...it's hard to say exactly what precautions you should use without knowing the active ingredients in your herbicide. I tried to search for evidence based data and only found information on the benefits of using weed killer around barns and coops... and one article on the chance that too much herbicide could disrupt the natural flora in an animals gut (being that it can be similar in structure to plants..in which case probiotics could remedy
.. to give me a baseline I initiated a chat with a live person from round-up. The agent said that it depends on the product so I used" ready to use weed and grass killer" as my example (again, if this is NOT what you used you will need to check the exact type to get true answer. I've copied and pasted the conversation below:
Yecenia: Hello, how may I help you today?
cherie: what is the procedure for safe use around chickens? what time frame should I give before allowing chickens to free-range where they may come in contact with areas?
Yecenia: Using which product?
cherie: the weed killer
Yecenia: Which weed killer? we have many
cherie: weed and grass killer ready to use
Yecenia: One moment
Yecenia: Chickens can be allowed back into area where weeds have been treated once the product has dried.
Yecenia: Drying time will vary based on wind, humidity and sunlight, if concerned about when product is dry, wait 24hrs before allowing grazing animal to reenter area.
Yecenia:
cherie: is that a good general rule for all of your products or are there some I should outright avoid?
Yecenia: This is for Roundup Weed and grass killer.
cherie: ok, thank-you. is your chat line open 24/7 for further questions?
Yecenia: Monday-Friday: 8am-10pm EST
Yecenia: Saturday: 8am-8pm EST
Yecenia: Sunday: 8am-8pm EST
Yecenia:
cherie: thank-you