To assess the impact of acute caloric shortage on reproduction, rabbit does were either fed ad libitum (control, AL), or fasted for 24 (STF) or 48 h (LTF) before induction of ovulation with GnRH injection. Blood samples were collected during the last 3 h of fasting, and the following 4 h after GnRH injection, when feed was provided again, to measure plasma concentrations of LH, estradiol-17β, leptin, insulin, T3, corticosterone, glucose, and NEFA. Before re-feeding, plasma leptin, insulin, and T3 concentrations were lower (P ≤ 0.01) in both fasted groups than in controls, but then gradually increased following realimentation to match those of controls. During fasting, corticosterone levels were higher (P ≤ 0.01) in LTF than in STF and AL does, but decreased to control values soon after realimentation. During fasting, plasma glucose concentrations did not differ among groups, but upon re-feeding they markedly increased (P ≤ 0.01) both in STF and LTF does. NEFA levels were also more elevated (P ≤ 0.01) in fasted rabbits than in controls, and rapidly decreased (P ≤ 0.01) after re-feeding. Following GnRH injection, LH peak was lower (P ≤ 0.01) in LTF than in AL and STF does. Estradiol-17β showed higher pulse frequency and amplitude in AL than in STF and LTF does. Compared to controls, receptivity rate of STF and LTF artificially inseminated does declined respectively by −20.5% (P ≤ 0.05) and −22.7%, and fertility rate by −23.9% (P ≤ 0.05) and 21.4%, but no difference was found in ovulation rate. In summary, nutritional status of does, as modified by fasting, greatly influenced fertility, metabolic and reproductive hormones.
Titolo: | HORMONAL AND METABOLIC ADAPTATION TO FASTING: EFFECTS ON THE HYPOTHALAMIC–PITUITARY–OVARIAN AXIS AND REPRODUCTIVE PERFORMANCE OF RABBIT DOES |
Autore/i: | Brecchia G.; Bonanno A.; GALEATI, GIOVANNA; Federici C.; Maranesi M.; Gobbetti A.; Zerani M.; Boiti C. |
Autore/i Unibo: | |
Anno: | 2006 |
Rivista: | |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1016/j.domaniend.2005.09.006 |
Abstract: | To assess the impact of acute caloric shortage on reproduction, rabbit does were either fed ad libitum (control, AL), or fasted for 24 (STF) or 48 h (LTF) before induction of ovulation with GnRH injection. Blood samples were collected during the last 3 h of fasting, and the following 4 h after GnRH injection, when feed was provided again, to measure plasma concentrations of LH, estradiol-17β, leptin, insulin, T3, corticosterone, glucose, and NEFA. Before re-feeding, plasma leptin, insulin, and T3 concentrations were lower (P ≤ 0.01) in both fasted groups than in controls, but then gradually increased following realimentation to match those of controls. During fasting, corticosterone levels were higher (P ≤ 0.01) in LTF than in STF and AL does, but decreased to control values soon after realimentation. During fasting, plasma glucose concentrations did not differ among groups, but upon re-feeding they markedly increased (P ≤ 0.01) both in STF and LTF does. NEFA levels were also more elevated (P ≤ 0.01) in fasted rabbits than in controls, and rapidly decreased (P ≤ 0.01) after re-feeding. Following GnRH injection, LH peak was lower (P ≤ 0.01) in LTF than in AL and STF does. Estradiol-17β showed higher pulse frequency and amplitude in AL than in STF and LTF does. Compared to controls, receptivity rate of STF and LTF artificially inseminated does declined respectively by −20.5% (P ≤ 0.05) and −22.7%, and fertility rate by −23.9% (P ≤ 0.05) and 21.4%, but no difference was found in ovulation rate. In summary, nutritional status of does, as modified by fasting, greatly influenced fertility, metabolic and reproductive hormones. |
Data prodotto definitivo in UGOV: | 2007-01-15 13:45:22 |
Appare nelle tipologie: | 1.01 Articolo in rivista |