Hello, this is Dr. Linda. I hope I can help with your question today.
Any animal presented with a balanced, & complete diet, plenty of good clean & adequate pasture & a good deworming program, will do very well. But nothing will prevent a potential infection from getting into your herd without some type of vaccination protocol. There are no oral or supplemental substitutes to this.
All breeding beef should be vaccinated for the major respiratory & clostridial diseases. Keeping your animals on a superior diet, & rotating your fields to prevent over grazing & parasite buildup will keep them stress free & much more able to fight disease, but will not prevent someone at sometime getting sick. And you will have to be extremely careful when you introduce a new animal into your herd, especially if it is coming from a sale barn.
I guess what I am trying to say is there is no substitute for a good vaccination program, & vaccinations require injections.
I am not sure if this is the information you were looking for. Did you have a particular product or program in mind? Even grass fed/organic beef allows for vaccinations.
So, if I can help in any other way, please let me know.