The aim of this study was to investigate the reversibility and safety of KISS1 metastasis suppressor (KISS1) gene vaccine in immunocastration. Six eight-week old ram lambs were randomly divided into vaccinated and control groups. The vaccine (1 mg/ram lamb) was injected at weeks 0, 3, and 6 of the study. Blood samples were collected from the jugular vein before primary immunization and at weeks 2, 4, 6, 10, 14, 22, and 30 after primary immunization. All ram lambs were slaughtered at 38 weeks of age, and samples were collected. The specific anti-KISS1 antibody titers in vaccinated animals were significantly higher and the serum testosterone level was significantly lower than those in the control groups from week 4 to 14 after primary immunization (p<0.05). No significant difference was observed at weeks 22 and 30 after the primary immunization. Similar results were also found for scrotal circumference, testicular weight, length, breadth, and spermatogenesis in seminiferous tubules in week 30 after primary immunization. KS (KISS1-hepatitis B surface antigen S) fusion fragment of KISS1 gene vaccine was not detected in host cell genomic DNA of 9 tissues of the vaccinated ram lambs by polymerase chain reaction. The effects of KISS1 gene vaccine in immunocastration were reversible and no integration events were recorded.

The follicle development (FD) is an important factor determining litter size in animals. Recent studies have found that noncoding RNAs (ncRNAs) play an important role in FD. In particular, the role of the regulatory mechanism of competing endogenous RNAs (ceRNAs) that drive FD has attracted increasing attention. Therefore, this study explored the genetic basis of goat FD by obtaining the complete follicular transcriptome of Dazu black goats at different developmental stages. Results revealed that 128 messenger RNAs (mRNAs), 4 long noncoding RNAs (lncRNAs), 49 microRNAs (miRNAs), and 290 circular RNAs (circRNAs) were significantly differentially expressed (DE) between large and small follicles. Moreover, DEmRNAs were enriched in many signaling pathways related to FD, as well as GO terms related to molecular binding and enzyme activity. Based on the analysis of the ceRNA network (CRN), 34 nodes (1 DElncRNAs, 10 DEcircRNAs, 14 DEmiRNAs, and 9 DEmRNAs) and 35 interactions (17 DEcircRNAs–DEmRNAs, 2 DElncRNAs–DEmiRNAs, and 16 DEmRNA–DEmiRNAs) implied that the CRN could be involved in the FD of goats. In conclusion, we described gene regulation by DERNAs and lncRNA/circRNA–miRNA–mRNA CRNs in the FD of goats. This study provided insights into the genetic basis of FD in precise transcriptional regulation.

How multiple ovulations happen in prolific goats is still unknown even though studies on ovarian physiology and folliculogenesis have made extensive progress. MicroRNAs (miRNAs) are a class of endogenous regulatory factors and regulate structural gene expression mainly at the post-transcriptional level. In this study, in the follicular phase, six large follicles were collected from prolific Dazu black goat and used to generate RNA libraries for RNA sequencing. Based on the litter size and average number of ovulatory follicles in Dazu black goats, the largest three follicles were sorted as ovulatory follicles, and the remaining as subordinate ones. In total, 418 known miRNAs and 110 novel miRNAs were found, and the expression of six randomly selected miRNAs was validated by quantitative PCR analysis. Nine miRNAs were differently expressed between the ovulatory and subordinate follicles (p < 0.01). Chi-miR-582-5p, novel-130, chi-miR-214-3p, and chi-miR-500-5p were upregulated in the ovulatory group, and chi-miR-383, chi-miR-130b-5p, chi-miR-92a-3p, chi-miR-125b-5p, and novel-9 were downregulated in the same group. Chi-miR-130b-5p and chi-miR-214-3p were predicted to target at LHR (XM_013967581.1), GDF9 (NM_001285708.1), BMP15 (NM_001285588.1), and CYP19A1 (XM_013967046.1). In conclusion, nine miRNAs were differently expressed between ovulatory and subordinate follicles, and chi-miR-130b-5p and chi-miR-214-3p were predicted to regulate the expression of genes involved in gonadotropin hormone signaling and oocyte-derived growth factors. Additional studies are needed to confirm these findings.

Natural selection and artificial breeding are crucial methods for developing new animal groups. The Baiyu black goats and Chuanzhong black goats are indigenous goat breeds from distinct ecological regions in Sichuan Province, with dramatically different growth and reproductivity. This study aimed to systematically elucidate the differences in production performance and genetic traits between Baiyu black goats and Chuanzhong black goats. We quantified growth and reproductive attributes for both breeds. Furthermore, we conducted a comprehensive analysis of genetic diversity, population structure, and selection signatures using whole-genome resequencing data. This dataset included 30 individuals from the Baiyu black goat breed, 41 from the Chuanzhong black goat breed, and an additional 59 individuals representing Chengdu grey goats, Tibetan cashmere goats, and Jianchang black goats, totaling 130 individuals across five goat breeds. The comparative analysis of production performance revealed that the weight and body size of Chuanzhong black goats were significantly higher than those of Baiyu black goats (p < 0.01). At the same time, the average kidding rate and kid-weaning survival rate of Chuanzhong black goats were also notably superior to those of Baiyu black goats (p < 0.01). The Baiyu black goats exhibited a more abundant genetic diversity and distinct genetic differences compared to the Chuanzhong black goat, according to an analysis grounded on genomic variation. The Baiyu black goats are more closely related to Tibetan cashmere goats, whereas Chuanzhong black goats share a closer genetic relationship with Chengdu grey goats. Additionally, we employed the π, Fst, and XP-EHH methodologies to identify genes related to immunity (TRIM10, TRIM15, TRIM26, and TRIM5), neurodevelopment (FOXD4L1, PCDHB14, PCDHB4, PCDHB5, PCDHB6, and PCDHB7), reproduction (BTNL2 and GABBR1), body size (NCAPG, IBSP, and MKNK1), and meat quality traits (SUCLG2 and PGM5). These results provide a theoretical basis for further resource conservation and breeding improvement of the Baiyu black goat and Chuanzhong black goat.