bottle feeding calves

I have been tasked with caring for 4 sale barn Holstein babies. I think they're 1-3 weeks old none are tiny and young. 2 are vigorous and fine.. all 4 had a shot of antibiotic from the sale barns vet ( I do not know what it was ..) maybe exceed..? I have banamine on hand 2 act like they...

Got calf at 3 days old and bottle feed. Now he's about 1 mo. old. He ate fine at first but has progressively gotten slower. He wants to suck but is having trouble doing so. It takes him an hour to eat a bottle. He doesn't seem interested in grain or hay. His tongue hangs out of the right side of...