Search Results (61)

Male Ross 308 finisher (19 to 33 days) broiler chickens (n = 672) were used to determine the standardized ileal digestible (SID) leucine (Leu)-to-lysine (Lys) ratio for the maximum growth performance and slaughter parameters. A basal diet (incl. wheat, triticale, soybean meal, sunflower meal, and synthetic amino acids) deficient in Leu was formulated, and supplementary L-Leu was used to achieve 0.9 and 1.25 SID Leu-to-Lys ratios in increments of 0.05. A slight deficiency in lysine was implemented to truly relate broiler performance to changes in the SID Leu-to-Lys ratio. Diets were fed to broilers in seven pens (12 broilers each). Eight birds per pen were used for carcass evaluation on day 33. Data analysis indicated that SID Leu-to-Lys ratios between 0.96 and 1.025 were required to achieve 95% and 98% of the maximum body weight gain, daily feed consumption, and the European production efficacy factor, respectively. The estimation of recommended SID Leu-to-Lys ratios for the feed conversion ratio and carcass parameters was not possible. Full article

A Capsicum spp.-based phytogenic solution (PHY) improved the performance and thermal tolerance of heat-stressed (HS) growing pigs. Two trials were conducted to further evaluate the HS pig response to supplemental PHY. Trial 1: The effects on the serum concentrations of amino acids (AAs) and the gene expression of tight junction proteins in the jejunum and ileum were assessed with 42 pigs (Landrace-Hampshire-Duroc; 27.0 ± 4.5 kg BW). There were three treatments (14 replicates): pigs under thermoneutral (TN) conditions fed control diet (TN-C); and HS pigs fed control diet without (HS-C) or with PHY (HS-PHY). Trial 2: Two-period digestion trial with eight ileal-cannulated pigs to analyze apparent ileal digestibility (AID) of AAs. Period 1: All TN pigs, fed the control (TN-C) or PHY-supplemented (TN-PHY) diet. Period 2: All HS pigs, fed the same diet as in period 1 (HS-C and HS-PHY). The control diet was based on wheat–soybean meal. In the jejunum, HS-C pigs had reduced occludin gene expression (p < 0.01) compared to TN-C pigs. HS-PHY pigs increased claudin-2 and tight-junction-protein-1 gene expression compared to HS-C (p < 0.05). In the ileum, HS-C and HS-PHY pigs had reduced occludin gene expression (p < 0.01). The serum concentrations of AAs decreased in HS-C compared to TN-C pigs (p < 0.05); except for arginine and isoleucine, HS-PHY pigs partially recovered serum AA levels. HS tended to reduce (p < 0.10; lysine and methionine) and reduced (p < 0.05) the AID of essential AAs. PHY did not mitigate the HS-associated reduced AA digestibility. In conclusion, these results support the concept that a phytogenic solution improves intestinal integrity and partially restores the post-absorption metabolism of amino acids, independent of the amino acid digestibility of heat-stressed pigs. Full article

