Genome-Wide Association Study of Body Weight Traits in Inner Mongolia Cashmere Goats

Objective: Body weight is an important economic trait for a goat, which greatly affects animal growth and survival. The purpose of this study was to identify genes associated with birth weight (BW), weaning weight (WW), and yearling weight (YW).Materials and Methods: In this study, a genome-wide association study (GWAS) of BW, WW, and YW was determined using the GGP_Goat_70K single-nucleotide polymorphism (SNP) chip in 1,920 Inner Mongolia cashmere goats.Results: We discovered that 21 SNPs were significantly associated with BW on the genome-wide levels. These SNPs were located in 10 genes, e.g., Mitogen-Activated Protein Kinase 3 (MAPK3), LIM domain binding 2 (LDB2), and low-density lipoprotein receptor-related protein 1B (LRP1B), which may be related to muscle growth and development in Inner Mongolia Cashmere goats. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that these genes were significantly enriched in the regulation of actin cytoskeleton and phospholipase D signaling pathway etc.Conclusion: In summary, this study will improve the marker-assisted breeding of Inner Mongolia cashmere goats and the molecular mechanisms of important economic traits.

Single-Cell Sequencing Reveals Differential Cell Types in Skin Tissues of Liaoning Cashmere Goats and Key Genes Related Potentially to the Fineness of Cashmere Fiber

Cashmere fineness is one of the important factors determining cashmere quality; however, our understanding of the regulation of cashmere fineness at the cellular level is limited. Here, we used single-cell RNA sequencing and computational models to identify 13 skin cell types in Liaoning cashmere goats. We also analyzed the molecular changes in the development process by cell trajectory analysis and revealed the maturation process in the gene expression profile in Liaoning cashmere goats. Weighted gene co-expression network analysis explored hub genes in cell clusters related to cashmere formation. Secondary hair follicle dermal papilla cells (SDPCs) play an important role in the growth and density of cashmere. ACTA2, a marker gene of SDPCs, was selected for immunofluorescence (IF) and Western blot (WB) verification. Our results indicate that ACTA2 is mainly expressed in SDPCs, and WB results show different expression levels. COL1A1 is a highly expressed gene in SDPCs, which was verified by IF and WB. We then selected CXCL8 of SDPCs to verify and prove the differential expression in the coarse and fine types of Liaoning cashmere goats. Therefore, the CXCL8 gene may regulate cashmere fineness. These genes may be involved in regulating the fineness of cashmere in goat SDPCs; our research provides new insights into the mechanism of cashmere growth and fineness regulation by cells.

Screening of cashmere fineness-related genes and their ceRNA network construction in cashmere goats

Competitive endogenous RNA (ceRNA) is a transcript that can be mutually regulated at the post-transcriptional level by competing shared miRNAs. The ceRNA network connects the function of protein-encoded mRNA with the function of non-coding RNA, such as microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). However, compared with the ceRNA, the identification and combined analysis of lncRNAs, mRNAs, miRNAs, and circRNAs in the cashmere fineness have not been completed. Using RNA-seq technology, we first identified the miRNAs presented in Liaoning Cashmere Goat (LCG) skin, and then analyzed the mRNAs, lncRNAs, circRNAs expressed in LCG and Inner Mongolia cashmere goat (MCG) skin. As a result, 464 known and 45 new miRNAs were identified in LCG skin. In LCG and MCG skin, 1222 differentially expressed mRNAs were identified, 170 differentially expressed lncRNAs and 32 differentially expressed circRNAs were obtained. Then, qRT-PCR was used to confirm further the representative lncRNAs, mRNAs, circRNAs and miRNAs. In addition, miRanda predicted the relationships of ceRNA regulatory network among lncRNAs, circRNAs, miRNAs and mRNAs, the potential regulatory effects were investigated by Go and KEGG analysis. Through the screening and analysis of the results, the ceRNA network regulating cashmere fineness was constructed. LncRNA MSTRG14109.1 and circRNA452 were competed with miRNA-2330 to regulated the expression of TCHH, KRT35 and JUNB, which may provide a potential basis for further research on the process of regulating the cashmere fineness.

Altered Hypoxia-Induced and Heat Shock Protein Immunostaining in Secondary Hair Follicles Associated with Changes in Altitude and Temperature in Tibetan Cashmere Goats

