I have a calf that does not act just right to me seems kind of droupy may be breathing a little hard ,not bad but some,he is around 4 months old still on the cow. our weather in the last 3 months has been up and down from ice and below 0 to low 80,s has done this several times thought that may have something to do with it ????Ihave some Terra-Vet 200 (oxytetracycline) also have some Bactracillin G. would anyone of these help if he is coming down with something?