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Evidence and Clinical Applications of Natural Products in Veterinary Medicine: A Systematic Review of Clinoptilolite, Ozone Therapy, Propolis, and Phytotherapy
by
, , ,
Dražen Đuričić
1,*
,
Ivona Žura Žaja
1
,
Alicja Kowalczyk
2, 
Ksenija Vlahović
3,
Hrvoje Valpotić
4
,
Mislav Kovačić
5,
Marko Pećin
6 and
Marko Samardžija
7 1
Department of Physiology and Radiobiology, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
2
Faculty of Biology and Animal Science, University of Environmental and Life Sciences, University of Wroclaw, Chelmonskiego 38C, 51-630 Wroclaw, Poland
3
Department of Biology, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
4
Department of Animal Nutrition and Dietetics, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
5
Department of Biology, University of Osijek, Ulica cara Hadrijana 8/A 31000 Osijek, Croatia
6
Clinic for Surgery, Orthopedics and Ophthalmology, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, 10000 Zagreb, Croatia
7
Clinic of Reproduction and Obstetrics, Faculty of Veterinary Medicine, University of Zagreb,Heinzelova 55, 10000 Zagreb, Croatia
*
Author to whom correspondence should be addressed.
Vet. Sci. 2026, 13(5), 483; https://doi.org/10.3390/vetsci13050483 (registering DOI)
Submission received: 9 April 2026
/
Revised: 4 May 2026
/
Accepted: 7 May 2026
/
Published: 16 May 2026
(This article belongs to the Special Issue Natural Products in Veterinary Therapy: Evidence, Applications, and Integrative Approaches to Improve Animal Health and Welfare)
Simple Summary
This study explores natural ways to keep animals healthy while reducing antibiotic use. Researchers examined four approaches: clinoptilolite, a mineral that supports digestion and detoxification; ozone therapy, which can fight infections and boost immunity; propolis from bees, known for its antimicrobial and antioxidant effects; and plant-based treatments that can replace antibiotic growth promoters, especially in poultry and pigs. Although the studies varied in quality and more rigorous trials are needed, these natural products show real potential to improve animal health safely. Using these approaches may also provide broader benefits for environmental sustainability and public health. Their integration into veterinary practice could contribute to reduced antibiotic use, improved farm sustainability, and support for animal health while minimizing potential ecological impacts.
Abstract
The increasing demand for sustainable and antibiotic-free veterinary practices has stimulated interest in natural products such as clinoptilolite, ozone therapy, bee-derived products, and phytotherapy. This systematic review evaluates evidence from 2010 to 2026 regarding their clinical efficacy and mechanisms of action. A comprehensive literature search was conducted across PubMed, Scopus, Web of Science, CAB Abstracts, Google Scholar, and regional veterinary journals using predefined keywords related to natural alternatives in veterinary medicine. These studies were critically appraised due to frequent methodological limitations, including lack of randomization and control groups. From 1124 identified records, 842 studies were screened after duplicates were removed, 214 full-text articles were assessed for eligibility. A total of 96 studies meeting the predefined inclusion criteria were included in the final analysis. Clinoptilolite consistently improved gastrointestinal health and detoxification in livestock. Ozone therapy demonstrated broad antimicrobial and immunomodulatory effects, though standardized protocols are lacking. Bee-derived products, especially propolis exhibited strong antimicrobial and antioxidant properties, with variable clinical translation. Phytotherapy emerged as a promising alternative to antibiotic growth promoters. Overall, the available evidence suggests that these natural interventions may serve as promising adjuncts in veterinary practice; however, their current application is constrained by heterogeneity, limited randomized controlled trials, and lack of standardized protocols. Consequently, they should be considered supportive rather than definitive alternatives to conventional therapies. Further well-designed, standardized clinical studies are required to confirm efficacy, optimize application, and support evidence-based integration into modern veterinary medicine.
