title: Acid-base parameters and steroid concentrations in pre-ovulatory follicles and plasma of lactating dairy cows with spontaneous and synchronized oestrus or follicular cyst.
abstract: The study aimed to compare the acid-base balance and steroid concentrations between follicular fluids (FF) of pre-ovulatory follicles derived from a spontaneous oestrus (SO), synchronized or induced oestrus (IO) and follicular cysts (CYS) and between FF and blood in dairy cows. Forty-two dairy cows were included in this study. The animals were allocated to three groups: SO (n = 23); IO (n = 11) using GnRH at day 0 and day 9 and PGF2 α at day 7; and animals with CYS (n = 10). The follicular fluids (FF) were aspirated from the cyst/pre-ovulatory follicles (∅ ≥ 15 mm) after SO and after second GnRH dose in IO by transvaginal ultrasound-guided ovum pick-up technique. Blood samples (BL) were collected in heparinized vacutainer tubes. The oxygen tension (pO2) in FF of IO was higher (p < 0.05) than in SO and CYS groups. There were negative correlations (p < 0.001, r = -0.89) between FF and blood pO2. The carbon dioxide tension (pCO2) and lactate level in FF of CYS group were higher (p < 0.05) than in SO and IO groups. There were negative correlations (p < 0.01, r = -0.73) between blood and FF pO2. Oestradiol-17β concentration in pre-ovulatory follicles and plasma of the SO group was higher (p < 0.001) than in IO and CYS groups. Progesterone concentration in pre-ovulatory follicles and plasma of the SO and IO groups was lower (p < 0.01) than in CYS group. Plasma androstenedione concentration in SO and IO groups was higher (p < 0.05) than in CYS group. In conclusion, acid-base parameters, E2 and P4 levels in the follicular fluid of both IO and CYS groups were deviated greatly from the physiological level (disturbances of intrafollicular/intracystic environment), which may affect the quality of both the oocyte and the granulosa cells.
authors.affiliation: Theriogenology Department, Faculty of Veterinary Medicine, Assiut University, Assiut, Egypt.
authors.forename: H A
authors.initials: HA
authors.lastname: Hussein
authors.forename: Z
authors.initials: Z
authors.lastname: Boryczko
authors.forename: H
authors.initials: H
authors.lastname: Bostedt
mesh_terms: D000136:Acid-Base Equilibrium; D000735:Androstenedione / Q000097:blood / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood*; D004958:Estradiol / Q000097:blood / Q000378:metabolism; D004971:Estrus / Q000502:physiology; D004973:Estrus Synchronization; D005260:Female; D005497:Follicular Cyst / Q000378:metabolism*; D007774:Lactation; D006080:Ovarian Follicle; D011374:Progesterone / Q000097:blood / Q000378:metabolism
chemical_list: D000735:Androstenedione; D011374:Progesterone; D004958:Estradiol