Spanish Journal of Agricultural Research
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The Westernmost Mediterranean islands present an endemic varroosis disease pattern
No full textAim of study: This is the first intensive study of the incidence of Varroa destructor (Acari: Varroidae) in the Westernmost Mediterranean islands (Balearics).Area of study: Mallorca, Menorca, Eivissa and Formentera (Balearic Islands), Spain.Material and methods: The study was carried out in autumn 2010 and in spring 2011 because the presence of the mite is higher in these seasons. A total of 462 honeybee colonies were analyzed from different apiaries on. One sample of adult bees (worker bees, n > 200) and another of bee brood (at all stages of development, n> 400) were collected from each colony. All were frozen until analysis. To detect Varroa each sample was examined individually basing the study on the guide edited by the World Organisation for Animal Health, with some modifications. The beekeepers involved were interviewed to characterize Balearic beekeeping.Main results: Regarding the prevalence, results showed that in the Balearic Islands the percentage was higher in spring (34.78%) than in autumn (44.09%) but the infestation rate was lower in both seasons (Autumn: 0.94%, Spring: 0.77%). The focality percentage was also higher in spring (87.10%) than in autumn (82.61%). The data suggests that Varroa mites in the archipelago have an endemic rather than epidemic disease distribution pattern.Research highlights: These results open an interesting scenario to develop a future resistance breeding strategy against V. destructor in these small islands
Vaccination programs, parity, and calving season as factors affecting the risk of fetal losses and mummified fetuses in Holstein cows
No full textAim of the study: To investigate vaccination programs, parity, and calving season as factors affecting the risk of abortion and mummified fetuses in Holstein cows.Area of study: Hot zone of Northeast Mexico.Material and methods: Multiple logistic regression models were used to examine the relationship between peripartum disorders, parity, previous occurrence of abortion, season of calving, vaccination program, incidence of abortion, and mummified fetuses in Holstein cows.Main results: For 7014 pregnancies (2886 cows), the percentage of cows aborting and having mummified fetuses was 17.7% and 1.1%, respectively. As the number of brucellosis vaccinations increased, the incidence of abortion increased (10.4% for a single vaccination and 38.0% for 6 accumulated vaccinations). Abortion for cows having 1-2 previous abortions (56%) and >2 abortions (77%) was fivefold and sevenfold greater (p<0.01), respectively, than that for cows without previous abortion. Other important risk factors for abortion were number of calvings (19.8% for nulliparous and primiparous vs. 13.8% for >3 parturitions; OR=1.7, p<0.01), leptospirosis vaccine application <55 days postpartum (dpp; OR=1.3, p<0.05), viral vaccine application >37 dpp (OR=1.3, p<0.01), brucellosis vaccine application >20 dpp (OR=1.6, p<0.01), and no application of clostridial vaccine (OR=3.7, p<0.01). Significant risk factors for mummified fetuses were application of ≥3 brucellosis vaccinations (OR=3.3, p<0.01), no application of 10-way clostridial vaccine (OR=2.3, p<0.01), >2 previous abortions (OR=18.4, p<0.01), and calving in autumn (OR=0.4, compared to winter, p<0.05).Research highlights: Risk of abortion and mummified fetuses in Holstein cows has been found to be related to vaccination programs
Factors affecting energy consumption and productivity in greenhouses
No full textAim of study: To investigate the impact factors affecting the greenhouse environment on energy consumption and productivity.Area of study: Alborz province of Iran during the period 2018–2020.Material and methods: In this study, 18 active units of greenhouse owners in Alborz province of Iran that had necessary standards were identified. Then, upper and lower amplitudes of the variables affecting productivity and energy consumption in greenhouses were calculated using a type-2 fuzzy neural network, Matlab 2017 software. Area, temperature, energy exchange, environmental evapotranspiration and relative humidity were studied as indicators.Main results: With each unit of temperature, energy consumption and productivity increased by 0.737% and 0.741%, respectively; with each unit of energy exchange, they increased by 0.813% and 0.696%, respectively; with each unit of evaporation and transpiration of the environment, they increased by 0.593% and 0.869%, respectively; and with each unit of humidity, they increased by 0.398% and 0.509%, respectively.Research highlights: The factors affecting the greenhouse environment such as area, temperature, evapotranspiration and relative humidity had a significant effect on productivity in studying greenhouses and therefore increasing their productivity. According to the results, the model’s ability in energy consumption was better than that for energy efficiency prediction. Also, greenhouse ranking was done by FAHP method
