Negative Control Diet Research Articles

Effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase on growth performance, meat quality, intestinal measurements, and nutrient utilization in broiler chickens.

The current study aimed to investigate the effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase in high non-starch polysaccharides (NSP) diets with low energy on growth performance, meat quality, intestinal measurements, stress responses, and energy and nutrient utilization in broiler chickens. A total of four hundred 8-d-old Ross 308 broiler chickens were randomly allotted to 1 of 4 treatment groups with 10 replicates. A positive control (PC) diet was formulated with adequate energy and nutrients, whereas a negative control (NC) diet had 100 kcal/kg less AMEn than the PC diet with increasing inclusion of high NSP ingredients. Two additional diets were produced by supplementing 0.1% xylanase alone or 0.1% xylanase and β-glucanase mixture in the NC diet. Experiments lasted for 27 d. Birds fed PC diets had less (p<0.05) FCR than those fed NC diets. Birds fed NC diets supplemented with xylanase alone or combination of xylanase and β-glucanase had less (p<0.05) FCR than those fed NC diets. Dietary supplementation of xylanase alone in NC diets exhibited the highest (p<0.05) breast meat pH among dietary treatments. Birds fed PC diets or NC diets supplemented with xylanase and β-glucanase combination exhibited greater (p<0.05) VH:CD ratio than those fed NC diets. Dietary supplementation of xylanase alone and combination of xylanase and β-glucanase in NC diets decreased (p<0.05) ileal digesta viscosity and increased (p<0.05) xylo-oligosaccharide concentrations in the gastrointestinal tract (GIT) compared with NC diets without affecting energy and nutrient utilization in NC diets. Dietary supplementation of xylanase in high NSP diets with low energy concentrations improves growth performance by decreasing digesta viscosity and increasing concentrations of xylo-oligosaccharides in the GIT of broiler chickens. However, little additional benefits of β-glucanase supplementation in combination with xylanase are identified for broiler chickens.

Dietary superdosing of phytase positively affects growth, mineral utilization and amino acid availability of channel catfish (Ictalurus punctatus)

The present study investigated the effects of supplementing high levels (superdosing) of dietary phytase on growth performance, mineral utilization and digestibility of amino acids in different regions of the gastrointestinal (GI) tract of fingerling channel catfish. The negative control (NC) diet was formulated with primarily soybean meal as a protein feedstuff which contributed 0.61 % total phosphorus (P) but was deficient in available P at 0.11 % of diet. Five other diets were formulated either with supplemental monocalcium phosphate at 1 % of diet in the positive control (PC), or supplemented with Quantum Blue phytase (AB Vista, Plantation, Florida) at 1000, 2000, 4000, or 8000 phytase units (FTU)/kg of diet. Groups of 20 catfish were each stocked into 24 aquaria operated as a closed, recirculating system with biological and mechanical filtration. All dietary treatments were assigned randomly to quadruplicate aquaria and initially fed at 6 % of total body weight per day. Feed quantities were adjusted weekly after weighing all fish in each aquarium as a group, and feeding levels were maintained close to apparent satiation throughout the 8-week feeding trial. Phytase supplementation significantly (P < 0.05) increased various responses of channel catfish including weight gain, feed efficiency, and protein retention compared to catfish fed the NC diet, resulting in values that were similar to catfish fed the PC diet. Moreover, catfish fed the phytase-supplemented diets had higher bone ash, calcium (Ca), magnesium (Mg), P, manganese (Mn), and zinc (Zn), as well as retention of Ca, Mg, P, iron (Fe), Mn, and Zn in whole-body tissues. Additionally, apparent availability of P from the posterior intestinal region increased with dietary phytase supplementation, with reduced excretion of nitrogen, Ca, Mg, P, copper (Cu), Mn, and Zn observed in comparison to fish fed the NC diet. Apparent digestibility coefficients for many of the indispensable and dispensable amino acids were increased by phytase supplementation, except for histidine, methionine, threonine, and taurine. This improvement in amino acid availability occurred only in the posterior region of the gastrointestinal tract. Channel catfish fed the diet containing 4000 FTU/kg diet had the highest postprandial plasma phosphorus level most of the time, except at 24 h after feeding. Based on these various responses, the optimal dietary phytase dosage was determined to average 5492 FTU/kg diet.

Effect of increasing supplementation of dietary glycine on growth performance, meat quality, liver characteristics, and intestinal health in broiler chickens raised under heat stress conditions

The current study aimed to investigate the effect of increasing supplementation of dietary glycine (Gly) on growth performance, meat quality, liver characteristics, and intestinal health in broiler chickens raised under heat stress (HS) conditions. A total of one thousand six hundred 25-d-old broiler chickens were randomly allotted to 1 of 5 dietary treatments with 8 replicates. Each replicate comprised 20 male and 20 female birds. A negative control (NC) diet was prepared to meet or exceed energy and nutrient requirement estimates, whereas a positive control (PC) diet was formulated to contain increasing concentrations of AMEn by 50 kcal/kg as well as those of digestible amino acids, total Ca, and available P by 10% compared with the respective concentrations in the NC diet. Three additional diets were prepared by supplementing the NC diet with 0.4, 0.8, or 1.6% Gly. All chickens were raised under cyclic HS conditions at 29°C ± 0.89°C for 10 h/d and 23°C ± 1.45°C for the remaining time over an 18-d feeding trial. Results indicated that broiler chickens fed the NC diet had a greater (P < 0.05) FCR than those fed the PC diet under HS conditions. Increasing supplementation of up to 1.6% Gly in diets decreased (linear, P < 0.001) FCR in broiler chickens. Increasing supplementation of dietary Gly tended to increase (linear, P = 0.070) water holding capacity in the breast meat. Increasing supplementation of dietary Gly decreased (linear, P < 0.05) serum aspartate aminotransferase concentrations and tended to decrease blood heterophil:lymphocyte (linear, P = 0.083) and liver malondialdehyde concentrations (quadratic, P = 0.084). A tendency for increased villus height (linear, P = 0.086) and a significant increase in villus height:crypt depth ratio and goblet cell numbers (linear, P < 0.05) were identified following increasing Gly supplementation. In conclusion, increasing supplementation of dietary Gly improved feed efficiency, meat quality, liver health, and intestinal morphology possibly by mitigating oxidative stress and stress response in broiler chickens raised under HS conditions.

