To compare the integrated crop-livestock-forest (ICLF) and crop-livestock (ICL) systems in relation to thermal comfort and grazing behavior of Girolando heifers, a 2 × 2 crossover trial (two system and two periods) was carried out with eight ¾ Holstein × ¼ Gyr heifers in Xaraés–palisade grass pasture under intermittent stocking with 10 days of occupation period and 20 days of resting. In ICLF, crown cover of eucalyptus planted in rows was 65% at the beginning of the experiment. Animal behavior was assessed through bioacoustics by recording heifers’ sounds for 48 hours. Concomitantly, heifers’ internal temperature (IT,°C) was recorded every 10 min using data logger thermometers adapted to hormone-free intravaginal devices. Air temperature and humidity data were collected by thermohygrometers located in the center of ICLF and ICL for calculating Temperature–Humidity Index (THI). According to THI values, ICLF and ICL did not vary in terms of thermal comfort. However, THI indicated moderate stress (82.26±4.40) during day (06:00 to 17:59h) and mild stress (75.76±4.38) at night (18:00 to 05:59h) in both systems. During day, heifers from ICL had significantly (p < 0.05) higher IT (39.51±0.56oC) than those from ICLF (39.41±0.56oC); the former spent more time grazing and less time drinking water in ICLF (581.35±30.1 and 4.87±1.09 min, respectively) when compared with those from ICL (436.88±28.1 and 10.25±1.09 min, respectively). Therefore, although thermal comfort index did not vary between the systems, under moderate stress, crossbred heifers have lower internal temperatures, resulting in longer diurnal grazing and shorter water drinking time in Eucalyptus-shaded pastures.

RESUMOObjetivou-se validar o método de análise de dados bioacústicos na descrição do comportamento em pastejo de novilhas em área de integração lavoura-pecuária (iLP) e floresta (iLPF). Foram utilizadas oito novilhas Girolando (¾Holandês x ¼Gir) com média de 25±6,8 meses de idade e 268±83kg de peso vivo (PV), distribuídas em delineamento crossover 2x2 (dois sistemas x dois períodos de avaliação). A coleta de dados para análise bioacústica foi realizada utilizando-se gravadores MP3. grazing, rumination, and resting, respectively: 127 vs. 137; 122 vs. 113; and 238 vs. 216 in ICL system and; 134 vs. 103; 130 vs. 165 and 233 vs. 203 (Santana Júnior et al., 2013). Mediante o estudo do comportamento dos animais, é possível apresentar soluções para problemas relacionados com a redução do consumo em épocas críticas para produção de leite (Albrigth, 1993). Os resultados de pesquisas podem descrever os principais problemas que limitam a http://dx

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Aiming to compare integrated crop, livestock (ICL) and forest (ICLF) systems in relation to ingestive behavior of dairy heifers, a 2 × 2 crossover trial was conducted with two periods and two systems. Eight Girolando (3/4holstein × 1/4 Gyr) heifers were evaluated in pasture of Xaraés palisade grass (Urochloa brizantha ‘Xaraes’ syn Brachiaria brizantha) managed with intermittent stocking. The ICLF systemhad eucalyptus trees planted in tiers with 65% crown cover. Ingestive behavior parameters were obtained using acoustic data collected with mP3 recorders for 48hours. Statistical analysis was performed using the mixed procedure of SAS, and means were compared using the Tukey-Kramer test at 5% significance. The dry mater intake (DMI), number of daily grazing sessions, and the duration of the grazing sessions did not differ (P<0.05) between systems. A higher (P<0.05) bite rate and total daily bites and lower (P<0.05) bite mass was observed in the ICLF system in relation to ICL. Heifers in shaded pasture change their ingestive behavior in comparison with those in full-sun pasture.

The effect of soybean oil supplementation in the diet of early lactating Girolando cows under moderate heat stress were studied in a grazing trial. Dry matter intake (DMI), milk yield, feed efficiency, and grazing behavior (during daytime and nighttime) were evaluated in two groups of eight crossbred Girolando (Holstein × Gyr) cows grazing palisade grass (Urochloa brizantha syn. Brachiaria brizantha) with initial means of 53±33 days in lactation and 22.6±3 kg of milk day-1. They were arranged in a 2×2 crossover trial with two supplements (with or without soybean oil), two genetic groups and two periods. During the experimental period, the mean of temperature and humidity index (THI) was 75.11, suggesting moderate heat stress. Total DMI was based on fecal production estimated by LIPE® and the diet in vitro DM digestibility (IVDMD). Grazing behavior was assessed for 48 hours by acoustic data collected with MP3 recorders. Soybean oil supplementation had no significant effects on all variables evaluated in this study. Averages of individual milk yield and total DMI were 19.26 kg day-1 and 15.32 kg DM day-1, respectively. Under moderate heat stress, oil supplementation did not change grazing behavior, dry matter intake, or milk yield in early lactating Girolando cows.