250 Effects of Bunk Management and Bulk Density of Steam-flaked Corn on Growth Performance, Carcass Characteristics, and Liver Score of Finishing Beef Cattle Fed Diets Without Tylosin Phosphate

One hundred ninety-two beef steers (BW = 332 ± 8.2 kg) were used in a randomized complete block design to evaluate the effects of differing bunk management and bulk density of steam-flaked corn (SFC) in a randomized complete block design. A factorial arrangement of treatments was used with: 1) slick bunk management (SBM) + 335 g/L SFC; 2) modified ad libitum bunk management (MAL) + 335 g/L SFC; 3) SBM + 425 g/L SFC; 4) MAL+ 425 g/L SFC. Steers were randomly assigned to treatment within BW block, with 12 pen replications per treatment. Data were analyzed using a mixed model with fixed effects of bunk management, SFC bulk density, and their interaction. Block was included as a random effect. Bunk management strategy did not affect growth performance, carcass characteristics, or liver abscess score (P > 0.10). The average daily gain (ADG) of steers fed 425 g/L SFC was greater (P = 0.05) from days 35 to 105 than those fed 335 g/L SFC; however, overall ADG did not differ (P = 0.36). The DMI of steers fed 425 g/L SFC was greater (P ≤ 0.05) than those fed 335 g/L SFC. Gain-to-feed of steers fed 425 g/L SFC tended (P = 0.10) to be lesser from days 0 to 35 but did not differ overall (P ≥ 0.12). Steers fed 425 g/L SFC tended to have greater backfat and calculated empty body fat (P ≤ 0.07) than those fed 335 g/L SFC and had a greater calculated yield grade (P = 0.05). Steers fed 425 g/L SFC had 43.51% fewer (P = 0.04) liver abscesses. Bunk management strategy did not impact growth performance or carcass characteristics; whereas, SFC processed to 425 g/L increased DMI, fat thickness, and yield grade while resulting in a decreased proportion of liver abscesses.

278 Replacing cottonseed meal and sorghum grain with corn dried distillers grains with solubles in lamb feedlot diets: volatile compounds from cooked lamb chops

Dorper ram lambs (n = 46) were fed diets replacing cottonseed meal (CSM) and sorghum grain with dried distillers grains with solubles (DDGS). Lambs were fed with ad libitum access to 70.9% concentrate diets for 61 d in individual pens. The positive control diet (CNTL) contained CSM, sorghum grain, and other concentrates, but no DDGS. The four treatment diets were similar to CNTL, but did not contain CSM. Corn DDGS replaced 0%, 33%, 66% or 100% of the sorghum grain in the treatment diets. Lambs fed CNTL were contrasted to those fed 0% DDGS and linear and quadratic effects were evaluated within the four treatment diets. At 48-h postmortem, the longissimus muscle was removed from the carcass, frozen, thawed, cooked, and volatiles were collected using SPME/GC/MS. One volatile, 3-methyl,1-butanol was greater (P = 0.03) in CNTL, while 0DDGS had effectively no volatile present. For linear effects, 1-heptanol (fruity aroma) and 2-pentyl furan (caramel aroma) tended to increase linearly (P = 0.06 and 0.05, respectively), while 2-butanone tended to decrease linearly (P = 0.06; fruity-green aroma) in chops as DDGS increased in the diet. Additionally, 2-heptanone (P = 0.02; banana aroma) and heptanol (P = 0.03; woody aroma) both increased linearly in chops as DDGS increased in the diet. In the quadratic effects, decanoic acid (ethyl ester; grape aroma) tended to decrease quadratically (P = 0.07), while 2-butanone, methyl pyrazine (meaty, roasted aroma), and 2-ethyl-5-methyl pyrazine (coffee, nutty aroma) tended to increase quadratically (P = 0.05, 0.09, and 0.08, respectively) in chops with an increase in DDGS. The volatiles 2,5-dimethyl pyrazine (musty, cocoa aroma) and 2,3-octanedione (warmed-over aroma) both increased quadratically (P < 0.05) in chops as DDGS increased in the diet. Except for 2,3-octanedione, volatile aroma compounds were enhanced when DDGS replaced CSM and sorghum grain in lamb feedlot diets.

