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Intensive production systems require high-yield genetics as obtained in Bos taurus x Bos indicus crossbreeding. Generally, high-producing taurine cattle are more susceptible to parasites and heat stress. This study evaluated animal performance, heat-stress measurement (infrared temperatures) and internal parasite infection with daily weight gain in heifers from two genetic groups (Nelore and F1 - Nelore x Angus) reared in two forage production systems (with or without crop-livestock system) during one year. The main objectives were determine the relationship between infrared measures and animal performance and whether it differ between genetic groups and environments. Thirty-six heifers were randomly assigned to two forage production systems, one considered as high-input system with crop-livestock system and other exclusive livestock system considered as low-input. At each 28 days, infrared temperatures (IR), weight and internal parasite infection (fecal egg count) were measured. The temperatures of the eye, snout, forehead, dewlap, body, ground and squeeze chute were determined. F1 heifers had higher weight gain than Nelore (P<0.05) and both did not differ in internal parasite infection (P>0.05). F1 heifers had higher IR than Nelore (P<0.05). The main body points that differentiate between genetic groups were dewlap, forehead and eye. Higher dewlap IR temperature (DW) was associated with higher average daily gain (ADG) during dry season (independently of genetic groups) (ADG = -0.755 + 0.032*DW; R2=0.44). Otherwise, the IR temperatures had a negative relationship with ADG during rainy season and low forehead IR temperature was related to higher average daily gain (ADG = 1.81 - 0.033*forehead; R2=0.12 for F1 animals and ADG = 1.46 - 0.025*forehead; R2=0.07 for Nelore). The infrared temperatures were more related to animal performance during the dry season, which had high temperature and low humidity. The infrared temperatures were able to identify the animal response to the environment challenge. Animals with higher temperatures (dewlap and forehead) had higher daily gain during the dry season.

In the western region of the State of Goias family farmers that depend onthe raising of livestock as one of their main sources of income are predominant. These farmers periodically grow maize for the production of silage in order to compensate their incomes. Considering the high cost of hybrid seeds and nitrogen fertilization, technologies that contribute to the reduction of silage production costs are required. In this sense, the objective of this study was to evaluate the response of maize genetic materials (Feroz Hybrid VIP3 and varieties SCS 156 and SCS 154), regarding silage production, bromatological composition and economic viability when inoculated with Azospirillum brasilense. The experiment was carried out on strips using a completely randomized design with four replications. Each cultivar responded differently to inoculation. For the Feroz hybrid and SCS 156 variety, the use of Azospirillum provided increases of 13.1% and 42.1% in green stem mass and 11.2 and 30.3% in silage nitrogen content, influencing the nutritional composition of the bulky food produced. For the SCS 154 variety, there was no response to inoculation. As for the economic viability, the use of inoculated SCS 156 variety presents a better rate of rentability, proving to be more economically attractive and viable to farmers.

The Brazilian Cerrado is a highland tropical savanna considered a biodiversity hotspot with many endemic species of plants and animals. Over the years, most of the native areas of this biome became arable areas, and with inadequate management, some are nowadays at varying levels of degradation stage. Crop-livestock integrated systems (CLIS) are one option for the recovery of areas in degradation, improving the physicochemical and biological characteristics of the soil while increasing income and mitigating risks due to product diversification. Little is known about the effect of CLIS on the soil microbial community. Therefore, we perform this pilot case study to support further research on recovering degraded areas. The bacterial and fungal soil communities in the area with CLIS were compared to an area under moderate recovery (low-input recovering - LI) and native savanna (NS) area. Bacterial and fungal communities were investigated by 16S and ITS rRNA gene sequencing (deep rRNA sequencing). Ktedonobacteraceae and AD3 families were found predominantly in LI, confirming the relationship of the members of the Chloroflexi phylum in challenging environmental conditions, which can be evidenced in LI. The CLIS soil presented 63 exclusive bacterial families that were not found in LI or NS and presented a higher bacterial richness, which can be related to good land management. The NS area shared 21 and 6 families with CLIS and LI, respectively, suggesting that the intervention method used in the analyzed period brings microbial diversity closer to the conditions of the native area, demonstrating a trend of approximation between NS and CLIS even in the short term. The most abundant fungal phylum in NS treatment was Basidiomycota and Mucoromycota, whereas Ascomycota predominated in CLIS and LI. The fungal community needs more time to recover and to approximate from the native area than the bacterial community. However, according to the analysis of bacteria, the CLIS area behaved differently from the LI area, showing that this treatment induces a faster response to the increase in species richness, tending to more accelerated recovery. Results obtained herein encourage CLIS as a sustainable alternative for recovery and production in degraded areas.