Relationship between efficiency and profitability: The case of Czech swine sector
No full textAim of study: To examine the link between economic efficiency and profitability of firms belonging to the swine sector.Area of study: This study is devoted to the Czech swine sector that forms the traditional and essential part of agriculture in the Czech Republic.Material and methods: Data from the Albertina CZ Gold Edition database for the period 2008-2017 were used. To evaluate the economic efficiency, the data envelopment analysis models are applied. Return on equity, return on assets and return on sales are used to measure profitability. To assess the relationship between economic efficiency and profitability, the Pearson correlation coefficient is used.Main results: The results demonstrate that there is no clear link between the economic efficiency of firms and their profitability in this industry. The correlation between all three profitability ratios and efficiency score were predominantly positive but not statistically significant in many cases. The economies of scale and scope and the construction of profitability indicators could be the main factors explaining the fact that companies achieving higher efficiency are not also more profitable.Research highlights: The study provides material useful to owners, managers, and customers of Czech agriculture firms. It identifies the relatively high efficiency of firms measured relatively to the best Czech company. In the European context, however, the efficiency of Czech firms belonging to the swine sector is low. It also reveals that the profitability of the firms is not a representative proxy for economic efficiency
Modelling the impacts of climate change on potential cultivation area and water deficit in five Mediterranean crops
No full textAim of study: To assess the impacts of climate change on local agriculture with a high resolution in a Mediterranean region with a diversity of climates.Area of study: Catalonia (NE Spain).Material and methods: Based on historical meteorological records and a regionalization of the RCP4.5 model created by the Catalan Meteorological Service, the Papadakis agro-climate classification was calculated for two climate scenarios. The changes in agro-climatic suitability and irrigation needs of five typical Mediterranean crops (alfalfa, almond, barley, olive and orange) were analysed. Main results: In the 2031-2050 climate scenario, over 15% of the study area will no longer be adequate for non-irrigated almond or olive, at locations in which they have been traditionally rainfed crops. If irrigation is provided, orange is likely to become agro-climatically suited for the entire Catalan coastline. Were the current crop distribution maintained, irrigation needs may increase on average 16% in the study area in the future scenario.Research highlights: High-resolution GIS data may be combined with Papadakis’ classical method to compare different climate scenarios and detect risks and opportunities for local and regional agriculture
Behavior of Spanish durum wheat genotypes against Zymoseptoria tritici: resistance and susceptibility
No full textAim of study: Septoria tritici blotch (STB), caused by the fungus Zymoseptoria tritici, is one of the most important wheat diseases worldwide, affecting both bread and durum wheat. The lack of knowledge about the interaction of durum wheat with Z. tritici, together with limited resources of resistant durum wheat material, have both led to a rising threat for durum wheat cultivation, particularly in the Mediterranean Basin. In Spain, STB has increased its incidence in the last few years, leading to higher costs of fungicide applications to control the disease. Therefore, identification of new sources of resistance through wheat breeding stands out as an efficient method of facing STB.Area of study: The experimental study was conducted in growth chambers at the IFAPA facilities in Córdoba (Spain).Material and methods: The percentage of necrotic leaf area, the disease severity, and the pycnidium development through image analysis were evaluated from 48 durum wheat Spanish accessions (breeding lines and commercial cultivars) in growth chambers against an isolate of Z. tritici from Córdoba.Main results: Two breeding lines and six commercial cultivars showed resistant responses by limiting STB development through the leaf or its reproduction ability, while the other 40 accessions presented a susceptible response.Research highlights: Provided these resources of resistance in Spanish durum wheat genotypes, future breeding programs could be developed, incorporating both agronomic traits and resistance to STB
