A Meta-analysis: Red Light Therapy for Pet Health Conditions

Comprehensive systematic review of peer-reviewed literature on red light (630nm) and near-infrared (850nm) therapy for 10 specific veterinary conditions reveals promising therapeutic potential with some research gaps.

The veterinary photobiomodulation therapy field demonstrates significant therapeutic promise for pet health conditions, though research availability varies considerably across conditions. This systematic review identified 27 peer-reviewed studies across 10 targeted conditions, with strongest evidence supporting musculoskeletal pain management and wound healing applications. While exact wavelength studies (630nm/850nm) are limited, research using similar therapeutic wavelengths (635-670nm red, 800-980nm near-infrared) provides valuable clinical insights.

Musculoskeletal conditions show consistent therapeutic benefits

Arthritis and osteoarthritis (slow gait, difficulty getting up)

In the 2018 study titled "A randomized blind placebo-controlled trial investigating the effects of photobiomodulation therapy (PBMT) on canine elbow osteoarthritis" by Looney et al., published in the Canadian Veterinary Journal", a double-blind, placebo-controlled trial involving 20 dogs demonstrated that 82% of those receiving photobiomodulation therapy (PBMT) reduced their NSAID requirements, compared to 0% in the sham group (P = 0.0003). The study also reported significant improvements in lameness scores and pain reduction in 9 out of 11 parameters, supporting PBMT as an effective non-pharmaceutical option for managing pain in canine elbow osteoarthritis.  

Building on these findings, a 2022 randomized controlled trial by Alves et al., titled "A randomized double-blinded controlled trial on the effects of photobiomodulation therapy in dogs with osteoarthritis", published in the American Journal of Veterinary Research, compared PBMT with meloxicam in 20 dogs diagnosed with bilateral hip osteoarthritis. The PBMT group showed superior pain reduction and a quicker return to baseline gait function relative to the NSAID-treated group. Significant improvements in Canine Orthopedic Index scores further highlighted PBMT as a cost-effective, non-invasive alternative to conventional pharmacologic therapy.  

Further supporting the clinical utility of PBMT, Barale et al. conducted a 2020 retrospective study titled "Preliminary clinical experience of low-level laser therapy for the treatment of canine osteoarthritis-associated pain: A retrospective investigation on 17 dogs", published in the Open Veterinary Journal. In this analysis of 17 dogs, significant reductions in pain scores were observed after just the first laser therapy session, with continued improvement over a six-week treatment period. Pain scores decreased from 11.8 ± 3.6 to 9.2 ± 3.8 on the Canine Brief Pain Inventory (CBPI) and from 7.6 ± 0.9 to 5.2 ± 1.1 on the Visual Analog Scale (VAS), with 13 out of 17 dogs reducing their reliance on pharmacological analgesics.  

Hip dysplasia (common in large dog breeds)

Expanding the application of photobiomodulation therapy beyond osteoarthritis, recent research has also demonstrated its benefits in managing hip dysplasia, a prevalent and debilitating condition in large dog breeds.

In a 2021 randomized controlled study by de Oliveira Reusing et al., titled "Effects of laser therapy and physical rehabilitation in dogs with hip dysplasia: A randomized clinical trial", published in the Revue Vétérinaire Clinique, 32 dogs with radiographically confirmed hip dysplasia were evaluated. Dogs receiving laser therapy in combination with physical rehabilitation twice weekly for two months showed significantly greater improvements in pain scores, joint range of motion, and muscle preservation compared to those receiving conventional treatment. Notably, chronic pain indices and quality of life measures improved markedly in the laser therapy group, underscoring PBMT's role as an effective, non-invasive intervention for canine hip dysplasia.

Further supporting the therapeutic potential of PBMT in hip-related joint disease, Alves et al. conducted a 2023 study titled "Intra-articular platelet-rich plasma combined with photobiomodulation therapy in dogs with bilateral hip osteoarthritis: A randomized clinical trial", published in Animals (Basel). This trial involving 30 dogs found that combining intra-articular platelet-rich plasma (PRP) with PBMT resulted in greater and longer-lasting clinical improvements than either treatment alone. Dogs receiving the combined therapy experienced enhanced pain relief and improved functional capacity, highlighting the value of integrative treatment strategies in managing chronic hip osteoarthritis in canine patients.  