Synergistic Effects of Hydroxychloride and Organic Zinc on Performance, Carcass Characteristics, Liver and Tibia Mineral Profiles of Broiler Chickens

AbstractThis study investigated the potential synergism between hydroxychloride and organic zinc (Zn) at different levels on performance and carcass characteristics of broiler chickens. There were seven experimental diets including a negative control diet without any supplemental Zn, and six diets with 80 mg/kg added Zn in the forms of ZnSO4, hydroxychloride Zn (HCZ) and organic Zn (ORZ), and a combination of HCZ and ORZ at 40 mg/kg HCZ + 40 mg/kg ORZ (HCZ40-ORZ40), 55 mg/kg HCZ + 25 mg/kg ORZ (HCZ55-ORZ25), and 70 mg/kg HCZ + 10 mg/kg ORZ (HCZ70-ORZ10). Each diet was replicated eight times with 17 chicks per replicate. On day 35, HCZ70-ORZ10 and HCZ40-ORZ40 diets resulted in the highest body weights (P &lt; 0.05). Throughout the entire production period (1–35 days), all HCZ and ORZ diets significantly improved feed conversion ratio (FCR) compared to PC (P &lt; 0.05), with HCZ40-ORZ40 showing the lowest FCR. Breast meat yield was lower in NC-fed birds, while HCZ80 and HCZ70-ORZ10 groups had the lowest abdominal fat weight (P &lt; 0.05). Liver and gizzard weight, tibia breaking strength, and ash percentage, footpad dermatitis, and hock burns were not affected. Tibia Zn content was higher in HCZ or ORZ-supplemented birds compared to NC (P &lt; 0.05), whereas other minerals in tibia and liver were unaffected. In summary, the absence of supplemental Zn negatively affects growth and carcass characteristics, whereas replacing ZnSO4 with HCZ, ORZ, or their combinations improves bodyweight and FCR. HCZ70-ORZ10 and HCZ40-ORZ40 were identified as optimal combinations for maximizing feed efficiency.

PSI-25 Improvements in the jejunal villus morphometry and increases in the number of goblet cells with the addition of humic substances from vermicompost in weaned pigs

Abstract An experiment was carried out with the objective of evaluating the effects of the addition of humic substances (HS) from vermicompost in the feed on the histology measurements and number of goblet cells in the jejunal villus in piglets at weaning. Piglets (n = 200) were housed in groups of five in elevated pens and were assigned to one of four treatments: 1 = Positive control diet (PC) with antibiotic growth promoter (AGP), 2 = Negative control diet (NC) without AGP, 3 and 4 = Diets without AGP added with 2500 and 5000 ppm HS, respectively. HS were extracted from a vermicompost made of sheep and pig manure using an alkaline solution and added in dry form to the feed. A basal sample of 5 cm of jejunum was taken from 10 piglets at weaning; the same was done on d 3 and 7 post-weaning, selecting 5 piglets per treatment. The samples were processed to apply different stains: () eosin and hematoxylin for morphometric analysis: villus height, villus thickness, villus area, crypt depth and the villus eight to crypt depth ratio; 2) Pass Schiff to quantify neutral goblet cells; 3) Alcian Blue pH 1.0 for heavily sulfated goblet cells; and 4) Alcian Blue pH 2.5 for non-sulfated acid goblet cells. Ten villi per animal were evaluated. Images were analyzed with Leica interactive measurement software. The results were subjected to ANOVA in a randomized complete block design. Regarding the histology of villus in the jejunum, on d 3 post-weaning the pigs added with HS had a greater villus height (3 = 317.75, 4 = 310.46 vs 2 = 278.08 and 1 = 307.12 µm; P &amp;lt; 0.05; SEM = 10.86), villus width (3 = 94.64, 4 = 95.04 vs 2 = 85.39, and 1 = 93.51 µm; P &amp;lt; 0.01; SEM = 2.32); and villus area (3 = 95841, 4 = 93678 Vs 2 = 76646 and 1 = 93471 µm2; P &amp;lt; 0.01; SEM = 4343), compared with the NC. The crypt depth was greater in piglets added with HS (3 = 236.78, 4 = 241.85 vs 1 = 194.65 and 2 = 203.01 µm; P &amp;lt; 0.01; SEM = 6.57) compared with the PC and NC. On d 7 postweaning, the piglets added with HS showed greater villus height (3 = 293.24, 4 = 282.45 vs 1 = 258.95 and 2 = 253.03 µm; P &amp;lt; 0.01; SEM = 7.89); villus area (3 = 101354, 4 = 94,575 vs 1 = 85,633 and 2 = 82,125 µm2; P &amp;lt; 0.01; SEM = 3818) and crypt depth (3 = 326.82, 4 = 337.28 vs 2 = 283.88 and 1 = 321.53 µm; P &amp;lt; 0.01; SEM = 8.285) compared with the PC and NC. The number of neutral, heavily sulfated and non-sulfated goblet cells at 3 and 7 d post-weaning were significantly reduced in all treatments compared with weaning; but with the addition of HS a greater number (P &amp;lt; 0.05) of goblet cells per villus were shown. The results suggest that HS from vermicompost improves the intestinal morphometry and increases the number of goblet cells that produce protective intestinal mucus at 3 and 7 d post-weaning in pigs.

