Captive flatfishes, such as the Senegalese sole, typically produce very low volumes of sperm. This situation is particularly prevalent in the first generation (F1) of reared sole males, which limits the development of artificial fertilization methods and the implementation of selective breeding programs. In this study, we investigated whether combined treatments with homologous recombinant follicle-stimulating (rFsh) and luteinizing (rLh) hormones, produced in a mammalian host system, could stimulate spermatogenesis and enhance sperm production in Senegalese sole F1 males. In an initial autumn/winter experiment, weekly intramuscular injections with increasing doses of rFsh over 9 weeks resulted in the stimulation of gonad weight, androgen release, germ cell proliferation and entry into meiosis, and the expression of different spermatogenesis-related genes, whereas a subsequent single rLh injection potentiated spermatozoa differentiation. In a second late winter/spring trial corresponding to the sole’s natural prespawning and spawning periods, we tested the effect of repeated rLh injections on the amount and quality of sperm produced by males previously treated with rFsh for 4, 6, 8 or 10 weeks. These latter results showed that the combination of rFsh and rLh treatments could increase sperm production up to 7 times, and slightly improve the motility of the spermatozoa, although a high variability in the response was found. However, sustained administration of rFsh during spawning markedly diminished Leydig cell survival and the steroidogenic potential of the testis. These data suggest that in vivo application of rFsh and rLh is effective at stimulating spermatogenesis and sperm production in Senegalese sole F1 males, setting the basis for the future establishment of recombinant gonadotropin-based hormone therapies to ameliorate reproductive dysfunctions of this species.

The aquaculture of meagre (Argyrosomus regius) requires methods for the control of reproduction that enable the production of families from specific individuals for selective breeding programs. We experimentally determined the parameters required for an in vitro fertilisation protocol. A total of 14 females and 5 males (mean ± S.D. weights of 20.45 ± 6.22 and 15.94 ± 2.75 kg, respectively) were used. Selected females had vitellogenic oocytes >550 μm in diameter and males had fluid sperm upon application of abdominal pressure. Both sexes were treated with an injection of 15 μg kg−1 of gonadotropin-releasing hormone agonist (GnRHa) to induce oocyte maturation/ovulation and enhance sperm production. To determine the timing of ovulation and window of high egg viability, females were stripped serially every 2.5 h beginning 35 h after GnRHa treatment. Sperm was obtained 24 h after GnRHa treatment and was diluted 1/4 in modified Leibovitz for storage at 4 °C until use. Sperm quality parameters such as percentage initial spermatozoa motility, duration of motility, velocity and density were determined using computer assisted sperm analysis (CASA). In vitro inseminations were made in duplicate or triplicate batches of eggs from each spawn by mixing 0.5-1 mL of eggs, 20-40 μL diluted sperm (pooled from two males) and 100 mL of seawater. Fertilisation success was examined at spermatozoa (spz): egg ratios between ~2000 and 400,000 spz egg−1. The optimal time for stripping ovulated females was ≤3 h after ovulation, which was the window of optimal egg viability. Ovulation under the conditions of this study was close to 38 h after GnRHa treatment, with a range from 35 to 41 h. Beginning from 3 h after ovulation, egg viability declined probably due to overripening. Sperm diluted in Leibovitz maintained motility and velocity for as long as 7 h after collection. Spermatozoa motility (%) and average path velocity (VAP, μm/s) of sperm samples obtained from males before GnRHa injection declined rapidly after activation compared to the samples obtained 24 h post-injection, with significant decreases respectively after 75 and 45 s. A minimum ratio of 150,000 spermatozoa egg−1 was necessary to ensure high fertilisation success. The acquired knowledge of the present study will aid the aquaculture industry and future research on selective breeding programs for meagre. Highlights ► An in vitro fertilisation protocol has been developed for meagre (Argyrosomus regius). ► Ovulation took place close to 38 h and in the range of 35-41 h after GnRHa induction at 18 °C. ► Good quality eggs were collected within a three-hour window from ovulation. ► The spermatozoa: egg ratio for high fertilisation success was 150,000 spermatozoa egg −1 .

Consecutive treatments with recombinant follicle-stimulating and luteinizing hormones (rFsh and rLh, respectively) stimulate spermatogenesis and potentiate sperm production in pubescent specimens of the oligospermic Senegalese sole (Solea senegalensis). However, sperm production in response to the hormones is highly variable, and the steroidogenic potential of the testis may be diminished due to sustained hormone supply. Here, we compared the effectiveness of low (9 μg/kg) and high (18 μg/kg) doses of rFsh and rLh to improve sperm production in adult sole during late winter-early spring (onset of the natural spawning period), and in autumn under a controlled temperature of 12 °C (period of testicular recrudescence). Treatment with rFsh over six weeks during spring, followed by a single rLh injection, did not enhance sperm production, possibly because of an advanced stage of sexual maturation of the males, as reflected by high Lh plasma levels (~17 ng/ml) before rFsh treatment. In contrast, in autumn, when the Lh circulating levels were much lower (~3 ng/ml), the low doses of rFsh and rLh generated a four-times increase in sperm production, whereas the high doses of the hormones were ineffective. However, treatment with rLh, regardless of the effect of rFsh, improved the motility of spermatozoa during both spring and autumn. These data confirm that consecutive rFsh and rLh treatments increase sperm production and quality in adult sole males, although they seem to be highly sensitive to the rFsh dose. The efficiency of recombinant gonadotropins also appears to be season-dependent despite the asynchronous nature of the sole testis.

No abstract

Introduction Older adults are a highly vulnerable group in their general health condition, including oral health that can be influenced by different factors, among them, changes in oral tissues inherent to the physiological processes of aging and by systemic condition. In El Salvador, it is a group that has received little attention at the public health level. Objective To determine the profile of the oral health status and treatment needs of the elderly population in El Salvador. Materials and methods Secondary cross-sectional analysis of data from the last oral health survey in 471 Salvadorans aged 60 years and older. The variables under study were: sociodemographics, brushing frequency, oral hygiene according to simplified oral hygiene index (OHI-S), caries experience according to decayed, missing, and filled teeth index (DMFT) modified with international caries detection and assessment system (ICDAS) criteria, periodontal status through the community periodontal index of treatment needs (CPITN), edentulism and treatment needs. Statistical analysis was conducted using chi-square test, ANOVA, z-test and linear regression (p < 0.05). Results The older adults presented poor oral hygiene, low brushing frequency, high tooth loss with an average of 16 missing teeth while one third presented total edentulism. Most of the older adults were categorized as having "poor or very Poor" oral hygiene. Almost all respondents presented some degree of periodontal disease and required restorative intervention. Conclusion The oral health status of elderly Salvadoran is poor. Furthermore, the development of public policies and specific oral health strategies aimed at this population is urgent.