Since 1940 molybdenum has been known as an essential trace element in plant nutrition and physiology. It has a central role in nitrogen metabolism, and its deficiency leads to nitrate accumulation in plants. In this study, we cultivated maize seedlings (Zea mays L. cv. Norma SC) in nutrient solution and soil (rhizoboxes) to investigate the effect of molybdenum treatment on the absorption of molybdenum, sulphur and iron. These elements have been previously shown to play important roles in nitrate reduction, because they are necessary for the function of the nitrate reductase enzyme. We also investigated the relationship between molybdenum treatments and different nitrogen forms in maize. Molybdenum treatments were 0, 0.96, 9.6 and 96 μg kg-1 in the nutrition solution experiments, and 0, 30, 90, 270 mg kg-1 in the rhizobox experiments. On the basis of our results, the increased Mo level produced higher plant available Mo concentration in nutrient solution and in soil, which resulted increased concentration of Mo in shoots and roots of maize seedlings. In addition it was observed that maize seedlings accumulated more molybdenum in their roots than in their shoots at all treatments. In contrast, molybdenum treatments did not affect significantly either iron or sulphur concentrations in the plant, even if these elements (Mo, S and Fe) play alike important roles in nitrogen metabolism. Furthermore, the physiological molybdenum level (1x Mo = 0.01 µM) reduced NO3-N and enhanced the NH4-N concentrations in seedlings, suggesting that nitrate reduction was more intense under a well-balanced molybdenum supply.
Studies have focused on identifying combinations of insects and organic waste to optimise bio-conversion. Here, the effects of different diets (10% chicken feed complemented with 90% vegetable waste, garden waste, cattle manure, or horse manure) on growth and survival rates, and nutritional value of Zophobas morio and Tenebrio molitor larvae, and Acheta domesticus were investigated. Compared with chicken feed, organic waste decreased the individual larval weight, although green waste showed fewer negative effects than the manure. The macronutrient concentrations in garden waste were moderate compared with chicken feed, and vegetable waste was the poorest diet in terms of nutrient concentration, as revealed by the principal component analysis (PCA). There was no difference in weight between larvae reared on garden waste and those reared on vegetable waste. Tenebrio molitor and A. domesticus showed the maximum growth rates at 71–101 and 36–66 days of age at 22.5 ± 2.5 °C, respectively. The PCA showed that the protein and fibre concentrations were inversely proportional to fat concentration in the larvae. Acheta domesticus was rich in proteins, whereas Z. morio and T. molitor were rich in fat. Feeding nutrient-poor diets resulted in a lower protein and a higher fat concentration in the larvae.
Abstract. The aim of the present study was to investigate the effect of liquid milk supplement on litter performance (weight development of the piglets, weaning weight and mortality) and on sow back-fat thickness change during the suckling period.Data were collected from 150 litters, with the weight of a total of 1709 piglets measured at birth, at 14 days of age and at weaning (28 days), respectively. Sow (n = 150) back-fat depth was measured the day before farrowing, 14 days after farrowing and at weaning. In the control group (n = 363), the piglets were suckled and got pre-starter feed from day 10. In the four experimental groups (MS1; MS2; MS2 and MS4; n = 1346), the piglets received additional milk replacer in various concentrations from the 10th day of life. While there were no significant differences in birth weight between the control and experimental groups, we did find significant differences between the 14-day weights and weaning weights. The milk supplement significantly reduced mortality compared to the control (11.6 vs. 4.9; 5.9, 8.9; 8.3 %). However, there were no statistically significant differences between litter homogeneity data, based on the CV% of piglet weight. Three experimental groups (MS1, MS2 and MS4) were more homogenous compared to the control group at weaning (25.3 vs. 20.9; 20.3; 20.3 CV%). Based on the examination of sow back-fat thickness reduction, there were significant differences between the control (C) and MS3 groups (7.61 vs. 5.57 mm reduction, P < 0.05) during the suckling period. These results demonstrate the advantage of milk replacer on weaning weight. Litter homogeneity, piglet mortality and back-fat thickness of the sows were affected by providing milk replacer to the piglets during the suckling period.