PSIV-25 Utilization of rumen protected lysine and methionine in beef feedlot diets: Impacts on steer performance

Abstract Our objective was to compare intake, gain, and feed efficiency of steers fed rumen protected lysine and/or methionine in 10% crude protein diet relative to performance of steers fed a diet with 13% crude protein without added amino acids. Beef steers [n = 161; body weight (BW) = 429.7 ± 44.5kg] were used in this experiment. Calves were randomly assigned to treatments consisting of 1) positive control diet (POS), formulated to contain 13.0 to 13.5% CP, 2) negative control (NEG) diet containing 10.2% CP, which also forms the basal diet for the remaining treatments, 3) rumen protected methionine (RPMet) 10.2% CP basal diet and 7.2 g/d supplemental methionine, 4) rumen protected lysine (RPLys) 10.2% CP basal diet and 18.5 g/d supplemental lysine, and 5) the combination of rumen protected lysine and methionine (RPMet+Lys) 10.2% basal diet with 7.2 and 18.5 g/d supplemental methionine and lysine, respectively. Initial and final BW were unaffected by treatment (P ≥ 0.24). Average daily gain for POS (1.93 kg/d P ≤ 0.02) was greater than those of NEG, RPLYS, and RPMET+LYS, but was similar to RPMET (1.86 kg/d; P = 0.17). Dry matter intake was greater in RPMET (12.1kg/d; P ≤ 0.10) compared with all other treatments. Gain-to-feed ratio was greatest in POS (0.170 kg gain:kg DMI; P ≤ 0.04). The impacts of rumen-protected amino acids on performance (intake, gain, and efficiency) of beef steers fed high-concentrate diets were inconsistent. Evaluating both lysine and methionine supplied independent of each other in various concentrations is critical before moving forward with recommendations for beef cattle. USDA is an equal opportunity provider and employer.

PSII-19 Effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase on growth performance and intestinal measurements in broiler chickens

Abstract Poultry feeds primarily comprise plant ingredients such as cereal grains and cereal by-products that are high in non-starch polysaccharides (NSPs). However, poultry has limited digestive enzymes to efficiently utilize NSPs, and therefore, exogenous NSP-degrading enzymes (NSPase) are typically supplemented to poultry diets. Xylanase is the most widely used as NSPase in poultry diets because xylanase degrades arabinoxylans which is in increased amounts in most feed grains like corn and wheat, thereby improving dietary nutrient utilization and subsequent productive performance. β-glucanase is another potential exogenous NSPase used to degrade β-glucans present in plant ingredients. Although the benefits of dietary xylanase are well-documented, limited information regarding effects of dietary xylanase and β-glucanase complex is available. Therefore, this study aimed to investigate the effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase on growth performance and intestinal measurements in broiler chickens. A total of four hundred 8-d-old male and female Ross 308 broiler chicks were randomly allotted to 1 of 4 dietary treatments with 10 replicates. Each replicate had 5 male and 5 female birds. Dietary treatments included a positive control (PC) diet with adequate energy and nutrients, a negative control (NC) diet with high NSP-containing ingredients and less AMEn by 100 kcal/kg than PC diet, and 2 NC-based diets supplemented with 0.1% xylanase (4,000,000 units/kg) or 0.1% xylanase-glucanase complex (4,000,000 units/kg xylanase and 2,000,000 units/kg β-glucanase). The experiment lasted for 28 d. For intestinal measurements including jejunal morphology and ileal digesta viscosity, 1 male chicken per replicate was selected based on the body weight at the end of the experiment. Results indicated that birds fed PC diets had less (P &amp;lt; 0.05) FCR than those fed NC diets (Table 1). Birds fed diets supplemented with xylanase alone or combination of xylanase and β-glucanase had also less (P &amp;lt; 0.05) FCR than those fed NC diets. No difference in FCR was observed between birds fed PC diets and those fed diets supplemented with xylanase alone or combination of xylanase and β-glucanase. However, dietary treatments had no effects on body weight, body weight gain, and feed intake of broiler chickens. Jejunal villous height to crypt depth ratio (VH:CD) was greater (P &amp;lt; 0.05) for birds fed PC diets or diets supplemented with combination of xylanase and β-glucanase than those fed NC diets (Table 2). Feeding diets supplemented with xylanase alone or combination of xylanase and β-glucanase decreased (P &amp;lt; 0.05) ileal digesta viscosity as compared with feeding NC diets (Table3). In conclusion, feeding high NSP and low energy diets supplemented with either 0.1% xylanase alone or 0.1% xylanase and β-glucanase complex results in similar productive performance of broiler chickens as compared with feeding typical corn-soybean meal-based diets possibly due to improved intestinal structure and decreased digesta viscosity.

375 The effects of protease supplementation on weaned piglet performance and intestinal function fed greater amounts of lower digestible protein sources

Abstract The present study investigated the impact of dietary protease supplementation on the growth performance and intestinal function of weaned piglets when fed a diet comprising high levels of low digestible protein sources, in comparison with a standard commercially representative piglet diet. A total of 180 weaned piglets, 21 d old, of Duroc × Large White × Landrace crossbreeds, with an initial body weight (BW) of 6.27 ± 0.45 kg, were randomly assigned to three dietary treatments: 1) a standard commercial positive control (PC) diet comprising 22.2% soy protein, 5% whey protein, and 3% fish meal, 2) a negative control (NC) diet comprising 30.1% soy protein without whey protein and fish meal, and 3) a NC diet supplemented with 0.02% protease (NC + PROT). The diets were formulated to be iso-nitrogenous and iso-caloric and were pelleted at conditions of 0.4 MPa and 75°C. The experimental design employed a completely randomized design with 6 replicate pens per treatment, each pen containing 10 piglets. Statistical analysis was conducted using one-way ANOVA, with differences between means assessed using Duncan’s Multiple Range Test (P &amp;lt; 0.05). In terms of piglet performance, feeding the NC diet, containing high levels of low digestible protein sources, resulted in a significant decrease (P &amp;lt; 0.05) in final BW, average daily gain (ADG), and average daily feed intake (ADFI) by 3.1%, 8.2%, and 5.2%, respectively, compared with piglets fed the PC diet. Conversely, the NC diet significantly increased (P &amp;lt; 0.05) the feed-to-gain ratio and incidence of diarrhea by 3.4% and 88.3%, respectively, relative to PC. However, the supplementation of protease in the NC + PROT diet restored final BW, feed-to-gain ratio, and incidence of diarrhea to the same level as PC, while ADG and ADFI were increased (P &amp;lt; 0.05) by 4.6% and 4.3%, respectively. Regarding intestinal function, relative to PC, piglets fed the NC diet exhibited significantly less (P &amp;lt; 0.05) duodenal villus height, crude protein digestibility, and gene expressions of duodenal peptide transporter PepT1 and jejunal amino acid transporter b0,+AT, while blood urea nitrogen and diamine oxidase concentrations were greater (P &amp;lt; 0.05). However, the addition of protease in the NC diet reinstated measures of intestinal function, as NC + PROT-fed piglets showed similar duodenal villus height, crude protein digestibility, gene expressions of duodenal peptide transporter PepT1 and jejunal amino acid transporter b0,+AT, as well as blood urea nitrogen and diamine oxidase concentrations to PC. In conclusion, dietary supplementation of protease in weaned piglets fed higher levels of lower digestible protein sources mitigated losses in growth performance and intestinal functionality by enhancing intestinal development, protein digestibility, nutrient transport efficiency, and overall health status of piglets.

