Belowground Productivity in Patches of Heterogeneous Grass Swards After Nearly Two Decades of Low-Intensity Cattle Grazing

In low-input grassland, patch-grazing leads to tall and short patches that provide different growth conditions for the grass sward. Since belowground biomass and the associated turnover represent the main carbon input to soil in grassland, we investigated within-pasture variation of above- and belowground net primary production in relation to patches over one year of production in a long-term grazing experiment during the year 2022. The analysis of above- and belowground net primary production showed an effect of patch types, partly in interaction with the month, indicating a strong variation due to climatic conditions. In those few cases where differences existed among patches, then tall patches were more productive than short ones. Overall, the experimental year was unusually dry and hot

Real-World Applications for Virtual Fences – What Are Potential Benefits for Conservation?

Livestock grazing can enhance biodiversity and ecosystem services in agricultural landscapes. In many parts of Europe, however, grazing has lost its importance, especially in the dairy sector. Large proportions of permanent grassland have been converted to arable land or intensified by fertilization and frequent defoliation. The disappearance of large herbivores and extensively grazed pastures contributes to the loss of structural, functional and biological diversity and ecosystem services. Modern technologies, which circumvent the cost- and labour-intensive installation of physical fences, could facilitate a precise spatio-temporal management of livestock and promote grazing. We reviewed the literature on the state-of-the-art of virtual fencing, focusing on the prospects of these technologies to enhance environmentally-friendly livestock farming. Novel virtual fencing technologies are expected to entail various ecological benefits, but this has rarely been tested in practice. Future experiments not only need to increase sample sizes and study periods to evaluate the long-term effectiveness of virtual fencing, but also need to be specifically designed for answering questions of conservation interest. Virtual fences have the potential to reconcile agronomic with ecological demands and bring livestock back into the landscape, but whether they will actually find broad application depends on further multidisciplinary research on animal welfare, agronomic, social and legal aspects

Herding Livestock – the Phoenix Rises from the Ashes? Digital Herding as a Future Tool for Grazing Livestock

Today, sustainable management of grazing livestock requires high efforts in management and fencing. Nowadays, several developments in digital technologies for herding grazing animals are arising. We conducted a systematic review on current developments in digital technologies for managing grazing animals within the landscape. We mainly focused on cattle (Bos taurus) and sheep (Ovis aries). We highlight the most promising developments of virtual fencing used in recent research to evaluate effectiveness, animal behaviour and welfare. Moreover, we highlight current research in digital herding by drones and robots. We discuss the potential and current limitations of digital tools for sustainable grazing management. Recent study results showed that virtual fences are highly efficient in keeping cattle within allocated pasture areas. So far, there has been no evidence for harmful impacts on animal welfare or reduction in animal performance. First findings suggest that drones can also herd and move animals. However, knowledge on the efficiency and potential effects on animal welfare when using drones is limited. First findings have shown that robots are able to gather animals to a specific location and heart-rate and blood tests showed that the animals were less stressed by the robot than they were by a human. However, research on herding drones and robots is still in its infancy. Digital tools provide the opportunity for precise livestock movement control and could facilitate the implementation of both productive and biodiversity-friendly grazing

Closing Feed Gaps by Winter Forage Production in Limpopo: What Is the Potential?

In southern Africa, livestock productivity in mixed crop-livestock systems is constrained by forage supply towards the end of the dry period. Opportunities to improve forage availability to close the temporal feed gap counteracting negative effects on production as well as on environment need to be explored. A promising option might be the planting of cover crops (CC) during the winter period. Hence, a field experiment was conducted in the Limpopo province (South Africa) during the autumn-winter period of 2019 at two sites (Syferkuil, Thohoyandu) with contrasting climatic conditions and soil type. We selected multi-functional C3 species – winter rye (Secale cereal L.) intensively used in the temperate region sown as pure stand and established at two sowing dates. We assessed forage production, soil water dynamics and nitrogen accumulation. In a second step, we tested the Agricultural Production Systems simulator (APSIM) model against the field trial data. We present here, preliminary results which show high potential growth when irrigated. Early planting of CC yielded the highest accumulated biomass (18 t DM ha-1 and 7 t DM ha-1 at Syferkuil and Thohoyandu, respectively) after 140 days while delayed planting (4 weeks after first planting) decreased biomass production. The model predictions rely heavily on pedo-climatic interactions which need further improvements

Assessing Feed Gaps on Smallholder Livestock Farms in Limpopo: Production System and Coping Strategies

