A protein produced by cells after they have been exposed to a virus. Interferon prevents the virus from reproducing within the infected cells and can also induce resistance to the virus in other cells.
Calves can be ready for weaning by 3 to 4 weeks of age; however, in Penn State studies calves weaned at 3 weeks required extra attention. The increased time and labor required to get these calves eating starter suggest that waiting until 4 weeks of age would be prudent.
It supported the early-weaning concept. We also have collected data from 3,300 calves fed at conventional and moderately accelerated milk replacer programs and weaned at either 4 or 6 weeks. More than 94 percent of the calves in a conventional system were weaned on time with a four-week weaning program (Table 1).More than 99 percent of the calves in a moderately accelerated milk replacer program were weaned successfully with a four-week weaning program.ore than 94 percent of the calves in a conventional system were weaned on time with a four-week weaning program (Table 1). More than 99 percent of the calves in a moderately accelerated milk replacer program were weaned successfully with a four-week weaning program.