Effect of Presence and Absence of Corpus Luteum on Ovarian Dimensions, Follicular Numbers and Quality of Oocytes in Iraqi Buffaloes (Bubalus Bubalis)

Abstract

This research aims to assess the presence and absence of corpus luteum (CL) on ovarian dimensions, follicular numbers, and quality of oocytes in Iraqi buffaloes (Bubalus bubalis). A total 300 numbers of ovaries of buffalo were collected from slaughterhouses of Babylon province from September 2020 until January 2021. The ovaries were assigned to have CL(n=110) and the ovaries not having CL (n = 190). Collected ovaries were evaluated for length, width, and thickness, and the follicles were calculated, measured, and classified as small (< 3 mm), medium (3-8mm), and Large (˃ 8 mm) follicles. The follicular fluid was aspirated from visible follicles (2-8mm diameter), and the oocytes were examined, counted, evaluated, and graded. The results showed that the length ( 24.20 ± 2.20 mm), width (16.80 ± 2.01 mm), and thickness (13.96 ± 1.80mm) were significantly increased (p <0.05) in ovaries bearing CL then those ovaries non – bearing CL. The average number of follicles per ovary of medium (6.58 ± 0.06) and Large (4.35 ±0.02) follicles were significantly higher (p˂ 0.05) numbers in ovaries without CL than the ovaries with CL. The significant higher were observed in good (1.86±0.12), fair (1.06±0.07) and poor (1.28 ± 0.07) oocytes in the average number of oocytes per ovary in the ovaries non - bearing CL compared with the ovaries bearing CL. In conclusion, based on these data, we can infer that the ovaries without CL included more obtainable good follicles and good quality of the oocytes than those obtained from ovaries with CL.