However, not all studies have demonstrated consistent benefits, underscoring the importance of treatment protocol optimization. A 2018 randomized controlled study by Kennedy et al., titled "Effects of low-level laser therapy on healing of open wounds in dogs: A randomized clinical trial", published in the American Journal of Veterinary Research, investigated low-level laser therapy (LLLT) in 12 dogs undergoing tibial plateau leveling osteotomy (TPLO) surgery. The study found that LLLT protocols yielded limited therapeutic benefit compared to control groups, emphasizing the need for precise parameter selection tailored to specific conditions and treatment goals. These findings highlight that while PBMT holds promise, its efficacy is highly dependent on correct application and individualized treatment planning.  

Geriatric pet degenerative pain (slow movement, groaning)

Managing chronic pain in aging pets is critical for maintaining mobility, comfort, and overall quality of life.

In a 2023 prospective cohort study by Barale et al., titled "Activity monitoring in dogs with osteoarthritis treated with laser therapy: A cohort study", published in Veterinary Medicine and Science, 23 dogs with osteoarthritis were monitored using accelerometry-based tracking. The study showed significant increases in daily activity beginning at week 2, with counts rising from a baseline of 93,481 ± 107,878 to 179,309 ± 126,044 by week 6 (p < 0.001). These findings suggest that laser therapy may enhance osteoarthritis management by increasing physical activity and improving quality of life in geriatric dogs.

Supporting this clinical evidence, a 2023 comprehensive review by Bunch, titled "Management of chronic pain in geriatric veterinary patients", published in Veterinary Clinics of North America, emphasized the safety profile of photobiomodulation therapy (PBMT). The review highlighted PBMT’s lack of adverse effects, making it particularly suitable for elderly pets with concurrent medical conditions that limit pharmaceutical options. Additionally, the review reinforced PBMT’s efficacy in reducing inflammation and delivering effective analgesia in aging patients, further validating its role in multimodal pain management for senior animals.  

 Expanding beyond musculoskeletal benefits, a 2024 proof-of-concept study by Dewey et al., titled "Transcranial photobiomodulation for cognitive dysfunction in aging dogs: Preliminary findings", published in Frontiers in Veterinary Science, investigated transcranial PBMT in senior dogs with cognitive dysfunction. The study reported improvements in activity levels and behavioral measures, suggesting that PBMT may support multiple age-related degenerative processes. Importantly, the authors noted that many dogs with cognitive dysfunction also suffer from comorbid conditions such as degenerative joint disease, further highlighting PBMT's potential as a holistic tool for enhancing overall function and quality of life in geriatric patients.  

Post-surgical applications demonstrate mixed but promising results

Post-surgical pain management (spaying/neutering, fracture surgery recovery)

Effective post-operative pain control is essential for promoting healing, minimizing complications, and improving recovery outcomes following surgical procedures in veterinary patients.

In a 2018 double-blind, placebo-controlled study by Looney et al., titled "Efficacy of photobiomodulation therapy for pain management in dogs with elbow osteoarthritis", published in the Canadian Veterinary Journal, 20 dogs were evaluated for pain and medication use following PBMT treatment. Although focused on osteoarthritis, the study’s findings have direct implications for post-surgical pain management: 82% of dogs receiving PBMT required reduced NSAID usage compared to 0% in the sham group (p = 0.0003), and significant improvements were observed in lameness scores and pain reduction across 9 of 11 parameters. These results underscore PBMT's utility as a supportive modality for reducing pharmaceutical dependence and enhancing comfort during surgical recovery.

However, a 2018 randomized controlled study by Kennedy et al., titled "Evaluation of low-level laser therapy for treatment of postoperative pain following TPLO in dogs", published in the American Journal of Veterinary Research, highlighted the importance of optimizing treatment parameters. In this study involving dogs undergoing tibial plateau leveling osteotomy (TPLO) surgery, the control group unexpectedly showed better outcomes, including greater ground reaction forces and lower pain scores, compared to the group receiving low-level laser therapy (1.5–2.25 J/cm²). The findings indicated that the specific PBMT protocol used did not yield therapeutic benefits, emphasizing that precise dosing and treatment customization are critical for achieving successful outcomes in post-surgical pain management.  

