Identification of genomic characteristics and selective signals in Guizhou black goat.

BACKGROUND: Guizhou black goat is one of the indigenous black goat breeds in the southwest region of Guizhou, China, which is an ordinary goat for mutton production. They are characterized by moderate body size, black coat, favorite meat quality with tender meat and lower odor, and tolerance for cold and crude feed. However, little is known about the genetic characteristics or variations underlying their important economic traits. RESULTS: Here, we resequenced the whole genome of Guizhou black goat from 30 unrelated individuals breeding in the five core farms. A total of 9,835,610 SNPs were detected, and 2,178,818 SNPs were identified specifically in this breed. The population structure analysis revealed that Guizhou black goat shared a common ancestry with Shaanbei white cashmere goat (0.146), Yunshang black goat (0.103), Iran indigenous goat (0.054), and Moroccan goat (0.002). However, Guizhou black goat showed relatively higher genetic diversity and a lower level of linkage disequilibrium than the other seven goat breeds by the analysis of the nucleotide diversity, linkage disequilibrium decay, and runs of homozygosity. Based on FST and θπ values, we identified 645, 813, and 804 selected regions between Guizhou black goat and Yunshang black goat, Iran indigenous goat, and cashmere goats. Combined with the results of XP-EHH, there were 286, 322, and 359 candidate genes, respectively. Functional annotation analysis revealed that these genes are potentially responsible for the immune response (e.g., CD28, CD274, IL1A, TLR2, and SLC25A31), humility-cold resistance (e.g., HBEGF, SOSTDC1, ARNT, COL4A1/2, and EP300), meat quality traits (e.g., CHUK, GAB2, PLAAT3, and EP300), growth (e.g., GAB2, DPYD, and CSF1), fertility (e.g., METTL15 and MEI1), and visual function (e.g., PANK2 and NMNAT2) in Guizhou black goat. CONCLUSION: Our results indicated that Guizhou black goat had a high level of genomic diversity and a low level of linkage disequilibrium in the whole genome. Selection signatures were detected in the genomic regions that were mainly related to growth and development, meat quality, reproduction, disease resistance, and humidity-cold resistance in Guizhou black goat. These results would provide a basis for further resource protection and breeding improvement of this very local breed.

Effects of Purple Corn Anthocyanin on Blood Biochemical Indexes, Ruminal Fluid Fermentation, and Rumen Microbiota in Goats.

The objective of this study was to observe the effects of anthocyanin from purple corn on blood biochemical indexes, ruminal fluid fermentation parameters, and the microbial population in goats. A total of 18 Qianbei Ma wether kids (body weight, 21.38 ± 1.61 kg; mean ± standard deviation) were randomly assigned to three groups using a completely randomized design. The group diets were: (1) control, basal diet, (2) treatment 1 (LA), basal diet with 0.5-g/d purple corn pigment (PCP), and (3) treatment 2 (HA), basal diet with 1-g/d PCP. The results showed that supplementation of PCP anthocyanin increased (P < 0.05) crude protein and gross energy digestibilities compared to the control. Compared to the control group, the inclusion of anthocyanin-rich PCP led to significantly increased (P < 0.05) plasma reduced glutathione and peroxidase concentrations. Goats receiving PCP had increased (P < 0.05) ruminal fluid acetic acid and a higher ratio of acetate to propionate, while the propionic acid, butyric acid, valeric acid, isobutyric acid, and isovaleric acid levels had decreased (P < 0.05). There was no significant difference (P > 0.05) in ruminal fluid alpha bacterial diversity among the three groups. At the phylum level, the feeding of PCP had significant effect (P < 0.05) on the abundances of Actinobacteriota, Proteobacteria, Elusimicrobiota, WPS-2, and Cyanobacteria. At the genus level, HA group had lower (P < 0.05) Prevotellaceae_NK3B31_group abundance compared to the other groups. In addition, significant differences (P < 0.05) were also observed for the ruminal fluid Eubacterium_nodatum_group, Amnipila, Ruminiclostridium, U29-B03, unclassified_c_Clostridia, Pyramidobacter, Anaeroplasma, UCG-004, Atopobium, norank_f_norank_o_Bradymonadales, Elusimicrobium, norank_f_norank_o_norank_c_norank_p_WPS-2, norank_f_Bacteroidales_UCG-001, and norank_f_norank_o_Gastranaerophilales among all groups. Taken together, the inclusion of anthocyanin-rich PCP increased the antioxidant potential, improved rumen volatile fatty acids, and induced a shift in the structure and relative abundance of ruminal microbiota in growing goats.