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See detailCaractérisation de la diversité des stratégies conçues par les producteurs laitiers wallons : déterminants socio-économiques et dynamique d’adaptations face aux enjeux passés, présents et futurs
Dalcq, Anne-Catherine ULiege

Doctoral thesis (2020)

Agricultural producers are necessary for reasons of food security but they are subject to great economic, social and environmental issues, jeopardizing their continuity. More particularly, the European ... [more ▼]

Agricultural producers are necessary for reasons of food security but they are subject to great economic, social and environmental issues, jeopardizing their continuity. More particularly, the European dairy producers have recently experienced a big change of their economic and political context following the end of the dairy quota system. For the sustainability of the sector and what this implies for our society and our environment, it is interesting to know the development paths implemented, planned and considered by the producers facing these changes. This thesis studied these development paths from the point of view of the producers, who are the first to be impacted by these changes of context and the first actors of solutions needed to adapt and maintain a profitable activity. The actions and the opinions of the Walloon producers were studied using the technicoeconomic database of Elevéo as well as surveys conducted in 2014-2015 and 2020. The objectives of the thesis were (1) to study the strategies of the producers and the evolution of these strategies in a recent past, their planning from 2020 onwards and their consideration for an ideal future, (2) to study the link between these strategies and other information, reflecting the causes of these choices, the environmental considerations, the wishes for training and the quality of life of the producers, providing an insight of the determining factors and the sustainability of these strategies, (3) to study the relevance to adapt the management depending on the adopted strategy(ies). First, the level of intensification was measured in this thesis thanks to an index created on the basis of several variables related to feeding, coming from the technicoeconomic database. This index aims to provide a more complete and exact measure tool of intensification. Its evolution between 2007 and 2017 was measured per individual to highlight the evolution patterns. We observed that 27% of producers were having a constant evolution, 8% a linear positive tendency, 24% a quadratic evolution with a maximum in 2012, which was a year of dairy crisis. Secondly, just before the end of the dairy quota system (2014-2015), 3 strategies of production in the short term in post quota era were studied and concerned: the increase of the milk quantity produced, the alternative valorization of milk production and the diversification of the activities. We found out that, according to the survey, more than half of the producers (55%) have chosen the status quo in quantity of milk produced, nearly 40% the increase of the production, 10% the alternative valorization and 10% the diversification of the activities. This shows that alternative activities were seldom considered by the producers on the eve of an important change of the production framework, in contrast to the increase of the dairy production activity. Thirdly, the characteristics of the ideal farm of the future were studied throughout 7 strategies : intensive vs. extensive, specialized vs. diversified, weakly vs. strongly based on new technologies, management by an independent producer vs. by an association of producers, familial vs. salarial workforce, production of milk with a standard vs. differentiated quality, for the global vs. local market. From the multivariate analysis of the answers of the producers collected in the 2014-2015 survey, clusters between some characteristics were observed, leading to highlight two models of ideal future farm : the “Local-based extensive”(LBE) model and the “Global-based intensive” (GBI) model supported, respectively, by 26% and 46% of producers respondents. The producers were positioning themselves more or less strongly regarding these two extremes. Hence, a gradient of ideal future farm (IFF) between the model LBE and GBI was defined to express the tendency of a producer to consider a model or the other as ideal. Significant relationships were then observed between the IFF gradient and the variables related to the reasons of the choice of this model, the environmental considerations and the training. Thus, the producers tending to GBI or LBE model do not have the same environmental considerations and represent two different guests in terms of training paths and areas. Fourth, the producers with different production systems were selected to answer a survey concerning their quality of life. No significant relationship was observed between the variables linked to quality of life and their production profile, except for the mixed producers (i.e., having several activities on the farm, i.e., 3rd group that standed out of the variability of the surveyed producers) who showed some lower quality of life results and for the extensive producers who were better supporting the society perception of the agriculture. Thus, the farm model does not seem to impact the quality of life of the producers, except if they have several activities. Fifth, we studied the relevance to vary a management parameter in particular, the calving interval (CI), as a function of the feeding systems. Significantly different gross margins per cow were observed between the herds having different percentages of cows with short or long CI, inside the different feeding systems. This chapter allowed to understand the effects of feeding on the herd and the importance to take them into account to define the herd management that maximizes the economic results. Finally, all these results allowed to establish a temporal evolution of the strategies of dairy producers, to provide an overview of the sustainability of the two models of farm supported for the future and to draw a scenario of the causes leading to this choice. The survey of 2020, conducted in Wallonia, allowed to bring additional information regarding the points raised in this thesis, 5 years after the end of the dairy quota system. The results of this survey validate or record the evolution of the tendencies observed previously and show a change of strategy concerning the ideal future farm. Indeed, the current occurrence is that 49% of the producers are in favour of LBE model vs. 33% of GBI model. In conclusion, the strategies of dairy producers are multiple and have evolved these last years, in relation to the available resources, the mentality of the producers and the changing framework, whose major event was the end of the dairy quota system. The occurrence of the producers between LBE and GBI is important to know given their economic, social and environmental sustainability. Thus, in order to build a suitable framework for the dairy activity for the next years and generations, this information must be taken into account by all the actors on the ground. [less ▲]