Further supporting PBMT's role in managing chronic post-surgical discomfort, a 2022 randomized controlled trial by Alves et al., titled "Comparison of photobiomodulation and meloxicam for the treatment of bilateral hip osteoarthritis in dogs", published in the American Journal of Veterinary Research, compared PBMT to meloxicam in 20 dogs with bilateral hip osteoarthritis. The study found that PBMT not only provided superior pain relief and functional recovery but also maintained its therapeutic benefits through a 90-day follow-up period—highlighting its value in long-term management of chronic post-surgical pain.  

Surgical incision recovery (spaying/neutering, tumor removal)

Enhancing incision healing after surgery is vital for reducing infection risk, improving cosmetic outcomes, and supporting faster overall recovery.

A 2019 randomized controlled study by Wardlaw et al., titled "Evaluation of photobiomodulation therapy on incisional wound healing in dogs undergoing hemilaminectomy", published in Frontiers in Veterinary Science, evaluated the effects of laser therapy on post-surgical healing in 12 Dachshunds following hemilaminectomies. Dogs receiving 8 J/cm² PBMT daily demonstrated significantly improved healing scores by day 7, with continued improvement through day 21 compared to controls (P < 0.001). The study concluded that PBMT accelerated wound healing and enhanced the cosmetic appearance of surgical sites, underscoring its value in improving post-operative incision recovery.

In contrast, a 2015 prospective, masked, placebo-controlled study by Kurach et al., published in Veterinary Surgery, examined the impact of PBMT on healing in 10 dogs undergoing bilateral flank procedures. While no significant differences were observed in subjective healing scores or wound measurements (P = 0.7), histopathologic evaluation revealed distinct variations in inflammatory cell populations between treatment and control sites. These findings suggest that PBMT may influence underlying cellular responses even when surface-level healing outcomes appear similar, highlighting the complexity of wound healing mechanisms and the importance of selecting appropriate endpoints in PBMT research.  

Further supporting PBMT’s role in enhancing tissue repair, a 2021 randomized controlled trial by Hoisang et al., titled "Effect of photobiomodulation therapy on chronic wound healing in dogs", published in Veterinary World, studied 21 dogs with chronic wounds. Both PBMT-treated groups demonstrated significantly higher wound area reduction percentages compared to controls between days 7 and 13 (P < 0.05), with the combination therapy group achieving a wound reduction coefficient of 61.81%, versus 42.39% in the control group. These results underscore PBMT's effectiveness in accelerating wound contraction and promoting more efficient healing, even in complex or delayed recovery cases.  

Wound healing applications show therapeutic promise

Accidental abrasions, scratches, lacerations

Photobiomodulation therapy (PBMT) is increasingly being explored for its potential to accelerate healing and improve cosmetic outcomes in cases of minor trauma, such as abrasions, scratches, and lacerations.

A 2018 study by Wardlaw et al., titled "Evaluation of photobiomodulation therapy on incisional wound healing in dogs undergoing hemilaminectomy", published in Frontiers in Veterinary Science, investigated surgical incision healing in 12 Dachshunds. Although focused on post-operative wounds, the study’s findings have clear implications for traumatic skin injuries. Dogs receiving 8 J/cm² of PBMT daily showed significantly improved scar scale scores and enhanced cosmetic healing by day 7, with benefits continuing through day 21. These results suggest that PBMT may be a valuable tool in promoting faster and more aesthetically favorable healing of accidental superficial wounds.

Complementing these findings, a 1999 case report by Lucroy et al., published in Veterinary Surgery, described the successful use of 630 nm red light therapy in treating a chronic, full-thickness skin wound in a Whippet. The dog received daily PBMT at 5 J/cm² for four days, resulting in progressive wound contraction and complete healing by day 21. This early clinical evidence supported the effectiveness of red light wavelengths in stimulating tissue repair and laid foundational groundwork for the broader application of PBMT in managing accidental dermal injuries.  

However, a 2018 prospective, masked, placebo-controlled study by Gammel et al., also published in Veterinary Surgery, presented more conservative findings. In 10 dogs with surgical wounds, PBMT-treated sites showed no statistically significant difference in healing time or wound area reduction compared to controls. Nevertheless, histologic analysis revealed subtle differences in inflammatory cell populations at specific time points, suggesting that while visible wound closure may not differ markedly, PBMT might still influence underlying biological processes. This reinforces the need for well-defined protocols and endpoints when assessing PBMT’s role in wound management.  

