Animal Reproduction最新文献

Deslorelin is a GnRH agonist used in veterinary medicine to temporarily inhibit reproduction in domestic animals and is sometimes tested in captive species in zoo to control population or tame aggressive behaviours in males. However, some studies have revealed the inefficacy of deslorelin specifically in males, contrary to females that follow a classic long-term inhibition of the reproductive hypothalamic-pituitary axis through sexual steroid negative feedback. We implanted 5 males and 6 females grey mouse lemurs (Microcebus murinus), long-day breeders that display a complete inhibition of the reproductive system during winter, at the end of the short-day period, a few weeks before the breeding season. Contrary to females, which exhibited a classic inhibitory response to deslorelin, males' testosterone levels increased as well as their testis size, which suggests a sex-specific sensitivity to the negative feedback of sexual steroids before the mating period. We propose that this sex-imbalance is related to the different life-history of males as opposed to females concerning reproductive tasks and behaviour.

The cooling of Litopenaeus vannamei shrimp spermatophores for assisted insemination can enable the transfer of gametes between reproduction laboratories. This study aimed to assess three extenders for cooling L. vannamei spermatophores for assisted insemination. Spermatophores were chilled at 15 °C for 24 or 48 hours using powdered coconut water ACP® (PCW), mineral oil (MO), and sterilized seawater (SSW) as extenders. All treatments demonstrated consistent responses over time. Apparent viability and morphological integrity percentages remained above 60% and 70%, respectively, across treatments and storage durations. Focusing on diluents, normal cell percentages for MO, SSW, and PCW treatments were 74.9±9.20%, 77.3±9.40%, and 78.1±6.35%, respectively, irrespective of storage time. The highest hatching rate was observed in the SSW treatment (80.67±12.01%), which was significantly superior to the PCW treatment (50.15±20.75%). The hatching rates observed in the MO treatment (71.47±18.83%) did not statistically differ from either PCW or SSW treatments. The cooling protocol successfully preserved the spermatophores' ability to maintain favorable levels of apparent viability, normal morphology, and hatching rates after 48 hours of storage at 15 °C using mineral oil, seawater, or ACP® as extenders. Sterilized seawater emerged as the most efficient diluent, delivering superior hatching rates following artificial insemination.

Anticancer therapy often leads to premature ovarian insufficiency (POI) and infertility due to the extreme sensitivity of the ovarian follicle reserve to the effects of chemotherapy. Withanolides are known for their cytotoxic effect on cancer cells and low cytotoxicity on non-malignant or healthy cells. Therefore, this study aimed to investigate the in vivo effects of three withanolides derivatives: 27-dehydroxy-24,25-epoxywithaferin A (WT1), 27-dehydroxywithaferin A (WT2), and withaferin A (WTA) on fertility, and the ovarian preantral follicles of young female mice. To achieve this, mice received 7 intraperitoneal doses of WT1, WT2, or WTA at a concentration of 2 mg/kg (Experiment I) and 5 or 10 mg/kg (Experiment II) over 15 alternate days. In experiment I, two days after administration of the last dose, half of the mice were mated to evaluate the effects of withanolides on fertility. The other half of the mice, as well as all mice from experiment II, were sacrificed for histological, inflammation, senescence, and immunohistochemical analyses of the follicles present in the ovary. Regardless of the administered withanolide, the concentration of 2 mg/kg did not show toxicity on the follicular morphology, ovarian function, or fertility of the mice. However, at concentrations of 5 and 10 mg/kg, the three derivatives (WT1, WT2, and WTA) increased follicular activation, cell proliferation, and ovarian senescence without affecting inflammatory cells. Furthermore, at a concentration of 10 mg/kg, the three withanolides showed intensified toxic effects, leading to DNA damage as evidenced by the labeling of γH2AX, activated Caspase 3, and TUNEL. We conclude that the cytotoxic effect of the tested withanolide derivatives (WT1, WT2, and WTA) in the concentration of 2 mg/kg did not show toxicity on the ovary. However, in higher concentrations, such as 10 mg/kg, toxic effects are potentiated, causing DNA damage.