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See detailStrategies of the Walloon dairy producersfaced to the uncertain dairy future
Dalcq, Anne-Catherine ULiege; Dogot, Thomas ULiege; Soyeurt, Hélène ULiege et al

Conference (2020, January 31)

This study observes the strategies, and their determinants, of the Walloon dairy producersfaced to the post quota perspective through the realisation of 245 surveys, conducted from November 2014 to ... [more ▼]

This study observes the strategies, and their determinants, of the Walloon dairy producersfaced to the post quota perspective through the realisation of 245 surveys, conducted from November 2014 to February 2015. It highlights how dairy production companies plan to evolve to cope with this great change in the sector and so how will move the production of our dairy products. Three kinds of strategical variables were defined and related to the evolution of milk production (MP) [the producerswho increase MP (HighMP) vs. keep constant MP (ConstantMP) vs. stop MP]; the valorisation of MP [alternative (ValMP)vs. classical] and the diversification of activities [with (DivMP) vs. without such activities]. The relationships between the chosen strategies and the quantitative technical variables were studied using generalised linear models. The independence between qualitative technical variables and the strategical variables was tested using Chi Square test. HighMP and ConstantMP producersrepresent 38.4% and 53.9% of respondents, respectively. HighMP producerswere significantly more declared as legal entity (p-value = 0.03), had more family members on the farm (p-value<0.01), larger agricultural area in property (p-value = 0.03) and higher MP quota(p-value = 0.01)compared to ConstantMP producers. Only 9.8% of respondents decide to valorise differently MP. ValMP producerstend to have more employees (p-value = 0.08) and an agricultural area less fragmented (p-value = 0.07)than classical producers. A total of 7.8% of respondents decide to develop other activities. DivMP producerstend to have more employees (p-value = 0.10), more agricultural area in property (p-value = 0.03) and a more recent year of installation (p-value < 0.01). Finally, 44.9% of ConstantMP producersdo not want to start an alternative valorisation of MP and diversify their activities. In conclusion, a relationship exists between, amongst others, the legal status, workforce available, characteristics of the agricultural area, the dairy production and the strategy chosen by the Walloon dairy producers. [less ▲]

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See detailSuccessful economic management differs between intensive and extensive dairy farms
Dalcq, Anne-Catherine ULiege; Beckers, Yves ULiege; Wyzen, Benoit et al

Conference (2019, August 26)

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See detailBehavior patterns to the intensification vary differently within dairy producers
Dalcq, Anne-Catherine ULiege; Beckers, Yves ULiege; Wyzen, Benoit et al

Conference (2018, August 27)

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See detailRelationships between milk mid-IR predicted gastro-enteric methane production and the technical and financial performance of commercial dairy herds
Delhez, Pauline ULiege; Wyzen, Benoit; Dalcq, Anne-Catherine ULiege et al

in Animal (2018), 12(9), 1981-1989

Considering economic and environmental issues is important in ensuring the sustainability of dairy farms. The objective of this study was to investigate univariate relationships between lactating dairy ... [more ▼]