Covid-19 lockdown and wine consumption frequency in Portugal and Spain
No full textAim of study: This study aims to analyse how psychological factors related to the Covid-19 lockdown affected the frequency of wine consumption among Iberian consumers.Area of study: To achieve this goal, we used data collected from an online survey in Europe comprising 4489 observations from Portuguese and Spanish samples.Material and methods: Using an ordered probit model, we analysed the wine consumption frequency as a function of a set of explanatory variables related to psychological factors, sociodemographic variables, consumption characterisation and channels of trade variables.Main results: The identification of the hedonic nature of wine consumption explains the increase in frequency, while the negative feelings associated with the lockdown and health concerns are not relevant, which implies a different effect on consumption than in the case of other disasters. Consumer loyalty before the lockdown and the role that technology has played in explaining the frequency of consumption in the form of apps, online purchasing and digital drinks opens up a new horizon in the study of consumer behaviour.Research highlights: Although econometrically different, the impact of the Covid-19 crisis tend to be felt similarly among the Iberian countries. The effects of psychological impacts related to feelings of Covid-19 of the lockdown does not show impact in wine consumption behaviour. The consumer background and behavioural attitude towards wine explain most changes in consumption pattern
Estimate of body growth curve and feed intake of free-range chickens receiving different levels of digestible lysine
No full textAim of the study: To adjust nonlinear Gompertz model to describe the body growth and feed intake (FI) of free-range chickens of the CPK (Color Plumé) strain, receiving different levels of digestible lysine (dig-Lys), from 21 to 77 days of age.Area of study: São Cristovão, Sergipe, Brazil.Material and methods: A total of 432 one-day-old unsexed chickens were used in the study. At 21 days of age, the birds were assigned to four treatments (0.85%; 0.97%; 1.09%; 1.21%) of dig-Lys, in a completely randomized design with four replicates, with 27 birds per experimental unit. The Gompertz model was used to estimate bird growth curves related to body weight (BW) and FI at each Lys level.Main results: The tests of comparison between the parameters of the Gompertz model for each Lys level showed that parameter A varied, while parameters B (0.0329) and C (45.819) did not differ significantly. In parameter A, the dig-Lys level of 0.97% provided the highest BW estimate at maturity and maximum BW at the inflection point.Research highlights: Use of non-linear models to predict nutritional requirements, helps farmers to optimize management decisions and, thus, maximize their profit. According to Gompertz model, it was possible to infer that the inclusion of 0.97% dig-Lys in the diet of mixed batches of free-range chickens of the CPK strain meets their nutritional requirements
Development of a vibrationless sorting system
No full textAim of study: Size classification is essential in many industrial processes. Most classical sorting systems use vibrations as a means of classification function. In this study, a vibration-free sorting system called helical cylindrical screen has been developed against the disadvantages of vibrating systems and proposed to be used in the sorting of crop seeds.Area of study: Adana City, Turkey.Material and methods: The movement of the seed mass on the screen surface was formulated and the mass movement along the circular-helical paths was analytically expressed, leading to some operational parameters for evaluation in the screen design. By combining the mass movement parameters with effective separation conditions, an algorithm was obtained against the desired mass flow rate to determine the appropriate values of the design parameters. Experiments were performed on the machine, which was manufactured to sort peanut seeds into two different sizes, small and large.Main results: The results obtained in the experiments (separation efficiency, mass flow rate, effect of grain size on separation efficiency and equilibrium angle) were compared with the theoretical ones. The separation efficiency of the machine (99% and above) was quite good and is not affected at all by the small size ratio contained in the mixtures. The limitations of the theoretical velocities (axis and tangent) of a seed moving on the cylindrical sieve were found to be consistent with those obtained experimentally.Research highlights: The helical cylindrical sieve can be used for other particulate agricultural products with smooth surfaces such as soybeans, kidney beans, peas, etc