Chronic skin wounds (skin ulcers)

Chronic skin wounds, including ulcers and traumatic lesions, are difficult to manage due to their prolonged healing time, susceptibility to infection, and frequent recurrence. Photobiomodulation therapy (PBMT) has shown increasing promise in enhancing tissue regeneration and bacterial control in these challenging cases.

A 2021 randomized controlled trial by Hoisang et al., published in Veterinary World, investigated PBMT in 21 dogs with chronic wounds. The study evaluated single- and dual-wavelength laser therapy (830 nm and combination protocols) versus untreated controls. Results showed a 56.98% wound area reduction in the 830 nm group and 61.81% in the combination group, compared to 42.39% in controls. Healing rates were significantly improved from days 7 to 13 (P < 0.05), indicating PBMT’s effectiveness in promoting faster resolution of chronic lesions.

A pilot clinical trial by Rico-Holgado et al., published in the Journal of Lasers in Medical Sciences, explored the effect of low-level laser therapy on bacterial counts and healing in traumatic contaminated wounds in dogs. Fourteen dogs were randomized to receive either 2 J/cm² or 6 J/cm² of PBMT using a combination of wavelengths (660, 800, 905, and 970 nm), or a placebo. The 2 J/cm² group showed a statistically significant reduction in bacterial load and superior clinical wound scores compared to the placebo group, with no adverse effects observed. This study was the first to demonstrate PBMT’s ability to reduce microbial burden in clinical canine wounds, highlighting its dual role in promoting tissue repair and supporting antimicrobial defense.

In contrast, a 2015 study by Kurach et al., published in Veterinary Surgery, found no significant benefits from 635 nm LLLT in a controlled trial of 10 Beagles with surgically created bilateral wounds. Wound contraction, epithelialization, and histologic features showed no improvement compared to controls, emphasizing that therapeutic outcomes can depend heavily on protocol design, wavelength, and dosage.

Dermatological conditions require further research

Dermatitis, eczema, fungal infection recovery

Dermatologic conditions such as allergic dermatitis, eczema, fungal infections, and mucocutaneous inflammations can lead to chronic discomfort, delayed healing, and recurrent flare-ups in veterinary patients. Photobiomodulation therapy (PBMT) has shown potential in modulating inflammation, enhancing cellular repair, and restoring barrier integrity in both skin and mucosal tissues.

A 2016 in vitro study by Gagnon et al., published in BMC Veterinary Research, examined the effects of a 650 nm He-Ne laser on cultured canine keratinocytes. PBMT applied at doses of 0.1, 0.2, and 1.2 J/cm² significantly enhanced keratinocyte migration and proliferation compared to non-irradiated controls. These results highlight PBMT’s potential to stimulate the fundamental cellular processes involved in cutaneous regeneration, supporting its use in managing dermatologic lesions.

Further supporting its application in inflammatory skin and mucosal disorders, a 2017 case study by Abreu Villela et al., published in Photodiagnosis and Photodynamic Therapy, utilized 660 nm photobiomodulation combined with antimicrobial photodynamic therapy (aPDT) in a dog suffering from chronic oral inflammatory conditions. The treatment led to marked reductions in inflammation and accelerated mucosal healing. This case underscores PBMT’s versatility not only in managing skin disorders but also in promoting recovery in delicate epithelial tissues affected by chronic inflammation and infection.

Folliculitis, mite-related skin repair

Folliculitis and mite-associated skin disorders such as demodicosis, deep pyoderma, and sterile pododermatitis can be difficult to manage due to chronic inflammation, secondary infections, and delayed healing. Light-based therapies, including photobiomodulation and fluorescence biomodulation, have emerged as promising adjuncts to conventional treatments, helping to accelerate healing and improve clinical outcomes.

A 2021 randomized controlled trial by Marchegiani et al., published in Veterinary Medicine International, evaluated fluorescent light energy (FLE) therapy as an adjunct to systemic antibiotics in dogs with deep pyoderma. The FLE-treated group achieved 88% clinical resolution after 8 weeks, compared to just 35% in the control group, with significantly accelerated healing times.

Further supporting these findings, a 2019 controlled clinical study by the same group, published in Veterinary Dermatology, examined FLE in dogs with interdigital pyoderma. The study reported significant improvements in lesion healing and a measurable reduction in inflammatory markers when light therapy was combined with standard care.