Smallholder farms in southern Africa are predominantly mixed crop-livestock systems and often characterized by low productivity. Therefore, providing sufficient forage becomes a challenge that results first in feed gaps, i.e. the difference between the demand for and supply of forage, and secondly, in nutrient mining of the soil due to the overuse of the resources. However, the availability of forage follows potentially seasonal patterns. Hence, a key entry point for any intervention strategies for improvement is an assessment of forage quantity and quality throughout the year. Against this background, we investigated six locations, smallholders’ cattle production systems and their adaptation options in periods of feed deficit across three distinct agro-ecological zones in the Limpopo province (South Africa). We interviewed 90 farmers from May to September 2019 and found that farmers struggle in winter-spring (June – September) to access feed resources for their livestock. Most farmers mentioned that feed deficit in that period is a regular phenomenon. Mixed crop-livestock farmers stated that they rely on on-farm resources (crop residues) while sole livestock farmers stated that reducing herd size is a top adaptation option. Farmers also indicated that feed availability in required quantity and quality is the biggest constraint to sustaining livestock production throughout the year. This study demonstrates a sound assessment of the temporal pattern of feed gaps in Limpopo province and potential farmer avenues for their mitigation

Virtual Fencing Predictable for Cattle? A Simple Method to Test Whether and How Fast Cattle Can Learn the Association Between Acoustic Signal and Electric Pulse

Virtual fencing (VF) offers promising future prospects for improved grazing management as it has the potential to simplify fencing. VF lines are easily drawn and shifted via GPS coordinates. A VF collar emits an acoustic signal when the animal approaches the VF line. The signal stops immediately when the animal turns around. If the animal continues to move towards the VF line, a short electric pulse is emitted. A teaching and an operating mode are provided by the VF collars. The animals automatically change mode when they respond correctly to 20 consecutive acoustic signals without receiving an electric pulse. A prerequisite for using the technology is the ability of the grazing animal to learn to predict the electric pulse, therefore we used the time until mode change (from teaching to operating) to evaluate the learning ability and speed of 16 Fleckvieh heifers equally divided into two groups. All heifers were naive to VF prior to the study (conducted 05.07-16.07.2021). On the first day, the two groups were equipped with VF collars (® Nofence, AS, Batnfjordsøra Norway) and assigned to two adjacent pastures. On day eight, the collars were deactivated for a short time and then activated to start in teaching mode again to analyze differences in mode change speed when they were naive to the technology or experienced. The animals remained on the same pasture after reactivation of the collars. We investigated the time to reach theoperating mode (Δ) for each consecutive round (days one and eight) and found a significant difference (p \u3c 0.0001). Average Δ was 49.32 ± 0.41 h and 2.31± 0.41 h for round one and two, respectively. The faster mode change speed of the second round suggested successful learning. Given our study results, cattle learned to predict (and avoid) the electric pulse of VF collars

More Than a Fencing System? Testing the Validity of Virtual Fencing Collars for Animal Monitoring on Pasture

High labour requirements for fencing and animal monitoring appear to be general obstacles for the wider use of pastureland for grazing livestock. Virtual fencing (VF) enables a less laborious pasture management. Fence lines can be easily drawn and moved using GPS data. The advantages of VF for reducing the labour inherent to controlled grazing management are obvious. Potential additional animal monitoring opportunities arising from such a VF system that uses real-time GPS data have not yet been studied. Lying is seen as an indicator for assessing comfort or restlessness of cattle. Therefore, we focus on lying behavior in this evaluation. Based on data from conventional GPS collars, lying and standing often cannot be distinguished. The VF collars (® Nofence, AS, Batnfjordsøra Norway) used in this study detect low movement via an integrated accelerometer and then send the same GPS position during this time of low movement, in order to save battery life. We tested whether this battery life save function could be suitable for the detection of lying behavior. To address this question in a two-step-approach, we first compared observational data with IceTag pedometer (IceRobotics Ltd. Edinburgh, Scotland) data. In the second step, the pedometer data were compared to VF collar data via a confusion matrix. With 93% precision, 89% accuracy and 83% recall in this second step, the use of the VF collars can be recommended for a valid measure of lying behavior monitoring on pasture, which would be an added benefit to VF technology

Rotational Stocking with Virtual Fences: Effects on Grassland Diet Digestibility, Livestock Performance and Stress Levels of Heifers

