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A data set of individual observations was compiled from digestibility trials to examine the relationship between the duodenal purine bases (PB) flow and urinary purine derivatives (PD) excretion and the validity of different equations for estimating rumen microbial N (Nm) supply based on urinary PD in comparison with estimates based on duodenal PB. Trials (8 trials, n= 185) were conducted with male sheep fitted with a duodenal T-type cannula, housed in metabolic cages, and fed forage alone or with supplements. The amount of PD excreted in urine was linearly related to the amount of PB flowing to the duodenum (P< 0.05). The intercept of the linear regression was 0.180 mmol/(d·kg0.75), representing the endogenous excretion of PD, and the slope was lower than 1 (P< 0.05), indicating that only 0.43% of the PB in the duodenum was excreted as PD in urine. The Nm supply estimated by either approach was linearly related (P< 0.05) to the digestible OM intake. However, the Nm supply estimated through either of 3 published PD-based equations probably underestimated the Nm supply in sheep.

A study was conducted to determine the ileal digestible energy (IDE), ME, and MEncontents of bakery meal using the regression method and to evaluate whether the energy values are age-dependent in broiler chickens from zero to 21 d post hatching. Seven hundred and eighty male Ross 708 chicks were fed 3 experimental diets in which bakery meal was incorporated into a corn-soybean meal-based reference diet at zero, 100, or 200 g/kg by replacing the energy-yielding ingredients. A 3 × 3 factorial arrangement of 3 ages (1, 2, or 3 wk) and 3 dietary bakery meal levels were used. Birds were fed the same experimental diets in these 3 evaluated ages. Birds were grouped by weight into 10 replicates per treatment in a randomized complete block design. Apparent ileal digestibility and total tract retention of DM, N, and energy were calculated. Expression of mucin (MUC2), sodium-dependent phosphate transporter (NaPi-IIb), solute carrier family 7 (cationic amino acid transporter, Y+system, SLC7A2), glucose (GLUT2), and sodium-glucose linked transporter (SGLT1) genes were measured at each age in the jejunum by real-time PCR. Addition of bakery meal to the reference diet resulted in a linear decrease in retention of DM, N, and energy, and a quadratic reduction (P< 0.05) in N retention and ME. There was a linear increase in DM, N, and energy as birds’ ages increased from 1 to 3 wk. Dietary bakery meal did not affect jejunal gene expression. Expression of genes encoding MUC2, NaPi-IIb, and SLC7A2 linearly increased (P< 0.05) with age. Regression-derived MEnof bakery meal linearly increased (P< 0.05) as the age of birds increased, with values of 2,710, 2,820, and 2,923 kcal/kg DM for 1, 2, and 3 wk, respectively. Based on these results, utilization of energy and nitrogen in the basal diet decreased when bakery meal was included and increased with age of broiler chickens.

Quillaja saponariaand Yucca schidigeraare plants rich in saponins, which present surfactant or detergent properties with molecules containing fat-soluble nucleus and either a steroid or triterpenoid structure. Quillaja and yucca biomass also contain polyphenols, which possess antioxidant, antimicrobial, and anti-inflammatory properties. Plant-based feed additives have been increasingly used in poultry feeds; therefore, this study was conducted to evaluate the effects of an additive containing polyphenols and saponins of a proprietary blend from Q. saponariaand Y. schidigera(QY) biomass on growth performance and carcass yield as well as on nutrient digestibility, blood biochemistry and intestinal measurements of broilers. Broilers were fed a nonsupplemented control diet (Control); Control supplemented with a commercial additive from QY (250 g/ton) from d 1 to 42; Control + QY from d 28 to 42, and Control + QY from d 35 to 42. There were no effects of dietary treatments on BW gain, feed intake, carcass yield, and blood biochemistry parameters; however, from d 1 to 42, birds fed QY during the overall period had lower FCR compared to the Control. Intestinal permeability was reduced with QY, whereas higher ileal digestibility of DM, nitrogen and energy as well as higher villus height and lower crypt depth were obtained when broilers were fed QY from d 28 to 42. In conclusion, the quillaja and yucca biomass additive improved jejunal morphometric, intestinal permeability and nutrient digestibility of broilers, and these effects were associated with the improved FCR. The additive demonstrated satisfactory results on nutrient digestibility and villus height when supplemented in grower and finisher diets for broilers.

