Skip to main content
Have a personal or library account? Click to login
Plant-Derived Essential Oils as Natural Additives for Pre-Weaned Calves: Impact on Immune System Function, Health, Performance and Ruminal Parameters Cover

Plant-Derived Essential Oils as Natural Additives for Pre-Weaned Calves: Impact on Immune System Function, Health, Performance and Ruminal Parameters

Annals of Animal Science
Volume 26 (2026): Issue 3 (August 2026)
By:   
Open Access
|Sep 2026
Figures & tables

Figures & Tables

Figure 1.

Major risk factors for calves in early life.

Figure 2.

Main therapeutic properties of essential oils.

Table 1.

Common essential oils and their main active compounds

Essential oilsSource plantsMain compoundsReference
Lavender oilLavandula angustifoliaLinalool, linalyl acetate, lavandulol, geraniolBiałoń et al. (2019)
Peppermint oilMentha × piperitaMenthol, menthone, limonene, 1,8-cineole, menthofuranBeigi et al. (2018)
Tea tree oilMelaleuca alternifoliaTerpinen-4-ol, γ-terpinene, α-terpinene, 1,8-cineoleBenchaar et al. (2007)
Eucalyptus oilEucalyptus globulus1,8-cineole, α-pinene, p-cymene, β-myrceneAlmas et al. (2021)
Lemon oilCitrus limonLimonene, β-pinene, γ-terpineneKačániová et al. (2024)
Thyme oilThymus vulgarisThymol, γ-terpinene, p-cymene, 1,8-cineole, γ-cadineneNguyen et al. (2024)
Rosemary oilRosmarinus officinalis1,8-cineole, α-pinene, camphor, verbenoneVerma et al. (2020)
Chamomile oilMatricaria chamomillaBisabolol, chamazulene, coumarins, umbelliferoneSharafzadeh and Alizadeh (2011)
Clove oilSyzygium aromaticumEugenol, eugenyl acetate, β-caryophyllene, α-humuleneHaro-González et al. (2021)
Oregano oilOriganum vulgareCarvacrol, thymol, p-cymene, γ-terpineneZamuner et al. (2023)
Figure 3.

Molecular structures of some of the most common compounds in essential oils.

Table 2.

Summary of studies on the effects of essential oils on calf immune system function

BreedNEssential oilFeeding periodRouteDoseOutcomesReference
Holstein30Rosemary4–56MR500–2000 mg/dIgG (+), Total protein (0)Biyik et al. (2023)
Holstein36Blend of EO (coneflower, yarrow, peppermint, citrus)3–60Milk4–12 ml/dIgG (0), Total protein (+), globulin (0)Jahani-Azizabadi et al. (2022)
Holstein14Blend (anise, cinnamon, garlic, rosemary, and thyme)4–60MR1 g/dBas (0), Eos (−), Lym (0), Mon (0), Leu (0)Campolina et al. (2021)
Holstein20Blend (peppermint, eucalyptus, menthol)1–28MR4 mL/dTotal protein (0), Eos (−)Coelho et al. (2023)
Holstein24Attapulgite + oregano7–67Starter1000 g/1 tIgG (0), IgM (0), IgA (0)Li et al. (2024)
Holstein20Prebiotic + blend (carvacrol, caryophyllene, p-cymete, cineole, terpinene, thymol)3–70Starter44.1 ppm/dIgG (+), IgM (+), IgA (+), Total protein (+)Liu et al. (2020)
Holstein16Sage oil14–70Milk100–200 μL/dIgG (+), IgE (0), IgM (0), IL-1β (−), IL-6 (−), TNF-α (−)Kara and Pirci (2024)
Brown Swiss48Ajwain or thyme7–67Milk1–2 ml/dTotal protein (0)Ebrahimi et al. (2018 b)
Holstein16Sage oil3–56Milk100–200 μL/dIgG (0), IgM (0), IgA (+), TNF-α (−), IFN-ɣ (−)Kara et al. (2025)
Holstein8Blend (cinnamon, oregano, and eucalyptus)10–60MR5 g/kg MRIgA (+), Total protein (0), Globulin (0), Leu (−), Lym (−)Nora et al. (2024)
Holstein75Blend (NA)14–70MR94,281 mg /dTotal protein (+), Globulin (+)Soltan (2009)

[i] EO: essential oil, MR: milk replacer, NA: not available, Ig: immunoglobulin, ml: milliliter, g: gram, mg: milligram, μL: microliter, t: ton, ppm: parts per million, lym: lymphocytes, leu: leukocytes, mon: monocytes, eos: eosinophils, bas: basophils, +: increased, −: decreased, 0: did not change.

