Economics of robots and automation in field crop production

Precision Agriculture - This study reviewed research published after 1990 on the economics of agricultural mechatronic automation and robotics, and identified research gaps. A systematic search was...     

Availability of Cu and Zn in an acidic sludge-amended soil as affected by zeolite application and liming

Purpose  

Acidic soils exhibit high trace element availability compared to neutral pH soils, and thus, when trace metals are added (e.g. due to sewage sludge application), measures should be taken to reduce their mobility. In this experiment, we tested two such methods, liming and zeolite addition. The aim was to measure the availability, in ryegrass (Lolium perenne L.), of heavy metals (Cu and Zn) added to soil with sewage sludge in both acidic and limed soil.     

Response of colour and hygroscopic properties of Scots pine wood to thermal treatment

The effect of heat treatment on the surface colour and hygroscopic properties of pine wood were investigated in this study. Boards of Scots pine wood (Pinus sylvestris L.) were subjected to thermal treatment at 200°C, for 4, 6, and 8 h. The change of equilibrium moisture content and density values of the specimens in order to facilitate the understanding of the treated material behavior. The colour parameters L*, a* and b*, used to depict the total colour change (Δ E) of wood surface, were shown to change proportionally to the treatment intensity. Moreover, swelling in the tangential and radial directions and absorption of the specimens appeared to be enhanced in great extent by the thermal treatment process. The mean value of swelling percentage in the tangential direction decreased 10.26%, 17.22%, and 19.60% for specimens treated for 4, 6, and 8 h, respectively, referring to the final measurement after 72 h of immersion. In radial direction, mean value of swelling percentage decreased 19.56%, 32.75%, and 34.65% for treated for 4, 6 and 8 h, respectively, after 72 h immersion, which attests the decrease in swelling and improvement in the hygroscopic behavior of Scots pine wood.     

The influence of respiratory disease on the energy envelope dynamics of pig cough sounds

The objective of this paper is to assess if the dynamics in the energy envelope of pig cough sounds are related to pathological conditions of the respiratory system. Two groups of pigs are compared. The first group, the sick pigs, is suffering from pneumonia by infection of Pasteurella Multocida. The second group, the control group, consists of healthy pigs which produced induced coughs by nebulisation of citric acid. The cough sounds of both groups were used to calculate the energy envelope, after which two signals are derived for further modelling. The first signal is an artificial step input, the second signal is part of the energy envelope of the cough signal that starts at the maximum level and decays in time. Using an autoregressive model estimation technique, the decay of the energy envelope is modelled as an input–output system. Based on the Young Identification Criterion (YIC) and R², the optimal model is proven to be a first order model with a first order denominator. Using this first order transfer function structure to model all cough sounds, the time constant of the simulated output is estimated based on the model parameters. The time constant shows significant higher values for the decay of the cough signals from pigs which are infected with Pasteurella Multocida compared to non-infected pigs (P < 0.0001). The results are in accordance with previous work in which pathological conditions have shown to influence cough sound duration. This modelling technique gives more insight in the effect of changes in lung condition on cough sound generation and might be incorporated in techniques for automatic cough evaluation.     

Histochemical study of the intestinal absorption,liver and lens effect with zinc‐supplemented diets for gilthead seabream

To describe the effect and the distribution of zinc in different tissues of a representative marine fish species, gilthead seabreams (Sparus aurata Linnaeus, 1758) were fed different diets containing zinc in different sources (organic, inorganic, encapsulated, blood‐rich diet or fishmeal). The effect was monitored by histology in the lens, liver and intestine. In addition, the anterior and posterior intestine was studied by means of autometallography, a histochemical silver‐based staining method to determine the zinc flow and distribution. The histology of lens did not improve by dietary zinc as there was no occurrence of cataracts. In the liver, the experimental diets were correlated with different changes in the tissue architecture. In the intestine, no histological changes were found using haematoxylin and eosin stain. However, with the use of autometallography stain, it was possible to visualize and describe the route that zinc follows through the enterocytes and the lamina propria. Organic and inorganic zinc diet produced the richest silver deposition in the anterior intestine.     

