Effects of a multi-strain probiotic on growth, health, and fecal bacterial flora of neonatal dairy calves

Guo Yongqing,Li Zheng,Deng Ming,Li Yaokun,Liu Guangbin,Liu Dewu,Liu Qihong,Liu Qingshen,Sun Baoli 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.2

Objective: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life. Methods: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day. Results: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058). Conclusion: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions. Objective: The aim of this study was to investigate the effects of dietary supplementation with a multi-strain probiotic (MSP) product containing of Bifidobacterium animalis, Lactobacillus casei, Streptococcus faecalis, and Bacillus cerevisiae on growth, health, and fecal bacterial composition of dairy calves during the first month of life.Methods: Forty Holstein calves (24 female and 16 male) at 2 d of age were grouped by sex and date of birth then randomly assigned to 1 of 4 treatments: milk replacer supplementation with 0 g (0MSP), 2 g (2MSP), 4 g (4MSP), and 6 g (6MSP) MSP per calf per day.Results: Supplementation of MSP did not result in any significant differences in parameters of body measurements of calves during the 30 d period. As the dosage of MSP increased, the average daily gain (p = 0.025) and total dry matter intake (p = 0.020) of calves showed a linear increase. The fecal consistency index of the 2MSP, 4MSP, and 6MSP group calves were lower than that of the 0MSP group calves (p = 0.003). As the dosage of MSP increased, the concentrations of lactate dehydrogenase (p = 0.068) and aspartate aminotransferase (p = 0.081) in serum tended to decrease, whereas the concentration of total cholesterol increased quadratically (p = 0.021). The relative abundance of Dorea in feces was lower (p = 0.011) in the 2MSP, 4MSP, and 6MSP group calves than that in the 0MSP group calves. The relative abundance of Dorea (p = 0.001), Faecalibacterium (p = 0.050), and Mitsuokella (p = 0.030) decreased linearly, whereas the relative abundance of Prevotella tended to increase linearly as the dosage of MSP increased (p = 0.058).Conclusion: The MSP product can be used to reduce the diarrhea, improve the performance, and alter the composition of the fecal bacteria in neonatal dairy calves under the commercial conditions.

Nonlinear dynamics of a two-stage planetary gear system with sliding friction and elastic continuum ring gear

Wei Liu,Kai Shi,Valerii Tupolev,Guangbin Yu,Bing Dai 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.1

In this paper, nonlinear dynamics of two-stage planetary gear (TSPG) system with elastic ring gear and sliding friction are studied to extend previous study. Compared with the present literatures, the majority of previous works modeled ring gear as a rigid body and completely ignored the sliding friction. This study mainly focus on the investigation of the effect of sliding friction and ring’s elasticity on the nonlinear behavior through the previous elastic TSPG model. Time-varying mesh stiffness formulas including sliding friction and nonlinearity backlash are derived to compare the bifurcation diagrams and vibration response. Numerical examples show interesting behaviors for the TSPG model including sliding friction and elastic component in comparison with the lumped parameter model.

Guaranteed-performance Consensualization for High-order Multi-agent Systems with Intermittent Communications

Le Wang,Qing Chen,Jianxiang Xi,Guangbin Liu 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.5

The current paper studies the guaranteed-performance consensualization for general high-order multiagentsystems with intermittent communications. Firstly, a new consensus protocol is constructed by using only intermittentlocal information, and the corresponding performance function is given to guarantee the consensus regulationperformance among neighboring agents. Then, linear matrix inequality conditions for guaranteed-performanceconsensus and consensualization are respectively provided and a guaranteed-performance cost of multi-agent systemsis determined meanwhile. Furthermore, the whole motion mode of the multi-agent system can be described byderiving a precise expression of the consensus function. If the nominal converge rate is larger than a positive threshold,then multi-agent systems can achieve guaranteed-performance consensus by determining the gain matrix whenintermittent communications are involved, and the performance function is less than the guaranteed-performancecost. Finally, a simulation example is shown to demonstrate the effectiveness of the proposed theorems.

Adaptive Consensualization for Lipschitz Nonlinear-type Multi-agent Networks with Fixed Topologies

Tang Zheng,Jianxiang Xi,Mei Yuan,Guangbin Liu 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

Adaptive consensualization problems for Lipschitz nonlinear-type multi-agent networks with fixed topologies are addressed. By using the state errors of the neighboring agents, an adaptive consensus protocol is proposed to deal with the consensualization problems. To eliminate the impacts of the Lipschitz nonlinear dynamics, the structure property of a transformation matrix and the Laplacian matrix, and the Lipschitz condition are well utilized. In the Lyapunov function, a scaling constant is introduced to eliminate the impacts of eigenvalues of the Laplacian matrix, which are the global information of the whole multi-agent networks. Then, an completely distributed consensualization criterion is presented in terms of the linear matrix inequality. Furthermore, an explicit expression of the consensus function and its initial state of this multi-agent network are presented. In the Final, a numerical example is shown to verify the validity of theoretical results.

Effects of inlet working condition and heat load on supercritical CO2 compressor performance

Pei Jinze,Zhao Yuanyang,Zhao Mingran,Liu Guangbin,Yang Qichao,Li Liansheng 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.8

The supercritical carbon dioxide (sCO2) Brayton power cycle is more effective than the conventional power cycle and is more widely applicable to heat sources. The inlet working conditions of the compressor have a higher influence on their operating performance because the thermophysical properties of the CO2 vary dramatically close to the critical point. The flow in the sCO2 compressor is simulated and the compressor performance is analyzed. The results show that the sCO2 centrifugal compressor operates outside of its intended parameters due to the change in inlet temperature. The sCO2 compressor requires more power as the inlet temperature increases. The compressor power is 582 kW when the inlet temperature is at 304 K. But the power is doubled when the inlet temperature increases to 314 K, and the change in the isentropic efficiency is within 5%. The increase in the inlet temperature significantly reduces the risk of condensation in centrifugal compressors. When the heat load of the sCO2 power system changes, the inlet pressure to the turbine can be kept constant by regulating the rotational speed of compressors. With the increase in rotational speed, the incidence loss and condensation risk increase