METHODS: We classified camels (fourth parity) as low- or high-yield, examined pregnant camels using B-mode ultrasonography, observed the microscopic changes in the mammary gland using hematoxylin and eosin (HE) staining, and used RNA sequencing to identify differentially expressed genes (DEGs) and pathways.
RESULTS: The average standard milk yield over the 300 days during parity was recorded as 470.18 ± 9.75 and 978.34 ± 3.80 kg in low- and high-performance camels, respectively. Nine female Junggar Bactrian camels were subjected to transcriptome sequencing, and 609 and 393 DEGs were identified in the low-yield vs. high-yield (WDL vs. WGH) and pregnancy versus colostrum period (RSQ vs. CRQ) comparison groups, respectively. The DEGs were compared with genes associated with milk production traits in the Animal Quantitative Trait Loci database and in Alashan Bactrian camels, and 65 and 46 overlapping candidate genes were obtained, respectively. Functional enrichment and protein-protein interaction network analyses of the DEGs and candidate genes were conducted. After comparing our results with those of other livestock studies, we identified 16 signaling pathways and 27 core candidate genes associated with maternal parturition, estrogen regulation, initiation of lactation, and milk production traits. The pathways suggest that emerged milk production involves the regulation of multiple complex metabolic and cellular developmental processes in camels. Finally, the RNA sequencing results were validated using quantitative real-time PCR; the 15 selected genes exhibited consistent expression changes.
CONCLUSIONS: This study identified DEGs and metabolic pathways affecting maternal parturition and milk production traits. The results provides a theoretical foundation for further research on the molecular mechanism of genes related to milk production traits in camels. Furthermore, these findings will help improve breeding strategies to achieve the desired milk yield in camels.
方法:我们将骆驼(第四平价)分类为低收益或高收益,用B超检查怀孕的骆驼,用苏木精和伊红(HE)染色观察乳腺的微观变化,并使用RNA测序来鉴定差异表达基因(DEGs)和途径。
结果:在低性能和高性能骆驼中,平价期间300天内的平均标准产奶量分别为470.18±9.75和978.34±3.80千克,分别。九只雌性准噶尔双峰骆驼进行了转录组测序,在低产量和低产量中确定了609和393个DEG。高产量(WDL与WGH)和妊娠期与初乳期(RSQ与CRQ)比较组,分别。在动物数量性状基因座数据库和阿拉善双峰骆驼中,将DEGs与与产奶性状相关的基因进行了比较,获得了65个和46个重叠的候选基因,分别。进行了DEGs和候选基因的功能富集和蛋白质-蛋白质相互作用网络分析。在将我们的结果与其他牲畜研究的结果进行比较后,我们确定了16个信号通路和27个核心候选基因与产妇分娩相关,雌激素调节,开始泌乳,和产奶性状。这些途径表明,出现的牛奶生产涉及骆驼中多种复杂的代谢和细胞发育过程的调节。最后,使用定量实时PCR验证RNA测序结果;选择的15个基因表现出一致的表达变化。
结论:本研究确定了影响产妇分娩和产奶性状的DEG和代谢途径。研究结果为进一步研究骆驼产奶性状相关基因的分子机制提供了理论基础。此外,这些发现将有助于改善育种策略,以实现骆驼所需的产奶量。