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Due to their sensitivity to high temperatures, heat stress effects are prevalent in highyielding dairy cows. To reduce uncertainty in the influence of heat stress, detailed representative and individual animal measurements should be considered. Therefore, the overall objective of this study was to investigate the influence of heat load on the respiration rate (RR) of lactating dairy cows housed in naturally ventilated barns under different climatic conditions and management systems. In the first part of the study, the RR of lactating dairy cows in Germany was investigated hourly, with the aim of evaluating the effects of the temperature-humidity index (THI) on the cows’ responses considering the differences between standing and lying cows and daily milk yield as covariables in the analysis. The consideration of cow-related factors provided evidence for reducing the uncertainty in the heat stress assessment of dairy cows. In detail, with THI below 80, the RR in lying cows tended to be 8 bpm higher than that in standing cows, and the RR in high-yielding cows increased one bpm for each additional kilogram of milk produced per day. Although the first paper showed evidence of cow-related factors influencing RR in cows housed in naturally ventilated barns in a moderate climate, it remained unclear whether the same effect would be observed in high-yielding dairy cows housed under hot climate and high humidity conditions but supplied with cooling management systems for body stabilization. Therefore, in a second part of the study, the aim was to investigate the RR responses of high-yielding dairy cows cooled at two different frequencies per day (3 cooling sessions vs. 8 cooling sessions) and analyze the differences in the RR according to body posture (standing vs. lying), daily milk yield and coat color (black, mixed and white). As noted in the first part of the study, hourly RR measurements were also applied to the second study, which was conducted in Israel during the summer season. The results of this study demonstrated that heat-stressed cows receiving eight cooling sessions per day showed an average RR 14 bpm less than that of cows that received three cooling sessions. Additionally, the cows cooled eight times per day demonstrated a heat accumulation delay of approximately two hours in their RR response. Unlike the experiment in Germany, the Israeli experiment, which was conducted in a hot and humid climatic region, showed a RR 9 bpm higher in standing cows than in lying cows. Daily milk yield also appeared to be an influencing factor on the RR, whereby the cows tended to increase their RR by one bpm per every five kilograms of additional milk produced per day. In addition, the RR (in bpm) in early-lactation cows was 17% higher than that in late-lactation cows. Overall, this study demonstrated that hourly RR measurements improve the reliability of heat stress assessments in dairy cows. Future research should consider the efficiency of evaporative cooling in dairy husbandry considering energy consumption, labor expenditure, animal management and welfare. In addition, other cow-related factors should be evaluated in further research to verify influences on the physiological responses of lactating dairy cows under heat stress conditions and in different cooling strategies., Aufgrund der Empfindlichkeit von Kühen gegenüber hoher Temperaturen sind Wärmebelastungseffekte bei Hochleistungsmilchkühen relevant. Um die Unsicherheit der Einflüsse dieser Auswirkungen zu verringern, sollten detailliertere repräsentative Messungen am Tier in Betracht gezogen werden. Deshalb war das übergeordnete Ziel dieser Arbeit, den Einfluss der Wärmebelastung auf die Atmungsfrequenz (RR) bei laktierenden Milchkühen in frei gelüfteten Ställen in verschiedenen Klimazonen und Managementsystemen zu untersuchen. In der ersten Studie wurde die RR stündlich bei laktierenden Milchkühen in Deutschland mit dem Ziel untersucht, die Auswirkungen des Temperatur-Luftfeuchtigkeits-Index (THI) auf Reaktion der Kühe unter Berücksichtigung der Unterschiede zwischen stehenden und liegenden Kühen und der täglichen Milchleistung als Co-Variablen in der Analyse zu bewerten. Die Berücksichtigung kuhindividueller Faktoren in der Auswertung liefert Hinweise, dass sich dadurch die Unsicherheit der Beurteilung der Wärmebelastung von Milchkühen verringert. Bei einem THI unter 80 war die RR bei liegenden Kühen 8 Atemzüge pro Minute höher als bei stehenden Kühen. Bei Kühen mit hoher Milchleistung erhöhte sich die RR um einen Atemzug pro Minute für jedes zusätzliche Kilogramm Milch, das pro Tag erzeugt wurde. Die erste Veröffentlichung hat gezeigt, dass kuhindividuelle Faktoren die RR bei Kühen in frei gelüfteten Ställen in einem gemäßigten Klima beeinflussen. Ob derselbe Effekt jedoch auch bei Milchkühen mit hoher Milchleistung bei heißem Klima und hoher Luftfeuchtigkeit, und zusätzlichem Kühlungssysteme, welche