scholarly journals The effect of vitamin and mineral supplements on infection of pigs with porcine transmissible gastroenteritis

Author(s):  
V.N. Laskavyy ◽  
V.V. Laskavaya ◽  
T.I. Polyanina

The article describes studies to study the effect of vitamin and mineral supplements (VMS) on the survival of piglets with porcine transmissible gastroenteritis (TGS). The studies were carried out on animals of different age groups on the basis of pig breeding complexes with 2- and 3-phase systems of keeping, in farms disadvantaged by TGS. Studies have shown that in case of TGS, the abolition of VMS in the rearing groups can contribute to both a decrease and an increase in piglet mortality. There is a direct dependence of their death on the number of viruses in the external environment. A significant decrease in the mortality of piglets after stopping the intake of vitamins in comparison with control animals, in which VMS was not canceled, was proved. Shown is the effect of VMS on the survival rate of the livestock, depending on the system of keeping animals. With a 2-phase system of keeping, when the virus is constantly circulating in the room, the abolition of VMS provides a decrease in the mortality of piglets, and with a 3-phase systemof keeping, where the virus is periodically destroyed during the sanitization of premises before the next settlement, the abolition of VMS contributes small increase in piglet death. These data indicate a positive effect of the use of vitamins in the absence of the pathogen, and in the presence of it, the use of vitamins, on the contrary, enhances the development of the disease, which is fully consistent with studies on the reproduction of the virus in cell culture, when the addition of VMS to the growth medium stimulated the reproduction of the virus.

2013 ◽  
Vol 8 (3) ◽  
pp. 352-362 ◽  
Author(s):  
Paula A. J. Rosa ◽  
Ana M. Azevedo ◽  
S. Sommerfeld ◽  
Martina Mutter ◽  
Werner Bäcker ◽  
...  

Author(s):  
V.N. Laskavyy ◽  
T.I. Polyanina ◽  
V.V. Laskavaya ◽  
V.T. Nochevny

The article describes studies on the effect of vitamin and mineral supplements (VMS) on the replication of coronavirus in tissue culture. The cytopathic effect of the porcine transmissible gastroenteritis virus (strain TO36SD192 (Japan) and the vaccine strain "RIMS" was studied on the SPEV cell line in the presence of mineral and vitamin supplements (VMS) with an increased content of vitamins A and D. The results of the study showed that the introduction of vitamin and mineral supplements into the growth medium provides an increase in the yield of the RIMS virus by 16.7 - 23%. Interestingly, at the minimum infectious dose, the presence or absence of VMS does not in any way affect the titer of the virus of the reference strain of the coronavirus TO36SD192. However, an increase in the infectious dose by only one order of magnitude (1000 TDC50 / ml) stimulates an increase in the virus titer by 22.5% in the presence of VMS. With the addition of VMS, the RIMS strain reproduced more actively and the virus titer in the experiment with the addition of VMS was 30% higher than in the control (without VMS). A further increase in the infectious dose showed a significant increase in the virus titer from 13.4% to 6.25%. It should be noted that the TO36SD192 virus, well adapted to the SPEV culture, can be compared with viruses that cause seasonal ARVI in humans, which are also well adapted in the human body, and the use of VMS during the peak of the epidemic can stimulate viral replication. Since the RIMS strain virus is poorly adapted to the SPEV culture, its action can be compared with a virus that has entered the human population, for example, SARS-CoV-2. This means that taking vitamins at any infectious dose (during an epidemic) will stimulate the disease.


2014 ◽  
Vol 30 (4) ◽  
pp. 542-546 ◽  
Author(s):  
Dennis E. Anderson ◽  
Christopher T. Franck ◽  
Michael L. Madigan

The effects of gait speed and step length on the required coefficient of friction (COF) confound the investigation of age-related differences in required COF. The goals of this study were to investigate whether age differences in required COF during self-selected gait persist when experimentally-controlling speed and step length, and to determine the independent effects of speed and step length on required COF. Ten young and 10 older healthy adults performed gait trials under five gait conditions: self-selected, slow and fast speeds without controlling step length, and slow and fast speeds while controlling step length. During self-selected gait, older adults walked with shorter step lengths and exhibited a lower required COF. Older adults also exhibited a lower required COF when walking at a controlled speed without controlling step length. When both age groups walked with the same speed and step length, no age difference in required COF was found. Thus, speed and step length can have a large influence on studies investigating age-related differences in required COF. It was also found that speed and step length have independent and opposite effects on required COF, with step length having a strong positive effect on required COF, and speed having a weaker negative effect.


