiogenesis was studied in the dog by following the kinetics of [3H]thymidine-labeled canine spermatocytes autoradiographically. Leptotene appears to last for at least 4.20 days, zygotene for less than a day, and pachytene for about 15.50 days. The transition from diplotene to metaphase II is extremely rapid and requires approximately a day. The duration of spermiogenesis is at least 19.60 days. Both meiosis and spermiogenesis are completed by 42.15 days.
Assuntos
Cães/fisiologia , Meiose , Espermatogênese , Animais , Anuros , Columbidae , Cricetinae , Peixes , Cavalos , Humanos , Masculino , Camundongos , Especificidade da Espécie , Fatores de TempoRESUMO
The duration of individual stages of meiosis and spermiogenesis in Colisa fasciata (Bloch and Schneider) was calculated autoradiographically by following the kinetics of H3-TdR labelled spermatocytes in vivo. The leptotene lasts for less than 0.5 day, zygotene even for shorter period and pachytene for 1.86 +/- 0.13 days. The transition from diplotene to anaphase II requires about a day. The spermiogenesis is completed within 6.43 days. The labelled spermatozoa were detected at 9.68 d post injection, which is the approximate total duration of meiosis and spermiogenesis.
Assuntos
Peixes/fisiologia , Espermatogênese , Animais , Autorradiografia , Masculino , Meiose , Espermatozoides/citologia , Fatores de TempoRESUMO
Effects of single subcutaneous injection (1.5 mg/100 g body weight) of cadmium chloride were studied in the ovary, oviduct, thyroid and adrenal gland of Indian koel (Eudynamys scolopacea). Treatment resulted the significant decrease (p less than 0.001) in the weight of ovary and oviduct. The stromal tissue showed hyperaemia and profused haemorrhage leading to some cellular destruction. A marked degeneration was noticed in the lamina propria of magnum. No remarkable change occured in thyroid histology. An increment of alkaline phosphatase activity was pronounced in ovarian tissue as well as in magnum after the injection. An overall reduction of periodic acid Schiff reaction was noticed in both ovary and oviduct after the salt treatment. The experiment caused a significant reduction of eponephrine content (p less than 0.001) in hypertrophied adrenal medulla. The cortical tissues, however, unaltered in their histomorphology. The loss of total amount of cholesterol (p less than 0.05) from the adrenal gland after the experimentation was recorded. It has been suggested that the augmentation of epinephrine secretion suppressed the gonadal acitivty.