die Verdunstung verbessern und damit der Erfrischung, beobachtet werden kann, blieb unklar. Daher bestand das Ziel der zweiten Studie zum einen darin, die RR-Reaktionen von Hochleistungsmilchkühen zu untersuchen, bei denen zwei unterschiedliche Kühlfrequenzen pro Tag (3 Abkühlungen pro Tag vs. 8 Abkühlungen pro Tag) angewandt wurden, und zum anderen darin, die Unterschiede in der RR hinsichtlich der Körperhaltung (stehend vs. liegend), der täglichen Milchleistung und der Fellfarbe (schwarz, gemischt und weiß) zu betrachten. Wie bereits in der ersten Studie, wurden auch in der zweiten Studie stündliche Atemfrequenzmessungen an den Kühen während des Sommers durchgeführt, dieses Mal in Israel. Die Ergebnisse dieser Studie zeigten, dass bei wärmebelasteten Kühen, die achtmal statt dreimal eine Kühlung pro Tag erhielten, die RR durchschnittlich 14 Atemzüge pro Minute geringer war. Zusätzlich zeigten die Kühe, die achtmal am Tag gekühlt wurden, in ihren RRReaktionen eine Wärmestauverzögerung von etwa zwei Stunden. Im Gegensatz zu der Untersuchung, die in Deutschland durchgeführt wurde, zeigte die Untersuchung in Israel unter heißen und feuchten Klimabedingungen, dass die RR bei stehenden Kühen im Vergleich zu liegenden Kühen neun Atemzüge pro Minute höher war. Die tägliche Milchleistung wirkte sich zusätzlich als Einflussfaktor auf die RR aus, wobei die Kühe tendenziell ihre RR um einen Atemzug pro Minute für je fünf Kilogramm mehr der durchschnittlichen Milchproduktion pro Tag erhöhten. Darüber hinaus war die RR bei frisch laktierenden Kühen um 17% höher als bei spätlaktierenden Kühen. Insgesamt zeigten diese zwei Studien, dass stündliche Atemfrequenzmessungen die Zuverlässigkeit von Wärmebelastungsbewertungen bei Milchkühen verbessern. Zukünftige Hitzestressuntersuchungen müssen die Effizienz der Verdunstungskühlung in der Milchviehhaltung an Hand von Energieverbrauch, Arbeitsaufwand, Tiermanagement und Tierwohl berücksichtigen. Zusätzlich könnten andere kuhindividuelle Faktoren in weiteren Forschungsarbeiten ausgewertet werden, um den Einfluss von Wärmebelastungsbedingungen und verschiedenen Kühlungsstrategien auf die physiologischen Reaktionen von laktierenden Milchkühen zu überprüfen.

The aim of this study was to evaluate the effects of evaporative cooling at two different frequen-cies per day on the respiration rate (rr) of lactating dairy cows, considering cow-related factors. twenty multiparous israeli holstein dairy cows housed in a naturally ventilated cowshed were di-vided randomly into two treatment groups. the cows of both groups were exposed to 3 or 8 cooling sessions per day (3xcool vs. 8xcool, respectively). the rr was observed hourly, with a maximum of 12 measurements per day. Body posture (standing vs. lying) was simultaneously documented. milk yield was recorded daily. coat color was determined from a digital photograph. the rr of standing and lying cows was lower in the 8xcool group (60.2 and 51.6 breaths per min (bpm), re-spectively) than in the 3xcool group (73.1 and 65.6 bpm, respectively). For each increment of five kilograms of milk produced, rr increased by one bpm, and the rr of cows in early days in milk (dim) was 12.3 bpm higher than that of cows in late dim. in conclusion, eight cooling sessions per day instead of three lead to a rr abatement in heat-stressed cows under hot conditions, and cow-related factors directly impact the rr during heat stress assessment

There is strong upswing in conservation and restoration efforts in Latin America (LA), particularly in the recent decades after several countries have committed to international agreements such as the Aichi targets of the Convention on Biological Diversity, Initiative 20×20, and the Bonn Challenge. To fulfill these agreements, the practice of ecological restoration has to be defined based on ecological knowledge, but also on the specific social, economic, and legal aspects of each country in the region. Here, we give some examples about the national understanding of ecological restoration in 10 countries of LA. We identify difficulties and opportunities to define restoration priorities and needs, and discuss some approaches to cope with economic constraints and agreements, including the potential role of restoration networks in this process. On the basis of the socioecological complexity of these countries and the expectations they have in relation to restoration, we proposed four approaches to guide restoration practice and policy in the region: (1) including biodiversity and ecosystem services approach into ecosystem restoration initiatives; (2) promoting restoration in their frequently human-modified landscapes; (3) accounting for cost–benefit trade-offs; and (4) assembling “horizontal” communication frameworks. These approaches should be based at national levels, but adapted to local-regional levels, in a bottom-up perspective. We consider that national and international restoration networks in the region