The aetiology, prevalence and morbidity of outbreaks of photosensitisation in livestock: A review

Yuchi Chen; Jane C Quinn; Leslie A Weston; Panayiotis Loukopoulos

doi:10.1371/journal.pone.0211625

The aetiology, prevalence and morbidity of outbreaks of photosensitisation in livestock: A review

PLoS One. 2019 Feb 27;14(2):e0211625. doi: 10.1371/journal.pone.0211625. eCollection 2019.

Authors

Yuchi Chen^{1

2}, Jane C Quinn^{1

2}, Leslie A Weston^{2

3}, Panayiotis Loukopoulos^{1

2

4}

Affiliations

¹ School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia.
² Graham Centre for Agricultural Innovation, Charles Sturt University and NSW Department of Primary Industries, Wagga Wagga, New South Wales, Australia.
³ School of Agriculture and Wine Science, Charles Sturt University, Wagga Wagga, New South Wales, Australia.
⁴ Melbourne Veterinary School, University of Melbourne, Werribee, Victoria, Australia.

Abstract

Background: Photosensitisation is a clinical condition occurring in both humans and animals that causes significant injury to affected individuals. In livestock, outbreaks of photosensitisation caused by ingestion of toxic plants are relatively common and can be associated with significant economic loss.

Objectives: The agents that are most commonly implicated in outbreaks of photosensitisation have not been formally investigated on a global scale. To address this question, a systematic review of the literature was undertaken to determine the most common causative agents implicated in outbreaks of photosensitisation in livestock in Australia and globally, as well as the prevalence and morbidity of such outbreaks.

Methods: A systematic database search was conducted to identify peer-reviewed case reports of photosensitisation in livestock published worldwide between 1900 and April 2018. Only case reports with a full abstract in English were included. Non peer-reviewed reports from Australia were also investigated. Case reports were then sorted by plant and animal species, type of photosensitisation by diagnosis, location, morbidity and mortality rate and tabulated for further analysis.

Results: One hundred and sixty-six reports qualified for inclusion in this study. Outbreaks were reported in 20 countries. Australia (20), Brazil (20) and the United States (11) showed the highest number of peer-reviewed photosensitisation case reports from this analysis. Hepatogenous (Type III) photosensitisation was the most frequently reported diagnosis (68.5%) and resulted in higher morbidity. Panicum spp., Brachiaria spp. and Tribulus terrestris were identified as the most common causes of hepatogenous photosensitisation globally.

Conclusions: Hepatogenous photosensitisation in livestock represents a significant risk to livestock production, particularly in Australia, Brazil, and the United States. Management of toxic pastures and common pasture weeds may reduce the economic impact of photosensitisation both at a national and global level.

Publication types

Research Support, Non-U.S. Gov't
Systematic Review

MeSH terms

Animals
Australia / epidemiology
Disease Outbreaks
Humans
Livestock
Morbidity
Photosensitivity Disorders / epidemiology*
Photosensitivity Disorders / mortality*
Prevalence

Grants and funding

Yuchi Chen is supported by a PhD scholarship funded by Graham Centre for Agricultural Innovation and CSU School of Animal and Veterinary Science. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.