an in vivo experiment was conducted to determine the effect of dietary betaine supplementation (betafin®) as a replacement for methionine on broiler performance and carcass characteristics. in a completely randomized design (crd) with five treatments of betaine levels (at 0, 25, 50, 75, and 100% in replacement for methionine) and five replicates of 10 birds/replicate, two hundred fifty-day-...

This paper tries to trace our research history briefly from Barlow and Proschan to attain general replacement models. We begin with a random age replacement policy that is planned at a random time Y and call it as random replacement. When the distribution of Y becomes a degenerate distribution placing unit mass at T, age replacement is formulated. We obtain the general formulas for optimum repl...