Impact of Finishing Diets with De-Oiled Distillers Grains or Antioxidant Containing Supplement on Beef Shelf Life

In its entirety this dissertation intended to address the impact of feeding several forms of de-oiled corn distillers grains plus solubles and the effect of supplementing OmniGen-AF as a potential antioxidant source for extending beef shelf life. In study one we learned that despite the de-oiling process, greater inclusion levels (65%, DM basis) of de-oiled wet distillers grains plus solubles (WDGS) causes an increase in polyunsaturated fatty acids (PUFA) similar to the levels obtained with full-fat WDGS. Lower inclusion levels (35 and 50%, DM basis) of de-oiled WDGS have intermediate PUFA content in comparison to 65% de-oiled WDGS, full-fat WDGS and a corn control diet (P \u3c 0.01). In study two cattle finished with 50% de-oiled dry distillers grain plus solubles (DDGS) also resulted in an increased PUFA content in muscle in relation to a corn control group (P \u3c 0.0001). In this instance treatment by retail display interactions indicated that steaks from cattle on the 50% de-oiled DDGS diet had lower color and lipid stability at prolonged retail display times than did the steaks from cattle on the corn control diet (P \u3c 0.0001). In general, the first two studies indicate that even after the de-oiling process and regardless of the moisture content of the distillers grains, feeding corn distillers grains plus solubles increases PUFA content, which in turn negatively impacts beef shelf life. Therefore, it is important to consider this when utilizing these by-products for finishing rations, the addition of antioxidants may be beneficial to off-set any potential detrimental effects of distillesrs grain on beef shelf life. In study three, OmniGen-AF, a potential antioxidant supplement was evaluated. OmniGen-AF supplementation all through the finishing period caused an increase in PUFA content relative to cattle supplemented only through the receiving phase (P = 0.01). Feeding OmniGen-AF all through the finishing phase however did not alter color, lipid stability, or superoxide dismutase activity (P \u3e 0.05). Therefore, in order to consider OmniGen-AF as an effective antioxidant source it may need to be fed at a greater concentration (greater than 4g/45.36kg BW/hd/d) or perhaps more potent antioxidants merit evaluation, particularly in feedlot rations utilizing corn distiller by-products. Advisor: Chris R. Calkin

The Influence of Diet and Oxidation on Calcium Retention of the Mitochondria in Fresh Beef

Feeding dried distillers grains (DG) may influence calcium flux postmortem by disrupting the stability of the sarcoplasmic reticulum (SR) membrane, thus leading to a higher post- rigor calcium leakage, resulting in greater activation of calpains and improved tenderness. Mitochondria provide the opportunity to study calcium flux in a controlled, tightly defined environment as a model system for the SR. Cattle were finished on diets containing either 0% DG or 50% DG. Feeding DG increased proportions of PUFA in the SR and mitochondrial membrane. Oxidized mitochondria retained less calcium than non- oxidized mitochondria. Mitochondria from cattle finished on corn tended to retain more Ca than mitochondria from cattle finished on DG. These findings suggest that feeding DG in the finishing diet can possibly increase meat tenderness through altered calcium flux

The Relationship between Marbling, Superoxide Dismutase, and Beef Tenderness

This study was conducted to evaluate the relationships between animal oxidative status (as indicated by superoxide dismutase [SOD] activity) to marbling and beef tenderness. Prime and Select-grade strip loins were selected and aged for 2, 7, 14, 21, and 28 days for Warner Bratzler shear force, Troponin-T, and SOD activity. Results showed that meat exhibiting higher levels of marbling had lower shear force values and thus were more tender. Low-marbled samples tended to have a greater tenderness response to aging. The effect of oxidative stress, however, was not evident in this study as SOD values were similar. Although the effects of oxidative stress on beef tenderness are still unclear, results from this study provide a conceptual foundation for a new research perspective on meat tenderness

Impact of Dietary Fat Source on Beef Tenderness

Steers were finished on either a corn control, 40% full-fat modified distillers grains plus solubles, 40% de-oiled modified distillers grains plus solubles, or 38% de-oiled modified distillers grains plus solubles plus 2% corn oil diet to evaluate the effects of dietary fat source on the mechanism of beef tenderization . Feeding modified distillers grains plus solubles increased polyunsaturated fatty acid content in the sarcoplasmic reticulum membrane and increased free Ca2+ concentration early postmortem. Steaks from cattle fed de-oiled modified distillers grains and de-oiled modified distillers grains plus corn oil were more tender at 2 d of aging when compared to corn control diet. These data indicate that feeding modified distillers grains plus solubles to cattle has the potential to increase beef tenderness early postmortem in comparison to corn diets

Impact of Dietary Fat Source on Beef Display Life

This study was conducted to evaluate the effects of dietary fat source with modified distillers grains plus solubles (MDGS) on beef display life. Steers were fed either a corn control, full-fat MDGS, de-oiled MDGS, or de-oiled MDGS plus corn oil diet. Strip loins were aged for 2, 9, 16 and 23 days and placed under retail conditions for 7 days. Results suggest that feeding MDGS to cattle increases polyunsaturated fatty acid content of beef and has the potential to reduce beef color and lipid stability in comparison to corn diets. These data indicate that feeding MDGS to cattle may decrease beef display life. Addition of corn oil to de-oiled MDGS decreased redness and increased discoloration and lipid oxidation in comparison to corn control diets