Considering economic and environmental issues is important in ensuring the sustainability of dairy farms. The objective of this study was to investigate univariate relationships between lactating dairy cow gastro-enteric methane (CH4) production predicted from milk mid-infrared spectra and technico-economic variables by the use of large scale and on-farm data. A total of 525,697 individual CH4 predictions from milk mid-infrared spectra [MIR-CH4 (g/day)] of milk samples collected on 206 farms during the Walloon milk recording scheme were used to create a MIR-CH4 prediction for each herd and year (HYMIR-CH4). These predictions were merged with dairy herd accounting data. This allowed a simultaneous study of HYMIR-CH4 and 42 technical and economic variables for 1,024 herd and year records from 2007 to 2014. Pearson correlation coefficients (r) were used to assess significant relationships (P < 0.05). Low HYMIR-CH4 was significantly associated with, amongst others, lower fat and protein corrected milk (FPCM) yield (r = 0.18), lower milk fat and protein content (r = 0.38 and 0.33, respectively), lower quantity of milk produced from forages (r = 0.12) and suboptimal reproduction and health performance (e.g. longer calving interval (r = -0.21) and higher culling rate (r = -0.15)). Concerning economic results, low HYMIR-CH4 was significantly associated with lower gross margin per cow (r = 0.19) and per litre FPCM (r = 0.09). To conclude, this study suggested that low lactating dairy cow gastro-enteric CH4 production tended to be associated with more extensive or suboptimal management practices, which could lead to lower profitability. The observed low correlations suggest complex interactions between variables due to the use of on-farm data with large variability in technical and management practices. [less ▲]

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See detailDecrease in the photosynthetic performance of temperate grassland species does not lead to a decline in the gross primary production of the ecosystem
Digrado, Anthony ULiege; Gourlez de la Motte, Louis ULiege; Bachy, Aurélie ULiege et al

in Frontiers in Plant Science (2018), 9

Plants, under stressful conditions, can proceed to photosynthetic adjustments in order to acclimatize and alleviate the detrimental impacts on the photosynthetic apparatus. However, it is currently ... [more ▼]

Plants, under stressful conditions, can proceed to photosynthetic adjustments in order to acclimatize and alleviate the detrimental impacts on the photosynthetic apparatus. However, it is currently unclear how adjustment of photosynthetic processes under environmental constraints by plants influences CO2 gas exchange at the ecosystem-scale. Over a two-year period, photosynthetic performance of a temperate grassland ecosystem was characterized by conducting frequent chlorophyll fluorescence (ChlF) measurements on three primary grassland species (Lolium perenne L., Taraxacum sp., and Trifolium repens L.). Ecosystem photosynthetic performance was estimated from measurements performed on the three dominant grassland species weighed based on their relative abundance. In addition, monitoring CO2 fluxes was performed by eddy covariance. The highest decrease in photosynthetic performance was detected in summer, when environmental constraints were combined. Dicot species (Taraxacum sp. and T. repens) presented the strongest capacity to up-regulate PSI and exhibited the highest electron transport efficiency under stressful environmental conditions compared with L. perenne. The decline in ecosystem photosynthetic performance did not lead to a reduction in gross primary productivity, likely because increased light energy was available under these conditions. The carbon amounts fixed at light saturation were not influenced by alterations in photosynthetic processes, suggesting photosynthesis was not impaired. Decreased photosynthetic performance was associated with high respiration flux, but both were influenced by temperature. Our study revealed variation in photosynthetic performance of a grassland ecosystem responded to environmental constraints, but alterations in photosynthetic processes appeared to exhibit a negligible influence on ecosystem CO2 fluxes. [less ▲]

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See detailThe feeding system impacts relationships between calving interval and economic results of dairy farms
Dalcq, Anne-Catherine ULiege; Beckers, Yves ULiege; Mayeres, Patrick et al

in Animal (2017)

The calving interval (CI) can potentially impact the economic results of dairy farms. This study highlighted the most profitable CI and innovated by describing this optimum as a function of the feeding ... [more ▼]

The calving interval (CI) can potentially impact the economic results of dairy farms. This study highlighted the most profitable CI and innovated by describing this optimum as a function of the feeding system of the farm. On-farm data were used to represent real farm conditions. A total of 1832 accounts of farms recorded from 2007 to 2014 provided economic, technical and feeding information per herd and per year. A multiple correspondence analysis created four feeding groups: extensive, low intensive, intensive and very intensive herds. The gross margin and some of its components were corrected to account for the effect of factors external to the farm, such as the market, biological status, etc. Then the corrected gross margin (cGMc) and its components were modelled by CI parameters in each feeding system by use of GLM. The relationship between cGMc and the proportion of cows with CI<380 days in each feeding group showed that keeping most of the cows in the herd with CI near to 1 year was not profitable for most farms (for the very intensive farms there was no effect of the proportion). Moreover, a low proportion of cows (0% to 20%) with a near-to-1-year CI was not profitable for the extensive and low intensive farms. Extending the proportion of cows with CI beyond 459 days until 635 days (i.e. data limitation) caused no significant economic loss for the extensive and low intensive farms, but was not profitable for the intensive and very intensive farms. Variations of the milk and feeding components explained mainly these significant differences of gross margin. A link between the feeding system and persistency, perceptible in the milk production and CI shown by the herd, could explain the different relationships observed between the extent of CI and the economic results in the feeding groups. This herd-level study tended to show different economic optima of CI as a function of the feeding system. A cow-level study would specify these tendencies to give CI objectives to dairy breeders as a function of their farm characteristics. [less ▲]

