Spermiogenesis, Stages of Seminiferous Epithelium and Variations in Seminiferous Tubules during Active States of Spermatogenesis in Yangzhou Goose Ganders

Protein profile analysis of Jilin white goose testicles at different stages of the laying cycle by DIA strategy

BACKGROUND

Jilin white goose is an excellent local breed in China, with a high annual egg production and laying eggs mainly from February to July each year. The testis, as the only organ that can produce sperm, can affect the sexual maturity and fecundity of male animals. Its growth and development are affected and regulated by a variety of factors. Proteomics is generally applied to identify and quantify proteins in cells and tissues in order to understand the physiological or pathological changes that occur in tissues or cells under specific conditions. Currently, the female poultry reproductive system has been extensively studied, while few related studies focusing on the regulatory mechanism of the reproductive system of male poultry have been conducted.

RESULTS

A total of 1753 differentially expressed proteins (DEPs) were generated in which there were 594, 391 and 768 different proteins showing differential expression in three stages, Initial of Laying Cycle (ILC), Peak of Laying Cycle (PLC) and End of Laying Cycle (ELC). Furthermore, bioinformatics was used to analyze the DEPs. Gene ontology (GO) enrichment, Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction (PPI) network analysis were adopted. All DEPs were found to be implicated in multiple biological processes and pathways associated with testicular development, such as renin secretion, Lysosomes, SNARE interactions in vesicle trafficking, the p53 signaling pathway and pathways related to metabolism. Additionally, the reliability of transcriptome results was verified by real-time quantitative PCR by selecting the transcript abundance of 6 selected DEPs at the three stages of the laying cycle.

CONCLUSIONS

The funding in this study will provide critical insight into the complex molecular mechanisms and breeding practices underlying the developmental characteristics of testicles in Jilin white goose.

Steps of spermiogenesis in the ostrich (Struthio camelus)

Few studies describe the sequence of morphological events that characterize spermiogenesis in birds. In this paper, the clearly observable steps of spermiogenesis are described and illustrated for the first time in a commercially important ratite, the ostrich, based on light microscopy of toluidine blue-stained plastic sections. Findings were supplemented and supported by ultrastructural observations, PNA labeling of acrosome development, and immunocytochemical labeling of isolated spermatogenic cells. Spermiogenesis in the ostrich followed the general pattern described in non-passerine birds. Eight steps were identified based on changes in nuclear shape and contents, positioning of the centriolar complex, and acrosome development. Only two steps could be recognized with certainty during development of the round spermatid which contributed to the fewer steps recorded for the ostrich compared to that described in some other bird species. The only lectin that displayed acrosome reactivity was PNA and only for the first three steps of spermiogenesis. This suggests that organizational and/or compositional changes may occur in the acrosome during development and merits further investigation. Immunological labeling provided additional evidence to support the finding of previous studies that the tip of the nucleus in the ostrich is shaped by the forming acrosome and not by the microtubular manchette. To our knowledge, this is the first complete description of spermiogenesis in ostrich and one of few in any avian species. In addition to comparative reproduction and animal science, this work has implications for evolutionary biology as the reported germ cell features provide a bridge between reptile and ratite-avian spermatogenesis.

Slaughter performance of the main goose breeds raised commercially in China and nutritional value of the meats of the goose breeds: a systematic review

A number of goose breeds are raised commercially in China. However, the data on the slaughter performance of the goose breeds and the nutritional value of their meats lack a thorough comparative analysis. In this systematic review, the slaughter performance of the goose breeds and nutritional value of their meats were comparatively analyzed to provide an overview of the characteristics of the goose breeds raised commercially in China. Fifteen goose breeds were selected from 27 research articles published up to January 2022 on the slaughter performance of the goose breeds raised commercially in China and their nutrient composition after literature searching, literature screening, variety selection, and data collation. The slaughter indexes of the goose breeds and the basic nutrient composition, amino acid composition, and fatty acid composition of the meats of the goose breeds were standardized using min-max normalization and compared. The results suggest that the slaughter indexes and nutritional indicators of the meats of Yangzhou white goose, Xupu goose, Landaise geese, and Sichuan white goose are more balanced than those of the meats of the other goose breeds. The results of this review can lay the foundation for optimizing the breeding methods of the commercially raised goose breeds and processing methods of the meats of the geese. © 2022 Society of Chemical Industry.