can help to overcome difficulties, fostering a solid scientific community, helping to develop national approaches that better match the specific conditions of each country and enhancing communication among different groups of stakeholders. Fil: Meli, Paula. Natura y Ecosistemas Mexicanos; México. Universidade de Sao Paulo; Brasil Fil: Herrera, Francisco F.. Instituto Venezolano de Investigaciones Científicas; Venezuela Fil: Melo, Felipe. Universidade Federal de Pernambuco; Brasil Fil: Pinto, Severino. Centro de Pesquisas Ambientais do Nordeste; Brasil Fil: Aguirre, Nicolay. Universidad Nacional de Loja; Ecuador Fil: Musálem, Karim. Centro de Investigación del Chaco Americano; Paraguay Fil: Minaverry, Clara María. Universidad de Buenos Aires. Facultad de Derecho. Instituto de Investigaciones Jurídicas y Sociales ; Argentina. Universidad Nacional de Luján. Instituto de Ecología y Desarrollo Sustentable. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ecología y Desarrollo Sustentable; Argentina Fil: Ramírez, Wilson. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt; Colombia Fil: Brancalion, Pedro H. S.. Universidade de Sao Paulo; Brasil

Our international, interdisciplinary team develops an integrated model to support sustainable, regional and animal-specific adaptation of naturally ventilated dairy barns to climate change. We link numeric models with different temporal and spatial scales and cross-validate with on-farm data and lab experiments.

In the last decades, a global warming trend was observed. Along with the temperature increase, modifications in the humidity and wind regime amplify the regional and local impacts on livestock husbandry. Direct impacts include the occurrence of climatic stress conditions. In Europe, cows are economically highly relevant and are mainly kept in naturally ventilated buildings that are most susceptible to climate change. The high-yielding cows are particularly vulnerable to heat stress. Modifications in housing management are the main measures taken to improve the ability of livestock to cope with these conditions. Measures are typically taken in direct reaction to uncomfortable conditions instead of in anticipation of a long-term risk for climatic stress. Measures that balance welfare, environmental and economic issues are barely investigated in the context of climate change and are thus almost not available for commercial farms. Quantitative analysis of the climate change impacts on animal welfare and linked economic and environmental factors is rare. Therefore, we used a numerical modeling approach to estimate the future heat stress risk in such dairy cattle husbandry systems. The indoor climate was monitored inside three reference barns in central Europe and the Mediterranean regions. An artificial neuronal network (ANN) was trained to relate the outdoor weather conditions provided by official meteorological weather stations to the measured indoor microclimate. Subsequently, this ANN model was driven by an ensemble of regional climate model projections with three different greenhouse gas concentration scenarios. For the evaluation of the heat stress risk, we considered the number and duration of heat stress events. Based on the changes in the heat stress events, various economic and environmental impacts were estimated. The impacts of the projected increase in heat stress risk varied among the barns due to different locations and designs as well as the anticipated climate change (considering different climate models and future greenhouse gas concentrations). There was an overall increasing trend in number and duration of heat stress events. At the end of the century, the number of annual stress events can be expected to increase by up to 2000, while the average duration of the events increases by up to 22 h compared to the end of the last century. This implies strong impacts on economics, environment and animal welfare and an urgent need for mid-term adaptation strategies. We anticipated that up to one-tenth of all hours of a year, correspondingly one-third of all days, will be classified as critical heat stress conditions. Due to heat stress, milk yield may decrease by about 2.8 % relative to the present European milk yield, and farmers may expect financial losses in the summer season of about 5.4 % of their monthly income. In addition, an increasing demand for emission reduction measures must be expected, as an emission increase of about 16 Gg of ammonia and 0.1 Gg of methane per year can be expected under the anticipated heat stress conditions. The cattle respiration rate increases by up to 60 %, and the standing time may be prolonged by 1 h. This causes health issues and increases the probability of medical treatments. The various impacts imply feedback loops in the climate system which are presently underexplored. Hence, future in-depth studies on the different impacts and adaptation options at different stress levels are highly recommended.