Prosopis juliflora piperidine alkaloid extract levels in diet for sheep change energy and nitrogen metabolism and affect enteric methane yield.

BACKGROUND: Ionophore antibiotics improve the efficiency of energy metabolism, which has driven their use as a feed additive in ruminants for decades. Currently, they have not been approved in many countries, generating a challenge for the immediate search for plant extracts with a similar mode of action on rumen metabolism. This study evaluated the effects of enriched Prosopis juliflora (mesquite) piperidine alkaloid extract (MPA) levels as an alternative phytoadditive to sodium monensin (MON) in sheep. RESULTS: The MPA diet did not differ from MON with regard to nutrient intake. A quadratic effect (P < 0.05) was observed for organic matter and neutral detergent fibre digestibility, with respective maximum point at 25.40 and minimum point at 0.95 mg kg-1 MPA. The MPA levels linearly decreased (P < 0.05) faecal nitrogen loss. MPA did not differ from MON with regard to nutrient digestibility, and MPA levels increased (P < 0.05) the proportion of digestible energy and metabolizability from dietary gross energy. The MPA levels linearly decreased (P < 0.05) enteric CH4 production, the yield showing lower (P < 0.05) energy loss as CH4 than MON. CONCLUSION: The results show that MPA levels of 17.3 and 27.8 mg kg-1 are enteric CH4 inhibitors and enhance energy and protein utilization, indicating a promising alternative to MON for ruminants. © 2022 Society of Chemical Industry.

Nitrogen metabolism in lambs fed diets containing peach palm meal.

The objective of this study was to evaluate the nitrogen metabolism of lambs fed diets containing peach palm meal substituting maize (0, 10, 40, 60, and 85 % DM). Thirty Santa Inês uncastrated lambs with an average initial body weight of 21.6 ± 0.87 kg were distributed in a completely randomized design with five diets and six replicates. The nitrogen (N) intake (g/day, %BW) and the fecal N decreased linearly as the peach palm meal was added to the concentrate. The urinary N, however, responded quadratically, with maxima at the level of 29.97 and 40.44 % of substitution of maize for peach palm meal when expressed in g/day and %BW, respectively. The substitution of maize for peach palm meal reduced the retention of nitrogen and the microbial protein synthesis in the lambs.

Intake, digestibility and performance of lambs fed diets containing peach palm meal.

The aim of this study was to evaluate the intake and apparent digestibility of nutrients, performance, and plasma glucose concentration of ram lambs fed diets containing peach palm meal substituting maize (0, 10, 40, 60, and 85 % dry matter (DM)). Thirty Santa Inês rams with an average initial body weight of 21.6 ± 0.87 kg were distributed in a completely randomized design with five diets and six replicates. The substitution of the maize for the peach palm meal affected (P < 0.05) the intakes of DM, organic matter (OM), crude protein (CP), neutral detergent fiber corrected for ash and protein (NDFap), total carbohydrates (TC), total digestible nutrients (TDN), and metabolizable energy (ME), which decreased linearly (P < 0.05); the intake of ether extract (EE), however, fit an increasing linear equation (P < 0.05). The apparent digestibility coefficients of DM, OM, NDFap, and TC decreased linearly (P < 0.05) as the level of peach palm meal in the concentrate was increased. The total weight gain and the average daily gain decreased by 0.09 and 0.001 kg with each level of substitution of the maize for peach palm meal, respectively. It is recommended to substitute 40 % of the maize for peach palm meal.