Based on Soil Plant Analysis Development (SPAD) values, nitrogen (N) deficiency, nutrient need, and the effect of fertilizer treatments on crop conditions can be quickly estimated, but the method of SPAD measurement significantly affects the accuracy of estimation. In field experiments near Debrecen, Hungary, we measured the reliability and accuracy of SPAD measurements in maize and potato populations using a Minolta SPAD-502 meter (Minolta, Tokyo, Japan). The aim of our study was to determine which SPAD measurement methods are capable of detecting small differences in the SPAD values. During the examination of maize ear leaves, we determined the distribution of SPAD values along the leaf blade and then identified single-and multipoint measurement methods. By comparing the results of the measurement methods we established that the single-point-based measurements are less suitable for the determination of the average SPAD value of the leaf blade than the multipoint-based measurements. Also, we showed that the increase in the number of measurement points does not influence the accuracy of the measurement in the case of systematic measurement methods based on the distribution of SPAD values. Thus we recommend five-point measurements to obtain the average SPAD values of the ear leaves: the tip of the leaf blade and at one quarter and one half of the leaf blade from the base on both the right and left sides. From the measurements conducted in potato, we showed that the SPAD values change at every foliar level and that the measurements carried out on the middle foliar level provide the closest correlation with the average SPAD values of the leaf canopy. Based on these results, we recommend making measurements at different foliar levels or on the middle foliar level to determine the average SPAD value of the potato leaf canopy.
The aim of this study was to compare the characteristics of the productive lifetime (plT) of sows kept on two farms, from the aspect of reasons for culling. The study was based on data from animals from two breeding farms in hungary, using the data of 3493 crossbred dutch large white and dutch landrace sows (dlw × DL) between their first farrowing until the time of culling (2006 and 2012). For six years, the annual culling rate for both farms averaged 45%. The most frequent reasons for removal on both farms were reproductive problems (40%, 51%), leg problems (29%, 23%) and mortality (19%, 15%). There was a significant difference between the distributions of reasons for culling on the two farms (χ 2 =41.7, P≤0.001). The distributions of reasons for culling differed in three periods of sow breeding (Farm A: χ 2 =264.7, P≤0.001; Farm B: χ 2 =511.1, P≤0.001). The percentage of main removal reasons decreased, whereas the frequency of culling due to age increased. Using survival analysis (Kaplan-Meier method and Cox proportional hazard model), significant differences were identified between the PLT of sows culled due to reproductive problems (P≤0.001), leg problems (P≤0.001) and old age (P≤0.001). Reproductive problems (HR: 1.34, P≤0.001) and leg problems (HR: 1.39, P≤0.001) were higher and culling due to old age (HR: 0.44, P≤0.001) was lower on Farm A compared to Farm B. There were no significant differences between the two farms in terms of mortality (HR: 0.99, P=0.923). Overall, the results can be useful for breeders of crossbred (dlw × DL) sow populations in more accurately defining their culling systems.
The European Commission (EC) has monitored Member States' digital progress through the Digital Economy and Society Index (DESI) since 2014. The DESI index currently ranks the EU Member States and monitors their progress based on four core and 33 individual indicators. We sought to determine whether convergence between the Member States could be detected using the DESI’s annual databases. By examining the variation in the indices, we propose the existence of a so-called “Matthew effect”, i.e., the “rich get richer” syndrome among the 27 EU Member States. We also hypothesised that the COVID-19 pandemic would influence the change in the DESI. Issues investigated were those using bibliometric, statistical-mathematical methods. The σ-convergence analysis was used to estimate the reduction over time of the differences between the Member States, while the β-convergence analysis was used to estimate the rate of catching up with the initial level of development. A PCA analysis was performed to verify the Mathew effect with additional λ-variances considering real GDP per capita change. The σ-convergence was confirmed over the period 2016–2021. The β-convergence was significantly confirmed, and the research also revealed that the half-life of catching up is approximately 20 years. The suggestion of a Matthew effect in the 2016–2021 period, although not significantly confirmed, tends to suggest its existence. The COVID-19 pandemic’s impact on the value of the DESI index is likely to be affected, but future studies are needed to find support for this hypothesis. The study concludes that convergence between the EU-27 Member States can be detected based on the DESI, but this does not imply convergence for all four core DESI indicators.
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