Honey is often used to treat wounds in both veterinary and human medicine. Its proposed functions include stimulation of wound debridement,1,2 tissue regrowth,3 modulating inflammation,4 antibiofilm effects,5 and bacteriostatic and bactericidal properties.6,7 Honey is thought to be antibacterial due to its high osmolarity, acidic pH, hydrogen peroxide activity, and phytochemical factors, which can inhibit bacterial growth.7,8 A honey well known for its antibacterial properties is manuka honey, which is obtained from manuka bush (Leptospermum scoparium) and contains substantial amounts of methylglyoxal (MGO).9–11 Methylglyoxal harbors selective toxicity to bacterial cells, causing bacterial cell death and inhibition of bacterial replication.10 Levels of MGO correlate with various manuka honey-grading schemes, with the unique manuka factor (UMF) scheme being the most widely used. For instance, UMF 15+ has ≥ 514 mg/kg of MGO.11 While higher UMF levels are often associated with improved antibacterial properties, some studies10,11 suggest that UMF does not always correlate directly with antibacterial activity.
Manuka honey is the most commonly used type of honey in FDA-approved medical-grade honey (MGH) products.12 Medical-grade honey is required to undergo sterilization by gamma irradiation and meet strict standards including a stipulated antibacterial activity for its use in wound care,13 likely minimizing the presence of pathogenic microorganisms that could limit its antibacterial activities. Hence, MGH has historically been thought to have superior antibacterial activity.
Currently, there are many types of MGH and non-MGH types available on the market. Despite the vast amount of literature comparing different types of honey and their antibacterial effects in human wound cultures,8,14–19 there is limited information available in the veterinary literature. Medical-grade honey has been shown to increase the healing rates of wounds in human studies.20–22 Interestingly, despite manuka honey’s preexisting popularity as a therapeutic agent for wounds, various studies15,23,24 have shown that polyfloral honey may exhibit similar antibacterial properties. To the authors’ knowledge, there is limited information regarding the efficacy of different types of honey, specifically in the comparison of MGH and non–medical-grade honey (non-MGH) on wound cultures in dogs and cats.
Commonly reported bacterial isolates from dog and cat wounds include Staphylococcus pseudintermedius, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa.25,26 Wounds contain diverse bacterial populations, with dogs and cats having different wound ecologies from those of humans.25,27,28 However, antibacterial resistance continues to be a global health concern, with companion animals potentially serving as reservoirs in the transmission of antibacterial resistance to humans.29 A recent report25 highlighted a high prevalence of multidrug-resistant bacterial strains in open wounds of dogs and cats, indicating a need for alternative therapies beyond antimicrobials.
In veterinary medicine, finances may be a limiting factor in providing care for patients, making cost-effective treatment options preferable.30 Non–medical-grade honey types are more easily accessible and cost effective in comparison to MGH,31 making it a more practical option in the management of certain cases. Protocols for honey use in wound management are varied, ranging from the use of MGH to commercially sourced non-MGH.32 It is therefore important to determine if the efficacy of MGH is superior to non-MGH against common bacterial isolates found in wounds of dogs and cats. The objective of our study was therefore to compare the antibacterial activities of different types of honey against these common bacterial isolates found in dog and cat wound cultures. Our hypothesis was that MGH would have superior antibacterial activity in comparison to non-MGH types.
Methods
The study protocol was reviewed and approved by the Auburn University Institutional Biosafety Committee.
Different types of honey and bacterial strains
Four types of honey were used including MGH derived from manuka bush or manuka honey (Medihoney Gel), a non–medical-grade manuka honey (Wedderspoon), a commercially sourced non-MGH (Great Value Clover Honey), and a locally sourced non-MGH (AU-Bees Honey).
