A Meta-Analysis of Essential Oils Use for Beef Cattle Feed: Rumen Fermentation, Blood Metabolites, Meat Quality, Performance and, Environmental and Economic Impact

The objective of this study was to see how dietary supplementation with essential oils (EOs) affected rumen fermentation, blood metabolites, growth performance and meat quality of beef cattle through a meta-analysis. In addition, a simulation analysis was conducted to evaluate the effects of EOs on the economic and environmental impact of beef production. Data were extracted from 34 peer-reviewed studies and analyzed using random-effects statistical models to assess the weighted mean difference (WMD) between control and EOs treatments. Dietary supplementation of EOs increased (p < 0.01) dry matter intake (WMD = 0.209 kg/d), final body weight (WMD = 12.843 kg), daily weight gain (WMD = 0.087 kg/d), feed efficiency (WMD = 0.004 kg/kg), hot carcass weight (WMD = 5.45 kg), and Longissimus dorsi muscle area (WMD = 3.48 cm2). Lower (p < 0.05) ruminal concentration of ammonia nitrogen (WMD = −1.18 mg/dL), acetate (WMD = −4.37 mol/100 mol) and total protozoa (WMD = −2.17 × 105/mL), and higher concentration of propionate (WMD = 0.878 mol/100 mol, p < 0.001) were observed in response to EOs supplementation. Serum urea concentration (WMD = −1.35 mg/dL, p = 0.026) and haptoglobin (WMD = −39.67 μg/mL, p = 0.031) were lower in cattle supplemented with EOs. In meat, EOs supplementation reduced (p < 0.001) cooking loss (WMD = −61.765 g/kg), shear force (WMD = −0.211 kgf/cm2), and malondialdehyde content (WMD = −0.040 mg/kg), but did not affect pH, color (L* a* and b*), or chemical composition (p > 0.05). Simulation analysis showed that EOs increased economic income by 1.44% and reduced the environmental footprint by 0.83%. In conclusion, dietary supplementation of EOs improves productive performance and rumen fermentation, while increasing the economic profitability and reducing the environmental impact of beef cattle. In addition, supplementation with EOs improves beef tenderness and oxidative stability.

Carcass characteristics and meat evaluation of cattle finished in temperate pasture and supplemented with natural additive containing clove, cashew oil, castor oils, and a microencapsulated blend of eugenol, thymol, and vanillin

BACKGROUND

Forty crossbred steers were supplemented with different doses (from 0 control to 6000 mg/animal/day) of natural additive blend containing clove essential oil, cashew oil, castor oil, and a microencapsulated blend of eugenol, thymol, and vanillin for 80 days. Carcass characteristics, drip loss, and antioxidant activity were evaluated 24 h post mortem on longissimus thoracis, and the effects of aging (until 14 days) were evaluated for water losses (thawing/aging and cooking), texture, color, and lipid oxidation.

RESULTS

The use of the natural additive blend did not modify (P > 0.05) carcass characteristics but did, however, modify body composition (P < 0.05). Drip losses were unaffected by the treatments tested (P > 0.05). There was an observed quadratic effect (P < 0.05) on losses from thawing/aging on the first day of storage. Regarding the effects of natural additives on cooking losses, there was a quadratic effect (P < 0.05) among the treatments on day 7 of aging. Differences between days of aging were only observed with control treatment. Shear force was similar among treatments on days 1 and 7 of aging. On day 14 a linear effect (P < 0.05) was observed. Also, a linear effect (P < 0.05) appeared on meat lightness, meat from the control group being clearer on day 1. No changes were observed in redness among treatments or days of storage (P > 0.05). Yellowness was not modified by the treatments (P > 0.05)but only by the days of storage in control and the lowest dosage used.

CONCLUSION

The blend of natural additives has potential use in pasture feeding and could improve meat quality. However, doses should be adjusted. © 2021 Society of Chemical Industry.