Effects of feeding earthworm or vermicompost on early life performance of broilers under challenging dietary conditions

We investigated if feeding earthworms (EW) or vermicompost (VC) to broilers improves performance and aids in coping with dietary challenges from a soluble non-starch polysaccharide (NSP)-enriched diet (negative control diet; CON-). Newly-hatched male Cobb-500 birds (N = 480) were fed either a positive (+) control diet (CON+, n = 240) or CON+ supplemented with either 1% EW (CON+EW; n = 120) or 1% VC in DM (CON+VC; n = 120) for 8 d (Period 1; P1). At the end of P1, blood and intestinal samples were taken from half the birds in each group. Half of remaining birds on CON+ stayed on CON+ for further 8 d (P2; d9-16) or switched to CON-. Birds on CON+EW and CON+VC in P1 were switched to CON- in P2 (CON-EW and CON-VC, respectively). The CON+VC improved (P < 0.05) BW and ADG in P1 through an elevated feed intake (FI) (P < 0.05) with no effect on FCR. CON+EW did not differ from the CON+ in terms of growth and FI in P1. In P2 CON- did not affect growth or DMI relative to CON+. In the end of P2, 10% of CON+ birds had pasty vent (PV). CON- increased incidence of PV and CON-VC aggravated this effect (P < 0.05), whereas CON-EW did not differ from CON+. CON- diet reduced proportion of 16S rDNA in colon digesta (P = 0.049), while CON-EW and CON-VC did not differ from CON+. Compared to CON-, CON-EW tended to decrease (P = 0.072) incidence of PV. Ceca were heavier (P < 0.05) in CON-EW than in CON+ fed birds. In conclusion, the challenge diet induced PV and reduced bacterial 16S rDNA in colon digesta, likely due to soluble NSP-induced anti-nutritive effects. VC supplementation enhanced early growth by increasing feed intake. Provision of EW did not impact performance but decreased incidence of PV and increased cecal size, suggesting that potential inoculation with beneficial microorganisms may counteract NSP effects.

Intestinal Microbiome Profiles in Broiler Chickens Raised with Different Probiotic Strains.

The composition of the intestinal microbiota can influence the metabolism and overall functioning of avian organisms. Therefore, the objective of this study was to evaluate the effect of three different probiotics and an antibiotic on the microbiomes of 1.400 male Cobb® broiler raised for 42 days. The experiment was conducted with the following treatments: positive control diet (basal diet + antibiotic); negative control diet (basal diet without antibiotic and without probiotic); basal diet + Normal Avian Gut Flora (NAGF); basal diet + multiple colonizing strain probiotics (MCSPs); and basal diet + non-colonizing single strain probiotics (NCSSPs). The antibiotic (enramycin-antibiotic growth promoter) and probiotics were administered orally during all experiment (1 to 42 days), mixed with broiler feed. To determine the composition of the microbiota, five samples of ileal digesta were collected from 42-day-old chickens of each experimental group. The alpha and beta diversity of the ileal microbiota showed differences between the groups. MCSPs presented greater richness and uniformity compared to the positive control, negative control, and NCSSPs treatments, while the negative control exhibited greater homogeneity among samples than NCSSPs. MCSPs also showed a higher abundance of the genus Enterococcus. There were differences between the groups for low-abundance taxa (<0.5%), with NAGF showing higher levels of Delftia, Brevibacterium, and Bulleidia. In contrast, NCSSPs had a higher abundance of Ochrobactrum, Rhodoplanes, and Nitrospira. It was concluded that the treatments analyzed in this study induced modulations in the ileal microbiota of the chickens examined.

Effects of graded levels of dietary microbial 6-phytase on performance, intestinal histomorphology, caecal microbial population and short-chain fatty acid composition of Lohmann white-classics

ABSTRACT 1. This study was conducted to determine the effects of graded levels of phytase on the performance, egg quality and gut health of white laying hens. 2. Treatments consisted of a negative control (NC) diet containing 0.14% available phosphorus (avP), positive control (PC) diet containing 0.35% avP provided via dicalcium phosphate (DCP) and DCP replaced in the PC by with three graded levels of phytase derived from Komagataella phaffii at 500 (PC-500), 750 (PC-750) and 1000 (PC-1000) FTU/kg which provided 0.176%, 0.188% and 0.200% of avP, respectively. 3. Egg production, feed intake, feed conversion ratio and jejunal morphometry were negatively affected in NC-fed birds (p < 0.05). Considering the whole period, birds fed a diet supplemented with graded levels of phytase shared the same egg production and feed intake levels with PC birds (p < 0.05). Feed conversion ratio was significantly lowered by 4.9%, 1.6% and 7.6% in hens fed on diets PC-500, PC-750 and PC-1000, respectively compared to those fed the PC (p < 0.05). 4. Neither of the dietary treatments affected cracked eggs, dirty eggs, eggshell breaking strength and eggshell thickness. Dietary supplementation of phytase significantly increased villus surface area by 15%, 36% and 40% in PC-500, PC-750 and PC-1000 birds, respectively compared to PC (p < 0.05). 5. A significant increase in lactobacillus count was observed in line with increasing the level of phytase (p < 0.05). Dietary treatments had no effect on the caecal coliform or aerobic populations. Furthermore, phytase supplementation significantly increased the concentrations of total caecal short-chain fatty acid (SCFA; p < 0.01). 6. In conclusion, along with improving performance parameters, the inclusion of phytase in laying hen diets can ameliorate intestinal morphology and stimulate caecal microflora and increase SCFA concentrations.

