The current study aimed to select the strains of lactic acid bacteria (LAB) isolated from forage cactus plants and silage and assess their effects on silage fermentation and aerobic stability. Forty wild isolates from plant and cactus silage, classified as LAB, were evaluated for metabolite production and identified by 16S ribosomal DNA sequencing. These wild isolates were identified asLactobacillus plantarum,Weissella cibaria,Weissella confusaandWeissella paramesenteroidesand the LAB populations differed among the silage. The use of microbial inoculants did not influence gas or effluent losses in forage cactus silage. The silage inoculated with the microbial strain GP15 showed the highest number of LAB populations. The amounts of water-soluble carbohydrates (WSC) and ammonia nitrogen differed among the silage. The silage inoculated with the GP1 strain presented the highest WSC. Populations of enterobacteria and yeasts and moulds were below the minimum detection limit (<2.0 log cfu/g silage) in all the silage studied. The predominant action of inoculants was to maximize dry matter recovery of the silage, which could be the criterion adopted to select the strains of LAB for use as inoculants inOpuntiasilage.

The use of adapted breeds, such as Santa Inês, is of paramount importance for regions with high temperatures because they develop efficient mechanisms for heat dissipation. Furthermore, some breeds have physiological adaptations, such as more efficient mechanisms for the digestion of fibrous foods (e.g. Rabo Largo), which can reduce the harmful effects of semiarid environments. We studied the ingestive behaviour, water consumption, and physiological parameters during feeding of two native sheep breeds fed diets containing high (700 g/kg DM; HC diet) or low (300 g/kg DM; LC diet) percentages of concentrates, based on dry matter (DM). A total of 40 uncastrated male lambs (20 Rabo Largo [breed 1] and 20 Santa Inês [breed 2], with an average body weight of 16.68 ± 2.78 kg, and 19.29 kg ± 3.28 kg, respectively), were distributed in a randomised block design in a two-by-two factorial scheme (breeds × diets) with 10 repetitions. Santa Inês lambs consumed and ruminated DM (P = 0.029 for both) and neutral detergent fibre (NDF; P = 0.001 and P = 0.004, respectively) more efficiently than RaboLargo lambs, while the latter showed an increase in respiratory rate (+19 breaths/min) and rectal temperature (+1.3 °C) compared to the Santa Inês lambs (P = 0.001). The HC diet negatively affected (P < 0.05) the feeding behaviour of the animals, reflecting the higher (P < 0.05) water consumption. The results showed that diets rich in concentrate negatively affected the thermoregulation of lambs. Santa Inês have greater feed and thermoregulatory efficiency than Rabo Largo lambs under conditions of heat stress in the feedlot.

The aim of the present study was to evaluate the agronomic traits in the pre- and post-grazing and the nitrogen use efficiency of Piatã grass that was subjected to nitrogen fertilization throughout the seasons of the year. The experiment was performed in a randomized block design with four treatments (0, 150, 300, and 450 kg ha⁻¹ N). Grazing was performed with sheep when the forage canopy reached 95% light interception up to 20 cm height of post-grazing. The pre-grazing forage mass of the Piatã grass showed a behavior (p < 0.05) linear to nitrogen fertilization, with higher and lower values in spring and winter, respectively. The post-grazing forage mass responded linearly (p < 0.05) to nitrogen fertilization, with an increase of 43.12% for the dose of 450 kg ha⁻¹ N in relation to pastures without nitrogen fertilization. When the non-fertilized pasture was compared with the highest nitrogen dose, a reduction of 21.79% dead tissue was observed in the post-grazing forage mass. The highest nitrogen use efficiency was obtained with the dose of 450 kg ha⁻¹ N. The forage mass production of the Piatã grass in the pre- and post-grazing conditions are positively influenced by nitrogen fertilization and the seasons of the year, with lower values in winter.

The aim of the present study was to evaluate the fermentative profile, chemical composition, and in situ degradability of total mixed ration silage with or without babassu byproducts formulated for sheep diets. The experiment was performed in a completely randomized design, with four treatments (silages) and five replications (silos). The treatments were SS: sugarcane silage (control); SSCS: sugarcane silage with corn and soybean meal; SSBF: sugarcane silage with corn, soybean meal, and babassu flour; and SSBC: sugarcane silage with corn, soybean meal, and babassu cake. The experimental diets were formulated to be isoprotein, and to meet the nutritional requirements of confined sheep with an average weight of 20 kg, according to Nutrient Requirements of Small Ruminants. The SSCS, SSBF, and SSBC treatments presented the highest values of dry matter recovery (83.74, 82.08, and 83.92%, respectively), and higher dry matter (349.07, 344,39, and 352.32 g/kg, respectively), crude protein (151.19, 136.98, and 142.14 g/kg DM, respectively), and non-fibrous carbohydrate (444.70, 353.40, and 371.30 g/kg DM, respectively) contents than the SS treatment. The largest degradations of DM, CP, and neutral detergent fiber in each treatment occurred at 72 h, in which the SSCS treatments presented the highest degradations in comparison to the others (80.59, 87.89, and 55.68, respectively). The inclusion of babassu byproducts in sugarcane silages in the form of total ration acted positively in the qualitative indicators of the silages, improving the fermentation profile and reducing losses, as well as improving the chemical composition and in situ degradability.