Context: Sorghum (Sorghum bicolor (L.) Moench) grain with low tannin content may be suitable as an alternative to maize (Zea mays L.) grain in ruminant diets in terms of input costs and drought tolerance, and effects on growth performance and mitigation of methane (CH4) emissions. Aims: The study aimed to evaluate the effects of substitution of maize with sorghum grain at different rates on ruminal microbial protein synthesis, CH4 formation and liveweight gain in growing ruminants. Methods: Twenty-five Santa Inês lambs (bodyweight 19.0 ± 1.5 kg) were randomly divided into five dietary treatments. Control diet components (on a dry matter basis) were Tifton-85 hay (400 g/kg), maize (405 g/kg), soybean meal (165 g/kg) and commercial mineral supplement (30 g/kg). Sorghum diets comprised the basal diet with the maize grain proportionately substituted with sorghum grain at 25%, 50%, 75% and 100% (diets S25–S100). Lamb feed intake, growth performance, nutrient digestibility, nitrogen balance, microbial protein synthesis and CH4 emission were measured during an experimental period of 70 days. Key results: Negligible variations of chemical composition were observed among the experimental diets, although numerical increases in condensed tannins were observed with increasing levels of sorghum replacement. There was no significant effect of level of sorghum inclusion on feed intake. Partial substitution of maize with sorghum grain increased lamb average daily gain linearly (P = 0.02) and quadratically (P = 0.002) compared with diets based on either grain alone, with the S50 lambs having the highest values. A linear decrease in dry matter digestibility (P = 0.02), organic matter (P = 0.02) and acid detergent fibre (P = 0.002) was observed for lambs receiving sorghum diets compared with the control. A significant linear (P = 0.023) effect was observed for retained nitrogen (g/day), with lambs fed S25 and S50 having higher values than those in other treatments. All partially substituted diets (S25, S50 and S75) reduced CH4 per unit bodyweight gain in a linear trend (P = 0.03), by 35%, 29% and 33%, respectively, and tended to increase (linear effect, P = 0.09) the calculated amounts of absorbed microbial protein compared with the control diet. Conclusions: Low tannin sorghum grains can replace maize grains by up to 75% to maximise ruminal microbial biomass production for optimal lamb growth performance and reduced CH4 emission. Implications: Animal productivity can be enhanced while mitigating the environmental impact of livestock production through the partial substitution of maize by low tannin sorghum grains in ruminant diets.

The purpose of this work was to evaluate Phorbol Ester’s (PE), Total Fenols (TF), Total Tannins (TT), Condensed Tannins (CT), Saponins Content (SPN), amino acids profiles and apparent digestibility of detoxicated Jatropha curcas meal in finishing pigs diets, as well as biogas and methane production by the manure from cross-bred pigs fed this meal. Apparent digestibility coefficients of Dry Matter (DM), Crude Energy (CE), Crude Protein (CP), Crude Fiber (CF) and Ether Extract (EE) were evaluated. Twenty crossbreed pigs with 70±1.95 kg initial weight were allotted in individual metabolic cages, according to body weight in a Complete Randomized Block Design with ten replications per treatment. On the last day of the adaptation phase of the digestibility experiment, the manure were collected and put it in bottles with hydraulic retention time of seven days for further evaluation of biogas and methane produced in liters and liters % of total solids. The content of PE, TF, TT, CT, SPN, were, respectively, 0.06 mg/g, 26.08 and 10.43 equivalent gram of tannic acid, 0.05 equivalent gram of leucocyanidin and 0.005%. The results of apparent digestibility coefficients were 83.80% (DM), 3.500 kcal/kg (CE), 13.45% (CP), 1.5% (CF) and 2.3% (EE). Regarding the generation of biogas and methane of manure from pigs fed detoxified Jatropha curcas meal, biogas production (1201.4, 1089.3 mL/g Total Solids) and methane (246.7 and 218.2 mL/g Total Solids) from manure weren't significantly different (p>0.05) between the treatments. So, concludes that detoxicated Jatropha curcas meal is a promising by-product due its nutritional composition and metabolic response which may be used in finishing pig diets without affecting the generation of renewable energy.