Effect of L-Glycine on Carcass Parameters, Blood Biochemicals, and Jejunal Histomorphometry of Commercial Broiler Chicken

A study was conducted for duration of six weeks on 240, day-old Cobb-430Y broiler strain chicks and randomly distributed to four groups each containing three replicates and 20 chicks per replicate. Group A was Negative Control (NC) contained 3% Low Protein (LP) diet containing 19.50, 18.00 and 16.50% crude protein (CP) for broiler pre-starter, starter and finisher phases, respectively. Positive Control (PC) group B contained standard protein 22.50, 21.00, and 19.50% CP as per breeder recommendation. No L-Glycine was added to NC and PC diets. Group C (NC+Gly1) was formulated by adding 0.640, 0.810, and 0.630% L-Glycine in NC diet to arrive 2.30, 2.30, and 2.00% digestible (Dig.) Gly + Ser levels while group D (NC+Gly2) was formulated by supplementation of 0.755, 0.985, and 0.740% L-Glycine in NC diet to arrive 2.40, 2.40, and 2.10% digestible Gly + Ser levels in broiler pre starter, starter and finisher diets respectively. Digestible Gly + Ser levels of NC group were 1.71, 1.56 and 1.43%; and of PC group were 2.02, 1.91 and 1.76%, respectively for broiler pre starter, starter and finisher diets. Ratio of dig. Met, Thr, Trp, Arg, and Val. ratioed to Lys. were balanced in all diets. All diets were isocaloric (3010, 3100, and 3200 kcal ME /kg) for broiler pre starter, starter and finishaer phases, respectively. Results showed that the L-Glycine supplementation in AA-balanced 3% LP diet did not affect per cent eviscerated yield, giblet yield, ready-to-cook yield, and breast meat yield but helped to reduce abdominal fat without altering serum biochemical parameters. Dig. Gly + Ser levels of 2.30, 2.30, and 2.00% (L-Glycine levels of 0.640, 0.810, and 0.630%) in 3% low protein (19.50, 18.00, and 16.50% CP) for broiler pre starter, starter and finisher diets helps to improve jejunal crypt depth leads to increasing cell renewal rate and maturation in the gut. Incorporation of L-Glycine is recommedded to maintain Dig. Gly + Ser levels of 2.30, 2.30, and 2.00% in broiler pre starter, starter and finisher phases with reduction of 3% CP in breeder recommended commercial broiler diet. Reducing dietary crude protein using L-Glysine without harming broiler performance could be economical.

A New Biosynthetic 6-Phytase Added at 500 Phytase Unit/kg Diet Improves Growth Performance, Bone Mineralization, and Nutrient Digestibility and Retention in Weaned Piglets and Growing-Finishing Pigs.

Two experiments were performed to evaluate the effect of a biosynthetic 6-phytase added at 500 phytase unit (FTU)/kg diet on growth performance, bone mineralization, and nutrient digestibility and retention in weaned piglets and growing-finishing pigs. Experiments were performed on 90 weaned male and female piglets with an average initial body weight (BW) at 7.7 ± 0.73 kg, 26 days of age) and 300 male and female growing pigs (initial BW: 21.0 ± 3.44 kg) for 43 and 98 days in experiments 1 and 2, respectively. In each experiment, the animals were assigned to one of three treatments according to a randomized complete block design. The treatments consisted of a positive-control (PC) diet formulated to meet nutrient requirements; a negative-control (NC) diet reduced similarly in calcium (Ca) and digestible P by 0.15 and 0.12% points in phases 1 and 2, respectively, in piglets and by 0.14, 0.11, and 0.10% points, respectively, in phases 1, 2, and 3 in growing-finishing pigs, compared with PC diet; and a NC diet supplemented with the new 6-phytase at 500 FTU/kg diet (PHY). The dietary P and Ca depletion reduced (p < 0.05) the final BW (-11.9%; -7.8%,), average daily gain (ADG, -17.8%; -10.1%), average daily feed intake (ADFI, -9.9%; -6.0%), gain-to-feed (G:F) ratio (-8.9%; -4.6%), and apparent total tract digestibility (ATTD) of P (-7.7% points; -6.7% points) in nursery piglets and growing pigs, respectively. It also decreased (p < 0.001) P and Ca retention by 6.1 and 9.4% points, respectively, in nursery pigs and ash, P, and Ca contents in metacarpal bones by 18.4, 18.4, and 16.8%, respectively, in growing pigs. Compared to animals fed the NC diet, phytase supplementation improved (p < 0.001) the final BW (+7.7%; +11.3%), ADG (+12.5%; +15.0%), G:F ratio (+8.4%; +5.8%), ATTD of Ca (+10.8% points; +7.2% points), and ATTD of P (+18.7% points; +16.6% points) in weaned piglets and growing pigs, respectively. In addition, phytase also increased (p < 0.001) P and Ca retention by 6.1 and 9.4% points, respectively, in nursery pigs and ash, P, and Ca contents in metacarpal bones by 17.7, 15.0, and 15.2%, respectively, in growing pigs. The final BW, ADG, G:F ratio, and bone traits in animals fed the NC diet supplemented with phytase were comparable to animals fed the PC diet. This finding indicates the ability of this novel biosynthetic phytase to restore performance and bone mineralization by improving the availability of P and Ca in piglets and growing pigs fed P- and Ca-deficient diets.