Four bacterial cultures, supplied by Auburn University Bacteriology Laboratory, were used including Escherichia coli, Staphylococcus pseudintermedius, Enterococcus faecalis, and Pseudomonas aeruginosa. These pathogens were obtained from wounds cultured from clinical patients at the Auburn University Bailey Small Animal Teaching Hospital. Additionally, E coli ATCC 25922 was obtained as a reference strain. Bacterial cultures were adjusted to be equivalent to optical density at 600 nm of 0.132, which is equal to 0.5 McFarland (1 to 5 X 108 CFU/mL).33 The bacterial cultures were further diluted with cation-adjusted Mueller-Hilton broth (CAMHB) at a ratio of 1:150 vol/vol to achieve a final working concentration of 1.5 X 106 CFU/mL.33
Minimum inhibitory concentrations and minimum bactericidal concentrations
The honey samples were diluted with CAMHB to achieve a total volume of 3 mL and inoculated with 1.5 mL of bacteria, achieving the following working concentrations of honey (vol/vol): 6.5%, 9.8%, 14.7%, 22%, 16.7%, 33.3%, 40%, 46.7%, 53.3%, and 66.7%. The honey solutions were obtained by measuring the respective weights, which correlate with the appropriate volume of honey. All experiments were performed in duplicates. Honey dilutions were mixed using a vortex (Thermo Scientific) until a uniform solution was obtained. All test tubes were then incubated for 24 hours at 37 °C. For different types of honey, a negative and positive control were included. These consisted of 3 mL of honey diluted with 1.5 mL CAMHB (negative control) and 3 mL of honey inoculated with 1.5 mL of bacterial culture (positive control). All test and control tubes were then incubated for 24 hours at 37 °C.
The above methods were used to calculate the MICs. Further, to determine the minimum bactericidal concentration (MBC), all samples from MIC experiments postincubation were subcultured onto Mueller Hinton agar plates and further incubated at 37 °C for 24 hours. For each type of honey, the lowest concentration of honey without visible bacterial growth on the agar plates was then determined as the MBC.
Statistical analysis
The results for MBC are presented descriptively. The percent growth inhibition of each bacterium was plotted for each type of honey and concentration. Honey concentration was categorized as low (6.50% to 14.67%), medium (14.67% to 33.3%), and high (33.3% to 53.33%) based on data distribution. Data distribution was assessed, and normality was determined by plotting the main outcome variable (percent growth inhibition). Generalized linear regression modeling was performed for each bacteria type and honey concentration category separately using percent growth inhibition as the main outcome variable and type of honey as the main categorical explanatory variable. Further, post hoc pairwise comparison was performed using Tukey honestly significant difference with Bonferroni correction to compare differences among different types of honey. Statistical analyses were performed using RStudio, version 4.3.1 (2023-06-16 ucrt; The R Foundation). All significance levels were set to P ≤ .05.
Results
Percent growth inhibition was dependent on concentration for all different types of honey (Figures 1–4; Supplementary Figure S1), with MGH having the most consistent bacterial growth inhibition. MGH was most effective against S pseudintermedius, in which 9.8% (vol/vol) was required to achieve MIC at 90% (MIC90), whereas to achieve MIC90 for P aeruginosa, E faecalis, and E coli, a 14.67% (vol/vol) of MGH honey was necessary. For all different types of honey, the most effective concentration to achieve MIC90 for ATCC E coli was 33.33% (vol/vol). Overall, at lower concentrations, MGH exhibited higher bacterial growth inhibition compared to other types of honey, except for ATCC E coli for which MGH’s MIC90 was comparable to that of other types of honey. Furthermore, at higher concentrations of honey (> 40%), all different types of honey reached MIC90. Given the consistency of commercially sourced non-MGH, it was difficult to achieve a homogenized solution and a measurement of optical density at 600 nm. Therefore, commercially sourced non-MGH is only included in MBC results.
Percent growth inhibition of Staphylococcus pseudintermedius among different honey types. A—Percent growth inhibition of bacteria across honey concentrations. B—Differences in percent growth inhibition among honey types for low, medium, and high concentrations of honey. Percent growth inhibition results for clover honey are affected by its viscosity, which impacts the accuracy of optical density measurement. Therefore, statistical comparisons did not include this clover honey (B). Commercial = Commercially sourced non–medical-grade honey (non-MGH). Local = Locally sourced non-MGH. Manuka = Non–medical-grade manuka honey. MGH = Medical-grade honey. MIC90 = MIC at 90%. *P < .05
Citation: American Journal of Veterinary Research 85, 12; 10.2460/ajvr.24.07.0188
Percent growth inhibition of Pseudomonas aeruginosa among different honey types. A—Percent growth inhibition of bacteria across honey concentrations. B—Differences in percent growth inhibition among honey types for low, medium, and high concentrations of honey. Percent growth inhibition results for clover honey are affected by its viscosity, which impacts the accuracy of optical density measurement. Therefore, statistical comparisons did not include this clover honey (B).
