The distribution of corpora lutea and ovarian follicular development in pregnant goats

SUMMARYThe main objective of the study was to determine the number of growing follicles (diameter ≥4 mm) with regards to the distribution of corpora lutea (CL) on the ovaries in pregnant goats. Growing follicles with a diameter greater than 5 mm i.e. large follicles were also recorded and analyzed. Daily ultrasonography (USG) examinations of ovaries were made in six Polish White Goats starting from the day of estrus detection (December/January) until parturition (May/June). An individual profile of follicular growth during the entire pregnancy was recorded for every goat. Three goats with CL present only on one ovary were included into group CL/0, and the three other goats with CL on both ovaries were in CL/CL group. The mean numbers of growing (52.0±11.3) and large (21.0±7.1) follicles during the entire pregnancy in group CL/0 were significantly (p≤0.05) higher than those of group CL/CL (growing follicles: 30.0±2.8, large follicles: 10.0±2.8). The mean numbers of growing (13.7±2.1) and large (4.4±0.9) follicles on the CL-bearing ovary were significantly (p≤0.01) lower than those on the CL-free ovary (growing follicles: 41.0±7.0, large follicles: 18.0±5.0). In conclusion, the distribution of CL in the ovaries affected a number of growing follicles during caprine pregnancy. The majority of growing follicles during this period was observed on the CL-free ovaries.