Inhibin: A Role for Fecundity Augmentation in Farm Animals

Expression of Hormones, Cytokines, and Antioxidants in Heat-Stressed Subfertile Female Dromedaries

Simple Summary

Heat stress imposes a high burden on domestic animals’ productive and reproductive performance. Due to the long hot summer, drought, and shortage of green fodders, camels raised in the desert suffer a lot of reproductive inefficiencies. This animal represents one of the main wealth sources for the desert inhabitants. Several fertility disorders have been discovered, leading to frequent breeding without pregnancy. This study aimed at exploring blood metabolites such as metabolic and reproductive hormones, cytokines, and antioxidants to be monitored as bio-indictors for subfertility in female camels. The results confirmed that none of the tested metabolic hormones and glucose revealed differences among fertile and subfertile females. However, FSH, inhibin, IL-ß, nitrous oxide, and glutathione revealed remarkable differences between fertile and subfertile females, which would be reliable tools to predict subfertility statuses in this animal. IL-ß revealed higher levels in the cases with genital inflammations. The normal profiles in control females revealed the highest FSH, and the lowest inhibin were vice versa in all subfertile females. Nonetheless, nitrous oxide and glutathione would also be reliable bio-indicators for judging the fertility status.

Abstract

The prevailing hot climate imposes heavy burdens on the productivity of the camel, goat, and sheep herds raised in the Gulf desert. Due to the lack of a reliable indicator for the various subfertility statuses in camel females, this study aimed to investigate the expression of inhibin, TGFά, ILß, FSH, sex and metabolic hormones, and antioxidants for the fertility status in camel females. Eighty-two subfertile and five fertile females were admitted to the university clinic with the complaint of repeat breeding with failed conception. The animal’s genital tracts were examined for reproductive soundness. Blood samples were withdrawn for hormonal, cytokines, and antioxidants determinations. Subfertile females were categorized into six groups; endometritis (EN, 28), inactive ovaries (IO, 20), ovarian hydrobursitis (BU, 19), vaginal adhesions (VA, 7), salpingitis (SA, 4), and cervicitis (CE, 4). Results revealed a significant increase in inhibin in all groups compared to control (68.2, 66.4, 61.8. 58.8, 58.3, 55.8, and 36 pg/mL, in CE, VA, IO, BU, EN, SA, and CON, respectively). TGFά, dehydroepiandrosterone (DHEA), and progesterone were not different among groups, whereas IL-ß differed among groups. FSH, estradiol, nitrous oxide, and glutathione were higher in CON compared with other groups. In conclusion, reproductive failures in camel females are reflected in the imbalances of endocrine, cytokines, and antioxidants bio-indicators.

Towards Improving the Outcomes of Multiple Ovulation and Embryo Transfer in Sheep, with Particular Focus on Donor Superovulation

Considerable improvements in sheep multiple ovulation and embryo transfer (MOET)protocols have been made; however, unlike for cattle, MOET is poorly developed in sheep, and thus has not been broadly applicable as a routine procedure. The tightly folded nature of the ewe cervix, the inconsistent ovarian response to various superovulatory treatments, and the requirement of labor to handle animals, particularly during large-scale production, has limited the implementation of successful MOET in sheep. Moreover, several extrinsic factors (e.g., sources, the purity of gonadotrophins and their administration) and intrinsic factors (e.g., breed, age, nutrition, reproductive status) severely limit the practicability of MOET in sheep and other domestic animals. In this review, we summarize the effects of different superovulatory protocols, and their respective ovarian responses, in terms of ovulation rate, and embryo recovery and transfer. Furthermore, various strategies, such as inhibin immunization, conventional superovulation protocols, and melatonin implants for improving the ovarian response, are discussed in detail. Other reproductive techniques and their relative advantages and disadvantages, such as artificial insemination (AI), and donor embryo recovery and transfer to the recipient through different procedures, which must be taken into consideration for achieving satisfactory results during any MOET program in sheep, are also summarized in this article.