Virtual fencing is an innovative technology for simplified, less laborious dynamic grazing management and remote animal monitoring. The effect of this novel technology on animal welfare is still a matter of debate. Previous research suggests no differences in stress experience responses of cattle between the two fencing systems on continuously stocked pastures. This study investigated differences in diet organic matter digestibility, livestock performance and fecal cortisol metabolite concentrations of heifers on pastures in a rotational grazing system, fenced with a virtual fence (Nofence, Batnfjordsøra Norway) compared to heifers fenced with a traditional electric wire fence. The study was conducted in 8 weeks from July to September 2021 using 32 heifers divided into four groups allocated to the two fencing systems (two replicates). The experimental pasture of each group was subdivided into four paddocks for rotational grazing. Fecal samples were collected the first day and last day on pasture of each rotation period. Grassland herbage samples were taken by hand plucking pre- and post-grazing and analyzed using near infrared reflectance spectroscopy. Heifers were weighed prior to and after each rotation. The results suggest that no differences occur between the two fencing treatments with respect to diet digestibility, livestock performance or stress level, pointing at no trade-off to livestock performance or animal welfare when using virtual fencing

Ab Initio Benchmark Study of Nonadiabatic S₁–S₂ Photodynamics of <i>cis</i>- and <i>trans</i>-Hexatriene

The dynamics of the nonadiabatically coupled lowest singlet excited states of <i>cis</i>- and <i>trans</i>-hexatriene are studied theoretically, in a comprehensive electronic structure and quantum dynamical investigation. At the ground state equilibrium geometry the relevant S₂ and S₁ states carry the A₁ (A_g) and B₂ (B_u) symmetry labels, for the <i>cis</i> (<i>trans</i>) isomer. Various high-level electronic structure methods are used, including the recently reparametrized DFT/MRCI method, and the results are critically compared. Key parameters of interest are the vertical energy gap and the strength of vibronic coupling between the interacting electronic states. To estimate their influence, suitable comparison calculations are performed. The results are used as the basis for quantum dynamical calculations on the UV absorption spectrum and electronic population transfer involving the S₁ and S₂ states. Up to nine nonseparable degrees of freedom are included in the calculations. The experimental UV absorption spectrum in the 5–5.2 eV energy range can be very well reproduced. The time-dependent wavepacket propagations reveal a population transfer on the order of 30–50 fs, which becomes increasingly complete with more degrees of freedom included in the calculation. The results are briefly compared with analogous data for the <i>s</i>-<i>trans</i>-butadiene system treated by some of us recently

Heifers don\u27t care: no evidence of negative impact on animal welfare of growing heifers when using virtual fences compared to physical fences for grazing

Virtual fencing (VF) represents a way to simplify traditional pasture management with its high labour and cost requirements for fencing and to make better use of the \u27beneficial\u27 agronomic and ecological effects of livestock grazing. In this study, the VF technology (® Nofence, AS, Batnfjordsøra Norway) was used with Fleckvieh heifers to investigate possible welfare impacts on the animals compared to conventionally fenced animals when they were trained to respond correctly to the system. The Nofence® collars (attached to the neck of the heifers) send acoustic signals as a warning when the animals approach the VF line, which was set up by GPS coordinates within the Nofence®-App, followed by an electric pulse when they do not stop or return. The heifers had no experience with VF prior to the study. Two treatments (VF versus physical fencing (PF)) were applied to six groups of four heifers each (three groups per treatment) over three 12-day time replicates. One VF line separated the pasture of the VF group into an accessible or non-accessible area. The control group had a PF line. Both groups were equipped with Nofence® collars (deactivated for the PF group). The trial took place on two adjacent paddocks of 1 000 m2 each following a 12-day schedule which was divided into three sections: visual support of the VF line by a physical barrier (first 2 days), only virtual border without visual support, moving the VF line (on day 8). Each time replicate followed the next successively on different paddocks with two new groups of heifers, which were grazed 5 h daily. During the whole experiment, the behaviour of each of the four animals per group was continuously observed; 2 h a.m., 2 h p.m. Exclusion by the VF line was effective in our trial. None of the heifers crossed the virtual boundary, i.e. the time spent in exclusion zone was zero. The heifers received 2.70 ± 2.63 acoustic signals and 0.30 ± 0.36 electric pulses (mean ± SD) per heifer and hour during all time replicates. Main cattle behaviour on pasture was not affected by the fencing system. Live weight gain, herbage consumption and faecal cortisol metabolites also revealed no significant differences. The duration until the heifers restarted grazing after an electric pulse from the Nofence® collar was significantly shorter than after an electric pulse from the physical fence. We can summarise that in our study, cattle well-being on pasture was not negatively affected by VF compared to PF