This study examined the effects of replacing corn with an aged brown rice (ABR)–wheat mixture (ABR: wheat = 85%:15%) on laying performance, egg quality, yolk fatty acid profile, economic benefits, serum biochemistry, and nutrient digestibility in laying ducks. A 12-week trial with six hundred 32-week-old Jinding ducks were randomly divided into five groups, with 10 replicates per group, and each replicate contained 12 ducks. The levels of ABR–wheat mixture in the diet were 0%, 12.5%, 25%, 37.5%, and 50%, respectively, to replace equal amounts of corn. The basic diet of the control group was corn–soybean meal (corn accounted for 50%). The experimental period was 12 weeks (from 32 to 43 weeks old). No significant differences were observed in laying performances (p > 0.05). From a numerical perspective, the duck-housed laying rate and egg mass were highest in the 37.5% group and lowest in the 50% group. Yolk color declined linearly (p < 0.05) over 12 weeks. The albumen height and Haugh unit showed a quadratic increase in weeks 4 and 8 (p < 0.05). The relative content of monounsaturated fatty acids (MUFA) increased linearly (p < 0.05), while the relative content of polyunsaturated fatty acids (PUFA), ω-3 PUFA, ω-6 PUFA, and ω-6/ω-3 PUFA decreased linearly in egg yolks (p < 0.05). The triglycerides (TG) content in serum showed a significant secondary change (p < 0.05), with the 50% group significantly lower than the other treatment groups (p < 0.05). The apparent digestibility of ether extract (EE) in the diets decreased linearly (p < 0.05). The apparent digestibility of crude protein (CP) in the diets was significantly reduced with the 50% group (p < 0.05), while there was no significant difference between the 0% and 37.5% groups (p > 0.05). Compared with the control group, economic analysis revealed net gains of 0.04–0.10 USD/duck at ≤37.5% substitution, but a loss (−0.04 USD) at 50%. In conclusion, the ABR–wheat mixture could reduce the yolk color and yolk PUFA content, but it could improve albumen quality and increase yolk MUFA content. High-level ABR–wheat mixture (50%) significantly reduced the TG content in serum and nutrient digestibility of the diet and also showed a numerical decrease in laying rate and egg mass. Our findings suggest that up to a 37.5% ABR–wheat mixture can effectively replace corn in laying duck diets without negatively affecting laying performance, while improving albumen quality and altering yolk fatty acid composition. Full article

This study aimed to evaluate the effects of graded levels of red yeast rice residue (RYRR) on the growth performance, nutrient digestibility, and fecal microbiota of growing-finishing pigs. A total of 144 pigs were randomly allocated into four dietary treatment groups, over a 75-day experimental period. The study comprised a control group and three dietary supplementation groups receiving RYRR. The control (CON) group was fed a two-phase diet tailored to the pigs’ body weight, while the RYRR groups were provided with the CON diet, where corn, soybean meal, puffed soybeans, and wheat shorts were substituted with 5%, 10%, and 20% of RYRR. Supplementation with 10% RYRR enhanced the apparent digestibility of gross energy, dry matter, and crude fiber, while reducing the feed-to-gain ratio and serum triglyceride levels (p < 0.05). Microbiological analyses revealed that short-chain fatty acid-producing bacteria (Anaerotignum and Lachnospiraceae_UCG-009) were biomarkers in pigs fed the RYRR supplementation diets (p < 0.05). These results demonstrated that RYRR supplementation of the diet exerted beneficial effects on promoting nutrient digestibility as well as modulating the fecal microbiota of pigs, and the recommended proportion of RYRR added to the growing-finishing pigs’ diet is 10%. Full article

This floor pen study explored the effects of feeding mineral methionine hydroxyl analogue chelates (MMHACs) zinc (Zn), copper (Cu), and manganese (Mn) on growth performance, carcass processing weight and quality, nutrient digestibility, gizzard erosion score, and bone parameters of broilers. One-day-old Ross 308 male chicks (n = 384) were randomly allocated to four dietary treatments with eight replicate pens per treatment and 12 birds per pen. The treatments were as follows: (1) inorganic trace mineral ZnSO₄ 110 ppm, CuSO₄ 16 ppm, MnO 120 ppm (ITM); (2) MMHAC Zn 40 ppm, Cu 10 ppm, Mn 40 ppm (M10); (3) Inorganic trace mineral ZnSO₄ 110 ppm, tribasic copper chloride 125 ppm, MnO 120 ppm (T125); (4) MMHAC Zn 40 ppm, Cu 30 ppm, Mn 40 ppm (M30). The birds were fed nutritionally complete wheat sorghum soybean meal-based diets from days 0 to 42 with three feeding phases including starter (days 0–10), grower (days 10–21), and finisher (days 21–42). The findings revealed that birds on the T125, M10, and M30 groups possibly had higher feed intake (p = 0.052) and higher weight gain (p < 0.063) than birds on the ITM group from days 0 to 42. Furthermore, birds fed the M30 diet had higher thigh and drumstick weights compared to those fed the ITM diet at day 42 (p = 0.05). Additionally, birds offered the M30 diet had increased ileal Cu digestibility compared to birds offered the M10 and ITM diets at day 21 (p = 0.006). Gizzard erosion scores and bone parameters were similar between the dietary treatments. Hence, the supplementation of MMHACs to broiler diets at 30 ppm may be a more suitable strategy to increase weight gain and the thigh and drumstick processing weight while maintaining the bone health of broiler chickens. Full article

