Lucky_P":2a7vuqli said:
Standby/go-to is oxytetracycline, in a long-acting formulation. If you dose it properly, OTC will be present in the tears, continually, at the same concentration as it reaches in serum/tissue fluids, for the 3-4 days that the antibiotic stays at treatment levels.
However, we're seeing some strains of pinkeye bacteria that are resistant to OTC... Draxxin would likely be my 'go-to' for those.
Anything you spray or squirt in the eye will be washed out within 10-15 minutes, maximum.
I'm not convinced that the old subconjunctival injections (yes, I did them when I was in practice) do anything, once the needle be nice seals over and the injected antibiotics/steroids stop leaking out.
Patching or sewing lids together helps...
Yesterday, Shannon Ferrell our UK Agent was here and performed a total herd assessment. Lucky, you may know her as part of Double Diamond Farms, Cynthiana. Her dad is Mr. Wade. They were at the Bulls of The Bluegrass. We discussed pinkeye. The topic got around to WHY DOES THE DISEASE BLOOM THEN DISAPPEAR? There was a period from middle March until end of April when it was epidemic. Then it disappeared. What is remarkable is that the bloom did not coincide with the fly season. Personally, I don't believe flies are as great a factor as many producers think it is. In undergraduate and graduate studies I took a lot of entomology, including medical entomology. The history on the biology of Dipterans is interesting. In early Europe flies were considered the primary vector of all disease because flies and maggots were associated with wounds and ailments. In the 1900s, studies began to dispell that concept by finding that flies are vectors but not as effective as once believed.
In addition, I discussed pinkeye with Stanfield, DVM (Auburn). He said Moraxella is generally already in the eye from swabs he does. If so, then a vector is not needed just the proper conditions for the disease to manifest itself.
Personally, I think a small abrasion plays a greater role than flies in causing pinkeye. I have not researched available studies. Are you familiar with any?