Superovulatory response and embryo quality in Boer does following dietary supplementation with different sources of omega-3 and omega-6 fatty acids during the breeding season.

The purpose of this study was to determine effects of various sources of omega-3 and omega-6 fatty acids on ovarian response and embryo quality in Boer does when there was a superovulation treatment regimen imposed. Pluriparous does were randomly assigned to be treated with 300 g of one of four experimental supplements containing linseed oil (LO), soybean oil (SO), palm oil (PO), or a control supplement without fatty acids (CO), for 15 days. Does were fitted with a controlled internal drug release (CIDR) device containing 0.3 g progesterone for 7 days. At 48 h before CIDR withdrawal, does were treated with 80 mg follicle-stimulating hormone (FSH) administered at 12 h intervals. Embryos were collected 7 days after the last natural mating. Estrous response and interval between CIDR withdrawals to estrous onset were similar between treatments (P > 0.05). Number of ovulations was similar for does in the different groups (10.0, 9.2, 7.0, and 7.0, in LO, SO, PO, and CO, respectively; P > 0.05). There was premature luteal regression in does of the SO, PO, and CO groups, except in LO group. The LO-treated does had a larger (P < 0.05) mean number of ova/embryos recovered than does of SO, PO, and CO groups (7.2, 2.0, 0.2, 0.2, respectively) and transferable embryos (5.1, 1.4, 0.2, 0.2, respectively). These results indicate that including LO in supplements may be a feasible strategy for preventing premature luteal regression and improving embryo quality in goats treated to induce follicular super-stimulation for induction of superovulation.

Follicle-stimulating hormone receptors expression in ovine corpora lutea during luteal phase: effect of nutritional plane and follicle-stimulating hormone treatment.

Corpus luteum (CL), a transient endocrine gland critical for reproductive cyclicity and pregnancy maintenance, is controlled by numerous regulatory factors. Although LH is widely recognized as the major regulator, other factors may also affect luteal functions. It has been demonstrated that FSH receptors (FSHR) are expressed not only in ovarian follicles but also in other tissues within the reproductive tract, including the CL. To evaluate FSHR expression in nontreated (nonsuperovulated; experiment 1) or FSH-treated (superovulated; experiment 2) sheep fed a control (C; maintenance), excess (O; 2 × C), or restricted (U; 0.6 × C) diet, CL were collected at the early, mid and/or late luteal phases (n = 5-7 per group). Protein and messenger RNA (mRNA) expression of FSHR were detected in the CL from all groups using immunohistochemistry followed by image analysis and quantitative RT-PCR, respectively. Follicle-stimulating hormone receptor was immunolocalized to steroidogenic small and large and nonsteroidogenic luteal cells. In both experiments, FSHR protein expression was not affected by stage of luteal development or diet. In experiment 1, expression of mRNA for all FSHR variants was greater (P <0.02 to 0.0003) at the late phase than mid or early luteal phase, and in experiment 2, it was greater (P < 0.001) at the mid than early luteal phase. Plane of nutrition did not affect FSHR mRNA expression. Comparison of FSH-treated with nontreated ewes demonstrated that FSH increased FSHR protein expression by 1.5- to 2-fold (P < 0.0001) in all groups, and mRNA expression by 7- to 30-fold (P < 0.001) for (1) FSHR-1 in all groups except U at the early luteal phase, (2) FSHR-2 in C, O, and U at the mid-phase, but not early luteal phase, and (3) FSHR-3 in U at the mid-luteal phase. Our data demonstrate that (1) FSHRs are expressed in ovine CL at several stages of luteal development, (2) FSHR protein expression does not change during the luteal phase and is not affected by diet, (3) FSHR mRNA expression not only depends on the stage of the estrous cycle but also not affected by diet in nonsuperovulated or superovulated ewes, and (4) in vivo FSH treatment enhanced FSHR protein and/or mRNA expression in the CL depending on diet and phase of the estrous cycle. Presence of FSHR in the CL indicates a regulatory role of FSH in luteal function in sheep. As very little is known about the possible role of FSH and FSHR in luteal functions, further studies should be undertaken to elucidate the endocrine, molecular, and cellular mechanisms of FSH effects on the CL.

Flaxseed improves embryo production in Boer goats.