Influence of Phytogenic Feed Additive on Performance of Feedlot Cattle

This study evaluated the influence of a blended phytogenic feed additive on feed intake, feeding behavior, nutrient digestibility, and growth performance during feedlot adaptation, early, and late finishing periods as well as carcass traits. Twenty-six crossbred F1 Angus × Nellore bulls (19 mo ± 4 d) were housed in individually pens and fed a high-forage receiving diet for 7 days. At the end of the receiving period, bulls were weighted [initial shrunk body weight (SBW) 363 ± 20 kg], blocked by SBW and randomly assigned to two treatments; Control: without any additive or PHY: 150 ppm of a phytogenic feed additive fed throughout the adaptation and finishing phases. Bulls were transitioned through four steps over 18 days to a high-grain finishing diet (as % DM, 64% rehydrated corn grain silage, 19% corn gluten feed, 13% sugar cane bagasse and 4% minerals, urea, and vitamins mix). The finishing phase lasted 68 days, with mid-point measurements dividing early and late finishing period. The PHY group DMI was greater during adaptation and late finishing periods (P &lt; 0.05), with a tendency during early finishing period (P = 0.06). Number of daily meals was similar between treatments (P = 0.52), but an increased meal length was noted for PHY group (P &lt; 0.05), which contributed to their greater DMI. Diet digestibility remained similar between groups during the finishing periods (P &gt; 0.1). Ruminitis scores were low and liver abscess similar between treatments. Final SBW tended to be higher (P = 0.09) and hot carcass weight was greater for the PHY group (P &lt; 0.05), with no differences on dressing percentage, ribeye area and marbling score. In conclusion, the PHY treatment had positive effects on intake and carcass weight, without increasing metabolic disorders.

Sensorial, color, lipid oxidation, and visual acceptability of dry-aged beef from young bulls with different fat thickness

The reduction in slaughter age with minimum fat and dry aging process improves meat tenderness, however, its shelf-life in display has not been studied. It was evaluated the sensorial, and the color, lipid oxidation, and visual acceptance in display of dry-aged beef (0, 14, and 28 days) from young bulls slaughtered with different subcutaneous fat thickness (2.00, 3.00, and 4.00 mm). Meat with 2.00 and 3.00 mm fat had higher acceptability than 4.00 mm (p < .05). Dry aging improved overall acceptability of consumers. Meat with 2.00 and 3.00 mm fat presented higher lightness and lipid oxidation values than 4.00 mm (p < .05) but similar visual acceptance was observed. Dry-aged beef (14 and 28 days) had lower lightness, but higher redness (p < .05) than not dry aged (0 days). Display reduced color over time, for all dry-aged treatments (p < .05). Dry aging process increased lipid oxidation but these values were below 2.00 mg/kg of malonaldehyde only in the first day of display. Dry aged for 14 days had similar visual acceptability to not dry-aged beef until the third day of display (p < .05). Shelf-life of 0, 14, and 28 days of dry aged was 5.41, 2.55, and 0.23 days. Despite of the increase in lipid oxidation and lightness, the sensorial and display acceptability of meat from young bulls was not prejudiced by the reduction in fat thickness. Beef dry-aged for 14 days was visually well accepted and could be displayed for 2.55 days without compromising acceptability.

Meat quality of young bulls finished in a feedlot and supplemented with clove or cinnamon essential oils

Forty young crossbred bulls (10 ± 2.2 months of age; 219 ± 11.7 kg) were finished in a feedlot with one of five different treatments: CON, control (no essential oil); CLO450, clove essential oil (450 mg/kg); CLO880, clove essential oil (880 mg/kg); CIN450; cinnamon essential oil (450 mg/kg); and CIN880, cinnamon essential oil (880 mg/kg). Instrumental meat quality attributes and consumer acceptability aspects (visual and sensory) were assessed during meat ageing and display. The inclusion of clove essential oil showed (P = 0.033) a quadratic effect on lipid oxidation in meat evaluated under display conditions. Level of cinnamon essential oil affected (P < 0.05) pH, shear force, and meat colour. On the other hand, the diet had no effect (P > 0.05) on sensory or visual acceptability. Ageing (7 days) enhanced (P < 0.05) sensory acceptability attributes. Globally, the addition of essential oil in bull diets can be an alternative to reduces lipid oxidation without modifying sensory acceptability attributes.

