The study of factors influencing animal intake can provide a better understanding of the dynamics of the pasture ecosystem and serve as a basis for managing livestock in a more efficient way. We measured different sward surface heights of tall fescue in the process of short-term intake rate of sheep. There was a significant effect of sward surface height on herbage mass ( P < 0.001), leaf lamina mass ( P < 0.001), other species mass ( P = 0.02), bite mass ( P = 0.01) and short-term intake rate ( P = 0.03) of sheep. There was a quadratic fit between time per bite and bite mass ( P = 0.006). Multivariate analysis showed that the short-term intake rate and bite mass were positively correlated (r = 0.97), bite rate and total jaw movement rate were positively correlated but both were negatively correlated with time per bite. The sward surface height of tall fescue corresponding to the maximum short-term herbage intake rate was 22.3 cm. The underlying processes were driven by the bite mass, which was influenced by the leaf lamina bulk density and its consequences upon time per bite. This sward surface height can be adopted as a pre-grazing target for rotational stocking systems to optimize sheep nutrition on pastures.

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Weed competition on soybean (Glycine max) growth and yield was expected to be different when managed in an agroforestry system as compared with sole-cropping without trees. Therefore agronomic practices to control weeds might need to be modified in agroforestry systems. We analyzed weed competition effects on soybean growth, grain yield, and yield components at different distances from 4year-old eucalyptus (Eucalyptus benthamii) in an alley cropping system, as well as in a sole-crop system in southern Brazil. Above-ground soybean biomass was collected throughout the growing season and a logistic function was used to model crop growth. Weed above-ground biomass sampled during the soybean cycle, and grain yield and yield components at the end of the growing season were evaluated using regression analysis across positions between tree lines, and results compared to those without influence of trees. Soybean yield components were mostly reduced between tree lines compared with sole-cropping without trees. Soybean growth and yield within the eucalyptus agroforestry system was not affected by weed competition. However, weeds reduced soybean growth and yield in sole-cropping without trees. Reduction in soybean yield in the agroforestry system was rather caused by competition from trees. Therefore, tree interference may limit both weed and soybean growth potential.

-White clover is tolerant to many herbicides, making difficult a chemical control of this species during soybean crop establishments. The objective of this research was to select herbicides applied postemergence to control white clover in soybean and know the effects of this control on soybean yield. Seven herbicides were assessed, applied postemergence, with or without sequential application of glyphosate, and two control treatments (no control and total control of white clover). Glyphosate (with two sequential applications), fomesafen (with a sequential application of glyphosate), chlorimuron-ethyl and lactofen have shown a satisfactory control of white clover (above 80%). The lower control efficiency has resulted in lower production of soybeans.Keywords: herbicide, Integrated Crop-Livestock System, interference, Trifolium repens, Glycine max. RESUMO -O trevo-branco apresenta tolerância a diversos herbicidas, o que torna difícil o controle químico dessa espécie durante o estabelecimento da cultura da soja. Os objetivos desta pesquisa foram selecionar herbicidas utilizados em pós-emergência que controlam o trevo-branco na cultura da soja e conhecer os efeitos desse controle na produtividade da soja. Foram avaliados sete herbicidas aplicados em pós-emergência, com ou sem aplicação sequencial de glyphosate, e dois tratamentos testemunhas (sem controle e controle total do trevo-branco

Closely integrated crop and livestock production systems used to be the rule in agriculture before the industrial revolution. However, agricultural landscapes have undergone a massive intensification process in recent decades. This trajectory has led to uniform landscapes of specialized cropping systems or consolidated zones of intensive livestock production. Loss of diversity is at the core of increasing side effects on the environment from agriculture. The unintended consequences of specialization demand the reconciliation of food production with environmental quality. We argue that the reconnection of grazing livestock to specialized crop landscapes can restore decoupled biogeochemical cycles and reintroduce the necessary complexity to restore ecosystem functioning. Besides, the reconnection of crops and livestock promotes several ecosystem services underlying multifunctionality. We focus on the capacity of integrated crop-livestock systems to create biophysical and socioeconomic resilience that cope with weather and market oscillations. We present examples of redesigned landscapes that leverage grazing animals to optimize food production per unit of land while mitigating the externalities of specialized agriculture. We also debate mindset barriers to the shift of current specialization trends toward the design of multifunctional landscapes.

We assessed the effects of high-intensity and low-frequency (HILF) vs. low-intensity and high-frequency (LIHF) grazing on herbage production and performance of beef cattle grazing sorghum pastures. The experimental design was a complete randomized block with two treatments and four replicates (paddocks), carried out in 2014/15. The management target of 50 and 30 cm for pre- and post-grazing, respectively, a LIHF grazing management strategy oriented to maximize beef cattle herbage intake per unit time, was compared with a HILF grazing management strategy of 80 and 20 cm for pre- and post-grazing, respectively, aiming to maximize herbage accumulation and harvest efficiency. Sixteen Brangus steers of 15-month-old and 265 ± 21 kg of live weight (LW) were randomly distributed to paddocks (experimental units). The LIHF resulted in shorter rest periods when compared with the HILF. The greater leaf lamina mass in LIHF allowed greater sward light interception at post-grazing, resulting in greater total herbage production than HILF (7581 and 4154 kg DM/ha, respectively). The average daily gain (ADG) of steers was greater for the LIHF than for the HILF treatment (0.950 and 0.702 kg/animal, respectively); however, even with a greater stocking rate in the HILF, there was no difference for LW gain per ha, with an average of 4 kg LW/ha/day. Our findings demonstrated that the LIHF strategy that is based on offering to the animals an optimal sward structure to favor the maximum herbage intake rate fosters greater herbage production, harvesting efficiency, and ADG without compromising LW gain per area of beef steers, despite the lower herbage harvested per stocking cycle.

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