Flaxseed is a source of polyunsaturated fatty acids and could be used as a dietary ingredient to enhance reproductive performance of ruminants. The objectives of this study were to determine the effect of feeding diets with different levels of flaxseed on the nutrient intake, and quantity and quality of embryos in Boer goats. A total of 24 multiparous Boer goats were fed with a diet containing either 0, 4, 8 or 12% of flaxseed (n = 6 per group) and subjected to superovulation to determine the quantity and quality of embryos collected on 7 d after natural service. The nutrient intake was linearly associated with levels of flaxseed in the diet and, whereas while the fat (measured as ether extract) intake was positively associated, the non-fiber carbohydrate intake had a negative association with increasing levels of flaxseed in the diet. The quantity, quality and stage of embryonic development on 7 d after natural service were significantly different between levels of flaxseed in the diet. The number of viable embryos was greater in goats fed with a diet containing 4, 8, and 12% flaxseed (94, 84, and 87%, respectively) than those fed with a diet containing 0% flaxseed (65%). On the other hand, the number of degenerated embryos was greater for goats fed with a diet containing 0% flaxseed (35%) than those fed with a diet containing 4, 8, and 12% flaxseed (6, 16, and 13%, respectively). The proportion of grade 1 embryo collected was greater for goats fed with a diet containing 4 and 8% flaxseed (74 and 83%, respectively) than those fed with a diet containing 0 and 12% flaxseed (40 and 46%, respectively). In summary, our study demonstrated that feeding a diet with moderate levels of flaxseed could produce a greater number of better-quality embryos in Boer goats.

Melatonin alleviates the deterioration of oocytes from mice subjected to repeated superovulation.

Induction of repeated superovulation with exogenous hormones is widely used in assisted reproductive technology (ART). Though it is generally safe, emerging evidence has indicated that repeated superovulation may compromise oocyte quality. However, few studies have explored how to ameliorate such impairment. Because melatonin has beneficial influences on oocytes in various detrimental environments, we aimed to explore whether melatonin could protect mouse oocytes after repeated superovulation. We found that repeated superovulation markedly reduced meiotic maturation and disrupted spindle organization and chromosome alignment. Furthermore, we observed reduced mitochondrial content and enhanced early apoptosis in oocytes from mice subjected to repeated superovulation. In addition, 5-methylcytosine (5mc) fluorescence intensity was lower in oocytes from experimental mice than in those from control mice, indicating that repeated superovulation disrupts genomic DNA methylation, and elevations in reactive oxygen species levels indicated that repeated superovulation also induces oxidative stress. Conversely, melatonin administration improved oocyte maturation and attenuated the observed defects. Interestingly, supplementation with melatonin during in vitro maturation had the same protective effects on oocytes as in vivo melatonin administration. In summary, our results show that melatonin can improve oocyte quality after repeated superovulation and thus provide a potential strategy to improve ART efficiency.

Effects of acupuncture on the levels of serum estradiol and pituitary estrogen receptor beta in a rat model of induced super ovulation.

AIMS: Acupuncture is frequently recommended as a complementary therapy for infertility. However, whether acupuncture can prevent early ovarian hyperstimulation syndrome has not been examined and its potential mechanisms are not well understood. MAIN METHODS: Forty rats were randomized into four groups: Control, Ovarian Stimulation Model, Acupuncture, and Human Chorionic Gonadotropin (HCG). Serum estradiol, progesterone, testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels were measured by enzyme-linked immunosorbent assay. Pituitary ER mRNA and ERß expression were detected by real-time PCR and western blotting respectively. The pathology of rat ovaries were observed by light microscopy. KEY FINDINGS: We observed significantly lower estradiol levels in the Acupuncture group than in the Model group and increased LH levels in the HCG group than in Model and Acupuncture groups. Testosterone and FSH levels were significantly lower in the Acupuncture group than in the HCG group. Western blotting showed significantly lower pituitary ERß expression in the Model group than in the Control group and higher expression in the Acupuncture group than in the Model group. Real-time PCR showed lower pituitary ER mRNA expression in the Acupuncture group than in the Model group. Hematoxylin and eosin staining showed a lower proportion of atretic follicles in Acupuncture and HCG groups than in Model and Control groups. Instead, Acupuncture and HCG groups showed growing and mature follicles. SIGNIFICANCE: Our results demonstrate a relationship between acupuncture and the hypothalamic-pituitary-gonadal axis, and the potential mechanism underlying the preventative effects of acupuncture on the incidence of early ovarian hyperstimulation syndrome.