Acceptability by sensory and visual analyses of meat from Nellore heifers fed with natural additives and finished in feedlots

BACKGROUND

This study evaluated the acceptability (by sensorial and visual analyses) of meat from 40 Nellore heifers (finished in feedlots for 73 days) fed with different diets supplemented with essential oils (EOs) and an active principle blend. The five diets tested were: CON - a diet without essential oil and active principle blend (eugenol, thymol, and vanillin); ROS - a diet supplemented with rosemary EO; BLE - supplemented with a blend; BCL - a diet with clove EO+ blend; and BRC - a diet with rosemary, clove EOs + blend. The acceptability of diet and aging time was evaluated by consumers.

RESULTS

Diet affected consumer acceptability and visual analysis (meat color). The diets with EO and the blend showed better sensory acceptance by the consumers; meat aged for 7 days received higher scores than meat aged for 1 day. Meat from heifers that received both EOs + blend (BCL, BRC) obtained the highest scores in the visual evaluation.

CONCLUSION

The use of natural compounds in ruminant diets improves the sensory characteristics of meat without damaging visual acceptability and may be an alternative to the conventional additive market. © 2020 Society of Chemical Industry.

Improvements in the quality of meat from beef cattle fed natural additives

Forty young bulls were fed with five different treatments (n = 8, 62 days): control, without the addition of natural additives (CON); NA15, a mixture of natural additives (1.5 g/animal/day); NA30, a mixture of natural additives (3.0 g/animal/day); NA45, a mixture of natural additives (4.5 g/animal/day); and NA60, a mixture of natural additives (6.0 g/animal/day). The hot carcass weight and dressing percentage, fat thickness, Longissimus muscle area, marbling, pH, and carcass tissue composition were measured. In addition, the instrumental meat quality (colour, water holding capacity, texture and lipid oxidation) and consumer acceptability attributes, across display were evaluated. Diet had no effect (P > .05) on the carcass characteristics evaluated (except pH). The diets significantly influenced the pH, shear force, tenderness, lipid oxidation and overall acceptability evaluated by consumers (P < .05). Globally, natural additives have some potential use in animal feed to improve meat quality.

Effect of an essential oils blend on meat characteristics of crossbred heifers finished on a high-grain diet in a feedlot

Context Natural additives have been studied to increase animal performance and the quality of meat as alternatives to the use of antibiotics. Aims The present work investigated the effects of an essential oil blend (oregano, rosemary, lemon, garlic, eucalyptus, thyme and sweet orange) incorporated into the diet of crossbred heifers on the meat quality. Methods Thirty 12-month-old half-sister crossbred heifers (1/2 Angus vs 1/2 Nellore) with an average weight of 219.8 ± 8.8 kg were allocated in individual pens for 3 months. Three diets were tested: E0.0 (without the essential oil blend); E3.5 (with 3.5 g of the essential oil blend/animal.day); E7.0 (7.0 g of the essential oil blend/animal.day). The fatty acid composition (chemical) and profile of the Longissimus muscle were evaluated. In addition, the effect of aging (1, 7 and 14 days in vacuum packs at 2°C) on the colour, cooking and thawing losses, texture, and lipid oxidation were determined. Key results The essential oil blend did not affect (P &gt; 0.05) the meat. It did not impact on the decrease in shear force, increased lipid oxidation or changes in colour with aging. Conclusions The chemical composition, water holding capacity, shear force, lipid oxidation, and fatty acid profile were not influenced by including the essential oil blend in the diet of heifers. Implications The use of low dosages of an essential oil blend could be applied in the diet of heifers, without affecting meat quality.