Thermographic Profiles in Livestock Systems under Full Sun and Shaded Pastures during an Extreme Climate Event in the Eastern Amazon, Brazil: El Niño of 2023

Abstract

The El Niño represents a substantial threat to pastures, affecting the availability of water, forage and compromising the sustainability of grazing areas, especially in the northern region of Brazil. Therefore, the objective of this study was to characterize the thermographic profile of three production systems in the Eastern Amazon, Brazil. The study was conducted on a rural cattle farm in Mojuí dos Campos, Pará, Brazil, between August and November 2023. The experiment involved livestock production systems, including traditional, silvopastoral and integrated, with different conditions of shade and access to the bathing area. An infrared thermographic (IRT) camera was used, recording temperatures in different zones, such as areas with trees, pastures with forage and exposed pastures. The highest mean temperatures (p = 0.02) were observed in pastures with full sun from August to November. On the other hand, the lowest average temperatures were recorded in areas shaded by chestnut trees (Bertholletia excelsa). The highest temperature ranges were found in sunny areas and the lowest were recorded in shaded areas. The highest temperatures were observed in the pasture in full sun, while the lowest were recorded in areas shaded by chestnut trees (p < 0.0001). The interaction between the systems and treatments revealed significant temperature differences (p < 0.0001), with the native trees showing an average temperature of 35.9 °C, lower than the grasses and soil, which reached 61.2 °C. This research concludes that, under El Niño in the Eastern Amazon, areas shaded by Brazil nut trees had lower temperatures, demonstrating the effectiveness of shade. Native trees, compared to grasses and soil, showed the ability to create cooler environments, highlighting the positive influence on different species such as sheep, goats and cattle.

Characterization of the Temperament and Reactivity of Nelore Cattle (Bos indicus) Associated with Behavior Scores during Corral Management in the Humid Tropics

“…By analyzing the mean RT and RR between the traditional system and silvopastoral system groups, it was possible to perceive a reduction than when compared to the integrated system, thus suggesting that the presence of shading can benefit the animals due to the reduction of direct exposure to sunlight, positively impacting their physiological performance [ 2 , 5 , 34 , 36 , 37 ].…”

“…The thermograms were analyzed using Flir Tools software, version 6.3, with the Rainbow HC palette selected. The operator used the camera at eye level, always maintaining coherence and without the aid of a tripod, focusing perpendicular to the target, following the methodological guidelines proposed by Silva et al [3] and Silva et al [5]. Very reactive animal Note: Adapted from Fordyce et al [21] and Burrow et al [33].…”

“…Brazil is considered the world’s largest beef exporter, occupying an important position in cattle farming [ 1 ]. In recent years, there has been greater concern on the part of livestock farmers about animal welfare, i.e., how these animals are being treated on farms and the possible impacts on production and consequently on the quality of the final product [ 2 , 3 , 4 , 5 ].…”

Hypothalamic Neuromodulation and Control of the Dermal Surface Temperature of Livestock during Hyperthermia

“…In various circumstances, it has been documented that an increase in the body temperature of animals is associated with warm environmental conditions with high humidity and solar radiation [ 58 ]. Livestock shows a greater susceptibility to thermal stress when exposed to these climatic conditions and when maintained in intensive production systems where growth rates are sought to be maximized.…”