Tong Huili

Contents of Trace Metal Elements in Cow Milk Impacted by Different Feedstuffs

Abstract Feedstuff intake plays key role in impacting the yield and quality of milk. In this study, we discussed the contents of trace metal elements in cow milk impacted by different feedstuffs. We detected the contents of Pb, Cd, As, Cu, Mg, Ca, Fe and Zn in different feedstuffs and milk by atomic absorption spectrophotometry. The determinations of Pb, Cd and As contents were by graphite furnace AAS and Cu, Mg, Ca, Fe and Zn was by flame atomic absorption spectrometry. The results showed that Pb, Cd, As and Cu presented in feedstuffs, but Pb, Cd and As were lowly detected in milk samples, and Cu was not detected in milk samples. The content of Mg in concentrates was lower than that in forages. However, the content of Mg in milk from concentrate feed was higher than that in forage feed. This suggested that the utilization of Mg in concentrate feed was higher than that in forage feed. The contents of Ca and Zn were opposite to Mg, and the utilization of Ca and Zn in forage feed was higher than that in concentrate feed. There was no obviously change law of Fe in different feedstuffs and milk samples. The relationship between the contents of trace metal elements in milk to feedstuffs would provide a theoretical basis for dairy farming. It would be useful for improving the milk yield and milk quality of dairy production.

Effect of MSTN Propeptide and shRNA Co-expression Vector on Proliferation of Skeletal Muscle Satellite Cells

Abstract Myostatin (MSTN) is a negative regulator of skeletal muscle growth, in order to study the effect of inhibition MSTN expression on the proliferation of bovine skeletal muscle satellite cells, we constructed co-expression vector pcDNA3.1-Pro-MSTNshRNA, transfected it into muscle satellite cells by Liposome 2000, and detected cell proliferation changes by CCK-8 method and flow cytometry after 48 h. The expressions of P21 and CDK2 were detected by Western blot and real-time PCR. The results showed that the cell vitality of experimental groups significantly increased than that of the negative control, and cells in S phase also increased significantly (P

Vaccaria segetalis activates cellular lactogenesis signaling pathway of dairy cow mammary epithelial cells in vitro

Vaccaria segetalis has very strong effect on lactogenesis, but the mechanism is still unknown. This study aims to reveal the influence of Vaccaria segetalis on cellular lactogenesis signaling pathway of dairy cow mammary epithelial cells (DCMECs). In this study the purified DCMECs was used to screen the most effective concentration of Vaccaria segetalis water decoction for lactogenesis. DCMECs were treated with prolactin (PRL), E (estrogen) or water extraction of Vaccaria segetalis, and many lactogenesis signal molecules in DCMECs including prolactin receptor (PRLR), estrogen receptor a (ERa), p-STAT5, p-mTOR, p100, GARS, PPARg and cyclinD1 were detected by using western blot assay. It was found that Vaccaria segetalis, E and PRL could promote lactogenesis of DCMECs and up-regulate these lactogenesis signal molecules except PPARg. These data reveals that Vaccaria segetalis has a similar role as E or PRL and activates cellular lactogenesis signaling pathway of DCMECs on both the translational and transcriptional levels.

Impact of Bovine Skeletal Muscle Satellite Cell Differentiation by Small Interfering RNA Targeting Myogenin Gene

To examine the effect of myogenin gene on the differentiation of bovine skeletal muscle satellite cell, we constructed small interfering RNA plasmid vector to obtain myogenin knockdown bovine skeletal muscle cells, then used cell transfection, real time RCR and Western Blot to detect the influence of myogenin to cell differentiation. Results showed that the knockdown of myogenin significantly decreased its expression and other muscle-specific genes. Compared to the control, it could differentiate into few myotubes when challenged by low serum in the medium. These findings provided an important theoretical basis for further explore of the genetic mechanism in adult skeletal muscle, the remedy of muscle injuries and the cultivation of high-yield transgenic cattle.