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.

The relationship between the indices of thermal comfort and internal temperature in lactating cows was evaluated inRondônia, western Amazonia in a 2 × 2 crossover trial carried out with eight Girolando cows, ½ Holstein × ½ Gyr (n=4) and – Holstein × ¼ Gyr (n=4), grazing palisade grass supplemented with or without soybean oil concentrates. Data logger thermometers adapted to intravaginal devices (hormone free) were used to measure internal temperatures (IT) every 10 min over 48 h. Concomitantly, environmental parameters (air temperature, relative humidity, wind speed, and solar radiation) were collected for the estimation of the temperature-humidity index (THI), equivalent temperature index (ETI), and predicted respiratory rate (PRR). Supplementation with soybean oil did not affect the internal temperature of the cows. IT varied significantly between the genetic groups, with the highest mean observed at night in the – Holstein × ¼ Gyr cows, compared with that in the ½ Holstein × ½ Gyr cows (39.54 °C vs 39.06 °C, respectively). THI, ETI, and PRR were significantly and positively correlated with the IT of the Girolando cows; however, the PRR was not found to be adequate in indicating the night-time heat stress in cows.

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To evaluate the bromatological composition and ruminal degradability of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of Xaraés palisade grass (Urochloa brizantha ‘Xaraes’ syn Brachiaria brizantha) under grazing in integrated crop, livestock (ICL), and forest (ICLF) systems, we conducted an in situ degradability trial in randomized blocks with three non-lactating 3/4 Gyr × 1/4 Holstein cows, provided with ruminal cannula. The management of Xaraés palisade grass was similar in both systems, differing only regarding shading in the ICLF system provided by eucalyptus trees (average 65% crown cover). Grass samples were incubated for 0, 3, 6, 9, 12, 24, 36, 48, 72, and 96 hours. Considering the passage rate 2% h-1, the Xaraés palisade grass of ICL system had greater NDF effective degradability in relation to ICLF (46.38% vs 44.98%). However, the palisade grass CP potential degradability was greater in the ICLF than in the ICL system (68.92% vs. 65.40%). The presence of trees in the pasture has effect on nutritional traits of the Xaraés palisade grass, increasing its protein content and degradability and reducing its fiber degradability.

This work aimed to evaluate the effect of supplementation with concentrate containing or not soybean oil on rumen degradation of dry mater (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of Marandu grass managed with occupation period of two days with 28 days of rest and 2.6 AU/ha of stocking rate. An in situ trial was carried out with three dry crossbred ¾ Gyr x ¼ Holstein rumen cannulated cows arranged in 3 x 3 crossover design with three treatments: no supplementation (NS), supplementation with non-soybean oil concentrate (NO), supplementation with 7% soybean oil concentrate (SO). Incubation periods were 0, 6, 12, 36, 48 and 96 hours. There was no difference among treatments. The values of potential degradability of DM, NDF and ADF of marandu-grass determined in animals from NS, NO and SO were: 81.80%, 92.12% and 91.54%; 56.05%, 58.60% and 60.21%; 60.01%, 64.34% and 65.17%, respectively. Supplementation with concentrate containing or not 7% of soybean oil do not change rumen degradation parameters of marandu-grass.

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.