Background/Objectives: Research on cashmere goat coat color is crucial for optimizing cashmere goat breeds and increasing their economic value. To identify key genes associated with the formation of cashmere goat coat color and to provide molecular markers for breeding purposes, three healthy, 3-year-old does with similar weights and distinct coat colors—white, black, and light brown—were selected. Methods: Skin samples were collected for transcriptome sequencing, and bioinformatics methods were applied to screen for differentially expressed genes (DEGs) in the skin of cashmere goats with varying coat colors. Real-time fluorescence quantitative PCR (qRT-PCR) and immunofluorescence were subsequently conducted to examine the expression patterns of these DEGs. Results: The results showed that a total of 1153 DEGs were identified across the three groups of cashmere goats. According to GO and KEGG analyses, these DEGs were involved in key biological processes and structures, such as the melanin biosynthetic process (GO:0042438), melanosome membrane (GO:0033162), and melanin biosynthesis from tyrosine (GO:0006583). Employing Cytoscape, a gene interaction network was plotted, highlighting a compact network of DEGs associated with coat color formation. Critical genes identified included TYRP1, TYR, DCT, ASIP, PMEL, LOC102180584, MLANA, TSPAN10, TRPM1, CLDN16, AHCY, LOC106503350, and LOC102175263. qRT-PCR and fluorescence immunohistochemistry further determined that TYRP1, TYR, DCT, and PMEL expression levels were high in black goats (BGs), while ASIP and AHCY expression levels were high in white goats (WGs). The expression levels of these six genes in light brown goats (RGs) were intermediate between those in BGs and WGs. Conclusions: TYRP1, TYR, DCT, and PMEL were believed to play pivotal roles in the formation of black coat color, while ASIP and AHCY regulated the formation of white coat color in cashmere goats.

The aim of this experiment was to investigate the differences in metabolites in perirenal fat (PF) between Chinese Simmental cattle and Angus cattle. Six healthy 18-month-old male Angus cattle and Chinese Simmental cattle were selected, and the perirenal adipose tissue was collected after slaughtering. HE staining, a triglyceride assay kit, and liquid chromatography–tandem mass spectrometry (LC-MS/MS) technology were used to compare and analyze the differences in the cell morphology, lipid accumulation, and metabolites of the two types of PF. The results showed that the PF of Angus cattle had a larger cell area and stronger lipid deposition ability than that of Simmental cattle. A total of 567 metabolites were detected by LC-MS/MS technology, of which 119 were significantly upregulated in Angus cattle PF and 129 were significantly upregulated in Simmental cattle PF. Differential metabolites were enriched in pathways such as fatty acid biosynthesis, polyunsaturated fatty acid biosynthesis, regulation of adipocyte lipolysis, and oxidative phosphorylation. Finally, 12 metabolites that may cause phenotypic differences between the two types of perirenal adipose tissue were screened out from these pathways. This study has preliminarily screened out biomarkers that may affect lipid metabolism in PF, providing basic data for the further exploration of the metabolic characteristics of PF.

To assess the genetic diversity and matrilineal differentiation between the Betpak-Dala (BD) and Volga–Ural (VU) populations of Saiga tatarica in Kazakhstan, this study sequenced and comparatively analyzed the complete mitochondrial genomes of both populations. Phylogenetic analyses showed that Saiga tatarica clustered with the genera Gazella, Nanger, and Eudorcas, indicating a close evolutionary relationship. Genetic diversity analysis revealed that the BD population exhibited higher nucleotide diversity than the VU population. A total of 22 haplotypes were identified based on complete mitochondrial genome sequences, and no haplotypes were shared between the two populations, indicating pronounced matrilineal genetic differentiation. Synonymous mutations predominated among protein-coding genes, with the NADH dehydrogenase subunit 2 gene (nd2) and NADH dehydrogenase subunit 5 gene (nd5) genes exhibiting high levels of variation and serving as key regions for the accumulation of genetic diversity within the mitochondrial genome. These findings enhance the understanding of the genetic diversity and matrilineal genetic structure of Saiga tatarica populations in Kazakhstan and provide valuable information for their conservation and management.