The high degradability of crude protein (CP) from fresh grass can impair its utilization in ruminants. The presence of a moderate level of polyphenolic substances in the diet of grazing animals could help to overcome this problem. The study aimed to evaluate the effects of supplementation with two varieties of faba bean, with different polyphenol contents, on milk yield and quality, as well as on grazing behaviour, in Cinisara grazing cows. A total of 30 cows, homogeneous per days in milk (61 ± 29) and milk yield (12.9 kg ± 3.2), fed on a mixed pasture (CP 17.9% DM) and supplied with grains (an equal mixture of barley, oats, and wheat) and mixed hay (CP 10.2% DM), were assigned to three dietary treatments and supplemented as follows: control group (C, 10 cows), 1 kg of hay, 6 kg of grains mixture, and 0.4 kg soybean meal; low polyphenols group (LP, 10 cows), 1 kg of hay, 4 kg of grains mixture, and 2 kg/d of faba bean var. Torrelama (total polyphenols 4.4 mg GAE/g DM; CP 28.4% DM); high polyphenols group (HP, 10 cows), 2 kg of hay, 4 kg of grains mixture, and 2 kg/d of faba bean var. Fanfare (total polyphenols 16.4 mg GAE/g DM; CP 28.9% DM). All groups were allowed to graze for 20 h/d on natural pasture forage. The HP supplement tended to increase the milk yield compared to that of the LP and C groups (17.1 vs. 15.3 and 14.6 kg/d, respectively; p = 0.057) but reduced the protein (3.20 vs. 3.39 and 3.47%; p = 0.009) and casein proportions (2.45 vs. 2.67 and 2.74%, respectively; p = 0.007) compared to those from the LP and C treatments. HP milk also showed a higher milk urea nitrogen (MUN) value compared to that of C milk, while an intermediate level was measured in LP milk (25.5 vs. 22.9 and 20.9 mg/dl, respectively; p = 0.036). No dietary effect was evident in the milk fatty acid profile. Eating time at pasture and biting rate were not affected by supplementation. The results do not seem to suggest a difference in the efficiency of use of supplements with different polyphenol contents. In any case, they seem to demonstrate that the use of faba beans, regardless of their polyphenol content, represents a valid alternative to soyabeans, also taking into account the tendency for an increased milk yield found by integrating pasture grazing with faba beans possessing a high level of polyphenols, without significant worsening of the qualitative characteristics of the milk or negatively affecting grazing behaviour. Full article

This study evaluated the trace mineral availability of zinc (Zn), copper (Cu), iron (Fe), manganese (Mn), and selenium (Se) in major feed ingredients, including corn, wheat, soybean meal (SBM), and fish meal (FM). Additionally, we assessed the bioavailability of these minerals in pigs supplemented with inorganic, organic, and nano-sized forms prepared via hot-melt extrusion (HME). A total of 64 barrows (Yorkshire × Landrace × Duroc crossbreds) with an average initial body weight of 26.61 ± 4.12 kg were housed individually in metabolic cages. Pigs were allocated to eight experimental diets in a completely randomized design, with eight replicates per diet group. The apparent total tract digestibility (ATTD) of Zn and Cu was significantly higher in SBM and FM than in the other ingredients (p < 0.05). SBM exhibited higher ATTD and standardized total tract digestibility (STTD) for Fe and Mn than corn, wheat, and FM (p < 0.05). Corn and wheat demonstrated significantly greater digestibility of Se than SBM and FM (p < 0.05). Supplementation with nano-sized minerals prepared by HME increased the digestibility of Zn and Cu, as well as their concentrations in pigs’ serum and liver, while reducing the fecal excretion of these minerals (p < 0.05). Organic mineral forms significantly enhanced Se bioavailability, improving its digestibility and concentrations in the liver and pancreas compared to the inorganic form (p < 0.05). In growth performance, organic and nano-sized mineral sources significantly improved growth rate without the increase in feed intake (p < 0.05). In conclusion, Zn and Cu from high-protein ingredients such as SBM and FM were more digestible than those from grains. Furthermore, plant-based ingredients, such as corn, wheat, and SBM, exhibited greater digestibility of Fe and Se. Among the trace mineral sources, the organic and HME-nano forms improved the bioavailability of Zn, Cu, and Se, while reducing their fecal excretion, thereby enhancing the efficiency of mineral utilization. Full article