Citation: American Journal of Veterinary Research 85, 12; 10.2460/ajvr.24.07.0188
Percent growth inhibition of Enterococcus faecalis among different honey types. A—Percent growth inhibition of bacteria across honey concentrations. B—Differences in percent growth inhibition among honey types for low, medium, and high concentrations of honey. Percent growth inhibition results for clover honey are affected by its viscosity, which impacts the accuracy of optical density measurement. Therefore, statistical comparisons did not include this clover honey (B). ***P < .05.
Citation: American Journal of Veterinary Research 85, 12; 10.2460/ajvr.24.07.0188
Percent growth inhibition of Escherichia coli among different honey types. A—Percent growth inhibition of bacteria across honey concentrations. B—Differences in percent growth inhibition among honey types for low, medium, and high concentrations of honey. Percent growth inhibition results for clover honey are affected by its viscosity, which impacts the accuracy of optical density measurement. Therefore, statistical comparisons did not include this clover honey (B). *P < .05.
Citation: American Journal of Veterinary Research 85, 12; 10.2460/ajvr.24.07.0188
No significant differences were found in the bacterial growth inhibition among different types of honey in low concentrations (6.5% to 14.67%) using a multivariable regression model (Figures 1–4; Table 1). However, significant differences were found in bacterial growth inhibition in the medium concentration (14.67% to 33.33%) honey group.
Multivariable analysis to determine the effect of honey concentration (low, medium, and high) on bacterial growth inhibition for each honey type and for each of the 5 bacterial strains.
| Low concentration (6.50% to 14.67%) | Medium concentration (14.67% to 33.33%) | High concentration (33.3% to 53.33%) | ||||||
|---|---|---|---|---|---|---|---|---|
| Bacteria | Honey type | Reference honey type | Estimate (95% CI) | P | Estimate (95% CI) | P | Estimate (95% CI) | P |
| SP | Non–medical-grade manuka honey | Locally sourced non-MGH | −7 (−108 to 92) | 1 | 46 (15 to 77) | .001* | 11 (0.83 to 21) | .03* |
| MGH | Locally sourced non-MGH | 27 (−73 to 127) | 1 | 60 (29 to 91) | < .001* | 9 (−0.88 to 19) | .09 | |
| MGH | Non–medical-grade manuka honey | 34 (−65 to 135) | 1 | 14 (−16 to 45) | .80 | −1 (−12 to 8) | 1 | |
| PA | Non–medical-grade manuka honey | Locally sourced non-MGH | −6 (−71 to 58) | 1 | −7 (−38 to 24) | 1 | −2 (−6 to 1) | .3 |
| MGH | Locally sourced non-MGH | −5 (−71 to 59) | 1 | 18 (−12 to 50) | .48 | −1 (−5 to 1) | .61 | |
| MGH | Non–medical-grade manuka honey | 0.86 (−64 to 66) | 1 | 25 (−5 to 57) | .16 | 0.59 (−3 to 4) | 1 | |
| EF | Non–medical-grade manuka honey | Locally sourced non-MGH | −2 (−80 to 75) | 1 | 29 (−30 to 89) | .74 | 8 (−5 to 22) | .5 |
| MGH | Locally sourced non-MGH | −5 (−83 to 71) | 1 | 101 (41 to 161) | < .001* | 7 (−6 to 21) | .57 | |
| MGH | Non–medical-grade manuka honey | −3 (−81 to 74) | 1 | 71 (11 to 132) | .01* | −0.43 (−14 to 13) | 1 | |
| EC | Non–medical-grade manuka honey | Locally sourced non-MGH | −4 (−55 to 46) | 1 | 4.78 (−33 to 42) | 1 | −2 (8 to 2) | .63 |
| MGH | Locally sourced non-MGH | 7.79 (−43 to 58) | 1 | 41.43 (3.32 to 79) | .03* | −4 (−9 to 1) | .16 | |
| MGH | Non–medical-grade manuka honey | 12.52 (−38 to 63) | 1 | 36.65 (−1 to 74) | .07 | −1 (−6 to 3) | 1 | |
| ATCC EC | Non–medical-grade manuka honey | Locally sourced non-MGH | −11.63 (−33 to 10) | .62 | −1.53 (−25 to 22) | 1 | −2 (−6 to 0.33) | .10 |
| MGH | Locally sourced non-MGH | −10 (−32 to 11) | .78 | 7 (−16 to 32) | 1 | −3 (−6 to 0.04) | .06 | |
| MGH | Non–medical-grade manuka honey | 1.24 (−20 to 22) | 1 | 9 (−15 to 33) | 1 | −0.28 (−3 to 2) | 1 | |
ATCC EC = ATCC Escherichia coli. EC = Escherichia coli. EF = Enterococcus faecalis. MGH = Medical-grade honey. PA = Pseudomonas aeruginosa. SP = Staphylococcus pseudintermedius.