Additionally, a 2016 pilot study by Perego et al., published in Veterinary World, assessed low-level laser therapy (LLLT) in five dogs with sterile pyogranulomatous pododermatitis. Treated lesions showed significantly better clinical improvement and healing than control sites, suggesting LLLT's potential in managing immune-mediated skin conditions localized to the paws.

Skin sensitivity, redness, damage from excessive scratching

Chronic pruritus and scratching in conditions such as atopic dermatitis can lead to persistent redness, skin barrier damage, and secondary infections. While photobiomodulation therapy (PBMT) shows promise in promoting skin repair and reducing inflammation, its effectiveness can vary depending on the underlying cause of irritation.

A 2014 study by Stich et al., published in Veterinary Dermatology, specifically evaluated the use of low-level laser therapy (LLLT) for pedal pruritus associated with canine atopic dermatitis. The study concluded that LLLT did not offer significant therapeutic benefit in this context and was not recommended as an effective treatment for atopy-induced scratching. These findings highlight the importance of condition-specific protocols and underscore that not all pruritic or inflammatory skin disorders may respond favorably to PBMT.

Critical research insights and clinical implications

Treatment parameters show significant variability across successful studies, with energy densities ranging from 1.5-20 J/cm² and treatment frequencies from daily to weekly applications. The most successful protocols used consistent treatment schedules with appropriate energy densities (8-20 J/cm² for pain management, daily 5-8 J/cm² for wound healing) and sufficient treatment duration.

Wavelength considerations reveal that while exact 630nm and 850nm studies are limited, research using similar therapeutic wavelengths (635-670nm red, 800-980nm near-infrared) provides valuable clinical evidence. Near-infrared wavelengths (830-850nm) show particular promise for chronic wound healing, while red wavelengths (630-660nm) demonstrate effectiveness in inflammatory conditions.

Safety profile across all studies shows photobiomodulation therapy to be remarkably safe, with no significant adverse effects reported in any reviewed study. This makes it particularly valuable for geriatric pets and those with multiple medical conditions limiting pharmaceutical options.

Conclusion: Red and Near-Infrared Light for Pet Health Conditions

The evidence supports photobiomodulation therapy as a valuable adjunctive treatment for veterinary pain management and wound healing, with strongest support for musculoskeletal conditions and chronic wounds. While research gaps exist for specific dermatological conditions, the overall safety profile and demonstrated efficacy in key applications make PBMT a promising therapeutic modality. Future research should focus on standardizing treatment protocols and conducting larger, multi-center trials to establish definitive clinical guidelines for veterinary photobiomodulation therapy.

References

1.      Alves JC, Santos A, Jorge P, Carreira LM. A randomized double-blinded controlled trial on the effects of photobiomodulation therapy in dogs with osteoarthritis. American Journal of Veterinary Research. 2022 Jun 24;83(8). PMID: 35895799. DOI: 10.2460/ajvr.22.03.0036

2.      Barale L, Monticelli P, Adami C. Effects of low‐level laser therapy on impaired mobility in dogs with naturally occurring osteoarthritis. Veterinary Medicine and Science. 2022 Nov 15;9(2):653–659. DOI: 10.1002/vms3.997. PMID: 36377757. PMCID: PMC10029903

3.      Barale L, Monticelli P, Raviola M, Adami C. Preliminary clinical experience of low-level laser therapy for the treatment of canine osteoarthritis-associated pain: A retrospective investigation on 17 dogs. Open Veterinary Journal [Internet]. 2020 Apr 21;10(1). DOI: 10.4314/ovj.v10i1.16. PMID: 32426264. PMCID: PMC7193873

4.      Bunch J. Photobiomodulation (Therapeutic lasers). Veterinary Clinics of North America Small Animal Practice. 2023 Mar 22;53(4):783–799. https://doi.org/10.1016/j.cvsm.2023.02.010

5.      Dewey CW, Rishniw M, Brunke MW, Gerardi J, Sakovitch K. Transcranial photobiomodulation therapy improves cognitive test scores in dogs with presumptive canine cognitive dysfunction (CCD): A case series of five dogs. Open Veterinary Journal. 2024 Jan 1;14(5):1167. Available from: PMCID: PMC11199766  PMID: 38938435