To begin formulating broiler diets on a digestible calcium (Ca) basis, robust Ca digestibility values for ingredients and factors affecting this digestibility are needed. This study had three main objectives: (1) determine the standardized ileal digestibility (SID) of Ca and phosphorus (P) for seven plant-based feed ingredients in broilers, (2) assess the impact of phytate source on SID Ca from limestone (LS), and (3) evaluate the effect of phytase on SID Ca and P for the different ingredients. Two experiments were conducted to satisfy these objectives. In Experiment 1, a 4 × 2 × 2 factorial design was used, with four plant-based feed ingredients (corn, wheat, sorghum, and full-fat soybean meal (FFS)), two LS inclusions in the diet (absence of LS and the inclusion of LS required to achieve 0.65% Ca in the final diet), and two phytase doses (0 and 1000 FTU/kg diet). Experiment 2 utilized a 3 × 2 × 2 factorial design with three plant-based ingredients (soybean meal (SBM), rapeseed meal (RSM), and sunflower meal (SFM)), two LS inclusions in the diet (absence of LS and the inclusion of LS required to achieve 0.65% Ca in the final diet), and two phytase doses (0 and 1000 FTU/kg diet). The trial had eight replicate pens (6 broilers/replicate) per treatment. Data were analyzed using a factorial analysis in JMP Pro 16.0 with means separation performed when p < 0.05, using Tukey HSD. The SID Ca in the absence of phytase for wheat (72.9%) and FFS (69.9%) was higher (p < 0.05) than for sorghum (54.5%) and corn (46.3%). In Experiment 2, the SID Ca in the absence of phytase from SFM (61.0%) was higher (p < 0.01) than RSM (42.7%) and SBM (46.8%). The SID Ca from added LS was affected by the ingredient, with diets containing wheat and FFS resulting in the lowest (p < 0.05) SID Ca versus those containing corn and sorghum irrespective of phytase dose in Experiment 1, and the lowest (p < 0.05) for SBM and RSM vs. SFM in the absence of phytase in Experiment 2. Phytase supplementation increased (p < 0.01) SID Ca and SID P across all feed ingredients compared to non-supplemented diets. There was a two-way interaction (p < 0.01) of LS addition and ingredient on SID P in both experiments. The results of this study provide SID Ca and SID P values from the selected ingredients and show that phytate from different ingredients reacts differently with Ca from LS and should be considered when developing SID coefficients of Ca and P for use in commercial broiler feed formulation. The SID coefficients of Ca and P for the individual feed ingredients evaluated in this study will allow for the further development and transition towards dCa and dP in commercial feed formulation. Full article

