Comparative transcriptomics analysis identifies crucial genes and pathways during goose spleen development.

As the largest peripheral lymphoid organ in poultry, the spleen plays an essential role in regulating the body's immune capacity. However, compared with chickens and ducks, information about the age- and breed-related changes in the goose spleen remains scarce. In this study, we systematically analyzed and compared the age-dependent changes in the morphological, histological, and transcriptomic characteristics between Landes goose (LG; Anser anser) and Sichuan White goose (SWG; Anser cygnoides). The results showed a gradual increase in the splenic weights for both LG and SWG until week 10, while their splenic organ indexes reached the peak at week 6. Meanwhile, the splenic histological indexes of both goose breeds continuously increased with age, reaching the highest levels at week 30. The red pulp (RP) area was significantly higher in SWG than in LG at week 0, while the splenic corpuscle (AL) diameter was significantly larger in LG than in SWG at week 30. At the transcriptomic level, a total of 1710 and 1266 differentially expressed genes (DEGs) between week 0 and week 30 were identified in spleens of LG and SWG, respectively. Meanwhile, a total of 911 and 808 DEGs in spleens between LG and SWG were identified at weeks 0 and 30, respectively. Both GO and KEGG enrichment analysis showed that the age-related DEGs of LG or SWG were dominantly enriched in the Cell cycle, TGF-beta signaling, and Wnt signaling pathways, while most of the breed-related DEGs were enriched in the Neuroactive ligand-receptor interaction, Cytokine-cytokine receptor interaction, ECM-receptor interaction, and metabolic pathways. Furthermore, through construction of protein-protein interaction networks using significant DEGs, it was inferred that three hub genes including BUB1, BUB1B, and TTK could play crucial roles in regulating age-dependent goose spleen development while GRIA2, GRIA4, and RYR2 could be crucial for the breed-specific goose spleen development. These data provide novel insights into the splenic developmental differences between Chinese and European domestic geese, and the identified crucial pathways and genes are helpful for a better understanding of the mechanisms regulating goose immune functions.

Developmental variations of the reproductive organs of ganders from different goose breeds and the underlying mechanisms.

A deep understanding of the dynamics and mechanisms of male reproductive tract development is necessary for adoption of either genetic techniques or environmental management practices for improving fertility and hatchability in poultry. However, compared with other poultry such as chickens and ducks, less is known about the age- and breed-related changes in the reproductive tract development of domestic goose ganders exhibiting relatively poor reproductive performance as well as the regulatory mechanisms. In the present study, by taking 2 Chinese domestic goose breeds (Sichuan White goose, SW and Gang goose, GE; Anser cygnoides) and one European goose breed (Landes goose, LD; Anser anser) as the experimental objects, we comprehensive analyzed the morphological, histological, and genome-wide transcriptomic variations in their testicular and external genital development during the period from hatching to sexual maturity. Results from histomorphological analysis demonstrated that the reproductive tract of all goose breeds developed in both age- and breed-dependent manners, and the left and right testis developed asymmetrically throughout posthatch development. The tenth week posthatch was a critical developmental stage for all goose ganders, because both the testicular and external genital histomorphological parameters significantly changed before and after this period. During the first 10 wk posthatch, the weight, organ index, or size of male reproductive organs developed more rapidly in SW than in LD, and so were the testicular parenchymal-to-interstitial ratio and the external genital lymphatic lumen diameter. However, the testicular seminiferous epithelium thickness, seminiferous tubule diameter, and Leydig cell number, as well as the external genital keratinized epithelium thickness were significantly higher in LD than in SW at 10 wk of age. Through comparative transcriptomics analysis and RT-qPCR validation, several pathways related to germ and somatic cell function, organ remodeling, and energy metabolism were thought to be responsible for the developmental variations in the early testicular development between Chinese and European domestic ganders, where 10 hub genes involved in the cell cycle, RNA polymerase II-dependent transcription, and mitotic cell division pathways might play essential roles. These data shed new light on the interbreed differences in the male goose reproductive tract development and the molecular mechanisms regulating male goose testicular functions and fertility.

Investigation on the Electrochemical Deposition of Nanocrystalline Zinc with Cationic Polyacrylamide (CPAM)-ZnSO4 Electrolyte.

The electrochemical deposition of nanocrystalline zinc has high potential to deposit zinc coatings, which have improved wear and corrosion properties compared to conventional coating methods. Conventionally, two or more additives are used in the electrolyte for the formation nanocrystalline zinc; these electrolyte components are complex, and their maintenance is inconvenient, making it unstable and not suitable for industrial scale production. This paper proposes an electrochemical deposition technique for nanocrystalline zinc using a ZnSO4 solution with cationic polyacrylamide (CPAM) as the unique additive. The results reveal that the cationic degree of CPAM has a significant influence on the deposition process and that the cationic degree of 20% enhances the electrolyte conductivity and improves the density of the deposited coating. The concentration of CPAM affects the electrolyte viscosity and conductivity. CPAM with a concentration of 20 g/L could simultaneously improve the electrolyte conductivity and maintain the viscosity at a low value, which promotes the formation of a bright deposited coating with a grain size of 87 nm. Additionally, the current density affects the grain structure of the deposited coating. With a current density of 0.5 A/dm2, a dense coating with lamellar grains and a grain size of 54.5 nm was obtained, which has, and the surface roughness was reduced to 0.162 µm. Moreover, the corrosion resistant property of the deposited coating was also improved.