EFFECT OF CLIMATE FACTORS ON THE REPRODUCTIVE ENDOCRINOLOGY. A STUDY IN THE FEMALE PLAINS VIZCACHA, LAGOSTOMUS MAXIMUS

BERALDO PISSINIS SP, PROIETTO S; DE WINNE C; CALCAGNO J, CORSO MC, SCHMIDT AR; BECU-VILLALOBOS D; VITULLO AD; HALPERIN J; DORFMAN VB

Mar del Plata

Congreso; Reunion Anual de Sociedades de Biociencias 2022; 2022

SAIC, SAI, FAIC, SAFIS

Variations in climate factors affect reproductive conditions of species,being seasonal breeding a reproductive strategy among mammals.The South American plains vizcacha shows seasonal breeding, withtwo gestation periods per year (150-days long) and pseudo-ovulation at mid-pregnancy. The aim was to study the influence of climatefactors on the endocrinology of the female vizcacha. We developeda retrospective study using stored serum and ovaries of animals thatwere captured between 2008 and 2019. The study was focused onthe two non-pregnancy months (March, n=14; September, n=18)and on the pseudo-ovulatory period of gestation (June-July, n=32).Using Principal Components Analysis, we determined the years between 2008 and 2019 with extreme temperature, rainfall and humidity conditions. Serum luteinizing hormone (LH) was studied byRIA, progesterone (P4) and estradiol (E2) by ELISA, and the ovarydynamics was evaluated in H&E stained ovary sections. t-Test fornon-parametric values was used to determine significant differences between groups. In March, a significant decrease in P4 and E2was determined in the hottest and highest rainfall years (HHR years)compared to the coldest and least rainfall years, and that was correlated with a significant decrease in the antral follicles and accessory corpora lutea (CL) density (p