275 Replacing cottonseed meal and sorghum grain with corn dried distillers grains with solubles in lamb feedlot diets: carcass characteristics and sensory panel traits

Carcass and sensory panel traits were evaluated in Dorper ram lambs (n = 46) fed feedlot diets where cottonseed meal (CSM) and sorghum grain were replaced with dried distillers grains with solubles (DDGS). In a randomized design study, lambs were individually fed ad libitum 70.9% concentrate diets for 61 d in individual pens. The positive control diet (CNTL) contained CSM, sorghum grain, and other concentrates, but no DDGS. Four treatment diets were similar to CNTL, but did not contain CSM. Corn DDGS replaced 0% (0DDGS), 33% (33DDGS), 66% (66DDGS) or 100% (100DDGS) of the sorghum grain in the treatment diets. Lambs fed CNTL were contrasted to those fed 0DDGS and linear and quadratic effects were evaluated within the four treatment diets. At 48-h postmortem, the longissimus thoracis was removed from the carcass, frozen, thawed, cooked, and evaluated by a trained sensory panel. Lambs fed CNTL had greater (P ≤ 0.03) hot carcass weight (HCW) and ribeye area (REA) than lambs fed 0DDGS. As DDGS incrementally replaced sorghum grain, HCW and flank fat quadratically increased (P ≤ .05), marbling linearly decreased (P = 0.03), ribeye area tended to linearly increase (P = 0.06), and skeletal maturity tended to linearly decrease (P = 0.06). No differences in sensory characteristics were observed (P ≥ 0.06) between lambs fed CNTL or 0DDGS. As DDGS incrementally replaced sorghum grain, juiciness linearly increased (P = 0.03), cook loss quadratically increased (P = 0.05), lamb flavor identity tended to quadratically increase (P = 0.09) and certain flavor attributes quadratically increased (brown, roasted, umami; P ≤ 0.03), quadratically decreased (metallic; P = 0.004), or linearly increased (bloody; P = 0.003). Results indicated that carcass and sensory characteristics are not negatively affected (some are enhanced) when DDGS replaces CSM and sorghum grain in Dorper lamb feedlot diets.

Fluctuations in the Microbial Community and the Volatile Organic Acids Created During Aerobic Storage of Ground Beef

ObjectivesDegradation due to microbial and chemical mechanisms occurs throughout the storage life of ground beef. These pathways are intertwined and the microbial community and the volatile organic acids (VOCs) that evolve in ground beef are dynamic. Evaluation of microbial growth using traditional culture-dependent techniques can be misleading due to the presence of unculturable organisms. Therefore, utilizing culture-independent techniques allows for a more thorough understanding of the microbial community within a meat matrix during storage life. The objective of this study was to employ 16s rRNA amplicon sequencing and VOC identification using GC–MS to explore diversity and changes of the microbial community and VOC production during shelf-life of ground beef.Materials and MethodsFinely ground beef (80/20) was procured from beef processing facilities in the West (one lot) and Midwest (two lots). The lots were separated into three physically separate replicates. Ground beef lots were transported in chub packaging to Colorado State University (Fort Collins, CO), and the chubs were stored in the dark at 2°C for either 16/17 d or 23/24 d. After dark storage, chubs were reground, and 454 g fluff-packs were placed on polystyrene trays before overwrapping with polyvinyl chloride film. The trays were placed in retail display cases maintained at 2–4°C for 5 d. Samples were collected every day of retail display for evaluation of the microbial community and VOC development. Following standardized extraction, 16S rRNA amplicon sequencing was used to explore microbial communities. Sequencing data were analyzed using the programs in the QIIME2 (version 2018.4) pipeline. Similarly, volatile organic compounds were extracted prior to analysis of targeted VOCs using a GC–MS. The project was designed as a split-plot design and was analyzed using R packages (version 3.4.3), lme4, lmerTest, and emmeans. Least squares means were separated using an α of 0.05.ResultsThe top orders of bacteria found in the meat samples were from Enterobacteriales, Lactobacillales, and Pseudomonadales. No differences (P ≥ 0.05) in Faith’s Phylogenetic Diversity Index, or a measure of diversity of the bacterial species within a sample, were observed between Days 0, 2, and 4 of retail case display. A targeted analysis identified eighteen VOCs associated with ground beef spoilage. In previous studies, the presence of hexanal, acetoin and acetic acid are identified as spoilage indicators. Hexanal, Acetoin and acetic acid increased (P ≤ 0.05) over the 5 d of retail display.ConclusionThe use of 16s rRNA amplicon sequencing technology is a relatively recent tool that has rapidly advanced the study of microbial deterioration during beef storage and shelf-life. Moreover, the combination of 16s rRNA amplicon sequencing and identification of VOCs in this study, afforded an exploration of the relationship between chemical and biological changes which occur during ground beef storage. These analytical technologies, when used in unison, can highlight the dynamic relationships and evolution of chemical and biological constituents in ground beef. Further research in ground beef shelf-life should incorporate such measures.