Oviduct fluid extracellular vesicles (oEV) are essential for periconceptional events. The presence of EV has already been identified in the oviduct fluid (OF) from mammalian species, except in caprine. Therefore, this study aimed to isolate and characterize the caprine oEV (coEV). Initially, in Experiment 1, coEV were isolated from the OF of either each animal individually or from a pool of three animals. In experiment 2, coEV were isolated during the follicular or luteal phases of the estrous cycle. The coEV were characterized by size distribution, polydispersity index (PDI), and zeta potential using dynamic light scattering (DLS) analysis, as well as, by transmission electron microscopy (TEM) and dot blotting (DB). Our results indicated that the physicochemical characteristics of the coEV were similar (P > 0.05), regardless of the isolation method (individual or pool). However, coEV collected during the luteal phase were larger (P < 0.05) than those during the follicular phase. The TEM showed spherical and cup-shaped particles, characteristic of exosomes. The DB revealed the presence of exosomal proteins involved in the biogenesis of coEV. In conclusion, it is possible to isolate and characterize coEV from a single caprine female and the estrous cycle phase influences the vesicles average size and PDI.

The study aimed to evaluate the effectiveness of combining two injectable progesterone (iP4) formulas for estrous synchronization in ewes and to compare it with traditional intravaginal progesterone devices. Additionally, the study assessed whether the inclusion of GnRH enhances the reproductive outcomes of the iP4 treatment. Two experiments were conducted. In the first experiment, 20 Santa Inês ewes were divided into two groups: one group received intravaginal progesterone devices, and the other received combined long-acting and short-acting iP4. In the second experiment, 30 Corriedale ewes were divided into two groups: one received the combined iP4 with GnRH, and the other without GnRH. Estrous, ovulation, follicular populations, and progesterone concentrations were monitored. The combined iP4 treatment induced an artificial luteal phase and produced reproductive responses similar to those obtained with intravaginal devices. In the first experiment, the iP4 treatment tended to result in more synchronized ovulation compared to the control (P=0.095). In the second experiment, adding GnRH enhanced the quality of the corpus luteum, as indicated by increased diameter and vascularization on Day 23 (P=0.047 and P=0.02, respectively). The combined administration of long-acting and short-acting iP4 effectively synchronized estrous in ewes and showed similar efficacy to traditional intravaginal devices. The inclusion of GnRH improved luteal quality, suggesting potential benefits for reproductive management in ewes. Further studies are needed to evaluate the fertility outcomes of these protocols under field conditions.

Due to high annual culling rates, pig farms require a constant income of replacement gilts. Gilts typically reach puberty at nearly six months of age. Puberty may be induced through early boar exposure, therapy with steroid hormones and chorionic gonadotropins, and optimized by identifying biological predictors and risk factors. Old age at the time of the first mating is associated with an increased risk of premature culling, often attributed to reproductive failures and locomotor problems. While female prolifacy has increased substantially during the last few decades, selecting for litter size to optimize lifetime productivity would be more efficient after two parities. Additionally, uterine capacity and the number of functional teats should be considered in selecting future dams. For each female, the cost-effective number of parities at removal is determined by the cumulative number of pigs born and weaned during the total herd days.

The current investigation aimed to explore the effects of Myrciaria dubia liquid extract (MDLE) as the primary component of an extender for breeder rooster semen over different periods at room temperature. Fifteen breeder roosters (40 weeks of age, average body weight of 2.05±0.12) with confirmed fertility were used. Employing a factorial design (3x4), the treatments consisted of semen in natura and two semen extenders (an experimental based on MDLE and a commercial) subjected to four periods at room temperature post-collection (5, 10, 15 and 20 minutes) with four replicates (tubes) each. All variables evaluated in this study yielding significant results (p<0.05). Analyzed individually, the experimental extender based on MDLE exhibited a linear reduction (p<0.05) in motility and vigor results, while it caused an increase in pH values and percentages of sperm defects evaluated. When compared with semen in natura and commercial extender, the efficiency of MDLE as a semen extender was inferior to that observed with the commercial extender and similar to the results observed with semen in natura. Nonetheless, the experimental extender based on MDLE yielded satisfactory results for up to 15 minutes of storage time. In conclusion, MDLE can be considered as an alternative for composing a roosters' semen extender, maintaining sperm characteristics within acceptable limits for up to 15 minutes at room temperature. However, this experimental extender demonstrated lower efficiency than the commercial extender in maintaining the sperm quality at room temperature across all periods tested.