The effect of a natural feed additive (Macleaya cordata), containing sanguinarine,on the performance and health status of weaning pigs

The aim of this study was to investigate the efficacy of Sangrovit^®, a plant‐derived feed additive, given throughout the nursery stage via feed at 15 ppm and 50 ppm, on the health status and performance of weaners against negative controls. In a 900‐sow farrow‐to‐finish farm, a total of 864 piglets were divided into three groups: (i) negative controls (NC); (ii) Sang 15: same feed as NCs, plus 15 g Sangrovit^® /t of feed; (iii) Sang 50: same feed as NCs plus 50 g Sangrovit^® /t of feed. The results indicated that administration of 50 ppm^‐Sangrovit^® had the most beneficial effects on growth performance in weaning pigs. Specifically there was increase of body weight and average daily gain, as well as reduction of feed conversion ratio. Blood analysis from the Sang groups and especially the Sang 50 group revealed low values of haptoglobin and serum amyloid A.     

Boron behavior in apple plants in acidic and limed soil

In dry Mediterranean‐type climates boron (B) levels may naturally be high and even toxic to plants. Although liming of an acidic soil is expected to decrease B levels, it is not known what the effects would be in such areas of high‐B soils, especially in B‐sensitive crops such as apple trees. Thus, our aim was to study the behavior of added B in newly planted apple rootstocks in an acidic soil which was limed to pH 6.5 in an outdoor pot experiment. Added B increased significantly B extractability from soil, and B levels were lower in the limed compared to the acidic soils. Plant B concentrations also increased with added B but differences between limed and unlimed soils were not evident, because plant B did not seem to reflect changes in B behavior in soil. However, B uptake was significantly increased with added B, and was further increased with liming, contrary to what the soil extractions indicated, due to improved growth conditions. Our results show that although liming decreased soil B levels, at the same time it did not affect plant B concentration and accelerated the uptake of added B, indicating a possibility for increased soil‐to‐plant mobility of B.     

Studies on the infection and parasitism course of sclerotia of Sclerotinia sclerotiorum by three different mycoparasites

Journal of Plant Diseases and Protection - Mycoparasitism is an important process in microcosm of microorganisms. Understanding the mechanisms taking place may allow to effectively improved...     

Effects of fish meal replacement with full-fat soy meal on growth and tissue fatty acid composition in Atlantic cod (Gadus morhua)

Atlantic cod of initial mean weight approximately 220 g were fed a control diet and three diets in which fish meal (FM) was replaced with increasing levels of full-fat soybean meal (FFS) supplied at 12, 24, and 36% of dry diet, for 12 weeks. There were no significant differences in final weights, but the specific growth rate (SGR) was significantly higher in fish fed the control (FFS0) diet compared to fish fed the FFS12 and FFS36 diets, and the feed conversion ratio (FCR) was significantly lower in fish fed the FFS0 diet compared to the other three treatments. The fatty acid (FA) compositions of the cod muscle and liver were highly affected by dietary treatment, and linear relationships between dietary and tissue FA concentrations were shown for some of these. Moreover, selective utilization or accumulation in the tissues of specific FA was suggested by the results.     

Real-time analysis of chicken embryo sounds to monitor different incubation stages

The objective of this paper is to develop an algorithm that could be used in order to reduce the spread of chicken hatching in industrial incubators for chicken eggs. The approach that is used is based on frequency analysis of sounds recorded inside the industrial incubator and aims at identifying the time at which all the eggs inside the incubator have reached the internal pipping stage. The developed algorithm is able to be calibrated automatically in order to adjust for sounds around the incubator and the acoustics of every incubator. The algorithm has been implemented in a Digital Signal Processor and applied in real-time in an industrial environment. It is shown that the algorithm can correctly identify the time at which 93-98% of the eggs have had been in the internal pipping stage. This level of accuracy is considered adequate for a practical application focusing on reduction of the hatching window.