Beef Flavor Evaluation on Top Loin Steaks, Sirloin Steaks, Chuck Roasts, and 80/20 Ground Beef Over The Retail Case

ObjectivesConsumer acceptability in meat flavor is one of the driving factors of acceptability. Many studies have found factors that affect beef flavor, but little is known about variability of major beef cuts in the retail meat case where meat is displayed, and customers can choose from.Materials and MethodsFour beef cuts (chuck roast, top sirloin steaks, top loin steaks, and 80/20 ground beef) were obtained from retail stores in Miami, Los Angeles, Portland, New York, and Denver within a 2-mo period. The study wanted a variety of samples that were from different production systems or contained certain claims that would be available to customers. The meat was shipped with dry ice and stored at –9°C. For evaluation steaks, roasts, and ground beef were thawed 24 h at 4°C. Prior to cooking, chuck roasts were cut 10.16 × 12.7cm from the center of the roast. Each ground beef sample was formulated into 3, approximately 150 g patties. Chuck roasts were placed in a roasting pan on a roasting rack and 2 cups of water. Beef steaks and ground beef patties were cooked on a stovetop grill and cooked to 71°C, steaks and patties were flipped when temperature reached 35°F. Chuck roasts were cut into 1.27cm cubes with no visible connective tissue, fat, or outside browning. Steaks were cut into 1.27cm cubes with no connective tissue or fat. Ground beef patties were cut into 6 wedges. Panelists were served either 2 wedges or 2 1.27 cm samples for evaluation. An expert trained descriptive flavor and texture sensory panel was conducted where panelists evaluated beef flavors and textures. Beef flavor and texture attributes were analyzed using SAS (version 9.4, SAS Institute, Inc., Cary, NC) and principal component (PCA) bi-plots were generated using XLSTAT (Addinsoft, Inc., Long Island City, NY) using P < 0.05.ResultsChuck roasts were associated with bloody/serumy flavor aromatics. Ground beef patties were clustered with fat-like, overall sweet, green hay, and buttery flavor aromatics. Top sirloin steaks samples were more highly associated with off flavors such as liver, cardboardy, and sour flavor aromatics. Top loin steaks were clustered with positive attributes such as umami, beef flavor identity, and brown, roasted flavor aromatics. For the PCA biplot, factor 1 accounted for 60% and factor 2 accounted for 28% of variation. Ground beef was higher (P < 0.0001) in brown, fat like, green hay, sour milk/sour dairy, flavor aromatics, and had more salty and sweet basic taste than the other cuts. Ground beef patties had the least amount (P < 0.0001) of bloody/serumy, metallic, and liver like flavor aromatics. Chuck roasts had the least (P < 0.0001) beef flavor id, brown, roasted flavor aromatics and salt and umami basic taste. Sirloin steaks had the lowest (P < 0.0001) fat like flavor aromatic and the highest levels (P < 0.0001) of burnt and cardboardy flavor aromatics and bitter and sour basic taste. Sirloin steaks and chuck roasts had more metallic and liver like (P < 0.0001) flavor aromatics than other cuts. Top loin steaks were intermediate in flavor attributes.ConclusionFlavor descriptive attributes of four beef cuts differed. Results indicated that chuck roasts and top sirloin steaks were associated with negative flavor attributes. Ground beef contained sweeter, fat like attributes with exceptions of green hay, while top loin steaks were associated with more positive beef flavor attributes.

