brake n3 Also cow brake, milk(ing) ~  Also sp break [By ext from brake “A frame for confining refractory animals while being shod or undergoing operations” (1872 (1876) Knight Amer. Mech. Dict. 1.357); cf OED2 brake n.6 1, 2.a; EDD brake sb.3] Sth

A cage or small pen in which a cow is confined for milking; see quots.

[1887 Johnson From Pacific 35 CA, The horse you can get shod any where on the road, but the cow few can shoe. In shoeing her she will have to be confined in a brake that will hold her secure.] 1925 Winston-Salem Jrl. (NC) 22 Dec 13/2, Robertson, eyeing the fruit jar like a calf eyeing its mother being backed into a milking brake, remarked: “Detective Moses, is my nose trickin’ me, or does I smell gin?” 1949 Kurath Word Geog. 55/1, In Delamarvia and on Albemarle Sound (cow) pound still predominates, and in a belt directly west of the pound area on Albemarle Sound one hears cow brake (from the James to the Neuse). Ibid Fig 61, Brake or cow brake. 1958 Cheney Adam 149 sGA, Hastily she opened the barnlot gate. At a distance, amid the bog of mud and manure about the cow brake by the back fence, she saw the empty milk bucket on the milking block. 1966–70 DARE (Qu. M11, What do you put the cow’s head through when she stands in the barn?) Infs AL2, FL20, 37, GA7, MS87, NC15, Brake; SC7, Brake, a close stall, a narrow stall. 1966 DARE FW Addit SC, Break—a pole in a stall that a cow is required to straddle to keep her from kicking; also the whole stall with such a pole. 1971 Wood Vocab. Change 47/1 AL, GA, TN, Cow brake, cow pound, cuppin, and farm lot are chosen more often east of the Mississippi than west of it. [5 instances of cow brake from approx 1000 infs] 1989 Pederson LAGS Tech. Index 56 Gulf Region, (Milk gap) 8 [of 914] infs, Break; 1 inf, Milk break. 2012 Cumbie All Roads 88 csAL (as of 1930s), Papa showed Pudge and Cephas how to train a young cow for milking. As soon as she was ready to be bred, Papa began feeding her in a cow break, which consisted of a cage-like structure six or seven feet long and two to three feet wide. Once the cow was enticed into the cow break by a trough full of crushed feed, Papa told Pudge to close the cage on both sides to hold her in place. . . An important part of the cage was a small board placed across the cage to hold the left hind leg back and the right hind leg forward.