Two experiments (Exp.) were conducted to evaluate the effects of exogenous carbohydrases on nutrient and energy utilization of corn with different compositions by broilers. In Exp. 1, a total of 448 Cobb 500 male chicks were distributed in a 2 × 4 factorial arrangement (corn from regions geographically located in the North or South of Brazil x 4 carbohydrases supplementation), with 8 replicate cages of 7 birds each. In Exp. 2, 672 Cobb 500 male chicks were fed 12 experimental feeds, in a 3 × 4 factorial arrangement [3 corn endosperm compositions (waxy, semi-dent, or semi-flint) x 4 carbohydrases], with 8 replicate cages of 7 birds. Birds were fed semi-purified test diets with 95.9% corn from d 14 to 24 in both studies. In Exp. 1, α-amylase, β-xylanase, or carbohydrase complex (cellulase, glucanase, and xylanase) were added to the diet. In Exp. 2, α-amylase, β-xylanase, or α-amylase + β-xylanase were supplemented. Digestibility of DM, N, ether extract (EE), Ca, and P as well as AME, AMEn, and IDE were determined. In Exp. 2, jejunal starch digestibility was determined on d 24. Data were subjected to analysis of variance and means were compared by Tukey test (P≤ 0.05). Corn from the North origin had higher AME, AMEn, and digestibility of DM and N compared to the South (P≤ 0.05). Amylase supplementation led to increases of 3% in AME and 2% in N digestibility when compared to the non-supplemented feeds (P≤ 0.01). In Exp. 2, the highest ME values and EE digestibility were observed in the semi-flint corn compared to the waxy, whereas the semi-dent presented the highest digestibility of N and starch. Corn diets supplemented with amylase + xylanase had improvements of 2.5% AMEnand 3% starch digestibility. In conclusion, energy and nutrient utilization of corn by broilers depend on the region where it was grown. Corn genetics, expressed by the endosperm composition, and carbohydrase supplementation influenced energy and nutrient utilization by broilers.

Two experiments (Exp.)were conducted to evaluate effects of a lysophospholipid-based bio-emulsifier (LPL)on growth performance, nutrient digestibility and energy utilization of broilers as well as the return on investment (ROI). In Exp. 1, 392 chicks were housed in battery cages in a completely randomized design with 8 treatments and 7 replicates of 7 birds each from d 0 to 21 posthatch. In Exp. 2, 1,400 chicks were allocated in floor pens and fed the same 8 treatments, with 7 replicates and 25 birds each from d 0 to 43 posthatch. Treatments consisted of 6 degummed soybean oil-based diets: positive control (PC1); PC1 formulated with 500 g/ton LPL (PC1+LPL on top); PC1 formulated with 60 kcal LPL matrix (PC1+LPL60); PC1 formulated with 100 kcal LPL matrix (PC1+LPL100); and two negative controls NC-60 and NC-100 with reductions of 60 and 100 kcal/kg ME, respectively. Two other diets were formulated with acid soybean oil: positive control (PC2)and PC2 formulated with 60 kcal LPL matrix (PC2+LPL60). In Exp. 1, performance was evaluated from d 0 to 21, ME and ileal digestibility of DM, CP and energy were determined on d 21. In Exp. 2, growth performance was evaluated from d 0 to 42, and on d 43 carcass and abdominal fat yields were calculated. There were no effects of soybean oil sources in any parameter. Inclusion of LPL increased (P < 0.05) BW gain and ileal digestibility of DM, fat and CP. Broilers fed the PC1+LPL on top diet had increased (P < 0.05) performance, ileal digestibility and energy utilization as well as decreased abdominal fat compared to NC-60 or NC-100. The use of LPL on top had a ROI of 8:1 vs. PC1, considering the gains in revenue of the slaughtered broilers in relation to the investment with LPL in feed. In conclusion, a lysophospholipid-based bio-emulsifier increased performance, digestibility and return on investment of broilers fed standard or reformulated diets.

Wooden breast (WB) myopathy was investigated in broilers fed varying energy and protein at early ages. Correlation analyses were conducted between echogenicity of ultrasound images (US) of breast muscle from live birds and WB after slaughter. A total of 1,000 Cobb 500 one-day-old male chicks were fed on five dietary programs with eight replicates of 25 birds each, in a completely randomized design. Control feeds (commercially used ME and ideally balanced amino acids) or low-density feeds (low EP, with reductions of 50 kcal/kg ME and 0.20% dig. Lys compared to the control) were formulated. Feeds were provided in different periods: 1 to 7 d, 8 to 14 d, 15 to 21 d or 22 to 28 d. All broilers were fed a common basal diet thereafter until 49 d. Images using US were obtained once a week from all individuals and WB scored from one slaughtered bird per replication (0, normal; 1, mild hardening in the upper breast muscle; 2; moderate hardening in the upper and/or lower breast muscle; 3, severe hardening; 4, severe hardening with hemorrhagic lesions and yellow fluid). Blood was collected for enzyme investigation from the weekly slaughtered bird. Broilers had lower BWG and higher FCR when fed low EP feeds, regardless of the period fed when compared to the control (P< 0.001). Growth compensation, however, occurred afterwards such that all birds presented similar performance at the end. At 14, 21, and 28 d, broilers previously fed low EP feeds had lower WB scores (P< 0.001) compared to birds fed the control; however, both groups presented increased WB scores after 28 d. Wooden breast was positively correlated with breast echogenicity at 21 d (r = 0.31), 28 d (r = 0.43), 35 d (r = 0.21) and 42 d (r = 0.39). In conclusion, dietary energy and protein affected the development of WB scores in broilers and breast US images can be used as an early predictor of WB.