Table 3.

Summary of studies on the effects of essential oils in diarrhea status of calves

BreedNEssential oilFeeding periodRouteDoseOutcomesReference
Holstein20Blend (peppermint, eucalyptus, menthol)1–28MR4 mL/dFecal score (0)Coelho et al. (2023)
Jersey15Green tea or oregano oil1–60N/A60 mgFecal score (0)Heisler et al. (2020)
Holstein36Blend of EO (coneflower, yarrow, peppermint, citrus)3–60Milk4–12 ml/d/milkFecal score (−)Jahani-Azizabadi et al. (2022)
Holstein × Gyr14Blend (anise, cinnamon, garlic, rosemary, and thyme)4–60MR1 g/dFecal score (0)Campolina et al. (2021)
Holstein10Oregano3–53Top-dressed in starter60 mg/kg BW/dStreptococcus (−), Escherichia (−)Ritt et al. (2023)
Holstein30Blend (thyme, lavender, sage, caper)7–42Milk100–300 mg/dFecal E. coli (−), Lactobacillus (−)Asghari et al. (2021)
Holstein20Prebiotic + blend (carvacrol, caryophyllene, p-cymete, cineole, terpinene, thymol)3–70Starter44.1 ppm/dFecal score (−)Liu et al. (2020)
Holstein16Sage oil14–70Milk100–200 μL/d/MRFecal score (0)Kara and Pirci (2024)
Holstein21Oregano4-WMR893 mg/dFecal score (0)Selvi and Tapki (2019)
Holstein48Attapulgite + oregano10 g/1000 gDiarrhea rate (−)Li et al. (2024)
Holstein18Oregano4-WMilk100–150 mg/lFecal score (−)Tapki et al. (2020)
Holstein24Mint or thymeBirth – 2 weeks post-weaningStarter0.2%/BW/dFecal score (0)Ebrahimi et al. (2018 a)
Holstein46Oregano0–10Syringe-fed12.5 mg/kg BW/dFecal score (−), days with diarrhea (−)Katsoulos et al. (2017)
Holstein23Oregano0–10Syringe-fed12.5 mg/kg BW/dFecal score (−)Katsoulos et al. (2022)

[i] EO: essential oil, MR: milk replacer, BW: body weight, kg: kilogram, d: day, ml: milliliter, g: gram, μL; microliter, mg: milligram, +: increased, –: decreased, 0: did not change.

Table 4.

Summary of the studies on the effects of essential oils in average daily weight gain, feed intake and feed efficiency of calves

BreedNEssential oilFeeding periodRouteDoseOutcomesReference
Holstein30Rosemary4–56MR500–2000 mg/d/MRADG (+), FE (+), FI (+)Biyik et al. (2023)
Holstein36Blend (coneflower, yarrow, peppermint, citrus)3–60Milk4–12 ml/d/milkADG (0), FI (0)Jahani-Azizabadi et al. (2022)
Holstein40Blend (peppermint, eucalyptus, menthol)1–28MR4 mL/dADG (0), FE (0), FI (+)Coelho et al. (2023)
Holstein20Prebiotic + blend (carvacrol, caryophyllene, p-cymete, cineole, terpinene, thymol)3–70Starter44.1 ppm/dADG (+), FE (+), DMI (+)Liu et al. (2020)
Holstein16Sage oil14–70Milk100–200 μL/dADG (+), DMI (+)Kara and Pirci (2024)
Holstein× Gyr14Blend (anise, cinnamon, garlic, rosemary, thyme)4–60MR1 g/dADG (0), FE (0)Campolina et al. (2021)
Holstein24Attapulgite + oregano7–67Starter1000 g/1 tADG (+), FCR (−)Li et al. (2024)
Holstein8Blend (cinnamon, oregano, eucalyptus)10–60MR5 g/kgADG (+), FE (+)Nora et al. (2024)
Holstein75Blend (NA)14–70MR94–281 mg /dADG (0)Soltan (2009)
Holstein10Oregano3–53Top-dressed in starter60 mg/kg BW/dayADG (0), FE (0), FI (0)Ritt et al. (2023)
Jersey15Green tea or oregano oil1–60N/A60 mg/kg BW/dayADG (0)Heisler et al. (2020)
Brown Swiss48Ajwain or thyme7–67Milk1–2 ml/dADG (0), FCR (0), DMI (0)Ebrahimi et al. (2018 b)
Holstein30Blend (thyme, lavender, sage, caper)7–42Milk100–300 mg/dADG (+), FCR (−)Asghari et al. (2021)
Holstein21Oregano4–WMR839 mg/d/MRADG (0), FE (0)Selvi and Tapki (2019)
Holstein18Oregano4–WMilk100–150 mg/l milkADG (+), FCR (0)Tapki et al. (2020)
Holstein24Mint or thyme0–74Starter0.2%/BW/dADG (+), FE (+), DMI (+)Ebrahimi et al. (2018 a)
Holstein20Blend (carvacrol, cinnamaldehyde, cineole, pepper)B–56MR200–400 mg/kg BW/MRADG (0)Santos et al. (2015)

