J. S. Moritz

Effects of modifying diet and feed manufacture concern areas that are notorious for decreasing pellet quality

SUMMARY The production of high‐quality pellets has often been described as more art than science due to the multitude of variables that affect pellet quality. The objectives of the current study were to examine the feed manufacture and pellet quality effects of 4 different feed milling concern areas. Each area of concern was evaluated using either a circumstance of low concern or a corresponding circumstance of high concern. Treatments included high or low mixer‐added fat inclusion (MAF; 2.5 vs. 0.5%), high or low distillers dried grains with solubles inclusion (DDGS; 8 vs. 2%), high or low dicalcium phosphate inclusion (DCP; 1.63 vs. 0.31%), and high or low steam conditioning temperature (79 vs. 71°C). All diets were formulated to similar nutrient specifications based on commercial broiler starter recommendations. Treatments were replicated 3 times utilizing an experimental unit of 136 kg feed allotments organized as a 4 × 2 factorial arrangement in a randomized complete block design. Contrasts were performed to better understand main effect interactions. High MAF and low DCP decreased pellet durability, percent pellets, and pellet particle size (P < 0.05). Conditions of high concern for DDGS and steam conditioning did not produce similar negative effects (P > 0.05). Extraneous variables such as corn moisture content and ambient temperature during feed manufacture likely confounded some treatment effects. A greater appreciation of variable interactive effects may benefit pellet mill operators, nutritionists, and pelleting aid vendors to better circumvent hurdles encountered during the pelleting process.

The Effects of Diet Formulation and Thermal Processes Associated With Pelleting on 18-day Broiler Performance and Digestible Amino Acid Concentration

SUMMARY The objectives of the study were to assess performance and digestible amino acid concentration of diets fed to broilers that differed in formulation and degree of thermal processing. Basal diets were corn, soybean meal (SBM), and dried distillers grains and solubles (DDGS) based and formulations were balanced to be similar in calculated metabolizable energy and digestible amino acids. Treatments were arranged in a 3 × 3 factorial that varied in diet formulation (basal, basal + meat and bone meal (MBM), and basal + bakery byproduct (BBP)) and degree of thermal processing (unprocessed mash, pellet, double pellet). All treatments were ground to similar particle size and fed to 10 replicate raised wire cages of 10 straight‐run Hubbard x Cobb 500 broiler chicks for 18 d. Broilers provided a basal + MBM diet improved FCR (P = 0.0046). Pelleting and double pelleting improved FCR compared to unprocessed mash (P = 0.0003). Formulation and processing effects interacted to affect digestible lysine, methionine, threonine, and cysteine concentrations (P < 0.05). Digestible amino acid concentration improved when basal and basal + MBM diets were thermally processed. However, digestible lysine and cysteine concentrations decreased when basal + BBP were thermally processed. In vitro available lysine results did not support digestible lysine concentration results. Thermal processing decreased trypsin inhibitor complex activity for each formulation. Nutritional benefit or detriment of thermal processes associated with pelleting was dependent on diet formulation.

Effects of yeast fermentation product inclusion during the brooder phase and grower/finisher phase feed form effects on large tom performance using feed produced at a commercial mill

SUMMARY The brooder phase (d one to 42) is crucial to overall turkey performance, and many integrators believe that the utilization of yeast products (YP) is cost effective. Pellet quality is crucial to grower/finisher phase production (d 42 to 118) due to feed form advantages during this period of high‐volume consumption. Also, feed and feed manufacture represent the largest investment required to produce poultry. The objective of this study was to establish the effects of YP (YP1 or YP2) inclusion on d one to 42 poult performance. On d 42, a 2 YP carryover x 2 feed form [intact high‐quality pellets (HQP) or ground pellets (GP)] factorial arrangement was used to measure main effects and interactions on d one to 118 tom performance. All diets had similar nutrient composition (other than YP), and feed was manufactured at a commercial feed mill. Feed form consisted of either intact HQP (average of 21.4% fines) or ground HQP (GP; average particle size of 1,108 microns). Male Hybrid Converters were reared at a facility that mimicked commercial grow‐out. On d 42, YP1 improved ending weight (EW) and FCR. No YP carryover effect was demonstrated for any of the d 42 to 118 performance variables. Feeding HQP produced toms that were 0.29 kg/bird heavier with 9 points lower FCR, as compared to toms fed GP. Regression analyses predicted that if toms fed GP finished at the same d 118 EW as those fed HQP, then FCR advantages of HQP would be 12 points. These FCR benefits may justify the increased feed costs associated with manufacturing HQP.