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See detailIdeal future dairy farm: a Walloon breeders’ point of view
Dalcq, Anne-Catherine ULiege; Soyeurt, Hélène ULiege; Dogot, Thomas ULiege et al

Conference (2017, August 30)

This research aims to characterize the dairy breeders regarding their idea of the ideal future farm ensuring them an income, in order to highlight their present situation and the ways to advise them ... [more ▼]

This research aims to characterize the dairy breeders regarding their idea of the ideal future farm ensuring them an income, in order to highlight their present situation and the ways to advise them towards their wished dairy model. The 245 answers to a survey of breeders, conducted between November 2014 and February 2015 provided information about, amongst others, their wishes concerning the intensification, the specialization, the technological innovation, the kind of workforce, structure, market and milk production (standard vs. differentiated quality milk). Based on this information, a Multiple Correspondence Analysis allowed to create 4 groups of breeders with a similar view of their ideal farm: global-based intensive (GBIb), local-based extensive (LBEb), intermediate and no-opinion breeders. The relationships between these groups and the other recorded qualitative variables as formation needed, obstacles and advantages of breeders organization, of diversification and so forth w ere studied using Chi Square tests and Correspondence Canonical Analysis. A moderate link was observed between the ideal future farm and the current situation of the respondent. This suggested that not all the breeders were in the production system that they considered as most profitable. As a brake to the transformation and diversification, GBIb tended to be more numerous to speak about the uncertainty of the customer loyalty (p-value = 0.07) and LBEb pointed out the size of the investments (p-value = 0.05). LBEb asked more for administrative (p-value = 0.04) and transformation and diversification formations (p-value = 0.03) while GBIb looked more for finance and management formation (p-value = 0.02). In conclusion, there were different ideal dairy farm models considered by the breeders. Their needs were not similar and indicated which tools must be developed and which domain must be studied to support them. [less ▲]

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See detailRelationships between methane emissions and technico-economic data from commercial dairy herds
Delhez, Pauline ULiege; Wyzen, B.; Dalcq, Anne-Catherine ULiege et al

Conference (2017, August)

Considering economic and environmental issues is important for the sustainability of dairy farms. Regarding environment, direct methane (CH4) emissions from cows are of increasing concern. Many studies ... [more ▼]

Considering economic and environmental issues is important for the sustainability of dairy farms. Regarding environment, direct methane (CH4) emissions from cows are of increasing concern. Many studies examined CH4 variation factors but often on a low number of experimental cows. Also, few studies linked CH4 to economic aspects of dairy farms. The innovative aim of this study was to highlight technical factors associated with dairy cow CH4 emissions and gain insight into the relationships between CH4 and herd economic results by the use of large scale and on-farm data. A total of 525,697 individual CH4 predictions from milk mid-infrared (MIR) spectra [MIR-CH4 (g/day)] of milk samples collected on 206 farms during the Walloon milk recording were used to create a CH4 proxy at the herd by year (herd*year) level. This proxy was merged with accounting data. This allowed a simultaneous study of CH4 emissions and 56 technico-economic variables for 1,024 herd*year records from 2007 to 2014. Significant effects were detected from ANOVA analyses and correlations (r). MIR-CH4 was weakly linked to technical variables considered individually (r < 0.38), suggesting complex associations between variables. Lower MIR-CH4 was associated with lower fat and protein corrected milk (FPCM) yield (r=0.18), lower milk fat and protein content (r=0.38 and 0.33, respectively), lower quantity of milk produced from forages (r=0.12) and suboptimal reproduction and health performances (e.g. higher calving interval (r=-0.21), higher culling rate (r=-0.15)). On an economic point of view, lower MIR-CH4 was associated with lower gross margin per cow (r=0.19) and per litre FPCM (r=0.09). To conclude, this study suggested that low dairy cow CH4 emissions tended to be associated with suboptimal and also less profitable herd management practices. Further research is needed to confirm and expand on these results. [less ▲]