2020 ◽  
Vol 117 (42) ◽  
pp. 25982-25984
Author(s):  
Rainer Kotschy ◽  
Patricio Suarez Urtaza ◽  
Uwe Sunde

The demographic dividend has long been viewed as an important factor for economic development and provided a rationale for policies aiming at a more balanced age structure through birth control and family planning. Assessing the relative importance of age structure and increases in human capital, recent work has argued that the demographic dividend is related to education and has suggested a dominance of improving education over age structure. Here we reconsider the empirical relevance of shifts in the age distribution for development for a panel of 159 countries over the period 1950 to 2015. Based on a flexible model of age-structured human capital endowments, the results document important interactions between age structure and human capital endowments, suggesting that arguments of clear dominance of education over age structure are unwarranted and lead to potentially misleading policy conclusions. An increase in the working-age population share has a strong and significant positive effect on growth, even conditional on human capital, in line with the conventional notion of a demographic dividend. An increase in human capital only has positive growth effects if combined with a suitable age structure. An increasing share of the most productive age groups has an additional positive effect on economic performance. Finally, the results show considerable heterogeneity in the effect of age structure and human capital for different levels of development. Successful policies for sustainable development should take this heterogeneity into account to avoid detrimental implications of a unidimensional focus on human capital without accounting for demography.


1965 ◽  
Vol 16 (6) ◽  
pp. 981 ◽  
Author(s):  
J Lax ◽  
Turner H Newton

The influence of sex, strain, location, and age of ewe on survival rate to weaning of single-born Merino lambs has been examined in two sets of data: the strain trial, involving five strains run without selection at each of three locations (Cunnamulla, Qld.; Armidale, on the northern tablelands of New South Wales; Deniliquin, in the Riverina area of New South Wales), with six age groups of ewes; and the same five strains later included in selection groups at Armidale with seven age groups of ewes. The strain trial at Armidale ran mainly on native, and the selection groups mainly on improved pastures. Female lambs had a higher survival rate than either castrated or entire males, the differences in lambs weaned per lamb born being 0.03 and 0.04 respectively. No strain differences could be regarded as statistically significant, and neither could the strain x location interaction in the strain trial. Mean survival rates for the strains ranged from 0.673 to 0.786 on the Armidale native and from 0.802 to 0.850 on the Armidale improved pasture, from 0.746 to 0.859 at Cunnamulla, and from 0.838 to 0.894 at Deniliquin. The strains did not rank consistently in the same order. Location had a marked effect on survival rate, the means being 0.744 for the native and 0.824 for the improved pasture at Armidale, 0.810 at Cunnamulla, and 0.868 at Deniliquin. Age of ewe had a marked influence in the poorest environment (Armidale native pasture), survival rate rising with age and later falling sharply. The effect was less marked in the intermediate environments (Armidale improved pasture and Cunnamulla) and negligible at Deniliquin. The patterns at Cunnamulla and Deniliquin are confirmed by data from other experiments on these stations. Survival rate is one component of number of lambs weaned. The other component, number of lambs born, has a higher mean value at Deniliquin than Cunnamulla, but shows a strong association with age of ewe in both environments. Number of lambs born responds rapidly to selection, but no information is yet available concerning the likely response in survival rate. If improvement in environment can raise the survival rate, particularly in the youngest and oldest ewes, then selection for number of lambs born, combined with improved environment, should lead to a marked rise in the number of lambs weaned.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Elina Kallas ◽  
Eve Parts