Bread by-product and maize silage as substrates for Tenebrio molitor larvae were studied in four isonitrogenous diets: a control substrate (CTL) made of wheat grain, wheat bran, and soybean meal and three diets where wheat grain and wheat bran were partly substituted with bread by-product (BBP) or with this and either a low (MSL) or high (MSH) proportion of maize silage (170 or 310 g/kg, respectively). Larval weight was weekly monitored, and the chemical composition of larvae and residual substrates was analyzed at the end of the experiment. Larvae fed CTL and BBP grew more than those fed MSL and MSH (p < 0.001). Feed intake was greatest for BBP (p < 0.001), and consequently, feed-to-gain ratio (F:G) was better for larvae fed CTL than BBP, and better for BBP than MSL and MSH (p < 0.001). Besides, total production of crude protein and ether extract were greater for CTL and BBP than for MSH and MSL (p < 0.001). The inclusion of bread by-product in the substrate did not affect growth performance, whereas diets including maize silage impaired larval growth, substrate intake, and F:G. Both by-products can be advantageously used for feeding T. molitor larvae, but the impairments in growth performance should be considered to optimize production costs. Full article

Recent studies have discovered that wheat bran could stimulate digestive tract development, modulate intestinal microbiota, and improve the digestibility of fibrous ingredients in broilers. Wheat bran varies greatly in its chemical constituents. The objective of this study is to investigate how different types of wheat bran influence growth performance, nutrient digestion, and gut health in broiler chickens. Eight types of wheat bran were sampled and analyzed for nine constituents. A principal component analysis demonstrated that the wheat bran could be clustered into three groups based on the first principal component, namely low-fiber (LF), medium-fiber (MF), and high-fiber (HF) wheat bran. Wheat bran from the LF, MF, and HF groups significantly differed in terms of the contents of NDF, acid detergent fiber (ADF), hemicellulose, in vitro digestible energy (IVDE), crude fat, and ash (p < 0.05). A total of 324 seven-day-old broiler chicks were grouped into six body weight blocks. Each block of birds was randomly divided into six treatments, fed either a corn–soybean meal basal diet or five experimental diets, including 3% wheat bran from the LF, MF, and HF groups, until d 21. The feed/gain ratio was increased, and the coefficients of dry matter (DM, p = 0.001), gross energy (GE, p = 0.005) digestion, energy (p = 0.039), and CP (p = 0.051) retention were reduced in the birds that were fed 3% HF wheat bran. In contrast, in the birds fed 3% LF wheat bran, the coefficients of nutrient digestion and retention of energy and CP were not affected, but the CP (p = 0.009) and the NDF (p = 0.059) digestion ability were increased when switched to the same diet. In the cecal digesta, Barnesiella was enriched in the birds from the LF group, while Lachnospiracea was enriched in the birds from the MF group. Adding a moderate amount of wheat bran from the LF group could promote protein and fiber digestion and increase the abundance of Barnesiella in broilers. Full article

(1) Background: This study aimed to evaluate the effects of dietary xylanase addition on growth performance, nutrient digestibility, volatile fatty acids, and digesta viscosity at different digestive sites in weaned pigs fed wheat–soybean meal-based diets with reduced metabolizable energy. (2) Methods: A total of 312 weaned pigs (5.1 ± 0.9 kg, 20 ± 2 days of age) were assigned to one of six dietary treatments. The experimental diets were formulated in a three-phase nursery feeding program: phase 1 (d0–d7), phase 2 (d8–d21), and phase 3 (d22–d42). The experimental diets consisted of a wheat–soybean meal-based diet formulated to meet pig requirements (positive control, PC); the PC diet with a reduction of 100 kcal of metabolizable energy (ME) (negative control, NC); and the NC diet with either 900, 1800, 3600, or 7200 units of xylanase. Feed disappearance and body weight were measured at d7, 14, 21, and 42 in the nursery phase. The pen fecal score was assessed daily from d0 to d14 and three times a week from d15 to d28. On d21–d24 of the experiment (12 pigs per day), one pig per pen was selected for sample collection: ileal, cecal, and mid-colon digesta for viscosity and ileal digesta, feces for nutrient digestibility, and feces and cecal digesta for the measurement of volatile fatty acid. (3) Results: The addition of xylanase to the NC diets did not improve pig growth performance (body weight, feed conversion ratio, and average daily gain; p > 0.10) during the entire nursery phase. In Week 2 and Week 3, pigs fed xylanase had a lower (χ2 < 0.05) incidence of fecal scores 3 and 4 (diarrhea) than the PC and NC diets. In addition, the apparent total tract digestibility of neutral detergent fiber and acid detergent fiber increased linearly (p < 0.1) in response to xylanase addition. Xylanase addition (900 to 7200 U) decreased digesta viscosity in the colon compared to the PC and NC diets. Furthermore, xylanase addition resulted in a lower (p < 0.05) concentration of acetic, propionic, butyric, valeric, and total volatile fatty acid in cecal samples compared to PC. The addition of xylanase resulted in greater acetic and valeric acid concentrations in cecal samples compared to the NC group (p < 0.10). (4) Conclusions: Xylanase addition can improve nutrient digestibility, particularly at the total tract level, and reduce viscosity in the hindgut, which could be related to decreasing the occurrence of looseness. However, its impact on growth performance was minimal in wheat–soybean meal-based diets with a reduction of 100 kcal of ME. Full article