Two experiments were conducted to evaluate digestibility, performance and carcass traits of finishing pigs fed fibrous diets, such as, basal diet (Control treatment) and inclusion of Tifton-85 hay, Soybean hulls or Citrus pulp. Twenty crossbred castrated male pigs, with average body weight of 70.00±1.95 kg, distributed in a randomized block design with four treatments and five repetitions (blocks) were used to evaluate apparent total tract digestibility of dietary nutrients. To evaluate animal performance and carcass traits, eighty commercial hybrids pigs with 120 days of age and average body weight of 73.00±3.3 kg were used. Pigs were distributed in 40 boxes according to gender and body weight, with one castrated male and one female pig per pen (experimental unit), in a randomized block design with 10 repetitions (blocks) per treatment were used. Regarding the digestibility assay, Tifton hay presented 2425 kcal of digestible energy/kg, with low digestible protein content (3.36%). Citrus pulp presented 2850 kcal of digestible energy/kg, also with low digestible protein content (1.47%). Soybean hulls showed 2250 kcal of digestible energy/kg, with relatively medium crude protein digestibility coefficient (7.85%). Offering different fiber sources in the finishing phase for pigs promoted significant differences (p0.05) was observed for carcass parameters. Given the results obtained in this study, Soybean hull showed to be a promising ingredient to be used in diets of finishing pigs, leading to good results on animal performance and also contributing to the sustainability of pig production.

This study evaluated the effects of dietary guarana ( Paullinia cupana var. sorbilis ) powder as a feed additive for finishing pigs. A 12-day digestibility trial was conducted with 20 barrows (61.8 ± 1.9 kg) distributed in a randomized block design with four dietary inclusion levels of guarana (0%, 1%, 2%, and 4%). In addition, a 30-day performance trial was conducted, with 96 pigs assigned to diets containing 0%, 1%, 2%, and 3% guarana. The growth performance parameters, including the average daily feed intake (ADFI), the average daily gain (ADG), and the gain-to-feed (G/F) ratio, as well as the carcass traits, were evaluated. Guarana inclusion did not affect the apparent digestibility coefficients of dry matter, crude energy, or crude protein ( p > 0.05). However, increasing dietary guarana levels significantly affected growth performance, with linear reductions in ADFI and ADG ( p ≤ 0.05), while the G/F ratio increased linearly. Quadratic responses were observed for hot carcass yield, cold carcass yield, loin eye area, and fat-to-meat ratio. These results indicate that guarana supplementation influences the growth performance and carcass characteristics of finishing pigs, but does not improve the overall productive performance under the conditions evaluated.

The increasing demand for sustainable and cost-effective feed alternatives has stimulated the use of agro-industrial by-products in poultry nutrition. This study evaluated the effects of acid silage from pirarucu (Arapaima gigas) by-products (ASP), derived from fish-processing waste, on growth performance, physiological responses, and meat quality of slow-growing broilers. A total of 240 male Label Rouge broilers were assigned to diets containing 0, 1, 2, or 3% ASP from 8 to 56 days of age. Moderate ASP inclusion levels (1–2%) improved (p ≤ 0.05) growth performance by increasing weight gain and improving feed conversion ratio, particularly during the grower and finisher stages. Hematological analyses demonstrated favorable physiological responses, including increased (p ≤ 0.05) hemoglobin concentration, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin. Plasma biochemical parameters indicated improved (p ≤ 0.05) protein metabolism, with higher total protein, albumin, and globulin concentrations, while glucose, cholesterol, and urea remained unaffected (p > 0.05). Carcass evaluation revealed improved (p ≤ 0.05) breast yield at 2% ASP inclusion, and breast composition showed increased (p ≤ 0.05) protein, lipid, and mineral deposition, accompanied by reduced (p ≤ 0.05) moisture content. However, the highest inclusion level (3%) did not promote additional productive benefits. These findings demonstrate that moderate ASP inclusion (1–2%) can improve productive efficiency and meat nutritional quality while promoting sustainable reuse of aquaculture by-products, supporting circular and environmentally responsible poultry production systems.