RESUMO
This study investigated the effects of age and FSH treatment on the ovarian response, follicular fluid (FF) biochemical composition, nuclear maturation, and molecular profile of cumulus-oocytes complexes (COCs) recovered from prepubertal gilts. Thirty-five prepubertal gilts were separated according to age [140 (n = 20) or 160 (n = 15) days], and within each age, the gilts were allotted to receive either 100 mg of FSH [treated; G140+FSH (n = 10) and G160+FSH (n = 7)] or saline solution [control; G140+control (n = 10) and G160+control (n = 8)]. Thus, four experimental groups were included in this study. In the FSH-treated gilts, the percentage of medium follicles increased (P < 0.0001) in the same proportion with which the percentage of small follicles decreased (P < 0.0001). In addition, the glucose concentration in the FF obtained from medium follicles increased (P < 0.05), while that of triglycerides decreased (P < 0.05) in the FSH-treated gilts. The FSH stimulation also improved (P < 0.05) the number of grade I COCs obtained from medium follicles and the meiotic maturation and BCB + rates. FSH treatment only upregulated (P < 0.05) HMGCR expression in immature COCs from prepubertal gilts. The metaphase II and BCB + rates, FF glucose and plasma IGF-1 levels were greater (P < 0.05) in prepubertal gilts at 160 than at 140 days of age. Age had no effect (P > 0.05) on the transcript abundance of the target genes in immature COCs. Hence, oocytes obtained from 140-day-old prepubertal gilts appeared less meiotically competent than those of 160-day-old prepubertal gilts. Our study suggests a possible strategy of using FSH treatment to improve oocyte quantity, quality, and nuclear maturation in 140 and 160-day-old prepubertal gilts.
Assuntos
Oócitos , Folículo Ovariano , Suínos , Feminino , Animais , Folículo Ovariano/fisiologia , Oócitos/fisiologia , Ovário , Sus scrofa , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/metabolismo , Expressão GênicaRESUMO
This study examined the effects of bovine oviductal fluid (bOF) obtained during the follicular or luteal phase of the estrous cycle on ram sperm kinematics, capacitation status and plasma membrane (PM) integrity at various time points during the 24-h incubation period. Fresh ram spermatozoa were selected using the swim-up technique and then incubated separately with either follicular phase (FbOF) or luteal phase (LbOF) bovine oviductal fluid added to Fert-TALP medium (positive control - POSControl) or in Fert-TALP medium without capacitating agents (negative control - NEGControl) at 38⯰C under 5% CO2. Incubation with FbOF or LbOF for 2â¯h and 4â¯h promoted an increase (Pâ¯<⯠0.05) in most of the sperm motility parameters as compared with the NEGControl group, and bOF-induced changes in sperm kinematics were similar (Pâ¯>⯠0.05) to those seen in the POSControl group. After 6 h of incubation, the stimulatory effect of FbOF or LbOF on ram sperm kinematics was no longer observed (Pâ¯>⯠0.05). Sperm PM integrity was not affected (Pâ¯>⯠0.05) by incubation in bOF-supplemented media or in absence of capacitating factors (NEGControl). Although neither FbOF nor LbOF had any effect on sperm capacitation rates, the proportion of acrosome-reacted spermatozoa was greater (P < 0.05) for bOF-containing media compared with the NEGControl group during the long incubation periods (18â¯h and 24â¯h). In conclusion, bOF from either follicular or luteal phase of the estrous cycle enhances ram sperm motility for up to 4â¯h and the rate of acrosome reaction after long (18-24â¯h) incubation periods without affecting sperm viability.
Assuntos
Reação Acrossômica/efeitos dos fármacos , Líquidos Corporais , Bovinos , Tubas Uterinas , Ovinos , Espermatozoides/efeitos dos fármacos , Animais , Células Cultivadas , Ciclo Estral/fisiologia , Feminino , Fase Folicular/fisiologia , Fase Luteal/fisiologia , Masculino , Motilidade dos EspermatozoidesRESUMO
This study assessed the effect of l-carnitine (LC) in sheep semen extenders containing or not egg yolk for cryopreservation in sheep. Two extenders (TRIS-egg yolk or the commercial optiXcell™ IMV medium) were used, totaling six groups: IMV - (0, 5 and 10â¯mM LC) and TRIS - (0, 5 and 10â¯mM LC). After the freezing-thawing process and throughout incubation at 38⯰C for up to 3â¯h, several parameters were evaluated: sperm kinetics, hypoosmotic, plasma membrane integrity, capacitation status and lipid peroxidation level. The supplementation of either 5 or 10â¯mM LC randomly affected some parameters and, overall, TRIS was superior (Pâ¯<â¯0.05) than IMV extender. In the LC-groups, IMV had greater (Pâ¯<â¯0.05) oxidative stress than TRIS. In conclusion, although LC affected isolated parameters, its supplementation in semen extender had no consistently beneficial effect on freezing-thawing ram sperm.