Scratching behavior of dairy heifers in agrivoltaic systems with different configurations

This study aimed to evaluate the scratching behavior of dairy heifers in agrivoltaic system with different configuration in a tropical climate. The experiment was conducted between July and August 2025, during 12 consecutive days at FMVZ/Unesp – Botucatu, São Paulo State, Brazil. The scratching behaviours on photovoltaic panel structures of 21 dairy heifers (550 ± 55 days old; 247 ± 37 kg, mean ± SD) were registered continuously from 9h to 16h. In a crossover design, the heifers were divided into three groups (seven heifers/group). The agrivoltaic systems were composed of 72 panels (2.28 × 1.14 m), divided into six paddocks in the center of each paddock, with east–west orientation and facing north, at a fixed height of 2.30 m. In three paddocks, 36 panels (12 panels/paddock) were installed in a vertical position (AGRIver), with panel structures composed of 5 poles in each paddock, whereas in the other three paddocks, 36 panels (12 panels/paddock) were installed in a horizontal position (AGRIhor), with panel structures composed of 10 poles in each paddock. The data were analyzed using a generalized linear mixed model (Poisson family), considering agrivoltaic system and hours as fixed effects, with date and groups as a random effect. The heifers were 33% more likely (p=0.01) to engage in scratching behavior in AGRIhor (193 events) than AGRIver (131 events). There was no effect (p>0.05) of the hours of evaluation within agrivoltaic system. Regardless of agrivoltaic system, the highest frequency (p=0.002) of scratching behavior occurred between 11h-11:59h (81 events). In conclusion, the configuration of the agrivoltaic systems influenced the heifers’ scratching behavior. The horizontal configuration, which had more poles than the vertical configuration, provided more space and may have contributed to the heifers engaging in more scratching behavior.