Search Results

Summary.

Gonadal progestins from fetal, juvenile, pregnant and non-pregnant Masai giraffe (Giraffa camelopardalis) were extracted, purified by TLC and measured by GLC or by competitive protein-binding assay. Progesterone was found in fetal ovaries and in a fibrotic CL from a nearterm fetus as well as in CL from juvenile animals. In pregnant animals, luteal progesterone probably increased with the duration of gestation.

The values of 20β-hydroxyprogesterone were higher in juvenile giraffes than in the fetus or during early pregnancy. No 20β-hydroxyprogesterone was detectable in a CL from late pregnancy or a CL from a non-pregnant giraffe. The values tended to be inversely related to the progesterone levels.

Detectable levels of 17α-hydroxyprogesterone were present in the fetal ovary, juvenile CL and in one pregnant animal with an early preimplantation blastocyst. In the later stages of gestation, the hormone levels were too low to be detected by TLC.

Thus, it seems that the CL present in the ovaries of fetal and juvenile giraffes are endocrinologically active and similar in function to the CL of adult female giraffes.

Summary.

Investigations of the reproductive tracts of thirty-five female Procavia collected in the Kenya Rift Valley over a 1-year period are reported. The seasonal nature of breeding in these populations is confirmed. Parturition is followed by a period of lactation anoestrus. The appearance and internal structure of the ovary is described, together with an account of oogenesis and follicular development. Follicle and oocyte are large at the end of the first phase of growth, possibly due to the accumulation of lipid droplets in the oocyte. There was a high incidence of transuterine migration of ova in these animals. Considerable atresia of tertiary follicles during early pregnancy was noted. The ovary of Procavia shows general similarities to that of Dendrohyrax.

Summary.

The prenatal and postnatal ovaries of the giraffe were studied, using histological and ultrastructural techniques. Corpora lutea found in the ovaries of fetal and immature giraffe were not present after puberty, when a single, much larger CL was found in one of the two ovaries during pregnancy.