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See detailCharacterisation of Luvisol compaction under two different tillage systems and field traffic zones by assessing soil mechanical properties
Taguem Ngoualadjio, Eric Martial ULiege; Destain, Marie-France ULiege; ROISIN, Christian et al

Conference (2017, June 20)

Compaction of arable soils is a consequence of tillage systems and agricultural machinery traffic year after year. Its negative effects on crop production and on the environment have been put into ... [more ▼]

Compaction of arable soils is a consequence of tillage systems and agricultural machinery traffic year after year. Its negative effects on crop production and on the environment have been put into evidence by several studies. However, soil compaction is a complex phenomenon and the understanding of the involved mechanisms related to agricultural practices still remains limited. This contribution aims to study the influence of the interaction between traffic intensity and tillage system on soil compaction. Soil samples were taken from topsoil (0.07-0.25 m), plough pan (0.30-0.35 m) and subsoil (0.35 – 0.52 m), on plots under long-term reduced tillage (RT) and conventional tillage (CT). For each tillage system, intensive traffic zones (IT) and non-intensive traffic zones (NT) were considered. Swelling index (Cs), compression index (Cc), precompression stress (Pc) obtained by oedometer test, porosity (n) and water content obtained by gravimetric determination were chosen to characterise the soil mechanical properties. An analysis of covariance (ANCOVA) was performed to study the effect of the depth, the tillage and the traffic intensity on the variables measured, with the water content as covariable. The results show that, after ten years of reconversion from CT to RT, the plough pan is still present in RT and its compaction appears as important as in CT ( nRT-30cm = 36.9% , nCT-30cm = 38.0%, p-value = 0.098). In subsoil, the compression index was high in CT, as well as in RT (CcRT = 0.150 kPa-1, CcCT = 0.148 kPa-1, p-value = 0.617), involving that this layer remains susceptible to compaction under heavy loads. Moreover, the mean value of the precompression stress (meanPc = 92±34 kPa) remains lower than stresses induced by heavy machines such as beet harvesters. The results also show that the presence of two traffic zones induces a spatial heterogeneity in the field (CcIT = 0.138 kPa-1; CcNT = 0.154 kPa-1, p-value = 0.031). These main results could be used in computational modelling to develop decision support systems to mitigate the effects of soil compaction. [less ▲]

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See detailWater Vapor Permeability of Edible Films Based on Improved Cassava (Manihot esculenta Crantz) Native Starches
Adjouman, Yao Désiré; Nindjin, Charlemagne; Tetchi, F.Achille et al

in Journal of Food Processing and Technology (2017), 8

Starch is used in the production of edible biodegradable packaging as an attractive alternative to synthetic polymers because it is a natural biopolymer of low cost and high availability. Many studies ... [more ▼]

Starch is used in the production of edible biodegradable packaging as an attractive alternative to synthetic polymers because it is a natural biopolymer of low cost and high availability. Many studies have been carried out on films based on cassava starch and the results show that these have good flexibility and low water vapor permeability. This present research was conducted to analyse the effect of glycerol, peanut oil and soybean lecithin on the water vapor permeability (WVP) of edible films based on improved cassava (Manihot esculenta Crantz) native starches from Côte d’Ivoire. The films were prepared using 4 g cassava starch, 25% and 30% glycerol (w/w), 5% and 10% peanut oil (w/w) and 0% to 5% soybean lecithin (w/w oil) in Petri dishes. The WVP of the films was determined at 25°C and 75% relative humidity. The moisture content of the films was determined in an oven at 105°C and the film thickness was determined manually using a micrometer. The resulting films were homogeneous, transparent and crack-free. WVP, moisture content and thickness of the films increased with increasing glycerol concentration. Increasing the concentrations of the peanut oil and soybean lecithin decreased the thickness and increased the moisture content of the films. The combination of glycerol and peanut oil increased the WVP of the films, whereas addition of soybean lecithin had no effect. The lowest WVP values were obtained using 25% glycerol, 5% peanut oil and 5% soybean lecithin. Starch obtained from improved cassava varieties cultivated in Côte d’Ivoire can be a potential ingredient in the production of food packaging. [less ▲]

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See detailRelationships between methane emissions from dairy cows and farm technico-economic results
Delhez, Pauline ULiege; Wyzen, Benoit; Dalcq, Anne-Catherine ULiege et al

