Uganda poultry botanical study flags heavy metal concerns

A new study on indigenous poultry production in Central Uganda suggests that not all traditional botanicals are equally safe as feed additives. Researchers assessed the nutritional, antinutritional, and heavy metal profiles of Capsicum frutescens, Cannabis sativa, and Nicotiana tabacum, three plants used by smallholder farmers in ethnopoultry practice, and concluded that C. frutescens was the safest option for feed use because N. tabacum and C. sativa exceeded FAO/WHO heavy metal safety limits. (fao.org)

The finding lands in a setting where ethnoveterinary medicine remains deeply embedded in Ugandan livestock care. A recent review in the Journal of Ethnopharmacology identified 245 plant species used in Ugandan ethnoveterinary practice and noted that most have not been adequately evaluated for efficacy, safety, or toxicity. Separate field research from Buikwe district in Central Uganda documented the use of Capsicum frutescens, Nicotiana tabacum, and Cannabis sativa in chicken health management, underscoring that these botanicals are not fringe remedies but part of routine practice in some communities. (sciencedirect.com)

That background helps explain why the new paper matters beyond descriptive ethnobotany. The issue is no longer just whether these plants are available or culturally accepted, but whether they can be used without introducing avoidable toxicological risk into poultry systems. Codex, through the FAO/WHO framework, maintains contaminant standards and guidance for food and feed because environmental contaminants, including metals, can enter the chain during production and handling. (fao.org)

The broader toxicology literature supports that concern. Reviews of heavy metal exposure in poultry describe cadmium, lead, arsenic, and mercury as persistent hazards that can enter birds through water, fodder, and feed, then accumulate in organs such as the liver and kidneys. Those exposures are associated with metabolic, structural, and reproductive harm in birds, and they also raise food-safety questions when contamination moves into edible products. Ugandan researchers have already flagged heavy metal exposure as a concern in poultry-related foods, including eggs. (frontiersin.org)

There’s also reason to be especially cautious with some of the plants highlighted in the study. Tobacco has a documented capacity to accumulate heavy metals, and published analyses of tobacco leaves from East Africa have reported measurable contamination with metals of concern. More broadly, reviews of medicinal and feed plants note that contamination can reflect soil conditions, irrigation water, agrochemical use, atmospheric deposition, and post-harvest handling, meaning risk may vary substantially by source and geography. (pmc.ncbi.nlm.nih.gov)

Expert reaction specific to this paper appears limited so far, but the wider Ugandan literature points in the same direction: traditional plant remedies are widely used, yet safety data lag behind practice. The 2026 review of Ugandan ethnoveterinary botanicals explicitly concluded that most species in use have not been scientifically evaluated for toxicity, while the Buikwe poultry study found farmers commonly struggle with dose determination and preservation of remedies. Taken together, that suggests the new paper is part of a larger shift from documenting indigenous knowledge to testing it against modern feed-safety standards. (sciencedirect.com)

Why it matters: For veterinarians, poultry advisers, and feed professionals, the practical takeaway is that phytogenic or ethnoveterinary additives shouldn’t be treated as inherently low-risk. If a botanical shows promise nutritionally but carries heavy metal burdens above accepted limits, its use could undermine flock health, compromise product safety, and expose pet parents and consumers to avoidable risk through eggs or meat. The study also highlights a familiar implementation gap: promising local solutions need standardized sourcing, contaminant testing, and dosing guidance before they can be responsibly recommended. (frontiersin.org)

What to watch: The next step is likely validation work, including source-to-source variability, inclusion-rate studies, and residue tracking in poultry products. If those data hold, Capsicum frutescens could gain traction as a safer ethnobotanical feed additive, while Cannabis sativa and Nicotiana tabacum may face closer scrutiny unless growers and formulators can show contaminant control at the farm and supply-chain level. That’s an inference based on current feed-safety frameworks and the direction of the Ugandan ethnoveterinary literature. (fao.org)