How Muscle Foods Are Categorized and Described in Chronic Disease Literature: A Systematic Review and Quantitative Analysis (P01-021-19)

Objectives

Qualitatively, nutrition science and policy experts recognize that variation in muscle food categories (CAT) and descriptions (DESCR) hinder effective translation of research into policy. The purpose of this systematic review was to quantitatively describe CAT and DESCR patterns in nutrition-related chronic disease literature.

Methods

We identified 3427 articles in PubMed, Cochrane, and CINHAL up to March 2018. Inclusion criteria were: 1) observational (OBS) or randomized controlled trial (RCT) designs, 2) muscle food consumption as an independent variable, 3) primary prevention of cardiovascular disease, obesity, type 2 diabetes, or cancer as a dependent variable, 4) population 19+ years, and 5) females not pregnant/lactating. We considered a CAT as the phrase researchers used to refer to a muscle food group and DESCR as the explanation of a CAT. Table 1 describes our empirical scoring scale. We used generalized linear mixed models to assess effect of publication date, one-way ANOVAs to assess differences between study designs and chronic disease types, and binary logit models to estimate probabilities of DESCR factors.

Results

We identified 1019 CAT and 833 DESCR from 369 articles. Mean CAT specificity for RCT and OBS was 2 and 3 points, respectively (out of 7; Table 1), with no differences among chronic disease types. Specificity of OBS CAT was higher in more recent publications but RCT CAT became less specific in the 2000 s compared to previous years. RCT CAT were 5x more likely to include species, 6x more likely to include leanness, but 5x less likely to include processing degree compared to OBS CAT. Among all CAT, 76% and 82% included a DESCR for OBS and RCT, respectively. Researchers described processed meat, red meat, and total meat categories more commonly than poultry or fish categories. Of processed meat DESCR provided by researchers, 31% included a common term used in publicly available regulatory definitions.

Conclusions

Muscle food categories and descriptions are substantively different within and between observational and experimental studies and do not match definitions used by regulatory agencies. A practical muscle food classification system is warranted to improve interpretation of evidence regarding muscle food consumption and chronic disease.

Funding Sources

The Beef Checkoff.

Supporting Tables, Images and/or Graphs

Vitamin K Content of Raw and Cooked U.S. Beef Variety Meat Items (FS14-03-19)

Objectives

Vitamin K is an essential nutrient that has been implicated in cardiovascular disease and other chronic diseases. There are two forms of vitamin K in nature. Phylloquinone (PK) is plant-based and has been well-quantified in the U.S. diet. Menaquinones (MK) are found in animal products and fermented food. However, the MK contents of food have not been well characterized. The objectives of this study were to: 1) quantify the different forms of MK (MK4 through MK13) in the beef variety meat items; and 2) determine if cooking has an effect on vitamin K content of beef variety meat items.

Methods

Raw beef heart, liver, kidney, tongue, honeycomb tripe, oxtail, bone marrow, beef rocky mountain oysters (RMO), fat composite samples and blood (total samples n = 31) were obtained from processing facilities in the U.S., to provide national representation of retail-ready beef variety meat items. All raw beef samples were cooked, and final internal temperature was 80 °C. PK and the MKs in raw and cooked beef variety meat items were quantified using mass spectrometry technology. Wilcoxon Rank Signed test was used to compare PK and MK contents of raw and cooked samples. Differences were considered statistically significant at P < 0.05.

Results

The highest concentration of any form was PK in bone marrow at 152 ± 11.9 ng/g. The fat composite samples contained between 20.9 ng/g to 63.0 ng/g of PK. Modest amounts of PK were found in liver, RMO and tripe. MKs were present in all samples analyzed with MK4, MK10, MK12 and MK13 present in the largest amount in the analyzed samples. MK4 concentrations in bone marrow and fat composite samples were 341 ± 116 and 374 ± 101 ng/g, respectively. Liver contained appreciable amounts of longer-chain MKs, primarily in the forms of MK11, MK12 and MK13, which together accounted for 95% of total vitamin K in liver. There were no significant differences in total vitamin K content between cooked and uncooked beef variety.