Poster (2017, February 07)

Considering economic and environmental issues is important for the sustainability of dairy farms. Regarding environment, direct methane (CH4) emissions from cows are of increasing concern. Many studies ... [more ▼]

Considering economic and environmental issues is important for the sustainability of dairy farms. Regarding environment, direct methane (CH4) emissions from cows are of increasing concern. Many studies examined CH4 variation factors but often on a low number of experimental cows. Also, few studies linked CH4 to economic aspects of dairy farms. The innovative aim of this study was to highlight technical factors associated with dairy cow CH4 emissions and gain insight into the relationships between CH4 and herd economic results by the use of large scale and on-farm data. A total of 525,697 individual CH4 predictions from milk mid-infrared (MIR) spectra [MIR-CH4 (g/day)] of milk samples collected on 206 farms during the Walloon milk recording were used to create a CH4 proxy at the herd by year (herd*year) level. This proxy was merged with accounting data. This allowed a simultaneous study of CH4 emissions and 56 technico-economic variables for 1,024 herd*year records from 2007 to 2014. Significant effects were detected from ANOVA analyses and correlations (r). MIR-CH4 was weakly linked to technical variables considered individually (r < 0.38), suggesting complex associations between variables. Lower MIR-CH4 was associated with lower fat and protein corrected milk (FPCM) yield (r=0.18), lower milk fat and protein content (r=0.38 and 0.33, respectively), lower quantity of milk produced from forages (r=0.12) and suboptimal reproduction and health performances (e.g. higher calving interval (r=-0.21), higher culling rate (r=-0.15)). On an economic point of view, lower MIR-CH4 was associated with lower gross margin per cow (r=0.19) and per litre FPCM (r=0.09). To conclude, this study suggested that low dairy cow CH4 emissions tended to be associated with suboptimal and also less profitable herd management practices. Further research is needed to confirm and expand on these results. [less ▲]

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See detailLong-term measurements of chlorophyll a fluorescence using the JIP-test show that combined abiotic stresses influence the photosynthetic performance of the perennial ryegrass (Lolium perenne) in a managed temperate grassland
Digrado, Anthony ULiege; Bachy, Aurélie ULiege; Mozaffar, Ahsan et al

in Physiologia Plantarum (2017), 161(3), 355-371

Several experiments have highlighted the complexity of stress interactions involved in plant response. The impact in field conditions of combined environmental constraints on the mechanisms involved in ... [more ▼]

Several experiments have highlighted the complexity of stress interactions involved in plant response. The impact in field conditions of combined environmental constraints on the mechanisms involved in plant photosynthetic response, however, remains understudied. In a long-term field study performed in a managed grassland, we investigated the photosynthetic apparatus response of the perennial ryegrass (Lolium perenne L.) to environmental constraints and its ability to recover and acclimatize. Frequent field measurements of chlorophyll a fluorescence (ChlF) were made in order to determine the photosynthetic performance response of a population of L. perenne. Strong midday declines in the maximum quantum yield of primary photochemistry (FVFM) were observed in summer, when a combination of heat and high light intensity increased photosynthetic inhibition. During this period, increase in photosystem I (PSI) activity efficiency was also recorded, suggesting an increase in the photochemical pathway for de-excitation in summer. Strong climatic events (e.g. heat waves) were shown to reduce electron transport between photosystem II (PSII) and PSI. This reduction might have preserved the PSI from photo-oxidation. Periods of low soil moisture and high levels of sun irradiance increased PSII sensitivity to heat stress, suggesting increased susceptibility to combined environmental constraints. Despite the multiple inhibitions of photosynthetic functionality in summer, the L. perenne population showed increased PSII tolerance to environmental stresses in August. This might have been a response to earlier environmental constraints. It could also be linked to the selection and/or emergence of well-adapted individuals. © 2017 Scandinavian Plant Physiology Society [less ▲]

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See detailGamification croissante d’un quiz de chimie – Effets comparés sur la performance, la perception de compétence et l’état de flow
le Maire, Nathalie ULiege; Dalcq, Anne-Catherine ULiege; Colaux, Catherine ULiege et al

in Revue Internationale des Technologies en Pédagogie Universitaire (2017), 14(1), 69-83

Mini-games have recently emerged in the literature on gamification as an affordable alternative to immersive serious games. The present study aims to evaluate the effects of the use of chemistry minigames ... [more ▼]

