Withdrawl period with Topical use of antibiotics?

[CottageFarm]

I'm helping with a herd that belongs to friends who are away on vacation (out of the country)
There is a cow scheduled for the processor in 10 days that managed to put a big gash in her front leg 2 days ago.
I'm going over to look at her tomorrow morning (haven't seen her yet). The caretaker has been spraying the wound with iodine, but that's all he's been able to do. Fly season is just starting here. He hasn't been able to wrap it because he's not been comfortable trying to get her in a chute up to this point. I can't give any injected antibiotics and keep the slaughter appointment. She's not lame or even limping. She's eating and drinking normal. Don't know about her temp. My main concern is infection developing in the wound prior to her slaughter date.

My question is/are...Would topical use of either Pen G or LA200 combat/prevent infection, and would the topical application eliminate any need for a withdrawal period since it's not in the bloodstream?

 

[Alan]

The only real, correct answer you'll get is to find out what has been used on the cow, call the manufactors and get the correct answer.

 

[CottageFarm]

Nothing has been used yet Alan, other than iodine.

 

[crimsoncrazy]

LA 200 has a 28 day slaughter withdraw. Pen G is 10 days.

 

[Lucky_P]

As neither of these products are intended for topical use - and are probably virtually ineffective when used as such - there will be no established meat/milk withdrawal times; in fact, using them topically will be considered 'extra-label drug use'.
I suspect that if you're able to speak with someone at the drug manufacturer, they'd tell you not to bother - or, they'd merely be bound, by law, to tell you what the established withdrawal time are for the respective drug, when given at the approved dosage rate and route of administration.

 

[CottageFarm]

Thanks Lucky. We decided to just stick with iodine for now, for those precise reasons.
Hopefully it will continue to heal without any issues prior to slaughter.