Epitope-based in silico peptide design yields peptide-directed antibodies that recognize the buffalo luteinizing hormone

We present a novel peptide sequence identified through in silico epitope design and the later generation of peptide-directed antibodies recognizing the buffalo luteinizing hormone. Peptides and antibodies, specific to reproductive hormones, are valuable tools for developing point-of-care immunodiagnostic tools. The study predicted an epitope peptide in silico from buffalo luteinizing hormone and the generation of polyclonal antibodies against this peptide sequence. In this quest, we identified a novel epitope peptide sequence (luteinizing hormone peptide, LHP) through bioinformatics tools. The peptide was further synthesized and characterized. The polyclonal antibodies (anti-LHP) were raised against the peptide in the rabbit. Thereafter, we explored a strategy for detecting buffalo luteinizing hormone (LH) using the anti-peptide antibodies developed. The affinity of the peptide, bovine lutropin beta, and crude LH (prepared from buffalo pituitary) towards the raised antibodies was established by dot blot and ELISA. Specific recognition of the luteinizing hormone by the raised polyclonal antibodies highlights the ability of the identified peptide (LHP) and developed polyclonal antibodies (anti-LHP) as suitable diagnostic reagents for sensing the buffalo luteinizing hormone. Through this work, we analyzed and translated the "-omics" information in the LH gene sequence for the development of a novel peptide and antibodies as valuable immuno-reagents.

Reproductive immunology in viviparous mammals: evolutionary paradox of interactions among immune mechanisms and autologous or allogeneic gametes and semiallogeneic foetuses

Literally, reproductive immunology was born in bovine on-farm reproduction where seminal experiments intended for developing methods for embryo transfer in cattle were performed. Actually, these experiments led to two of major concepts and fundamental principles of reproductive immunology using the bovine species as a model for biomedical research, namely the concept of acquired immunological tolerance and the paradox of the semiallogeneic bovine foetus whereby such organism can develop within an immunologically competent host. Peter Medawar, a scientist who together with Frank Macfarlande Burnet shared the 1960 Nobel Prize in physiology or medicine for discovery of acquired immunological tolerance, while studying dizygotic cattle twins, thereby giving birth to reproductive immunology. Also, these findings significantly influenced development of organ transplants and showed that using farm animals as models for studying transplantation immunology had general relevance for mammalian biology and health including those of humans. However, the interest for further research of the fascinating maternal immune influences on pregnancy and perinatal outcomes and of the prevention and treatment of immunologically mediated reproductive disorders in viviparous mammals of veterinary relevance by veterinary immunologists and reproductive clinicians have been very scarce regarding the application of nonspecific immunomodulatory agents for prevention and treatment of subfertility and infertility in pigs and cattle, but still broadening knowledge in this area and hold great potential for improving such therapy in the future. The aim of the current overview is to provide up-to-date information and explaining/translating relevant immunology phenomena into veterinary practice for specialists and scientists/clinicians in reproduction of animals.

Immunohistochemical localization of inhibin/activin subunits in adult Asian elephant (Elephas maximus) testes

Immunolocalization of inhibin-α and inhibin/activin βA and βB subunits in the testes of Asian elephant was determined. Testicular sections were immunostained with polyclonal antisera against inhibin subunit-α and inhibin/activin βA and βB using the avidin-biotin-peroxidase complex method. Positive immunostaining against inhibin-α subunit was strongly present in Sertoli cells, and positive immunostaining for the inhibin/activin βA and βB subunits was observed in both Sertoli and Leydig cells. These results indicated that while Sertoli cells are the predominant source of inhibin and activin secretions in the testes of adult male Asian elephant, Leydig cells are a source of activin but not inhibin.

Trends in recombinant protein use in animal production

Recombinant technologies have made possible the production of a broad catalogue of proteins of interest, including those used for animal production. The most widely studied proteins for the animal sector are those with an important role in reproduction, feed efficiency, and health. Nowadays, mammalian cells and fungi are the preferred choice for recombinant production of hormones for reproductive purposes and fibrolytic enzymes to enhance animal performance, respectively. However, the development of low-cost products is a priority, particularly in livestock. The study of cell factories such as yeast and bacteria has notably increased in the last decades to make the new developed reproductive hormones and fibrolytic enzymes a real alternative to the marketed ones. Important efforts have also been invested to developing new recombinant strategies for prevention and therapy, including passive immunization and modulation of the immune system. This offers the possibility to reduce the use of antibiotics by controlling physiological processes and improve the efficacy of preventing infections. Thus, nowadays different recombinant fibrolytic enzymes, hormones, and therapeutic molecules with optimized properties have been successfully produced through cost-effective processes using microbial cell factories. However, despite the important achievements for reducing protein production expenses, alternative strategies to further reduce these costs are still required. In this context, it is necessary to make a giant leap towards the use of novel strategies, such as nanotechnology, that combined with recombinant technology would make recombinant molecules affordable for animal industry.