*P < .05.
The growth inhibition of S pseudintermedius by non–medical-grade manuka honey and MGH was significantly higher compared to that of the locally sourced and commercially sourced non-MGH types. For instance, growth inhibition of S pseudintermedius by non–medical-grade manuka honey treatment was significantly higher by 46.25% (95% CI, 15.23 to 77.27) than that of the local honey (P = .001). Similarly, growth inhibition of S pseudintermedius by MGH treatment was significantly higher by 60.89% (95% CI, 29.87 to 91.91) than that of local honey (P < .001). Meanwhile, growth inhibition of E coli by MGH was significantly higher by 41.43% (95% CI, 3.32 to 79.55) than that of the local honey (P = .03). Whereas for E faecalis, growth inhibition by MGH was significantly higher by 101.47% (95% CI, 41.26 to 161.68) than that of local honey (P < .001). At high concentrations (33.3% to 53.33%), non–medical-grade manuka honey treatment had a significantly higher growth inhibition of 11.25% (95% CI, 0.83 to 21.68) against S pseudintermedius, as compared to that of local honey (P = .03).
The MBC of each type of honey against each bacterial species was identified (Table 2). In general, MGH had the highest bactericidal activity against all bacterial species, apart from pathogenic E coli, against which non–medical-grade manuka honey has a similar MBC. Medical-grade honey was more bactericidal compared to the other types of honey against S pseudintermedius, in which a concentration of 33.3% was sufficient to prevent bacterial growth, compared to 46.7% of the other types of honey. Likewise, MGH was superior against E faecalis, in which a concentration of 46.7% was sufficient to prevent bacterial growth, compared to ≥ 66.7% of the other types of honey. Medical-grade honey was also more bactericidal against P aeruginosa, in which a concentration of 33.3% was sufficient to prevent bacterial growth, compared to 40% of the other types of honey. For pathogenic E coli, MGH and non–medical-grade manuka honey were more bactericidal compared to the other types of honey, both having an MBC of 33.3%, compared to 40% and 53.3% of commercially sourced and locally sourced non-MGH, respectively. For ATCC E coli, MGH, non–medical-grade manuka honey, and commercially sourced non-MGH had an MBC of 33.3%, whereas local honey had an MBC of 40%.
Minimum bactericidal concentrations of each honey type against each bacterial species.
| MBC (% vol/vol) | |||||
|---|---|---|---|---|---|
| Honey types | ATCC EC | EC | SP | EF | PA |
| MGH | 33.3 | 33.3 | 33.3 | 46.7 | 33.3 |
| Non–medical-grade manuka honey | 33.3 | 33.3 | 46.7 | 66.7 | 40 |
| Commercially sourced non-MGH | 33.3 | 40 | 46.7 | > 66.7 | 40 |
| Locally sourced non-MGH | 40 | 53.3 | 46.7 | > 66.7 | 40 |
Minimum bactericidal concentration (MBC) in percent volume/volume of each honey type against each bacterial isolate.
Discussion
Based on our findings, MGH exhibited the lowest MBC against S pseudintermedius, E faecalis, and P aeruginosa. Medical-grade honey also had the lowest MIC90 and the most consistent bacterial growth inhibition for all bacteria tested in this study. There was a significant difference between the bacterial growth inhibition of MGH and locally sourced non-MGH in medium concentrations, as compared to that in high concentrations. This correlates in proportion with the MIC90 of MGH and locally sourced non-MGH, wherein lower concentrations of MGH were sufficient to inhibit bacterial growth as compared to that of locally sourced non-MGH. Therefore, MGH was found to be more efficacious than other types of honey against common bacterial isolates found in wounds of dogs and cats. Although MGH’s MIC90 was comparable to that of other types of honey for ATCC E coli, this strain is nonpathogenic and provides a reference for antimicrobial susceptibility.
Non–medical-grade manuka honey had the second lowest MIC90 and MBC values compared with all types of honey. Notably, many veterinary practices use non–medical-grade manuka honey for topical wound therapy due to its purported antimicrobial effects in human studies.35 Medical-grade honey and non–medical-grade manuka honey are typically costlier in comparison to commercial and local non-MGH types.36 Given that cost is often a limiting factor for care in veterinary patients, our goal was to determine how commercially and locally sourced non-MGH compared to that of MGH and non–medical-grade manuka honey. In our study, all types of honey tested exhibited antibacterial activity at some level (Figures 1–4; Supplementary Figure S1).