47 Application of a ‘high’ or ‘low’ energy matrix to a nutrient-reduced diet supplemented with a novel phytase maintained growth performance and conferred production and sustainability benefit

Abstract This study assessed the capacity of a novel consensus bacterial 6-phytase variant (PhyG) to maintain growth performance of weaned pigs when added to a nutrient-reduced mixed cereal diet with two levels of dietary net energy (NE) reduction applied. A total of 360 newly weaned pigs [Greater York × Norsvin Landrace; initial body weight (BW) 8.4 ± 0.78 kg] were assigned to 60 floor-pens and 5 dietary treatments in a randomized complete block design. There were 2 blocks (weaning group), 6 replicate pens per block, and 6 pigs/pen (3 male, 3 female), in total of 12 replications per treatment. Diets were based on wheat, corn, barley, and soybean meal and were offered to pigs in 2 phases in pelleted form (0–14 and 14–35 d post-weaning). Treatments comprised a nutritionally adequate positive control (PC) and 4 negative control (NC) diets supplemented with PhyG. The NC diets were reduced in digestible P, Ca, Na, and digestible amino acids vs. PC, according to the expected contribution of PhyG added at 1,000 phytase units (FTU)/kg (NC1) or 2,000 FTU/kg (NC2), respectively. Each NC1 and NC2 was formulated at two NE reduction levels, designated ‘low’ and ‘high’ (‘low’: -53 to -65 kcal/kg and ‘high’: -73 to -86 kcal/kg, vs. PC at 1,000 and 2,000 FTU/kg PhyG, respectively). Data were analyzed by ANOVA. Means separation was by Tukey’s HSD test. During both phases and overall (0–35 d), average BW, average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) in all PhyG-supplemented, nutrient- and NE-reduced treatments, were either not different or were improved compared with the PC. Overall ADG, ADFI, and final BW (d 35) were greater in NC2+PhyG 2,000 FTU/kg ‘low’ vs. PC (466 vs. 424 g, 9.9%, 622 vs. 567 g, 9.7%, and 24.7 vs. 23.1 kg, 6.9%, respectively; P &amp;lt; 0.05). Total feed costs (ingredients price, February 2023) and estimated carbon footprint (CFP; FeedPrint, WUR, The Netherland) per kilogram of BW gain (BWG) were reduced in all PhyG-supplemented, nutrient- and NE-reduced treatments vs. PC. Feed costs saving per kg BWG were greater with ‘high’ than ‘low’ NE reduction applied (-0.013 vs. -0.007 €, respectively, vs. PC) with PhyG at 1,000 FTU/kg, and it was greatest in NC2+PhyG 2,000 FTU/kg with ‘low’ NE reduction (-0.036 € vs. PC). Similarly, the CFP was reduced from 2,068 to 1,840 g CO2 eq/kg BWG (-11 %) by NC2+PhyG 2,000 FTU/kg with ‘low’ NE reduction vs. PC. In conclusion, the application of a full nutrient matrix with ‘high’ or ‘low’ NE reduction combined with supplementation of PhyG maintained growth performance of weaned pigs and reduced the total feed costs and carbon footprint per kg BW gain, lead to production and sustainability benefits.

260 Effect of different doses of phytase (HiPhorius) and two primary calcium sources on nutrient digestibility, retention and blood parameters in weaned piglets

Abstract An 18-d study evaluated the effect of increasing phytase levels in diets with limestone or Ca-formate on Ca and P digestibility, P retention, and blood inositol, Ca, and P in weaned piglets. At weaning, male piglets [n = 60; 29.8 ± 1.10 d of age; initial body weight (BW) = 8.8 ± 0.31 kg) were randomly allocated to ten diets formulated as a 2 × 5 factorial design with 2 primary Ca sources (limestone or Ca-formate) and 5 Ca/P levels. There was a positive control diet (PC; 0.76% Ca, 0.34 dP) and 4 negative control diets (NC; 0.56% Ca, 0.34% dP) supplemented with phytase at 0, 750, 1,500, and 3,000 FYT/kg. At d 10, piglets were individually housed in metabolism crates and fed 3.2 x metabolic weight. On d 14 to 18, fecal and total urine samples were collected. Apparent total tract digestibility (ATTD) was calculated for dry matter (DM), organic matter (OM), crude protein (CP), ash, Ca, and P using TiO2 as marker. Urinary P was measured to calculate P retention. These data were analyzed as a 2-way interaction. On d 0 (baseline), 8 and 18, blood samples were collected to analyze serum Ca and P, and plasma inositol. Blood data were analyzed as a 3-way interaction. Results indicated that piglets fed Ca-formate had greater ATTD of Ca (75.0% vs. 71.4%, P &amp;lt; 0.01) but decreased ATTD of P (66.4% vs. 68.8%, P &amp;lt; 0.01), than piglets fed limestone. Phytase supplementation improved ATTD of DM, ash, OM, CP, P, and Ca compared with the NC and PC. An interaction between Ca/P levels and Ca-sources was observed for urinary P (P = 0.03), as there were no differences between Ca sources in piglets fed the NC or the 750 FYT diets, but piglets fed the PC diet and the NC+1,500 or 3,000 FYT with limestone had greater urinary P compared with Ca-formate. A 2-way interaction between Ca/P levels and d was observed for plasma inositol (P = 0.012). On d 8 and 18, there was no difference between the NC and PC;, however, phytase supplementation at 750, 1,500, and 3,000 FYT increased plasma inositol on d 8 (58.2, 80.7, and 89.5 μmol) and d 18 (70.2, 85.4, and 106.4 μmol). There was only a main effect of Ca/P levels in serum P. Compared with the NC (73.7 mg/L), the PC and the NC+750, 1,500, and 3,000 FTU/kg increased serum P (90.3, 89.1, 87.6, and 93.2 mg/L, respectively, P &amp;lt; 0.01). There was no effect of Ca source on blood inositol and P. No significant dietary treatment effects were observed in serum Ca. In conclusion, using Ca-formate instead of limestone increases Ca digestibility but reduces P digestibility, likely due to a greater Ca solubility of Ca-formate. This suggests that diets should be formulated based on digestible Ca instead of total Ca.