Conclusions

To the best of our knowledge, this is the first report of MK contents of U.S. beef variety meat items. The vitamin K content of beef items were not influenced by cooking (heating).

Funding Sources

Funded by the Beef Checkoff and supported by the USDA, Agricultural Research Service under Cooperative Agreement.

Generation of diurnal variation for influent data for dynamic simulation

When using dynamic simulation for fine tuning of the design of activated sludge (AS) plants diurnal variations of influent data are required. For this application usually only data from the design process and no measured data are available. In this paper a simple method to generate diurnal variations of wastewater flow and concentrations is described. The aim is to generate realistic influent data in terms of flow, concentrations and TKN/COD ratios and not to predict the influent of the AS plant in detail. The work has been prepared within the framework of HSG-Sim (Hochschulgruppe Simulation, http://www.hsgsim.org), a group of researchers from Germany, Austria, Luxembourg, Poland, the Netherlands and Switzerland.

Middle ear abnormalities during natural rhinovirus colds in adults

To determine middle ear pressure (MEP) changes during natural rhinovirus colds, adults with illness for < or = 3 days were tested by digital tympanometer daily for 5 days (study 1) or every other day for 7 days (study 2). Abnormal MEPs (< -50 or > +20 mm H2O) were found in 72% of 36 patients in study 1 (P < .001, vs. baseline of 11%) and 76% of 55 patients in study 2 (P < .001, vs. 15% of 103 healthy controls). Major abnormalities (> or = +100 or < or = -100 mm H2O) were found in 61% of patients in study 1 (P < .001, vs. baseline of 0) and 47% in study 2 (P < .001, vs. control of 5%). MEP abnormalities usually resolved by day 14. Only 1 subject developed clinically apparent otitis media. Earache or respiratory symptom scores did not correlate with MEP abnormalities. These results indicate that natural rhinovirus colds in adults are frequently associated with marked but transient MEP abnormalities.

Structure-function relationships in rat brainstem subnucleus interpolaris. I. Vibrissa primary afferents

Intra-axonal recording and horseradish peroxidase labelling techniques were used to examine structure-function relationships for vibrissa-sensitive primary afferent fibers (N = 40) in rat trigeminal brainstem subnucleus interpolaris (SpVi). All responded at short (mean-0.42 ms) latencies to trigeminal ganglion shocks and to innocuous stimulation of an individual vibrissa in a slowly adapting type I, slowly adapting type IIa, slowly adapting type IIb, low-velocity-sensitive rapidly adapting, or high-velocity-sensitive rapidly adapting fashion. As in the medullary dorsal horn (Hayashi, '82; Jacquin et al., '86a), functionally distinct mystacial vibrissae-related fibers were morphologically indistinguishable. Each gave rise to up to ten collaterals that entered interpolaris perpendicular to the long axis of the nucleus and often overlapped to form a densely packed, highly circumscribed, and largely continuous column of terminal arbors. While some morphological variability was observed both within and between individual axons, variance within a given functional class was no greater than that between classes. Nonmystacial vibrissae afferent arbors also formed similar ovoid, dense circumscribed terminal plexuses. Presumably, these individual arbors collectively form a longitudinal tubelike vibrissae representation in this and other components of the trigeminal brainstem nuclear complex. The relative locations of each fiber's terminal field could be accurately predicted by the particular vibrissa innervated. Contrary to previous data obtained with similar methods (Hayashi, '82), but consistent with the findings of earlier transganglionic tracing (Arvidsson, '82) and histochemical (Belford and Killackey, '79) studies, the arbors of these fibers terminated throughout the mediolateral extent of SpVi. Axons innervating rostral vibrissae terminated medially, and those that supplied caudal vibrissae innervated the lateral SpVi. Dorsal vibrissae were represented in the ventral SpVi, while ventral vibrissae were represented more dorsally. This transverse topography extended largely throughout the rostrocaudal extent of interpolaris. In summary, the vibrissae primary afferent map in SpVi is inverted, faces medially, and is rostrocaudally consistent. In its most caudal aspect, as the displaced substantia gelatinosa swings laterally, the map is less orderly and incomplete. These generalizations also apply to the nonmystacial vibrissae afferents.