Intake, digestibility, ingestive behavior, and nitrogen balance of goats fed with diets containing residue from tamarind fruit

Fatty acid profile, physicochemical composition and carcass traits of young Nellore bulls fed Acacia mearnsii extract

Fatty acid profile, physicochemical composition, and carcass traits of 32 young Nellore bulls were assessed following the supplementation of Acacia mearnsii extract at levels of 0, 10, 30, and 50 g/kg of total dry matter (DM) in a completely randomized experiment with four treatments and eight replicates. Adding 50 g/kg DM of condensed tannins (CT) from Acacia mearnsii in the bulls' diet reduced DM intake, average daily gain, and meat lipid oxidation (P ≤ 0.05). The pH, centesimal composition, collagen, and meat color indexes of the longissimus muscle were not altered by the addition of Acacia mearnsii (P > 0.05). Cooling loss increased (P = 0.049) linearly. Including Acacia mearnsii in diet reduced the Warner-Bratzler shear force (WBSF, P = 0.018) of longissimus muscle of the bulls. The concentration of C16:0, C17:0, C24:0, t9,10,11,16-18:1, c9t11-18:2, C18:2n-6, C20:4n-6, 20:5n-3, 22:5n-3, and 22:6n-3 in the muscle increased due to the addition of Acacia in the diet (P ≤ 0.05), with the highest muscle concentrations caused by the addition of 10 to 30 g Acacia. c9-18:1 and t16-18:1 reduced linearly. ƩSFA, ƩBI, Ʃcis- and ƩMUFA, Ʃn-3, Ʃn-6, and ƩPUFA (P ≤ 0.05) quadratically increased at higher concentrations of addition of Acacia, above 30 g/kg DM. It is recommended to include Acacia mearnsii extract up to 30 g/kg total DM in diets for young bulls as it improves CLA, PUFA and TI and reduces lipid oxidation. Acacia mearnsii extract as source of CT at 50 g/kg DM negatively impacted the young bulls performance.

Nutrient intake, digestibility, feeding behavior, nitrogen balance, and performance of feedlot goat kids fed high-concentrate diets containing licury cake (Syagrus coronata)

The current trial was carried out to evaluate the impacts of adding licury cake (Syagrus coronata) in high-concentrate diets for goat kids feedlot-finished on growth performance and metabolic parameters. Forty crossbred non-castrated Boer goat kids with approximately four months and similar initial live weights (20.15 ± 2.79 kg). The experimental design used in this study was a completely randomized, with four diets (0, 10, 20, and 30% of licury cake inclusion in a dry matter basis (DM)). Licury cake inclusion decreased nutrient intake and digestibility (P < 0.05). Times spent in feeding (P < 0.001) and rumination (P = 0.003) activities, number of events in feeding (P < 0.001) and idling (P = 0.015) increased, whereas a linear reduction occurred in feeding and rumination efficiencies of DM and neutral detergent fiber (P < 0.001). Nitrogen (N) intake, retained N (P < 0.001), triglycerides concentrations (P = 0.002), aspartate-aminotransferase, alanine-aminotransferase, and gamma-glutamyltransferase decreased with the licury cake inclusion (P < 0.05). Final body weight (P = 0.008), average daily gain (P = 0.001), and total weight gain (P = 0.001) decreased linearly when licury cake was included in diets. High-concentrate diets containing increasing levels of licury cake decrease intake and apparent digestibility of nutrients and performance when supplied for goat kids feedlot-finished. Therefore, the inclusion of the studied levels of licury cake in goat kids fed high-concentrate diets is not recommended for feedlot-finished systems.

Tannins from Mimosa tenuiflora in the diet improves nutrient utilisation, animal performance, carcass traits and commercial cuts of lambs

Context Tannins are polyphenolic compounds found in legumes, trees and forage shrubs, such as Mimosa tenuiflora, and form hydrogen bonds with proteins. Aims The objective of the present study was to determine the optimal dietary concentration of natural tannins from M. tenuiflora for enhancing intake, digestibility, nitrogen (N) and tannin physiological balance, performance, carcass traits and commercial cuts of lambs. Methods Forty-eight uncastrated Santa Ines lambs were distributed between two experiments, each with four diets containing natural tannins (1.21 (control), 9.29, 17.4 and 25.4 g/kg dry matter (DM) total) from M. tenuiflora hay. Key results With increasing level of inclusion of natural tannins from M. tenuiflora hay in the diet, there were quadratic increases (P ≤ 0.05; up to 17.4 g/kg DM inclusion) in the daily nutrient intake, N faecal excretion, N urinary excretion, performance, carcass traits and rib and loin commercial cut weights of lambs. However, intake, faecal excretion, physiological balance of tannins and carcass leg circumference increased (P ≤ 0.05) linearly with an increasing inclusion of tannins from M. tenuiflora hay. Furthermore, there were linear decreases (P ≤ 0.05) in the digestibility of DM, crude protein, neutral detergent fibre corrected for ash and protein, acid detergent fibre, non-fibrous carbohydrate and total digestible nutrients and decreases in faecal excretion of total phenolic compounds and feeding efficiency in lambs with increasing dietary concentration of tannins. Conclusions It is recommended that M. tenuiflora hay replace Brachiaria decumbens hay at 250 g/kg of dietary roughage, corresponding to 17.4 g/kg DM of tannins, in the diet of Santa Ines finishing lambs because the resulting increased bioavailability of tannins improves nutrient intake, N retention, average daily gain, carcass weight and the weights of the most profitable cuts (leg, loin and rib). Implications The use of M. tenuiflora legume (which is common in the Caatinga biome) as hay roughage in the lamb diet increases tannin bioavailability and the efficiency of protein use, consequently improving performance and contributing to the economic viability of sheep production in the region.