PICK1 plays a crucial role in mammalian spermatogenesis. Here, we integrated single-molecule long-read and short-read sequencing to comprehensively examine PICK1 expression patterns in adult Baoshan pig (BS) testes. We identified the most important transcript ENSSSCT00000000120 of PICK1, obtaining its full-length coding sequence (CDS) spanning 1254 bp. Gene structure analysis located PICK1 on pig chromosome 5 with 14 exons. Protein structure analysis reflected that PICK1 consisted of 417 amino acids containing two conserved domains, PDZ and BAR_PICK1. Phylogenetic analysis underscored the evolutionary conservation and homology of PICK1 across different mammalian species. Evaluation of protein interaction network, KEGG, and GO pathways implied that interacted with 50 proteins, predominantly involved in glutamatergic synapses, amphetamine addiction, neuroactive ligand-receptor interactions, dopaminergic synapses, and synaptic vesicle recycling, and PICK1 exhibited significant correlation with DLG4 and TBC1D20. Functional annotation identified that PICK1 was involved in 9 GOs, including seven cellular components and two molecular functions. ceRNA network analysis suggested BS PICK1 was regulated by seven miRNA targets. Moreover, qPCR expression analysis across 15 tissues highlighted that PICK1 was highly expressed in the bulbourethral gland and testis. Subcellular localization analysis in ST (Swine Tesits) cells demonstrated that PICK1 significantly localized within the cytoplasm. Overall, our findings shed new light on PICK1's role in BS reproduction, providing a foundation for further functional studies of PICK1.

The objective of the present study was to evaluate the effects of a novel Inhibin (INH) DNA vaccine (C500/pVAX-asd-IS) on the immune response, reproductive hormone levels, and spermatogenesis of rats. Forty healthy male rats were divided into four groups, and respectively immunized (thrice, 14 d apart) with 1×10⁸, 1×10⁹, and 1×10¹⁰ CFU of the recombinant inhibin vaccine (group C500/pVAX-asd-IS-L, C500/pVAX-asd-IS-M, and C500/pVAX-asd-IS-H) or 1×10¹⁰ CFU C500. P/N values increased after vaccination and differed (p <0.05) at 7 d, and sharply increased at 14 d following the booster vaccination (p <0.01); The weight and volume of testes in C500/pVAX-asd-IS groups were increased (p < 0.05) at decapitation, respectively; Histological evaluation showed that the number of spermatogenic cells in the lumen was increased, and the cytoplasmic remnants of sperms were allergy increased significantly compared with the control group. Oral vaccination with INH DNA reduced (P < 0.05) serum concentrations of INH B, enhanced serum concentrations of testosterone (T) and FSH. Furthermore, mRNA expressions of VIM and SMAD4 in the testes were increased in C500/pVAX-asd-IS-M and C500/pVAX-asd-IS-H groups (p < 0.05 or p < 0.01). The mRNA amount of INHβ-B in C500/pVAX-asd-IS-M group was greater than control group (p < 0.05).These results suggested that neutralization of endogenous INH through oral vaccination with INH DNA delivered by C500 strain successfully elicited a humoral immune response. INH gene immunization may have a positive effect on spermatogenesis and reproductive efficiency in male rats.

This brief review delves into the topic of in vitro follicle culture for in vitro embryo production, with a particular emphasis on goat models. Specifically, we examine the main findings from LAMOFOPA-Brazil over the last 20 years, highlighting the challenges posed by oxidative stress and epigenetic changes. Our focus is on strategies to improve follicular development and oocyte maturation. Furthermore, we underscore the valuable role of the antioxidant anethole in optimizing the efficacy of in vitro follicle culture and improving outcomes in in vitro embryo production.