The objective of this work was to ascertain the nutritive value of six concentrate feedstuffs commonly used in guinea pig feed manufacturing through the substitution method. Six test diets were obtained by replacing the corresponding basal mixture with 40% corn, 50% barley, 45% wheat bran, 35% soybean meal, 30% pigeon pea, or 30% Leucaena leaf meal. Sixty-three guinea pigs were randomly assigned to one of the nine experimental diets (three basal diets and six test diets, with seven animals per diet). The animals were housed in individual cages and provided with feed and water ad libitum. Following a ten-day adaptation period, the feed intake and faeces excretion were monitored for a further five days. The digestible energy content, expressed as kcal/kg dry matter (±standard error), was 3857 ± 83 for corn, 3454 ± 68 for barley, 2911 ± 110 for wheat bran, 3855 ± 81 for soybean meal, 3105 ± 79 for pigeon pea, and 2972 ± 72 for Leucaena leaf meal. The apparent total tract digestibility of crude protein, expressed as % (±standard error) was 73.8 ± 4.9 for corn, 69.5 ± 4.6 for barley, 76.4 ± 3.6 for wheat bran, 88.4 ± 1.0 for soybean meal, 62.1 ± 1.9 for pigeon pea, and 68.0 ± 1.8 for Leucaena leaf meal. Further research is required to increase knowledge about these and other feedstuffs for guinea pigs. Full article

With the continuous optimization of feed ingredients in livestock production, barley has garnered significant attention as a potential substitute for corn in feed. This study aims to investigate the effects of replacing part of the corn and soybean meal with barley, wheat bran, and rapeseed meal on Wenshan cattle, focusing on the rumen microbial community, blood physiological and biochemical indicators, and growth traits. Through an intensive feeding experiment with two different dietary ratios, we found that adding barley to the diet significantly reduced the host’s blood lipid concentration and significantly increased the height, body length, heart girth, and average daily weight gain of Wenshan cattle. Analysis of the rumen microbial community structure showed that the addition of barley significantly affected the relative abundance of Firmicutes, Proteobacteria, and Bacteroidetes, with the relative abundance of Spirochaetes being significantly lower than that of the control group (p < 0.05). The dominant bacterial groups mainly included Acinetobacter, Solibacillus, and Lysinibacillus. In summary, this study reveals the potential of different feed ingredient ratios involving barley, wheat bran, and rapeseed meal in the production performance of Wenshan cattle. By regulating blood physiology and improving the rumen micro-ecological structure, it provides new scientific evidence for optimizing livestock and poultry feeding management strategies. Future research will further explore the optimal application ratio of barley under different feeding conditions and its long-term impact on animal health and production performance. Full article