Correlation of inhibin and several antioxidants in children with acute lymphoblastic leukemia

BACKGROUND

Acute lymphoblastic leukemia (ALL) is most common in childhood. Inhibin (a non-steroidal glycoprotein hormone of gonadal origin) can be used as marker of fertility. The current study was conducted to evaluate inhibin levels in ALL patients and to estimate its correlation with some antioxidants in these in comparison with control subjects.

MATERIALS AND METHODS

This study was conducted on sixty patients with ALL and thirty children as controls. Fasting blood samples were taken from each subject and analyzed for haemoglobin, serum protein, vitamin E and C, in addition to glutathione and inhibin.

RESULTS

The results of the study showed highly significant decreases (p<0.001) in haemoglobin, glutathione and inhibin levels with significant decreases (p<0.05) in serum protein and vitamin E levels for patients group in comparison with controls while there was no significant differences in vitamin C. Moreover, there were significant correlations between inhibin levels and serum protein, glutathione and both vitamins (E and C) in the ALL patient group (r= 0.81, 0.80, 0.77 and 0.69, respectively).

CONCLUSIONS

The present results indicated infertility in patients with ALL demonstrated by low inhibin level as a consequence of abnormality in anti-oxidative metabolism due to the cancer process. So, it can be suggested the need for routine measurement of inhibin for leukemic patients to estimate the action of hormones of gonadal origin.

Subsequent influences of feeding intact green seaweed Ulva lactuca to growing lambs on the seminal and testicular characteristics in rams

The present experiment was designed to investigate the subsequent influences of supplementing different levels of intact green seaweed Ulva lactuca (0%, 3%, and 5% DM) to growing sexually immature lambs during the growth period (74 d) on the seminal and testicular characteristics of sexually mature rams. Ulva lactuca was manually collected, adequately prepared, and then incorporated into lambs' diets. Eighteen male 3-mo-old lambs of the Awassi breed with a mean BW of 22.57 kg (SD = 1.08) were randomly assigned into treatments. The obtained results indicate that offering Ulva lactuca at the level of 3% or 5% DM to lambs during the growth period had no subsequent impacts (P > 0.05) on liver and kidney functions as well as blood water balance in rams, thereby suggesting that Ulva lactuca can be safely supplemented to lambs during growing. However, our findings point out that feeding a lamb diet supplemented with intact Ulva lactuca failed to demonstrate any subsequent benefit (P > 0.05) on the growth performance, thermoregulatory responses, and plasma oxidative status in rams. Above all, it was clearly evident that supplementing intact Ulva lactuca to lambs had demonstrated subsequent negative influences (P < 0.05) on seminal and testicular characteristics of rams, more noticeably observed at the 5% DM inclusion rate than at 3%. These results were manifested by the inferior (P < 0.05) seminal quality, reduced (P < 0.05) testicular morphometry, changes (P < 0.05) in testicular histopathology, defective (P < 0.05) endocrine signaling, and increased (P < 0.05) seminal oxidative stress in rams fed diets supplemented with Ulva lactuca during the growth period compared to control rams. The deleterious impacts of feeding intact Ulva lactuca on spermatogenesis and germ cell loss were proven to be attributed to the dysfunction of Sertoli cells. Collectively, these results provide novel insights on the subsequent influences of dietary supplementation of intact Ulva lactuca to lambs. The consistent evidence of profound negative impacts on seminal and testicular characteristics as well as the resulting data of no improvement of subsequent growth, thermoregulation, and plasma oxidative status in rams prompts us to tentatively recommend the avoidance of feeding intact Ulva lactuca to lambs.