[i] EO: essential oil, MR: milk replacer, ADG: average daily gain, BW: body weight, FCR: feed conversion ratio, FE: feed efficiency, FI: feed intake, NA: not available, d: day, kg: kilogram, ml: milliliter, g: gram, μL; microliter mg: milligram, +: increased, −: decreased, 0: did not change.

Table 5.

Summary of studies on the effects of essential oils on ruminal parameters of calves

BreedNEssential oilFeeding periodRouteDoseOutcomesReference
Holstein20Blend (carvacrol, cinnamaldehyde, cineole, pepper)B–56MR200–400 mg/kg BW/MRAA (0), BA (0), PA (0)Santos et al. (2015)
Holstein × Gyr14Blend (anise, cinnamon, garlic, rosemary, thyme)4–60MR1 g/dAA (0), BA (0), PA (0), NH3-N (0)Campolina et al. (2021)
Holstein20Prebiotic + blend (carvacrol, caryophyllene, p-cymete, cineole, terpinene, thymol)3–70Starter44.1 ppm/dAA (+), BA (+), PA (+), IVA (0), TVFA (0), pH (0)Liu et al. (2020)
Holstein × Gyr8Blend (anise, cinnamon, garlic, rosemary, thyme)4–60MR1 g/dAA (0), BA (0), PA (0), NH3-N (0)Campolina et al. (2023)
Holstein10Oregano3–53Top-dressed in starter60 mg/kg BW/dAA (0), BA (0), PA (0), TVFA (0)Ritt et al. (2023)
Holstein24Attapulgite + oregano7–67Starter1000 g/1 tAA (0), BA (0), PA (0), VA (0), IVA (0), TVFA (0), pH (0)Li et al. (2024)
Holstein30Rosemary4–56MR500–2000 mg/d/MRAA (+), BA (0), PA (+), VA (+), IVA (+), TVFA (+), pH (0), NH3-N (−)Biyik et al. (2023)
Holstein10Blend (carvacrol, caryophyllene, p-cymene, cineole, terpinene, thymol)3–42MR3.75 g/d/MRAA (0), BA (0), PA (+), VA (+), IVA (+), TVFA (+)Poudel et al. (2019)
Holstein36Blend (coneflower, yarrow, peppermint, citrus)3–60Milk4–12 ml/d/milkAA (+), BA (0), PA (+), TVFA (0), NH3-N (−)Jahani-Azizabadi et al. (2022)

[i] EO: essential oil, MR: milk replacer, AA: acetic acid, BA: butyric acid, BW: body weight, PA: propionic acid, IVA: isovaleric acid, VA: valeric acid: TVFA: total volatile fatty acids, kg: kilogram, ml: milliliter, g: gram, t: ton, ppm: parts per million, mg: milligram, +: increased, −: decreased, 0: did not change.

DOI: https://doi.org/10.2478/aoas-2025-0108 | Journal eISSN: 2300-8733 (formerly 1642-3402) | Journal ISSN: 1642-3402
Journal RSS Feed
Language: English
Page range: 1103 - 1115
Submitted on: May 1, 2025
Accepted on: Sep 23, 2025
Published on: Sep 6, 2026
Published by: National Research Institute of Animal Production
In partnership with: Paradigm Publishing Services
Publication frequency: 4 issues per year
Keywords:
essential oils,
calves,
immune system function,
diarrhea,
performance,
ruminal parameters
Related subjects:
Medicine,
Veterinary medicine

© 2026 Veysel Fatih Özdemir, published by National Research Institute of Animal Production
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 26 (2026): Issue 3 (August 2026)
Previous article
Next article