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Impact of finishing diets with de-oiled distillers grains or antioxidant containing supplement on beef shelf life

In its entirety this dissertation intended to address the impact of feeding several forms of de-oiled corn distillers grains plus solubles and the effect of supplementing OmniGen-AF as a potential antioxidant source for extending beef shelf life. In study one we learned that despite the de-oiling process, greater inclusion levels (65%, DM basis) of de-oiled wet distillers grains plus solubles (WDGS) causes an increase in polyunsaturated fatty acids (PUFA) similar to the levels obtained with full-fat WDGS. Lower inclusion levels (35 and 50%, DM basis) of de-oiled WDGS have intermediate PUFA content in comparison to 65% de-oiled WDGS, full-fat WDGS and a corn control diet (P \u3c 0.01). In study two cattle finished with 50% de-oiled dry distillers grain plus solubles (DDGS) also resulted in an increased PUFA content in muscle in relation to a corn control group (P \u3c 0.0001). In this instance treatment by retail display interactions indicated that steaks from cattle on the 50% de-oiled DDGS diet had lower color and lipid stability at prolonged retail display times than did the steaks from cattle on the corn control diet (P \u3c 0.0001). In general, the first two studies indicate that even after the de-oiling process and regardless of the moisture content of the distillers grains, feeding corn distillers grains plus solubles increases PUFA content, which in turn negatively impacts beef shelf life. Therefore, it is important to consider this when utilizing these by-products for finishing rations, the addition of antioxidants may be beneficial to off-set any potential detrimental effects of distillesrs grain on beef shelf life. In study three, OmniGen-AF, a potential antioxidant supplement was evaluated. OmniGen-AF supplementation all through the finishing period caused an increase in PUFA content relative to cattle supplemented only through the receiving phase (P = 0.01). Feeding OmniGen-AF all through the finishing phase however did not alter color, lipid stability, or superoxide dismutase activity (P \u3e 0.05). Therefore, in order to consider OmniGen-AF as an effective antioxidant source it may need to be fed at a greater concentration (greater than 4g/45.36kg BW/hd/d) or perhaps more potent antioxidants merit evaluation, particularly in feedlot rations utilizing corn distiller by-products

Impact of finishing diets with de-oiled distillers grains or antioxidant containing supplement on beef shelf life

In its entirety this dissertation intended to address the impact of feeding several forms of de-oiled corn distillers grains plus solubles and the effect of supplementing OmniGen-AF as a potential antioxidant source for extending beef shelf life. In study one we learned that despite the de-oiling process, greater inclusion levels (65%, DM basis) of de-oiled wet distillers grains plus solubles (WDGS) causes an increase in polyunsaturated fatty acids (PUFA) similar to the levels obtained with full-fat WDGS. Lower inclusion levels (35 and 50%, DM basis) of de-oiled WDGS have intermediate PUFA content in comparison to 65% de-oiled WDGS, full-fat WDGS and a corn control diet (P \u3c 0.01). In study two cattle finished with 50% de-oiled dry distillers grain plus solubles (DDGS) also resulted in an increased PUFA content in muscle in relation to a corn control group (P \u3c 0.0001). In this instance treatment by retail display interactions indicated that steaks from cattle on the 50% de-oiled DDGS diet had lower color and lipid stability at prolonged retail display times than did the steaks from cattle on the corn control diet (P \u3c 0.0001). In general, the first two studies indicate that even after the de-oiling process and regardless of the moisture content of the distillers grains, feeding corn distillers grains plus solubles increases PUFA content, which in turn negatively impacts beef shelf life. Therefore, it is important to consider this when utilizing these by-products for finishing rations, the addition of antioxidants may be beneficial to off-set any potential detrimental effects of distillesrs grain on beef shelf life. In study three, OmniGen-AF, a potential antioxidant supplement was evaluated. OmniGen-AF supplementation all through the finishing period caused an increase in PUFA content relative to cattle supplemented only through the receiving phase (P = 0.01). Feeding OmniGen-AF all through the finishing phase however did not alter color, lipid stability, or superoxide dismutase activity (P \u3e 0.05). Therefore, in order to consider OmniGen-AF as an effective antioxidant source it may need to be fed at a greater concentration (greater than 4g/45.36kg BW/hd/d) or perhaps more potent antioxidants merit evaluation, particularly in feedlot rations utilizing corn distiller by-products

The Relationship between Marbling, Superoxide Dismutase, and Beef Tenderness

This study was conducted to evaluate the relationships between animal oxidative status (as indicated by superoxide dismutase [SOD] activity) to marbling and beef tenderness. Prime and Select-grade strip loins were selected and aged for 2, 7, 14, 21, and 28 days for Warner Bratzler shear force, Troponin-T, and SOD activity. Results showed that meat exhibiting higher levels of marbling had lower shear force values and thus were more tender. Low-marbled samples tended to have a greater tenderness response to aging. The effect of oxidative stress, however, was not evident in this study as SOD values were similar. Although the effects of oxidative stress on beef tenderness are still unclear, results from this study provide a conceptual foundation for a new research perspective on meat tenderness