Effects of Environment, Feed Form, and Caloric Density on Energy Partitioning, Subsequent Performance and immune response

SUMMARY Past literature lacks studies that compare diets containing an improved feed form vs. an increased energy. The objective of the study was to assess the effect of variations of feed form and dietary caloric density on broilers reared on clean shavings and built‐up litter. Treatments were arranged in a 2 × 2 factorial randomized block design within a split plot. Whole plot treatments considered one room (11 × 7.32 m) of either clean shavings or built‐up litter; divided into 16 treatment replications of either standard (30%) or improved (80% feed form), and 16 replications of either commercial or increased (+110 kcal/kg) dietary caloric density comprising the 2 × 2 factorial arrangement. Broilers consuming an improved feed form demonstrated an improved feed intake, live weight gain, feed conversion ratio, breast weight and breast yield (P < 0.05). Providing an improved feed form demonstrated an upregulation in IgG (P < 0.05). An environment × energy interaction (P < 0.05) demonstrated upregulation of IgG in broilers fed a commercial energy reared in a built‐up litter environment, whereas broilers maintained a similar regulation of IgG when fed an increased energy regardless of environment. Linear contrasts demonstrated that broilers provided improved feed form at commercial energy increased feed intake and live weight gain (P ≤ 0.05), while maintaining feed conversion ratio (P > 0.05) compared to broilers provided standard feed form at increased energy regardless of environment. These data suggest feed form improvements may partition energy towards growth more than feeding an increased energy diet.

The effects of steam conditioning and antimicrobial inclusion on feed manufacturing and inactivation of Enterococcus faecium, a Salmonella surrogate

SUMMARY Animal well‐being, evolving feed manufacturing regulations, human health, and consumer perception drive the continued need to provide safe feed to food animals. Two experiments were conducted to determine the effects of antimicrobial inclusion and conditioning temperature variations on feed manufacturing metrics (EXP1) and the inactivation of Enterococcus faecium, a Salmonella surrogate (EXP2). Both short‐term (ST) and long‐term (LT) steam conditioning techniques were utilized in this split‐plot design where ST (10 s) or LT (60 s) steam conditioning served as whole plot units. Whole plots contained either 2 × 3 (EXP1) or 2 × 4 (EXP2) factorial arrangements varying in mixer‐added antimicrobial inclusion (with or without) and degree of thermal processing (unprocessed mash, 71°C, 82°C, and 88°C). Manufacturing of dietary treatments was replicated 3 times. A basal diet was used to obtain desired conditioning temperature before Salmonella surrogate‐inoculated feed was exposed to either ST or LT conditioning. In EXP1, conditioning time and antimicrobial inclusion interacted (P = 0.03) by decreasing pellet durability when antimicrobial was included in diets subjected to ST conditioning. Pellet durability was not affected when LT conditioning was utilized. In EXP2, conditioning time, antimicrobial inclusion, and degree of thermal processing interacted (P < 0.0001) to inactivate the Salmonella surrogate using ST conditioning at 71°C. Further inactivation from higher ST and LT conditioning temperatures, with and without antimicrobial, was apparent. Within the parameters of this study, both ST and LT steam conditioning resulted in 3 and 4‐log reductions of the Salmonella surrogate, respectively. However, degree of bacterial inactivation and pellet quality are dependent on manufacturing and antimicrobial additive strategies.

Effect of supplemental zinc source and corn particle size on 40-day broiler performance

