RESUMO
The purpose of the present study was to investigate the effects of different levels of a Chinese herbal medicine formulation combined with JM113 (CHM-JM113) on growth performance, antioxidant capacity, organ index, and intestinal health of AA broilers. The AA broiler chicks were randomly allocated to 5 treatments as follows: a basic diet for the control group, the basic diet supplemented with 0.25% CHM-JM113, 0.5% CHM-JM113, 1% CHM-JM113 and 2% CHM-JM113 for the treatment group, respectively. The results showed that the addition of CHM-JM113 to the diet significantly reduced the mortality (p < 0.01) and improved the European Broiler Index (EBI) (p < 0.05), whereas it had no significance on growth performance of AA broilers (p > 0.05). Comparing the control group, 0.5 and 1% CHM-JM113 group significantly improved the organ index of liver, spleen and bursa (p < 0.05). In terms of intestinal morphology and structure, the addition of different levels of CHM-JM113 increased VH and VH/CD ratio, decreased CD in the small intestine compared to the control group, with 1 and 2% of the additive dose being more effective (p < 0.05). Chinese herbal medicine and probiotics as natural antioxidants also significantly increased the content of SOD in serum of 21-day-old broilers (p < 0.01), and significantly decreased the content of MDA in serum (p < 0.01). At 42 days of age, the addition of 1 and 2% CHM-JM113 significantly increased the content of SOD (p < 0.01) and significantly decreased the content of MDA in the organism (p < 0.01), accompanied by a significant increase in T-AOC and CAT content. In the study of the effect of CHM-JM113 on intestinal immunity, compared with the control group, we found that 1% or 2% CHM-JM113 had a better effect on the expression of occludin and claudin-1 in the intestinal segments of broilers (p < 0.05). For the expression of GATA-3, 0.5% CHM-JM113 may have a better effect (p < 0.05). CHM-JM113 may be used as an antibiotic alternative in broiler production.
RESUMO
Involving oxygen in the traditional chemical vapor deposition (CVD) process has proven a promising approach to achieve large-scale graphene single crystals (GSCs), but its many relevant fundamental aspects are still not fully understood. Here we report a systematic study on the role of hydrogen in the growth of millimeter-sized GSCs using enclosure-like Cu structures via the oxygen-assisted CVD process. Results show that GSCs have different first layer growth behaviors on the inside and outside surfaces of a Cu enclosure when the H2 environment is varied, and these behaviors will consequently and strongly influence the adlayer formation in these GSCs, leading to two entirely different growth modes. Low H2 partial pressure (PH2) tends to result in fast growth of dendritically shaped GSCs with multiple small adlayers, but high PH2 can modify the GSC shape into hexagons with single large adlayer nuclei. This difference of adlayers is attributed to the different C diffusion paths determined by the shapes of their host GSCs. On the basis of these observations, we developed an isothermal two-step method to obtain GSCs with significantly improved growth rate and sample quality, in which low PH2 is first set to accelerate the growth rate followed by high PH2 to restrict the adlayer nuclei. Our results prove that the growth of GSCs can reach a reasonable optimization between their growth rates and sample quality by simply adjusting the CVD H2 environment, which we believe will lead to more improvements in graphene synthesis and fundamental insight into the related growth mechanisms.
