TYPES AND MARKET CLASSES OF LIVE STOCK 209 



lings from mature sheep. The break-joint or lamb- joint is a 

 temporary cartilage which forms in the head of the shank (shin 

 bone) immediately above the ankle. In dressing lambs, year- 

 ling wethers, and some yearling ewes, the foot can be broken 

 off at this cartilage, giving the end of the shank a saw-tooth 

 shape. In lambs the broken surface is smooth and moist, and 

 in yearlings it is more porous and dry. The shanks of mature 

 sheep will not "break," because the cartilage is knit or ossified, 

 and the foot is taken off at the ankle instead, making a "round- 

 joint." Shanks of female or ewe sheep outside the lamb class 

 are, as a rule, too mature to break. Consequently, 80 to 90 per 

 cent, of "yearling lamb" carcasses are wethers, the remainder 

 being ewes and a small proportion of bucks and stags. Yearlings 



Fig. 58. Round-Joint and Break-Joints. 



In dressing mature sheep, the feet are taken off at the ankle, leaving a 

 round-joint on the end of the shank bone. Immediately above the ankle 

 in immature stock is a temporary joint, called the break-joint, at which the 

 feet are removed. Thus the head of the shank bone as well as the foot is 

 removed, leaving the saw-toothed break- joint on the end of the shank bone. 

 As the animal matures, the break-joint ossifies or knits. Pincers are some- 

 times used to crush off those which are partly ossified. This leaves an im- 

 perfect break-joint. The shank bones of mature sheep will not break. At 

 the left above is a round-joint, at the right a true break-joint, and in the 

 center a crushed break- joint from a nearly mature sheep. 



substitute for genuine lamb, and we see that they may easily 

 do this because they possess the break- joint. 



Goat carcasses. Dressed goats are occasionally sold in 

 connection with mutton and lambs, and are frequently sub- 

 stituted for them, especially in the retail markets. They are 

 similar to the lowest grades of western sheep in form, quality, 