145 Performance, postweaning diarrhea, and apparent total tract nutrient digestibility responses of weanling pigs to nucleotide supplementation of low-protein diets

Abstract Feeding low protein (LP) diets to nursery pigs has been reported to improve intestinal health, reduce incidence of post-weaning diarrhea (PWD) and nitrogen excretion. However, these benefits are often undermined by significant reduction in growth performance. This study evaluated the effects of low protein diets supplemented with dietary nucleotides on growth performance, post weaning diarrhea and nitrogen utilization. A total of 210 piglets (Duroc × Landrace × Yorkshire) were weaned at 21 d of age and allowed a 3-d adaptation to a common solid post weaning diet. At 24 d old, pigs were reweighed (6.02 ± 0.05 kg) and allocated to 5 dietary treatments in a completely randomized block design to give 7 replicates per treatment (n = 6 piglets per replicate). The 5 dietary treatments included i) a high protein positive control diet (PC) with 24% crude protein (CP); ii) a low protein negative control (NC) with 16% CP; iii) NC with 0.1% dietary nucleotide inclusion (NC01); iv) NC with 0.3% dietary nucleotide inclusion (NC03); and v) NC with 0.9% dietary nucleotide inclusion (NC09). All diets were corn-soybean meal based, supplemented with lysine, methionine, tryptophan, and threonine, with all low protein diets (LP) additionally fortified with crystalline isoleucine, and valine to meet the ideal amino acid requirements. Diets were provided ad libitum for 35 d and weekly feed intake (FI) and body weight (BW) were measured. On d 35, blood and fecal samples were collected to determine serum metabolites and nutrient digestibility respectively. Data were analyzed by PROC GLM and orthogonal polynomial contrast of SAS. Comparison between positive and negative control diets and nucleotide levels were performed with orthogonal contrast analysis. Relative to PC, NC diet had decreased overall average daily gain (343.5 vs. 305.5 g/d), incidence of PWD (2.5 vs. 1.2 fecal consistency score), blood urea nitrogen (BUN; 11.3 vs. 3.4 mg/dL) and total tract digestibility of energy (81.3 vs. 80.1 %; P &amp;lt; 0.05, P &amp;lt; 0.05, P &amp;lt; 0.0001 and P &amp;lt; 0.1, respectively). Relative to PC, the NC01, NC03 and NC09 treatments had comparable average daily gain (P &amp;gt; 0.05) while maintaining reduced (P &amp;lt; 0.05) BUN and incidence of PWD. Total tract digestibility of dry matter (83.1 vs. 82.1%) and energy (81.3 vs. 80.1%) were similar between PC and NC09 treatments (P &amp;gt; 0.05). Crude protein reduction decreased serum glutathione (P &amp;lt; 0.05), but without an effect of nucleotide supplementation. Serum glucose and insulin concentrations were not different across treatments (P &amp;gt; 0.05). Results suggest that feeding LP diets supplemented with dietary nucleotide after weaning can increase protein utilization efficiency, reduce incidence of PWD while partially ameliorating the negative effects of LP diets on growth performance.

258 Nutritional strategies allowing inorganic phosphates reduction in maintaining maximum growth performance and bone mineralization in piglets

Abstract Phosphorus (P) is an essential component for optimal maintenance of growth and bone mineralization but its inclusion in animal feed is a core concern for economic and environmental concerns in ensuring sustainability of this resource. This study aimed to test impacts of different nutritional strategies such as dietary calcium (Ca) reduction and phytase superdosing for piglets fed without inorganic phosphate. A total of 147 piglets Piétrain*(Large White*Landrace) were divided among 5 experimental diets. Three levels of digestible P were tested (0.21%, 0.27%, 0.33%) by adding monocalcium phosphate (MCP) from 1) a negative control diet (NC) without MCP, 2) a diet with 0.3 % MCP (NC+0.3 % MCP), or 3) a diet with 0.6 % MCP (NC+0.6 % MCP). Those three diets contained 250 FTU/kg of phytase and a minimum amount of phytate set at 0.27%. All dietary treatments were formulated following a constant Ca:digestible P ratio at 2.1. The other two diets were formulated with two phytase’ doses added on top of the NC diet 4) 2,000 FTU/kg (NC+2000 phy) or 5) 3,000 FTU/kg (NC+3000 phy). Piglets were weighed individually at 42, 55 and 69 d of age, and feed intake per phase was recorded per pen. Average daily gain (ADG), daily feed intake (ADFI) and feed conversion ratio (FCR) were calculated. At the end of the experiment, right metacarpal was removed from 12 animals per treatment to analyze bone mineralization. Data were submitted to an ANOVA including effects of dietary treatments and body weight at start of the trial using JMP 16.2.0. Differences among means were separated by a Student’s test and significance accepted at P &amp;lt; 0.05. Liveability % was not different between treatments. The reduction of Ca and digestible P in NC did not affect growth performance (P &amp;gt; 0.05) but reduced bone ash % compared with PC (P &amp;lt; 0.05, 30.4 % vs 34.6 %, respectively). Phytase supplementation at 2,000 and 3,000 FTU/kg improved body weight gain (28.8 kg for animals fed NC vs 30.0 kg for NC+2000 phy vs 30.2k g for NC+3000 phy, P &amp;lt; 0.05), feed efficiency (1.60 vs 1.50 for NC and NC + 3000 phy, respectively; P &amp;lt; 0.05) and bone mineralization (P &amp;lt; 0.05). This experiment confirms the benefit of reducing the Ca and concomitantly P levels in piglet feed without impairing growth performance by optimal use of phytase that also provides the ability to overcome dependence on inorganic phosphates.

