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Our study aimed to evaluate the effects of nano and chelated Fe fertilization on nutrient and heavy metals uptake and their translocation from soil to root, stem, leaf, and fruits of fresh market tomatoes (Solanum Lycopersicon, cv. Sunbrite). A completely randomized design in a factorial experiment, with two Fe sources (nano vs. chelated) applied at 0 (control), 10, 20, and 40 mg/L via drip-irrigated plasticulture, was conducted. Nutrient and heavy metals concentrations in soil, water, tomato roots, stems, leaves, and fruits were determined. Soil had higher K, Fe, Ca, Mg, P, and Mn but lower Ni, Cd, and Cr concentrations. The P, K, Fe, Cu, Mn, and Na concentrations in the roots were significantly affected by both nano and chelated Fe fertilization; however, without following a consistent pattern. Averaged across the Fe treatments, K, Ca, Mg, Fe, and P that translocated from the soil were dominated in the roots, stems, and leaves. The nutrient translocation order, from roots to fruits in response to Fe fertilization, was nano Fe (40%) > chelated Fe (37%) > control (23%). Based on the treatment index values calculated across treatments, it is evident that Fe fertilization plays a pivotal role in nutrient uptake and translocation. The use of chelated Fe at a concentration of 20 mg/L had a pronounced effect on improving the nutritional quality of the tomatoes and, by extension, their associated public health benefits. In conclusion, the chelated Fe (20 mg/L) stands out as the most preferable and effective Fe fertilization for tomatoes. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to examine the effect that the order of administrating forages into the portion has on the consumption speed of the forages. Experiments A (order corn silage-pasture hay) and B (order pasture hay-corn silage) involved 10 multiparous Romanian Black and White cows. Cows were in their first 100 days of lactation and were housed in a tied stanchion barn 24 hours per day. Ration offered comprised corn silage (20 kg), pasture hay (8 kg), concentrates (3 kg) and brewer’s yeast (2 kg). Cows were fed three times per day, at 7:00, 13:00 and 19:00. Consumption speed was calculated in minutes per kilograms of raw feed. Average consumption speed values were calculated as follows: concentrates 3.04 min/kg, pasture hay 25.45 min/kg, corn silage 4.96 min/kg and brewer’s yeast 2.34 min/kg.

Distance is a key constraint for animals in moving between suitable habitats, but is this also the case in staging long-distance migrating shorebirds that habitually cover thousands of kilometers during migrations? We conducted multi-year field observations, benthic prey sampling and satellite tracking, to compare how endangered great knots Calidris tenuirostris respond to the food shortage at two similarly functioning staging sites (Gaizhou and Beijingzi) in the northern Yellow Sea, China. Food availability declined by >95 % at both sites across the study period, with the intake rates of great knots declining by 87 %. However, whereas the number of great knots declined by 91 % at Gaizhou, only a 29 % decrease was seen at Beiijngzi. Satellite tracking showed that during the time when food was poor in Gaizhou, tagged great knots crossed 20 km to suitable alternative high-quality sites where food was not scarce. From Beijingzi, tagged great knots flew at least 124 km to find a good alternative. We show that longer distances to alternative sites decreased the probability of a bird leaving. Thus, habitat degradation in staging sites induced great knots to move to alternative sites, but only if such alternatives were relatively close. As staging habitats become more isolated, the negative effects of habitat degradation will be more serious due to a distance constraint on exploratory movements. This emphasizes the importance of maintaining networks of nearby high-quality refueling sites for migratory birds to provide buffers in seasons when local food conditions are lean. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the feeding behaviour of indigenous goats and the selection drivers of different plant species in a Mediterranean forest rangeland. To achieve this goal, the seasonal variations in terms of forage availability and quality of ingested plant species were studied during three grazing seasons. In the same period, eight indigenous goats of Beni Arouss breed were selected to explore the seasonal changes in their browsing behaviour. Forage quality was determined by the hand-plucking technique. The results showed a wide seasonal variation in forage availability and quality, and feeding behaviour. Woody species were more selected independently of the season (p < 0.001). The crude protein content varied from 53.3 g/kg of dry mater (DM) for Erica arborea in summer to 197 g/kg DM for Calicotome villosa in autumn (p < 0.001). Despite the high condensed tannins content in selected shrubs, they were highly consumed. In vitro organic matter digestibility (IVOMD) and metabolizable energy (ME) had recorded the highest contents in herbaceous during spring. Shrubs and trees contain the lowest levels of IVOMD (<500 g/kg) and ME (<7.2 MJ/kg) during autumn and summer. It is concluded that seasonal changes in forage availability and quality did not necessarily affect the indigenous goats' preference. These findings could help goat herders to develop feeding and grazing systems while increasing the performance of goats in the Mediterranean silvopastoral system. [ABSTRACT FROM AUTHOR]

The costs and benefits of group living are not evenly distributed among individuals that occupy different spatial positions within a group (central or peripheral). However, the definitions of central and peripheral positions may artificially mask the true dynamics of cost and benefit of individuals. Using wintering foraging Greater White-fronted Geese (Anser albifrons) flocks as our study system, we measured individual spatial position within a flock as distance to the flock edge. First, we tested the effects of distance to edge on the antipredation cost and foraging benefit of individual goose using generalized linear mixed models (GLMMs). Flock size and number of neighbors and their interactions with distance to edge were included as fixed effects in GLMMs. Then we used piecewise regression to determine the threshold value of distance to edge to classify central and peripheral individuals. Our results indicated distance to edge significantly affected percent of time spent on vigilance (vigilance time), percent of time spent on foraging (foraging time) and intake rate (pecks/min), whereas other factors had no effects. We found that the critical distance that predicted changes in behavior was around 2.5 ​m. Birds 2.5 ​m or less from the edge of the group were more vigilant, and had less efficient foraging than more central individuals. Behavioral differences between central and peripheral individuals were more easily detected when the birds were classified by the method introduced in this study than by the traditional minimum convex polygon method. Our research provides researchers a dichotomous classification scheme that places individuals into peripheral and central positions from an individual's perspective.

The costs and benefits of group living are not evenly distributed among individuals that occupy different spatial positions within a group (central or peripheral). However, the definitions of central and peripheral positions may artificially mask the true dynamics of cost and benefit of individuals. Using wintering foraging Greater White-fronted Geese (Anser albifrons) flocks as our study system, we measured individual spatial position within a flock as distance to the flock edge. First, we tested the effects of distance to edge on the antipredation cost and foraging benefit of individual goose using generalized linear mixed models (GLMMs). Flock size and number of neighbors and their interactions with distance to edge were included as fixed effects in GLMMs. Then we used piecewise regression to determine the threshold value of distance to edge to classify central and peripheral individuals. Our results indicated distance to edge significantly affected percent of time spent on vigilance (vigilance time), percent of time spent on foraging (foraging time) and intake rate (pecks/min), whereas other factors had no effects. We found that the critical distance that predicted changes in behavior was around 2.5 ​m. Birds 2.5 ​m or less from the edge of the group were more vigilant, and had less efficient foraging than more central individuals. Behavioral differences between central and peripheral individuals were more easily detected when the birds were classified by the method introduced in this study than by the traditional minimum convex polygon method. Our research provides researchers a dichotomous classification scheme that places individuals into peripheral and central positions from an individual's perspective. [ABSTRACT FROM AUTHOR]