Commercially sourced non-MGH and locally sourced non-MGH were not inferior to manuka honey against certain bacterial isolates; therefore, knowing the specific wound ecology may be important in selecting a specific type of honey for topical wound therapy. Ideally, cultures could be obtained from multiple different sources and etiologies; however, this would significantly increase the cost and time of the study. For instance, we found that the bacterial growth inhibition activity of manuka honey was significantly higher in medium and high concentrations than locally sourced non-MGH against S pseudintermedius. For all other bacteria, the growth inhibition activity of manuka honey was comparable to other types of honey. For bactericidal properties, manuka honey was more efficacious against E coli and E faecalis (Table 2). However, the bactericidal activity of manuka honey was similar to locally sourced non-MGH for S pseudintermedius and P aeruginosa. It is important to note that part of the efficacy of manuka honey depends on its UMF grade.10,11 The non–medical-grade manuka honey brand that was used in our study does not specify a UMF. Hence, our study cannot rule out that if a different manuka honey brand with a different UMF grade was used, the results may be different. In this study, commercially sourced non-MGH exhibited similar efficacy to non–medical-grade manuka honey against S pseudintermedius and P aeruginosa. These findings further demonstrate the variability of honey against specific pathogens
Interestingly, our study showed that the types of honey used inhibited the growth of E faecalis, as compared to other studies reporting that the growth of E faecalis was not inhibited by honey.37 This difference may be attributed to the significant variety of honey types used, including its origin and source such as Australian manuka honey or Chinese buckwheat honey, or more likely, the presence of multispecies biofilms noted in other studies, which reflects a typical wound environment. Additionally, although honey has antimicrobial properties against both gram-positive and gram-negative bacteria, some studies37,38 have shown that honey is more susceptible to gram-negative bacteria. As corroborated in our study, the gram-positive bacteria including S pseudintermedius and E faecalis had the highest MBCs across the types of honey studied, as compared to those of the gram-negative bacteria E coli and P aeruginosa.
Overall, locally sourced non-MGH had the lowest bacterial inhibitory activity against all tested bacteria; however, at higher concentrations, it exhibited MIC90 against all tested bacteria except E coli. These findings may be attributed to the locally sourced polyfloral origins. For instance, the known important sources of nectar for local Auburn honey bees include flowers such as clovers, Chinese tallows, and tulips.39 Monofloral kinds of honey, such as manuka honey, and their polyphenolic characteristics are highly correlated with their strong antibacterial properties.40,41 However, some studies19,23 show that polyfloral honey can exhibit robust antibacterial properties. Interestingly, local honey has been thought to exhibit better antibacterial activity against certain local pathogens as a protective mechanism for the honey bee immune system,42 potentially being more efficacious against the bacteria of locally acquired wounds. Nonetheless, we found that its bactericidal efficacy only against S pseudintermedius and P aeruginosa is equivalent to that of manuka honey. Given that our hospital treats patients from various geographical locations, it is possible that the bacterial isolates used in this study were acquired distant from our local environment; therefore, the locally sourced non-MGH may have been less efficacious against these pathogens.
In our study, the commercially sourced non-MGH was noted to be more viscous, making it difficult to obtain a homogenous solution for optical density measurements. This resulted in inconsistencies in its growth curve, complicating the interpretation of its percent growth inhibition results. To circumvent this issue and improve the reliability of our findings, we focused on MBC experiments to evaluate the antibacterial efficacy of commercially sourced non-MGH. Minimum bactericidal concentration experiments rely on the plating of bacterial culture posttreatment, eliminating the need for optical density measurements. Nonetheless, a preliminary or pilot study would ideally have been conducted before starting the investigation, allowing us to better assess our materials and adapt to any issues accordingly.
Honey is an important topical therapy in an era of antimicrobial resistance in both human and veterinary medicine, especially since wounds often harbor bacteria that are resistant to most first-line antibacterials. Acquired antimicrobial resistance against honey has not yet been discovered in vivo, although a recent in vitro study43 showed that suboptimal concentrations of manuka honey did not prevent the growth of resistant bacterial wound pathogens. This suggests that optimal concentrations of honey at the wound-dressing interface are integral in inhibiting bacterial growth. In our study, all honey was effective at inhibiting 90% bacterial growth at concentrations of 33.33% or more or reached MIC90 at higher concentrations (> 40%), which is often lower than the amount of honey typically applied in an infected wound even after accounting for dilution from wound exudation.43 Moreover, most MGH and manuka honey products have a concentration of at least 80%.43 Based on this information, it is likely that the other types of honey would potentially be efficacious against the common bacterial isolates found in the wounds of dogs and cats. Nonetheless, due to the widely reported use of medications to treat beehive diseases, antibiotic residues have been found in some honey samples.44 In our study, the honey types were not tested for antibiotic residues or known to be treated apart from the MGH. The presence of antibiotic residues may conflate the antimicrobial activities of each honey type.