Mini-games have recently emerged in the literature on gamification as an affordable alternative to immersive serious games. The present study aims to evaluate the effects of the use of chemistry minigames having a growing gamification on the performance, the self-confidence and the flow perceived by first year bioengineering students. Results indicate no effect on the first two parameters but show a positive effect on four dimensions of the flow. Given these mixed results, the conditions of an effective use of mini-games with undergraduate students are then discussed. [less ▲]

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See detailStrategies of the Walloon dairy breeders faced to the uncertain dairy future
Dalcq, Anne-Catherine ULiege; Dogot, Thomas ULiege; Soyeurt, Hélène ULiege et al

Conference (2016, September 01)

This study observes the strategies, and their determinants, of the Walloon dairy breeders faced to the post quota perspective through the realization of 245 surveys, conducted from November 2014 to ... [more ▼]

This study observes the strategies, and their determinants, of the Walloon dairy breeders faced to the post quota perspective through the realization of 245 surveys, conducted from November 2014 to February 2015. Three kinds of strategical variables were defined and related to the evolution of milk production (MP) [the breeders who increase MP (HighMP) vs. keep constant MP (ConstantMP) vs. stop MP]; the valorisation of MP [alternative (ValMP) vs. classical] and the diversification of activities [with (DivMP) vs. without such activities]. The relationships between the chosen strategies and the quantitative technical variables were studied using generalized linear models. The independence between qualitative technical variables and the strategical variables was tested using Chi Square test. HighMP and ConstantMP bredeers represent 38.4% and 53.9% of respondents, respectively. HighMP breeders were significantly more declared as legal entity (p-value = 0.03), had more family members on the farm (p-value<0.01), larger agricultural area in property (p-value = 0.03) and higher MP quota (p-value = 0.01) compared to ConstantMP breeders. Only 9.8% of respondents decide to valorise differently MP. ValMP breeders tend to have more employees (p-value = 0.08) and an agricultural area less fragmented (p-value = 0.07) than classical breeders. A total of 7.8% of respondents decide to develop other activities. DivMP breeders tend to have more employees (p-value = 0.10), more agricultural area in property (p-value = 0.03) and a more recent year of installation (p-value < 0.01). Finally, 44.9% of ConstantMP breeders do not want to start an alternative valorisation of MP and diversify their activities. In conclusion, a relationship exists between, amongst others, the legal status, workforce available, characteristics of the agricultural area, the dairy production and the strategy chosen by the Walloon dairy breeders. [less ▲]

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See detailContribution à l'optimisation technico-économique des élevages laitiers en Wallonie : l'intervalle vêlage
Dalcq, Anne-Catherine ULiege; Beckers, Yves ULiege; Dogot, Thomas ULiege et al

Conference given outside the academic context (2016)

Au cours des dernières décennies, l’intervalle vêlage des vaches laitières a eu tendance à s’allonger au niveau mondial, européen et belge. Les causes sont multiples : évolution du système de production ... [more ▼]

Au cours des dernières décennies, l’intervalle vêlage des vaches laitières a eu tendance à s’allonger au niveau mondial, européen et belge. Les causes sont multiples : évolution du système de production laitière, augmentation du niveau de production,… Les conséquences sont nombreuses également mais se traduisent-elles par un impact économique pour l’éleveur laitier ? La recherche présentée aujourd’hui se base sur près de 1800 bilans comptables de 400 exploitations laitières, fournis par le service technico-économique de l’Association Wallonne de l’Elevage, entre 2007 et 2014, pour déterminer l’impact économique de la durée de l’intervalle vêlage et définir l’optimum technico-économique de ce paramètre de management. Faut-il garder en tête « le veau par vache et par an » ou est-il intéressant économiquement d’allonger la période entre deux vêlages pour une même vache ? L’étude révèle qu’il y a bien une relation entre l’intervalle vêlage et les résultats économiques d’une exploitation. De plus, il n’y aurait pas un seul optimum d’intervalle vêlage mais plusieurs, dépendant du type d’exploitation et plus particulièrement du mode d’alimentation. L’optimum de l’intervalle vêlage a tendance à être plus court pour les exploitations à alimentation plutôt intensive et plus long pour les exploitations à alimentation plutôt extensive. Cependant il ne s’agit que de tendances observées, un travail plus approfondi doit encore être réalisé pour confirmer ces tendances et définir des objectifs plus précis à poursuivre pour maximiser la rentabilité de son exploitation. [less ▲]

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