A turnpike rd. was a toll road,so it's probably been renamed.Look on the 1851 census for ajoining roads or if you look on the original census page 1 shows the route taken by the enumerator.
Turnpikes were usually main routes from one town to another as these carried the most traffic.
It's looking like the A425 Shuckburgh Rd. as the other roads mentioned on the 1851 census are Butt Hill St. & Tomlow farm (Tomlow Rd.).Butt Hill ran into Tomlow farm with the Shuckburgh rd. running across it.
jim
Edit:
found this article:
January Lotcer Shuchburyh. — Found at Caldecott Spinney, ran towards the hill. Init turned to the left under the A'illage, and pointed for Grandborough ; after going two fields the fox was headed by some people coursing,and went for Broadwell. near which village we gave him up. Got away from the hill at Shuckburgh as if for Badby,turned to the left immediately, and crossed the turnpike road, and went straight for Flecknoe.
According to this it still looks like the A 425.
