A Natural Solution for California's Herds: African Catfish Peptides

California's cattle producers and agricultural communities are all too familiar with the rising challenge of antibiotic resistance, making common bacterial infections harder to treat in livestock. But imagine a future where we could tackle these infections with a natural, powerful alternative. Our research points to just that: antimicrobial peptides (AMPs) found in African catfish.

We're really excited about these peptides because African catfish thrive in pathogen-rich freshwater, naturally producing these robust immune compounds in their skin mucus as a defense. This natural origin makes them highly appealing alternatives to synthetic drugs.

Predicted Safety and Potent Action

One of the most compelling aspects of these AMPs is their predicted safety for mammals. Our initial computer analyses suggest that various catfish AMPs are generally recognized as safe (GRAS). We predict they'll be absorbed in the human intestine without causing liver, brain, or heart toxicity. Furthermore, lab tests on a promising peptide, NACAP-II, confirmed it was non-hemolytic, meaning it didn't damage rabbit red blood cells—a strong indicator of its potential safety for mammalian cells.

Beyond safety, these peptides demonstrate effectiveness against problematic bacteria. One study revealed NACAP-II's strong activity against Extended-Spectrum Beta-Lactamase (ESBL)-producing Escherichia coli—a critical concern for both animal and human health due to its resistance to many common antibiotics. Another peptide, ACAP-IV, also showed antibacterial activity against E. coli and Staphylococcus aureus. We believe these AMPs work by directly disrupting bacterial cell membranes, a mechanism that makes it harder for bacteria to develop resistance compared to how they resist traditional antibiotics.

Asian Citrus Psyllid Distribution and Management: Page

What am I looking for?

The Asian citrus psyllid adult is tiny - the size of an aphid. The wings are brown along the edge, with a clear gap along the back edge. The psyllid feeds with its rear end tilted up at a 45o angle, making the insect appear almost thorn-like on leaves and stems.
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Asian Citrus Psyllid Distribution and Management: Page

How do I look for it?

How do I find psyllids? Check your citrus trees monthly. Whenever you see tiny new leaves forming (leaf flush), look closely for signs of the psyllid. Remember the adults fly and so they may be hard to observe and the eggs are so tiny they are hard to see without a hand lens.
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Asian Citrus Psyllid Distribution and Management: Page

Biological control

Tamarixia wasp parasitoid. Photo: M. Lewis The Asian citrus psyllid is attacked by many natural enemies, including lady beetles, lacewing larvae, syrphid larvae, minute pirate bugs, parasitic wasps, spiders, and birds.
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Asian Citrus Psyllid Distribution and Management: Page

Insecticidal control

Soil application of systemic insecticide by licensed applicator for sustained control of ACP.
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Asian Citrus Psyllid Distribution and Management: Page

Eradication strategy

Principles for treating commercial citrus orchards following the first appearance of ACP or where aggressive action is being taken in HLB quarantine areas: Apply two ACP effective insecticides with different modes of action as soon as possible after detection of ACP, with at least one from the broad...
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Asian Citrus Psyllid Distribution and Management: Page

Area-wide treatment programs

Once the psyllid is found in multiple sites, in multiple stages, and it is clear that it is established in a region, the strategy becomes one of keeping ACP populations as low as possible (
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Asian Citrus Psyllid Distribution and Management: Page

ACP effective insecticides

See individual pesticide labels and the UC IPM guidelines for citrus for rate recommendations. Many insecticides are effective in killing psyllids, especially if they make direct contact. Synthetic Insecticides known to be effective for ACP management.
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Asian Citrus Psyllid Distribution and Management: Page

Monitoring

The goal: To drive psyllids below an average of 0.5 nymphs/flush. If the center row has zero nymphs, then a border only treatment between coordinated treatments could be applied to reduce psyllids below this threshold. The psyllid prefers borders and so the focus is on the outside edges of orchards.
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Asian Citrus Psyllid Distribution and Management: Page

What should I do if I find it?

If you find the Asian citrus psyllid, you should check the Distribution of ACP in California tab to determine if the psyllid and its parasites (Tamarixia) have been found in your area.
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