Efecto de la condición corporal al parto y del nivel de alimentación sobre la involución uterina, actividad ovárica, pre？ez y la expresión hipotalámica y ovárica de los receptores de leptina en vacas doble propósito

effect of body condition at calving and feeding level on uterine involution, ovarian activity, pregnancy and the hypothalamic and ovarian expression of leptin receptors in dual purpose cows abstract to evaluate the effect of body condition at calving (bcac) and different feeding levels (fl) on uterine involution (ui), ovarian activity (oa), pregnancy (pr), and hypothalamic and ovarian leptin receptor expression (lepexp) in postpartum cows, twenty seven crossbred cows (bos taurus x bos indicus) were randomly assigned in a 2 x 2 factorial design into four treatments (t): t1, low body condition (lbc; < 2.5) + low fl (lbclfl; n = 6); t2, lbc (< 2.5) + high fl (lbchfl; n = 7); t3, high bc (> 2.5) + low fl (hbclfl; n = 7) and; t4, high bc (>2.5) + high fl (hbchfl; n = 7). basal diet was made of hay from cynodon nlemfluensis (11% crude protein, cp) plus supplement (23% cp) at a 70:30 ratio. to assess uterine involution (ui), the following was considered: characteristic of uterine secretion (cus), uterine horn simmetry (uhs), cervix diameter (cd), and uterine position (up). weekly, from 15 to 45 days postpartum (dpp), the reproductive tract was evaluated by transrectal palpation, ultrasonography, and ria of plasma progesterone (p4). the oa was assessed through the ovarian follicles (of), which were classified as : c1 (≤ 5 mm), c2 (6-9 mm), c3 (≥ 10 mm); and the presence of corpora lutea (cl). the pr was verified by rectal palpation, ultrasound, and p4. metabolic changes were measured as total cholesterol (tc) and fructosamine (frts) at 3, 15, and 45 dpp. the hypotalamic and ovarian lepexp were determined by western blot from tissue samples of 8 cows slaughtered at 45 dpp. data were statistically analyzed by multivariate multiple regressions, anova for repeated measurements on time, cox？s multiple regression and a kruskal and wallis test. results show a correlation between t and c3 and between c3 and cus at 22 and 30 dpp. also, a correlation was detected between cl and cus a