The objective of this study was to evaluate the effect of inclusion of condensed tannins (CT) from black wattle (Acacia mearnsii) on feed intake, ruminal protozoa population, ruminal fermentation, and nutrient digestibility in Jersey steers. Five ruminally-cannulated steers were used in a 5 × 5 Latin square design, with five periods of 20 days each (14 days for diet adaptation and six days for sample collection per period). Treatments were composed of dietary inclusion levels of condensed tannins at 0, 5, 10, 15, and 20 g/kg of diet dry matter. Intakes of dry matter, organic matter, ether extract, crude protein, neutral detergent fiber, and total digestible nutrients were not affected by condensed tannins. The ruminal pH was reduced linearly with tannin levels. Ruminal ammonia nitrogen concentration was not affected by tannins. Tannins reduced the molar proportion of acetate and did not affect the ruminal protozoal population, which might be related to the low doses used. Digestibilities of dry matter, organic matter, and neutral detergent fiber were not altered; however, there was a linear reduction in crude protein digestibility. Based on these results, CT extracts from black wattle are not recommended for improving nutrient utilization in steers at the tested levels.

The objective was to characterize the nutrient and mineral composition of M. maximus cv Aruana grazed by lambs in a silvopastoral system or full sun with added nitrogen. The treatments are: (1) Aruana grazed in full sun with nitrogen fertilization, (2) Aruana grazed in full sun without nitrogen fertilization, (3) Aruana grazed in a silvopastoral system with nitrogen fertilization and (4) Aruana grazed in a silvopastoral system without nitrogen fertilization. The nutrient dynamics, urinary excretion of N and the amount returned of the nutrient were determined from four sheep in a Latin square experimental design; the analysis of the mineral composition of the leaves and stalks of the grass was carried out by collecting samples from the plots used, totaling six in each treatment evaluated. The silvopastoral system provided high levels of P and K in forage plants. Urinary N excretion and urine mineral contents were influenced by the systems evaluated and the use of N fertilizer. N did not show differences for leaves and canes.

The study evaluated the impact of different environmental enrichment strategies on the performance and welfare of commercially raised broilers. The research, conducted in Paraná, Brazil, involved 690 birds allocated to three types of environments: control, with a low wall, and with a perch. The performance of the birds was monitored through indicators such as feed conversion, live weight (plucked and eviscerated), and cut yields (wing, thigh, drumstick, breast, and back weight). There were no significant differences in feed conversion and yields between the environments, except for wing weight, which was higher in environments with a perch for males. Females raised in an environment with a low wall showed higher live and eviscerated weight, while thigh weight was lower in environments with a perch. Welfare variables, such as Latency to Lie and Fluctuating Asymmetry, showed no significant differences between the environments. However, females in the control and low wall environments had a higher incidence of calluses on their feet compared to those in the perch environment. Joint injuries (Hock Health) did not show significant differences between the types of enrichment. These results suggest that, although environmental enrichment may benefit some aspects of welfare, its impact on broiler performance and joint health needs to be better understood, particularly in relation to the long-term effects of different enrichment types on locomotor health, muscle development, and the prevention of joint injuries. Future studies should focus on the physiological mechanisms behind these effects, including the role of enrichment in reducing stress and promoting more natural behaviors that may influence bone density and joint function.

The objective of this work was to evaluate the effects of the use of additives on the ensiling of AGRI 002E sorghum (Sorghum bicolor), focusing on the chemical composition, loss, microbial profile, and fermentative stability of the fodder. Sorghum was harvested 111 days after sowing, chopped, and ensiled in PVC silos under different treatments, as follows: without additives (SS), with inoculant (SSI), with urea (SSU), and with urea and inoculant (SSUI). The silos were opened and analyzed at 1, 3, 7, 14, 28, and 56 days after ensiling. The inclusion of urea and bacterial inoculant did not significantly affect dry matter content, but influenced dry matter recovery and microbial population, reducing the presence of clostridia and fungi. Dry matter and gas losses were minimal, indicating an adequate fermentation. The additives contribute to a more stable fermentation and a better preservation of the ensiled material, particularly by reducing undesirable microbial populations.

O objetivo do presente trabalho foi avaliar o efeito da adubação nitrogenada em M. maximus cv. Aruana cultivado em sistema silvipastoril e pleno sol sobre as características morfogênicas, estruturais, produtivas e composição química. Sistemas silvipastoris promovem eficiência produtiva e sustentabilidade na produção animal, melhorando a forragem e o conforto térmico. A adubação nitrogenada afeta o crescimento de forrageiras tropicais. O estudo avaliou o sistema utilizado (silvipastoril e pleno sol), adubação (com e sem) e períodos (21, 42, 63 e 84 dias) em características produtivas e morfogênicas da forrageira. O sistema silvipastoril elevou a altura do dossel, enquanto o pleno sol favoreceu a matéria seca e ganho de peso animal. A adubação beneficiou a densidade de perfilhos basais e morfogênese. O teor de proteína bruta foi maior no pleno sol. Pleno sol teve vantagens na forragem e composição, enquanto o silvipastoril destacou-se na altura do dossel. A adubação melhorou várias características, incentivando renovação tecidual. O estudo destaca a importância do manejo adequado em sistemas silvipastoris para otimizar produção e qualidade forrageira.