The objectives of this study were (1) to determine the net energy requirements for the maintenance of gestating sows based on indirect calorimetry, and (2) to explore the feasibility of predicting the net energy requirements for the maintenance of gestating sows based on daily heart rate monitoring. In Exp. 1, six Landrace × Yorkshire crossbred reproductive sows with an initial body weight of 229.5 ± 14.9 kg at d 56 of gestation were randomly assigned to six diverse energy feeding levels using a 6 × 6 Latin square design. The experimental diet was formulated using corn, soybean meal, and wheat bran as major ingredients, and the six feeding levels were set as 1.2, 1.4, 1.6, 1.8, 2.0, and 2.2 times metabolizable energy for maintenance (100 kcal ME/kg BW^0.75·d⁻¹), respectively. The animal trial lasted for six periods with 9 days per period, encompassing 5 days of adaptation, 3 days of calorimetry in fed state, and 1 day of calorimetry in fasting state. In Exp. 2, six Landrace × Yorkshire crossbred pregnant sows with an initial body weight of 232.5 ± 12.5 kg at d 64 were fed a corn–soybean meal diet. All sows were tested in a respiratory calorimetry chamber for a 4 day calorimetry test. The heat production of the gestation sows was measured every 5 min using indirect calorimetry, and the heart rate of the gestating sows was recorded every minute using a belt-shape monitor. The results showed that the net energy requirements for the maintenance of gestating sows significant increased as the gestational stage progressed (p < 0.05), and a linear regression model revealed the average net energy requirement for the maintenance of gestating sows was 410 kJ/BW^0.75 d⁻¹ during late gestation (days 70–110). Moreover, the average heart rate of the gestating sows was 84 bpm, and the mathematical model developed to predict the net energy requirements for the maintenance of gestating sows was ${NE}_m(\mathrm{k}\mathrm{c}\mathrm{a}\mathrm{l}/\mathrm{h})={\displaystyle \frac{1990}{1+\mathrm{e}\mathrm{x}\mathrm{p}\left[\frac{136-HR\left(\mathrm{b}\mathrm{p}\mathrm{m}\right)}{43}\right]}}$. In conclusion, the average net energy requirement for the maintenance of sows during late gestation was 410 kJ/BW^0.75 d⁻¹, and the utilization of the heart rate monitoring method was found to provide a relevant, accurate prediction for the net energy requirements of sows. Full article

The present study investigated the effect of supplementing a multi-carbohydrase enzyme complex (MCE) in corn–soy-based diets of Pekin ducks. The treatments were as follows: positive control (PC, 2980 and 3120 kcal/kg for starter and grower, respectively); negative control (NC, −132 kcal/kg energy reduction to PC achieved by reduction of fat and wheat middlings as filler); NC + MCE at 75 ppm (E75); 100 ppm (E100); and 125 ppm (E125) randomly distributed in 10 replicate pens with 25 birds each. Performance was evaluated after 14 and 35 d. On day 36 of the trial, five ducks/pen were processed to evaluate carcass traits. During days 1–14, the PC had a lower (p < 0.01) feed intake compared to all other treatments. At 14 and 35 d of age the NC decreased (p < 0.001) the body weight (BW) of the ducks compared to the PC by −8.3% and −5.3%, respectively. The NC BW was lower (p < 0.001) compared to all MCE-supplemented treatments at 14 and 35 d. The BW of E75, E100, and E125 treatments was not different (p > 0.05) from the PC at both evaluation periods. Cumulatively (1–35 d), the NC resulted in a weight-adjusted FCR increase (p = 0.001) of 9.9% compared to the PC, and the FCR of E75, E100, and E125 were able to recover 72.3%, 66.4%, and 63.5%, respectively, compared to the PC. The carcass and breast weights were lower (p < 0.001) in the NC compared to all other treatments, and no differences (p > 0.05) were observed between the MCE-supplemented treatments and the PC. In conclusion, these results suggest that the MCE supplementation can maintain duck growth performance with no negative effects on carcass traits in energy-reduced corn–soybean meal-based diets. From the results of the trial, 75 ppm MCE delivered the best performance recovery and 125 ppm MCE supplementation had the best % breast yield. Full article