Purpose The present paper aims to identify a set of cognitive and contextual characteristics that explain entrepreneurial intentions, actions and venture creation, thereby covering three successive stages of becoming an entrepreneur. Design/methodology/approach The analysis is based on entrepreneurship data from a self-reported online survey (n = 1,492) gathered among the Estonian population in 2017. The authors use an exploratory factor analysis to reduce initial survey responses about the external environment into latent factors. Linear regression models are applied to predict the determinants of entrepreneurial intention and actions, whereas the logit model is applied to find out the determinants of being or not being an entrepreneur. Findings Younger people, respondents with vocational education and the unemployed have a higher intention to start up. Men are more active than women in the second stage of taking real action, whereas middle-aged respondents and managers are less active. In the final stage of enterprise creation, men become more likely entrepreneurs, whereas younger people and those who do not have higher education become less likely entrepreneurs. Entrepreneurial attitudes and competencies as preconditional factors of entrepreneurial readiness have a positive effect in all three stages. The role of motivation appeared to be controversial – it has a weak positive effect on the intention stage but a strong negative effect on the action stage, becoming insignificant in the final stage of becoming an entrepreneur. In the final stage, taking real action has the strongest positive effect. Regarding differences between entrepreneurs and non-entrepreneurs, entrepreneurs have a more positive perception of the business environment and the ease of doing business, including the simplicity of entrepreneurship-related legislation. On the other hand, entrepreneurs are more skeptical about the availability of financial resources, and they perceive public attitudes and the role of entrepreneurs in a society less positively. Research limitations/implications As data of this study originates from a survey, the sample may not represent the whole population. This might limit the extent to which the conclusions of this study can be generalized. Also, the study’s data do not enable us to consider all potential factors that may affect entrepreneurial intention, action and venture creation. For example, the authors do not consider the effect of income or differences between opportunity and necessity entrepreneurship because of data limitations. Practical implications This study focuses on environmental obstacles and individual restrictions that are important in different stages of becoming an entrepreneur. In terms of policy implications, providing better financing opportunities both from private and public institutions and keeping entrepreneurship legislation simple and transparent have the utmost importance in increasing the share of entrepreneurs and entrepreneurship-related benefits in society. The younger population’s high entrepreneurial intentions should be transferred more effectively into real actions toward starting up, paired with supportive entrepreneurship education. Social implications The study results show that developing positive attitudes towards entrepreneurship and providing relevant competencies through the education system are relevant factors in all stages of becoming an entrepreneur, thus enabling entrepreneurial activities in society. Originality/value First, the authors investigate the factors of entrepreneurship separately during the three stages in the journey of becoming an entrepreneur, starting from intentions, followed by preparation actions and finalized by real enterprise creation. Second, the analysis of this study is based on the original Environment-Readiness Entrepreneurship Intention model, which emphasizes the role of the external environment in entrepreneurial processes. Ten factors of the external environment are extracted using exploratory analysis instead of using three traditional predefined factors of the economic, political and socio-cultural environment. Third, our focus on Estonia broadens the knowledge about entrepreneurship in the Central and Eastern European region in general and in the Baltic region, more specifically.


2011 ◽  
Vol 57 (No. 5) ◽  
pp. 200-209 ◽  
Author(s):  
I. Kuneš ◽  
T. Koňasová ◽  
V. Balcar ◽  
M. Baláš ◽  
D. Zahradník ◽  
...  

An experiment with seedlings of Alnus viridis was established on a clear-felled tract situated on a summit tableland of the Jizerské hory Mts. (central Europe, Czech Republic) at an altitude of 980 m a.s.l. The aims of the experiment were (i) to evaluate the response of A. viridis to the application of a basic mixture containing crushed limestone and amphibolite and (ii) to assess the growth potential of the species in a poor acidic site under climatically harsh conditions. Alnus viridis showed a good growth performance and survival rate, its initial response to fertilization was positive. The height growth and expansion of crowns were slightly but significantly stimulated by the treatment, the survival rate was also increased, though not significantly. The amendment application temporarily increased the foliar Ca and Mg concentrations. The content of foliar P, of the most deficient macroelement, was not improved by the treatment. However, the positive effect of fertilization was short-lasting and unconvincing from the aspect of practical use. In the second half of the reference period the control started to gain on the fertilized variant and as for mean height and crown diameter, both variants got almost equalized eight growing seasons after the treatment.


2017 ◽  
Vol 92 (7) ◽  
pp. 1690-1698 ◽  
Author(s):  
Halina Murasiewicz ◽  
Alvin W Nienow ◽  
Mariana P Hanga ◽  
Karen Coopman ◽  
Christopher J Hewitt ◽  
...  
Keyword(s):  
A Cell ◽  

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