Effects of disodium fumarate on ruminal fermentation and microbial communities in sheep fed on high-forage diets.

This study was conducted to investigate effects of disodium fumarate (DF) on fermentation characteristics and microbial populations in the rumen of Hu sheep fed on high-forage diets. Two complementary feeding trials were conducted. In Trial 1, six Hu sheep fitted with ruminal cannulae were randomly allocated to a 2 × 2 cross-over design involving dietary treatments of either 0 or 20 g DF daily. Total DNA was extracted from the fluid- and solid-associated rumen microbes, respectively. Numbers of 16S rDNA gene copies associated with rumen methanogens and bacteria, and 18S rDNA gene copies associated with rumen protozoa and fungi were measured using real-time PCR, and expressed as proportion of total rumen bacteria 16S rDNA. Ruminal pH decreased in the DF group compared with the control (P < 0.05). Total volatile fatty acids increased (P < 0.001), but butyrate decreased (P < 0.01). Addition of DF inhibited the growth of methanogens, protozoa, fungi and Ruminococcus flavefaciens in fluid samples. Both Ruminococcus albus and Butyrivibrio fibrisolvens populations increased (P < 0.001) in particle-associated samples. Trial 2 was conducted to investigate the adaptive response of rumen microbes to DF. Three cannulated sheep were fed on basal diet for 2 weeks and continuously for 4 weeks with supplementation of DF at a level of 20 g/day. Ruminal samples were collected every week to analyze fermentation parameters and microbial populations. No effects of DF were observed on pH, acetate and butyrate (P > 0.05). Populations of methanogens and R. flavefaciens decreased in the fluid samples (P < 0.001), whereas addition of DF stimulated the population of solid-associated Fibrobacter succinogenes. Population of R. albus increased in the 2nd to 4th week in fluid-associated samples and was threefold higher in the 4th week than control week in solid samples. Analysis of denaturing gradient gel electrophoresis fingerprints revealed that there were significant changes in rumen microbiota after adding DF. Ten of 15 clone sequences from cut-out bands appearing in both the 2nd and the 4th week were 94% to 100% similar to Prevotella-like bacteria, and four sequences showed 95% to 98% similarity to Selenomonas dianae. Another 15 sequences were obtained from bands, which appeared in the 4th week only. Thirteen of these 15 sequences showed 95% to 99% similarity to Clostridium sp., and the other two showed 95% and 100% similarity to Ruminococcus sp. In summary, the microorganisms positively responding to DF addition were the cellulolytic bacteria, R. albus, F. succinogenes and B. fibrisolvens as well as proteolytic bacteria, B. fibrisolvens, P. ruminicola and Clostridium sp.

[Effects of xueguantong on plasma endothelin and calcitonin gene-related peptide in quail atherosis model].

This paper mainly reported the antiatherogenic mechanism of action of Xueguantong on molecular level. After being established by feeding with high fat diet for 12 weeks, the quail atherosis models were given Xueguantong for 30 days. Then, determining their plasma endothelin and calcitonin gene-related peptide (CGRP) with radioimmunoassay (RIA) and observing the effects of Xueguantong on plasma endothelin and CGRP in quail atherosis models. Results showed that the plasma endothelin increased and CGRP decreased during quail atherosis formation. The plasma endothelin was decreased (P < 0.05) and CGRP was increased (P < 0.05) by using Xueguantong. It suggested that one of antiatherogenic mechanisms of Xueguantong was decreasing the endothelin and increasing the CGRP.

[Effect of yuxintong capsule on plasma endothelin and serum nitric oxide in acute myocardial ischemia dogs].

Effect of Yuxintong (YXT) capsule on plasma endothelin(ET), serum nitric oxide (NO) and creatine phosphokinase (CPK) activity in experimental acute myocardial ischemia dogs were observed. The results indicated that in acute myocardial ischemia dogs, the serum CPK activity and plasma ET level increased and serum NO level decreased significantly. In comparing with control, YXT not only could reduce significantly the increased plasma ET content and serum CPK activity, but also increase markedly the producing and releasing of NO, P < 0.05-0.001. Therefore, it could protect the myocardia from ischemic damage, the efficacy of YXT was positively dose dependent.

[Study of platelet aggregation affected by 8 classical recipes in rabbit].

Arachidonic acid can induce platelet aggregation in rabbits in vitro. The experimental model was designed to observe inhibitory effect of 8 classical recipes of activating blood circulation to remove the stasis on platelet aggregation in vitro. The results showed that each one of 8 classical recipes has inhibitory effect on platelet aggregation in vitro in various degree. Among them, Gexia Zhuyu Tang (GZT), Shentong Zhuyu Tang (SZT) and Shaofu Zhuyu Tang (SFZT) were more effective. The results suggested that inhibitory effect of platelet aggregation produced by 8 classical recipes might be one of mechanisms of blood stasis treatment.