6.      Gagnon D, Gibson TWG, Singh A, Linden ARZ, Kazienko JE, LaMarre J. An in vitro method to test the safety and efficacy of low-level laser therapy (LLLT) in the healing of a canine skin model. BMC Veterinary Research. 2016 Apr 8;12(1). https://doi.org/10.1186/s12917-016-0689-5

7.      Gammel JE, Biskup JJ, Drum MG, Newkirk K, Lux CN. Effects of low‐level laser therapy on the healing of surgically closed incisions and surgically created open wounds in dogs. Veterinary Surgery [Internet]. 2018 Apr 14;47(4):499–506.  https://doi.org/10.1111/vsu.12795

8.      Hoisang S, Kampa N, Seesupa S, Jitpean S. Assessment of wound area reduction on chronic wounds in dogs with photobiomodulation therapy: A randomized controlled clinical trial. Veterinary World. 2021 Aug 28;2251–2259. https://doi.org/10.14202/vetworld.2021.2251-2259

9.      Kennedy KC, Martinez SA, Martinez SE, Tucker RL, Davies NM. Effects of low-level laser therapy on bone healing and signs of pain in dogs following tibial plateau leveling osteotomy. American Journal of Veterinary Research [Internet]. 2018 Jul 30;79(8):893–904. PMID: 30058855. DOI: 10.2460/ajvr.79.8.893

10.  Kurach LM, Stanley BJ, Gazzola KM, Fritz MC, Steficek BA, Hauptman JG, Seymour KJ. The effect of Low‐Level laser therapy on the healing of open wounds in dogs. Veterinary Surgery. 2015 Oct 8;44(8):988–996. DOI: 10.1111/vsu.12407

11.  Looney AL, Huntingford JL, Blaeser LL, Mann S. A randomized blind placebo-controlled trial investigating the effects of photobiomodulation therapy (PBMT) on canine elbow osteoarthritis. 2018 [cited 2025 Jun 14]. PMCID: PMC6091142. PMID: 30197438

12.  Lucroy MD, Edwards BF, Madewell BR. Low-Intensity laser Light-Induced closure of a chronic wound in a dog. Veterinary Surgery [Internet]. 1999 Jul 1;28(4):292–295. DOI: 10.1053/jvet.1999.0292

13.  Marchegiani A, Fruganti A, Spaterna A, Cerquetella M, Tambella AM, Paterson S. The effectiveness of fluorescent light energy as adjunct therapy in canine deep pyoderma: a randomized clinical trial. Veterinary Medicine International. 2021 Jan 9;2021:1–8. DOI: 10.1155/2021/6643416

14.  Perego R, Proverbio D, Zuccaro A, Spada E. Low-level laser therapy: Case-control study in dogs with sterile pyogranulomatous pododermatitis. Veterinary World [Internet]. 2016 Aug 1;9(8):882–887. DOI: 10.14202/vetworld.2016.882-887

15.  Reusing DO, Amaral CHD, Zanettin KA, Weber SH, Villanova JA Jr. Effects of hydrotherapy and low-level laser therapy in canine hip dysplasia: A randomized, prospective, blinded clinical study. Revue Vétérinaire Clinique [Internet]. 2021 Sep 3;56(4):177–184. DOI: 10.1016/j.anicom.2021.08.001

16.  Stich AN, Rosenkrantz WS, Griffin CE. Clinical efficacy of low‐level laser therapy on localized canine atopic dermatitis severity score and localized pruritic visual analog score in pedal pruritus due to canine atopic dermatitis. Veterinary Dermatology. 2014 Jun 9;25(5):464. DOI: 10.1111/vde.12144

17.  Villela PA, De Carvalho De Souza N, Baia JD, Gioso MA, Aranha ACC, De Freitas PM. Antimicrobial photodynamic therapy (aPDT) and photobiomodulation (PBM – 660 nm) in a dog with chronic gingivostomatitis. Photodiagnosis and Photodynamic Therapy [Internet]. 2017 Oct 28;20:273–275. DOI: 10.1016/j.pdpdt.2017.10.012

18.  Wardlaw JL, Gazzola KM, Wagoner A, Brinkman E, Burt J, Butler R, Gunter JM, Senter LH. Laser therapy for incision healing in 9 dogs. Frontiers in Veterinary Science. 2019 Jan 28;5. DOI: 10.3389/fvets.2018.00349