196 Effects of zinc source and level in low ABC-4 diets on nursery pig growth performance and fecal dry matter

Abstract Incorporating pharmacological levels of Zn in nursery pig diets is a well-recognized practice for reducing post-weaning diarrhea, enhancing growth performance, and enhancing gut health. We hypnotized that the use of a specific form of ZnO (small aggregates and agglomerated particles; SAAP), which provides a greater antibacterial property than standard ZnO, could be added at reduced levels without compromising piglet performance. This study aimed to explore the effects of different levels of SAAP Zn source (HiZox, Animine, France) in low ABC-4 diets with low or high CP content. A total of 360 weanling barrows [DNA 200 × 400, initial body weight (BW) = 5.9 ± 0.4 kg] were used in a 38-d experiment. Pigs were randomly assigned to pens (5 pigs/pen) and pens assigned to 1 of 6 treatments with 12 pens/treatment. The experiment consisted of phase 1 from d 0 to 10, phase 2 from d 11 to 24, and phase 3 from d 25 to 38. Treatments consisted in a negative control (NC), which had 150 ppm of Zn (HiZox) throughout the experiment and the remaining treatments were: positive control (PC) containing 3,000 ppm (phase 1) and 2,000 ppm (phase 2) of Zn provided by ZnO; low-HiZox containing 500 ppm (phase 1) and 300 ppm (phase 2) of Zn; low-HiZox-low-CP was similar to low-HiZox but contained less CP (19.3%) than the NC, PC, low and high-HiZox diets (21.3%); high-HiZox containing 800 ppm (phase 1) and 500 ppm (phase 2) of Zn; and high-HiZox-low-CP was similar to high-HiZox but contained 19.3% CP. In phase 3, all pigs were fed a common diet containing 150 ppm of Zn (HiZox) and high CP. For the experimental period (d 0 to 24), average daily gain (ADG; quadratic, P = 0.007) and average daily feed intake (ADFI; quadratic, P = 0.018) increased as HiZox increased (Table). Pigs fed high-HiZox-low-CP had poorer gain to feed ratio (G:F; P &amp;lt; 0.05) than NC, PC, low-HiZox, and high-HiZox. Additionally, in both experimental and overall periods, pigs fed diets with low CP had decreased G:F (P = 0.043) than those fed the same Zn levels but with high CP. Overall, pigs fed high-HiZox-low-CP had decreased G:F than pigs fed high-HiZox only (732 vs. 761 g/kg, respectively; P &amp;lt; 0.05), with other treatments intermediate. For fecal dry matter (DM), pigs fed low CP diets had greater (P = 0.008) DM compared with pigs fed high CP. Thus, the inclusion of HiZox at 800 and 500 ppm in phases 1 and 2, respectively, in a low-ABC-4 diet might be a strategy to reduce the use of pharmacological levels of Zn from ZnO in nursery diets.

PSIV-17 Effects of butyrin-based additive supplementation on nursery pig performance, fecal dry matter, serum cytokines, short chain fatty acid production, and serum chemistry

Abstract Two experiments were conducted to determine the effects of butyrin-based feed additives on nursery pig performance, fecal dry matter (DM), serum chemistry, and short chain fatty acid (SCFA) production. In Exp. 1, 250 pigs (initially body weight = 5.6 kg) were randomly allotted to 1 of 5 treatments. There were 5 pigs/pen and 10 replications/treatment. Treatments consisted of a negative control, a positive control, and three diets containing various butyrin-based feed additives. The negative control was a corn-soybean meal-based diet with no antibiotics or pharmacological content of Zn or Cu. The positive control contained 3,000 and 2,000 mg/kg of Zn from ZnO in phase 1 (d 0 to 10) and 2 (d 10 to 24), respectively, 250 mg/kg of Cu from CuSO4 in phase 3 (d 24 to 38), and 55 mg/kg of carbadox (Mecadox; Phibro Animal Health Corp., Teaneck, NJ) across all phases. The butyrin-based feed additives were added at 0.1% to the negative control diet and consisted of monobutyrin, mono-tributyrin, or tributyrin. In Exp. 2, 1,492 pigs (initially 5.1 kg) were randomly allotted to 1 of 4 treatments. There were 26 or 27 pigs/pen and 14 replications/treatment. Treatments were fed over 3 phases consisting of a control diet and 3 diets containing different mono-tributyrin blends. In phase 1 and 2, the control diet contained 55 mg/kg of carbadox and 3,000 and 2,000 mg/kg of Zn from ZnO, respectively. Each feed additive was added at 0.3% to the control diet in phase 1 and 2, and 0.1% in phase 3. Phases 1 and 2 were fed by feed budget of 2.3 and 5.4 kg/pig, respectively, and phase 3 until the completion of the study. Overall, for Exp. 1, pigs fed the positive control had increased (P &amp;lt; 0.05) average daily gain (ADG) and average daily feed intake (ADFI) compared with all other treatments (Table). Pigs fed monobutyrin had decreased (P &amp;lt; 0.05) gain to feed ratio (G:F) compared with all other treatments. On d 24, pigs fed the positive control and mono-tributyrin had increased (P&amp;lt; 0.05) fecal DM compared with pigs fed monobutyrin and tributyrin with the negative control intermediate. On d 38, pigs fed mono-tributyrin had increased (P &amp;lt; 0.05) serum haptoglobin and cecal butyrate concentration compared with pigs fed the positive and negative control, respectively, with other treatments intermediate. For Exp. 2, there were no differences in growth performance throughout the study. On d 10, pigs fed mono-tributyrin blend 3 had increased (P&amp;lt; 0.05) fecal DM compared with mono-tributyrin blend 2 with other treatments intermediate. On d 24 and 42, pigs fed mono-tributyrin blend 1 had the highest (P ≤ 0.012) IL-12 concentration, without significant mean separation on d 24. In summary, butyrin-based feed additives had limited effects on growth performance. However, supplementing butyrin-based feed additives led to alterations in fecal consistency, SCFA production, and serum chemistry.

Dietary α-galactosidase and xylanase to improve the nutritional value of corn-soybean-rapeseed meal diets in broiler chickens

ABSTRACT Two experiments were performed to assess the effects of an enzyme preparation (containing α-galactosidase and xylanase) on chicken performance, carcass traits, footpad dermatitis score, and nutrient digestibility. During first experiment, chickens were fed four diets: (1) control diet (PC): corn and soybean-rapeseed meal; (2) PC supplemented with 350 ppm of the enzyme; (3) Negative control (NC): PC with a 4% reduction of apparent metabolizable energy (AME) and crude protein content; (4) NC supplemented with 500 ppm of the enzyme. In the second experiment, chickens were fed PC or PC + enzyme 350 ppm and a digestibility balance was performed. The enzyme supplementation at 350 and 500 ppm significantly improved the overall feed conversion ratio in PC and NC diet, respectively (P < 0.01). Regarding footpad dermatitis score, animals fed NC + enzyme 500 ppm tended to present a lower value than animals fed NC (P < 0.1). Concerning the digestibility balance, PC + enzyme 350 ppm diet presented a higher feed AME and AMEn value than PC diet (P < 0.05). The enzyme also improved the apparent ileal digestibility (AID) of proline (P < 0.05) and tended to increase AID of cysteine (P < 0.1). In conclusion, the enzyme preparation improves birds feed efficiency by increasing energy utilization.