It is time to take alternate metheods. Regardless, DO see the vet, he could have a yeast in fection from high doses of antibiotics, a bacterial/fungal infection, or various parasitic/protazoan complications.
Now that I've said that...gather up the following supplies:
Calcium powder
fruit babyfood
chicken babyfood
ben-bac (or bird hand feeding formula)
para-zap
pedialite (electrlites)
(normally I would say syringe feed parazap tea prior to the above mixture, but this Leo seems too far gone and in immediate need of food)
So, using a pinch of the powders, mix it into 2 table spoons of each of the baby foods and add a table spoon of pedialite. These are only approximate measurements.
Fill an oral syringe with the mixture (add pedialite until easily sucked up the syringe - but you don't want it watery).
If the Leo refuses to lick the drops of mixture from the syringe, touch the side of his mouth with it until he bites at it. Move the syrnge so that it is at the back of his throat. Slowy, a drop at a time, dispense the mixture. 1cc a feeding (3xs a day or more) until he can comfortably hold 3cc a feeding.
I've used this method to keep animals alive before. Make sure to follow up with meds he needs or you will be feeding him the rest of his life, which may not be very long.
Good luck!
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