&NA; Zinc (Zn) supplementation source and particle size of feed ingredients are two factors that can affect poultry performance and should be considered for proper feeding of poultry. The objective of the current study was to assess the effects of Zn supplementation source and corn particle size on broiler performance, breast yield, and tibia Zn concentration. Treatments were arranged in a 5 × 2 factorial randomized complete block design with the main effects Zn treatment and corn particle size (550 micron vs. 1,050 micron). Zinc treatments included a basal diet (no added Zn), 80 mg/kg Zn sulfate, and 3 diets with 40 mg/kg Zn sulfate + 40 mg/kg of either Zn‐glycine amino acid (AA) chelate (Zn‐gly), Zn‐AA complex (Zn‐AA), or Zn bis(‐2‐hydroxy‐4‐methylthio)butanoic acid (Zn‐HMTBA). A total of 8 replications per treatment were fed to 23 broilers per pen from d one to 40. A Zn treatment x corn particle size interaction was observed for ending bird weight (EBW; P < 0.05) demonstrating that feeding small particle corn produced larger broilers except when supplemental Zn was not included. Broilers fed small particle corn or diets supplemented with Zn consumed the most feed (P < 0.05); however, FCR was decreased (P < 0.05) by 1.9 points for broilers fed large particle corn diets. Tibia Zn concentration was higher (P < 0.0001) for Zn supplemented diets, but no other treatment effects were observed. In conclusion, Zn supplement source had little effect on broiler performance; however, Zn supplementation per se optimized performance.

The effects of strain and incremental improvements in feed form on d 28 to 42 male broiler performance

&NA; Feeding high‐quality pellets to modern commercial broilers may maximize genetic potential; however, this typically requires an increased cost to produce feed. Therefore, it is important to determine if incremental improvements in feed form (FF) can increase performance of modern broiler strains. The current study was conducted to investigate the effects of feeding modest improvements in feed form (50, 60, 70, or 80% intact pellets; IP) to 2 commercial broiler strains (fast‐growing or high‐yield) on d 28 to 42 growth performance and processing variables. A common diet was manufactured to contain 80% IP, of which a portion was ground to create a total of 4 FF treatments varying in IP to ground pellet ratios: 50:50; 60:40; 70:30; and 80:20. Fast‐growing (FG) birds demonstrated improvements in body weight (BW), BW gain (BWG), and feed conversion ratio (FCR) when compared to high‐yield (HY) birds. For the main effect of FF, feeding 80 vs. 50% IP reduced d 28 to 42 FCR. Also, feeding birds 80% IP vs. all other FF treatments improved d 28 to 42 BWG and d 42 BW. A Strain × FF interaction established that FG broilers fed 50, 60, and 70% IP diets had higher d 43 total breast yield than HY birds fed the same FF treatments; however, both strains demonstrated similar total breast yield when 80% IP were fed, which suggests that FG broilers are less sensitive and HY broilers are more sensitive to increasing FF. These data suggest a distinct benefit for feeding improved FF from d 28 to 42 to modern broilers.

The effect of poultry litter biochar on pellet quality, one to 21 d broiler performance, digesta viscosity, bone mineralization, and apparent ileal amino acid digestibility

&NA; Feeding poultry litter biochar (PLB), a product resulting from litter gasification, could decrease diet cost, maintain broiler growth performance, and decrease land application of manure. Past research observed improved pellet quality and mineral availability with dietary inclusions of 6 to 7% PLB; however, broiler performance was decreased, likely due from toxic‐heavy‐metal content (e.g., 99 ppm arsenic) and increased digesta viscosity of the particular PLB. The objective of the current study was to assess lower dietary inclusions of PLB, with decreased toxic‐heavy‐metal content, on descriptive feed manufacture, broiler performance, digesta viscosity, bone mineralization, and apparent ileal amino acid digestibility (AIAAD). Treatments were arranged as a Diet Formulation x Phytase Addition factorial in a randomized complete block design with 8 replications per treatment. Four dietary formulations were produced: positive control (PC) with 0.45% non phytate phosphorus (nPP), negative control with 0.23% nPP, and 2 or 4% PLB with 0.45% nPP. Phytase was either included at 9,500 ftu/kg or withheld. There were 8 treatments total. Contrasts comparing PC and 2 or 4% PLB also were conducted. Diets were pelleted and crumbled prior to feeding. Positive and negative control formulations and phytase addition affected bird performance as expected. Birds fed 2% PLB had increased FCR and birds fed 4% PLB had decreased LWG when compared to PC (P < 0.05). However, these performance deficiencies were corrected with phytase inclusion. Birds fed diets with PLB had similar tibia measures compared to the PC. No significant main effects, interactions, or contrast comparisons were observed for viscosity data. The incorporation of PLB into formulations without phytase increased diet AIAAD of some amino acids relative to the corresponding PC (P < 0.05). A lower toxic‐heavy‐metal PLB product (e.g., 22 ppm arsenic) provided available minerals and amino acids to diets, but performance similar to PC necessitated the addition of phytase.