This experiment compared secondary hair follicles (SFs) in Tibetan cashmere goats from two different steppes that were at different altitudes and had different temperatures. Twenty-four 2-year-old goats were studied. Twelve goats were from Rikaze in Tibet which is at an altitude of above 5000 m with an average temperature of 0 °C. The other 12 studied goats were from Huan County of Gansu Province which is around 2000 m above sea level with an average temperature of 9.2 °C. The structural features of SFs were assessed using light microscopy and transmission electron microscopy. The presence of HIF-1a, HIF-2a, HIF-3a, HSP27, and HOXC13 proteins was studied using immunohistochemistry and immunofluorescence. Light and electron microscopy revealed that the SFs of the Tibetan cashmere goats that lived in the Rikaze Steppe were in the proanagen stage in May. However, the SFs of the goats from the lower warmer Huan County were in the anagen stage at the same time. Immunohistochemistry revealed intense immunostaining for HIF-1a protein in the inner root sheath (IRS) and hair shaft (HS); immunostaining against HIF-2a in the outer root sheath (ORS) and IRS; HIF-3a protein immunostaining in the ORS; HSP27 immunostaining in the ORS, IRS, and HS; and HOXC13 immunostaining in the ORS and HS. HIF-1a protein expression in the IRS and HS was higher than the expression in the ORS (p < 0.05) while the expression of HIF-2a protein was higher in the ORS and IRS than the HS (p < 0.05). The expression of HIF-3a protein was higher in the ORS than in the IRS (p < 0.05). Expression of HOXC13 protein was higher in the ORS than in the IRS and HS (p < 0.05). Immunostaining of HIF-1a, HIF-2a, and HSP27 protein was significantly higher in SFs from cashmere goats from Rikaze than in goats from Huan (p < 0.05). In contrast, HOX13 protein immunostaining was significantly higher in cashmere goats from Huan than from Rikaze (p < 0.05). Significant differences were observed in the SFs of cashmere goats from two locations that differ in altitude and temperature. This suggests the differences in the secondary hair follicles could be due to the hypoxia and lower temperatures experienced by the goats in Rikaze. These results are useful in understanding how altitude and temperature influence SF development. Hair produced by the SFs are used for down fiber. Therefore, understanding of the factors that influence SF development will allow the production and harvest of these valuable fibers to be maximized.

Proteomic analysis of coarse and fine skin tissues of Liaoning cashmere goat

Proteomics is the study of all proteins expressed by a cell or even an organism. However, knowledge of proteins that regulate the fineness of cashmere is limited. Liaoning Cashmere goat (LCG) is a valuable genetic resource of China. The skin samples of Liaoning cashmere goats during the growing period were collected performed Tandem Mass Tag (TMT) method and identified 117 differentially expressed proteins in CT_LCG (course type) and FT_LCG (fine type). To verify protein genes differentially expressed in LCG, we performed PRM validation on three candidate proteins (ALB, SDC1 and ITGB4) in CT-LCG and FT-LCG. Furthermore, primary metabolic process and lysosome are most enriched in the GO and KEGG pathways, respectively. In addition, we also derived a protein-protein interaction (PPI) regulatory network from the perspective of bioinformatics. This study sought to elucidate the molecular mechanism of differential proteins regulating cashmere fineness of Liaoning cashmere goats by using TMT quantitative proteomics analysis. Differentially expressed proteins ALB and SDC1 may regulate cashmere fineness, ITGB4 can be further studied as a promising protein. Theycan be used as key genes to lay a foundation for the study of cashmere fineness of Liaoning cashmere goats.

Associative effects in diets composed of alfalfa and corn soybean concentrate fed to growing cashmere goats

The associative effects resulting from the proportions of neutral detergent fibre (NDF) and non fibre carbohydrate (NFC) were explored and assessed by in vitro gas production . Total mixed rations (TMR) composed primarily of alf a lfa and corn soybean concentrate were fed to growing cashmere goats. Treatments were defined by three proportions of NFC and NDF namely 2.00 ( TMR1), 2.35 ( TMR2), and 3.00 ( that were used to grow cashmere goats , and these TRMs were incubated for 48 h ours to evaluate their influence on associative effects. The results indicated that the associative influences of these treatments on gas production occurred within the cultures predominantly at 2 8 hours, and disappeared gradually as culture time was ex tended . TMR 2 and TMR3 incubation increased gas production compared with that observed in the other groups at all incubation times P > 0.05), and these groups exhibited positive associative effects, particularly during the early hours of incubation P <0.05 )). TMR 3 displayed the best associative effect.

Phenotypic characterization of Cashmere goats in Western Mongolia

This study was conducted as a preliminary study to design the breeding activity of Mongolian cashmere goats. To characterize the phenotypic traits of goats in Western Mongolia, the linear body measurements and cashmere yield and its the quality were measured. In this study, 608 cashmere goats were selected from the areas where it highly affected to overgrazing and overstocked in this area. The study used a random sampling method from the populations. The normality of the data was checked using the Shapiro-Wilk normality test and analyzed using the linear model procedure in R software. All male (buck) and female goats had straight head profiles (100%). Black coat color was predominant in Erdeneburen, Bayan-Uul soums and all of the goats in Ulgii soum were red. The goats in Ulgii soum were the biggest in body size compared to Erdeneburen and Bayan-Uul in Ulgii soums. The goats had back horn orientation (100%). Significant effects (p <0.001) of sex, age, locations, and sex*age classes were observed on live body weight, cashmere quantitative and qualitative characteristics, and linear body measurements.