This study had several limitations. First, natural honey samples, or non-MGH types, are known to have their own microbial flora, which may include aerobic and anaerobic bacteria, coliforms, clostridia, yeast, and/or fungi,14 whereas MGH is a sterilized product free of contamination. The influence of honey’s microbiome on its unique antibacterial activities has not yet been described. It is possible that the microbiomes of the non-MGH types could have affected our spectrophotometric readings, as growth of any live organisms can influence turbidity.45 Apart from MGH, all other types of honey used were nonsterile; therefore, it was impossible to rule out secondary contamination from the honey’s unique microbiome. Nevertheless, none of the negative control groups exhibited any visible bacterial growth after plating. Although investigation into the microbial flora of each honey type is warranted, our study aimed to emulate a clinical setting, in which sterilized MGH products may not be readily accessible. In the future, non-MGH honey types could be tested for bacterial spores, as these may likely interfere with study results, thereby affecting our recommendation for clinical use. Honey is a highly variable product, owing to its combination of characteristics including bacterial flora and the unique UMF grade. Hence, the comparison of only 4 types of honey in our study is limited in scope. As with honey types, bacterial species can also be significantly variable.
Our second limitation was in obtaining MIC readings by using a spectrophotometer. Spectrophotometric readings rely on the number of volatile compounds,46–48 which differs with each type of honey, as each honey is comprised of different constituents of minerals, peptides, and amino acids.46 Although spectrophotometry is known to be reliable at evaluating bacterial growth, most studies evaluating MICs using spectrophotometry have been conducted using a single honey type,49 as opposed to a comparison of different types of honey. In our study, the types of honey that we used had varying viscosities, which further impacted the optical density readings and thus the MIC. Medical-grade honey and manuka honey were much better at having a homogenized solution postdilution. This would likely explain, in part, why MGH and manuka honey had more consistent MIC readings. However, our results are supported by MBC experiments, which do not rely on spectrophotometry and circumvent the challenges associated with optical density measurements.
Finally, our in vitro study was conducted in a controlled laboratory setting without accounting for wound characteristics. For instance, honey’s osmotic properties enhance the moisture balance of the wound, preventing further bacterial colonization and allowing for autolytic debridement of damaged tissue.50 Furthermore, infected wounds are often polymicrobial in nature25,26; hence, it is important to assess the efficacy of honey against multiple bacteria. Mixing the different types of honey with the bacterial isolates would also make the contact extremely effective, which may be unrealistically efficient compared to that in real-life clinical situations. There are also limited studies evaluating the synergistic effects of topical honey and antibiotics against specific bacterial species such as S pseudintermedius.51 Further investigation is required to determine the antibacterial effect of honey in vivo, as well as to determine if specific combinations of honey and antibiotics may improve wound healing in dogs and cats. Additionally, a recent study52 has also shown that in horses, intralesional instillation of MGH before wound or incision closure can decrease the occurrences of infection and wound dehiscence. This is a potential area for further studies of honey use in cats and dogs.
In conclusion, the MGH used in our study displayed the greatest antibacterial activity against common wound pathogens and should be considered over other types of honey for wound management in cats and dogs. In our study, we found that locally sourced and commercially sourced non-MGH displayed similar antibacterial properties to that of manuka honey against certain bacterial strains. Therefore, commercially sourced and locally sourced non-MGH may have the potential to act as cost-effective alternatives to MGH and manuka honey against certain wound infections; however, more studies are required to substantiate their antibacterial efficacy. Furthermore, there are different types of MGH available, including non–manuka-based MGH,12 whose antibacterial properties could be evaluated and compared in future studies.
Supplementary Materials
Supplementary materials are posted online at the journal website: avmajournals.avma.org.
Acknowledgments
None reported.
Disclosures
The authors have nothing to disclose. No AI-assisted technologies were used in the generation of this manuscript.
Funding
The authors have nothing to disclose.
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