Role of sphingolipid metabolites in the homeostasis of steroid hormones and the maintenance of testicular functions

With the acceleration of life pace and the increase of work pressure, the problem of male infertility has become a social problem of general concern. Sphingolipids are important regulators of many cellular processes like cell differentiation and apoptosis, which are ubiquitously expressed in all mammalian cells. Various sphingolipid catabolic enzymes can generate multiple sphingolipids like sphingosine-1-phosphate and sphingomyelin. Present studies have already demonstrated the role of steroid hormones in the physiological processes of reproduction and development through hypothalamus-pituitary-gonad axis, while recent researches also found not only sphingolipids can modulate steroid hormone secretion, but also steroid hormones can control sphingolipid metabolites, indicating the role of sphingolipid metabolites in the homeostasis of steroid hormones. Furthermore, sphingolipid metabolites not only contribute to the regulation of gametogenesis, but also mediate damage-induced germ apoptosis, implying the role of sphingolipid metabolites in the maintenance of testicular functions. Together, sphingolipid metabolites are involved in impaired gonadal function and infertility in males, and further understanding of these bioactive sphingolipids will help us develop new therapeutics for male infertility in the future.

Ubiquitin C-terminal hydrolase L1 (UCHL1), a double-edged sword in mammalian oocyte maturation and spermatogenesis

BACKGROUND

Recent studies have shown that ubiquitin-mediated cell apoptosis can modulate protein interaction and involve in the progress of oocyte maturation and spermatogenesis. As one of the key regulators involved in ubiquitin signal, ubiquitin C-terminal hydrolase L1 (UCHL1) is considered a molecular marker associated with spermatogonia stem cells. However, the function of UCHL1 was wildly reported to regulate various bioecological processes, such as Parkinson's disease, lung cancer, breast cancer and colon cancer, how UCHL1 affects the mammalian reproductive system remains an open question.

METHODS

We identified papers through electronic searches of PubMed database from inception to July 2022.

RESULTS

Here, we summarize the important function of UCHL1 in controlling mammalian oocyte development, regulating spermatogenesis and inhibiting polyspermy, and we posit the balance of UCHL1 was essential to maintaining reproductive cellular and tissue homeostasis.

CONCLUSION

This study considers the 'double-edged sword' role of UCHL1 during gametogenesis and presents new insights into UCHL1 in germ cells.

Models and Molecular Markers of Spermatogonial Stem Cells in Vertebrates: To Find Models in Nonmammals

Spermatogonial stem cells (SSCs) are the germline stem cells that are essential for the maintenance of spermatogenesis in the testis. However, it has not been sufficiently understood in amphibians, reptiles, and fish because numerous studies have been focused mainly on mammals. The aim of this review is to discuss scientific ways to elucidate SSC models of nonmammals in the context of the evolution of testicular organization since rodent SSC models. To further understand the SSC models in nonmammals, we point out common markers of an SSC pool (undifferentiated spermatogonia) in various types of testes where the kinetics of the SSC pool appears. This review includes the knowledge of (1) common molecular markers of vertebrate type A spermatogonia including putative SSC markers, (2) localization of the markers on the spermatogonia that have been reported in previous studies, (3) highlighting the most common markers in vertebrates, and (4) suggesting ways of finding SSC models in nonmammals.

Improving Gander Reproductive Efficacy in the Context of Globally Sustainable Goose Production

The goose is a popular poultry species, and in the past two decades the goose industry has become highly profitable across the globe. Ganders low reproductive performance remains a barrier to achieving high fertility and hatchability in subsequent flocks. To address the global demand for cheaper animal protein, various methodologies for improving avian (re)production should be explored. A large amount of literature is available on reproduction traits and techniques for commercial chicken breeder flocks, while research on improved reproduction in ganders has been carried out to a lesser extent. The present review aims to provide a comprehensive literature overview focusing on recent advancements/techniques used in improving gander reproductive efficacy in the context of ensuring a globally sustainable goose industry.

The Effect of Inhibin Immunization in Seminiferous Epithelium of Yangzhou Goose Ganders: A Histological Study

The current study investigated the effect of inhibin immunization on germ cell numbers (spermatogonia, spermatocytes, round, and elongated spermatids), seminiferous tubules (ST) diameter, Johnsen's score, epithelial height (μm), luminal tubular diameter (μm), and number of ST per field (ST/field) of Yangzhou goose ganders. Histological evaluation showed apoptosis and regression of testes after inhibin (INH) immunization, with a concomitantly marked reduction in the round and elongated spermatids in the experiment (INH) group compared to the control group. The diameter of seminiferous tubules (ST) and epithelial height (EH) were positively correlated at 181, 200, and 227 days of age. In comparison, luminal tubular diameter (LD) was negatively correlated on day 227 to ST diameter and epithelial height. On day 227, many seminiferous tubules per field (ST/field) were negatively correlated to ST diameter, EH, and LD. INH immunization elevated ST diameter, EH, and LD, while Johnsen's score and number of ST/field had reciprocal expression. In conclusion, the concomitant effect of INH immunization and seasonality in breeding regressed germ cells and damaged spermatogenesis in seminiferous epithelium Yangzhou ganders.