PREVENTION OF DISEASE. 45 



we may expect, and may be accepted as being authoritative. The 

 question arose out of the killing of some sheep on a railroad by a 

 passing train, and it was denied that the complaint was properly 

 made, the animals being lambs, and not sheep. The judge decided 

 that lambs ceased to be lambs, and became sheep as soon as they 

 had acquired their first pair of permanent teeth. This change of 

 teeth generally occurs when the lamb is a year old. At this period 

 the middle pair of the first teeth drop out, and a pair of the per- 

 manent incisors appear. At one year and nine months, two more 

 of the first teeth are dropped and two more permanent incisors, 

 one on each side of the former pair, appear. Nine months later, 

 two more permanent incisors appear in a similar manner, and nine 

 months later still, another pair are produced, so that at three years 

 and a quarter the sheep has eight permanent incisors or nippers, 

 and is then called a full-mouthed or perfect sheep. These periods 

 of dentition are irregular, and in some of the early maturing 

 breeds, the first pair of permanent teeth will appear before the 

 end of the first year, and at 16 months, four permanent incisors 

 may be found. The earlier maturity of the high bred and high 

 fed races of sheep, such as the Leicester, Colswold and Shrop- 

 shire, sometimes amounts to a gain over the common breeds of 

 nearly a year in time, and full-mouthed sheep of no more than two 

 years and a half old are not uncommonly met with. 



The diseases to which lambs are subject are but few, and those 

 are mainly the result of carelessness in their management. The 

 lamb, which appears so delicate and tender an animal, is really 

 hardy, and resists much ill treatment, else with so little consider- 

 ation as they usually receive, the race would soon become almost 

 extinct. Damp and cold are especially to be guarded against in 

 the spring, and filthy yards at all seasons. With clean pens and 

 dry, clean bedding, they will resist the severe dry colds of a north- 

 ern January, and thrive and grow while snow storms rage, if 

 only well sheltered. Sunshine has a remarkable effect upon 

 lambs, and the warmth of the sun will often revive and strengthen 

 a weak lamb that appears past relief. Extremes of damp and im- 

 pure air in close pens, and bad drinking water, will produce diar- 

 rhea and paralysis, and these are the chiefly fatal disorders to 

 which they are subject. Constipation is produced by want of 

 proper laxative food, and permitting them to feed on dry, withered 

 herbage that has lost its nutritive qualities beneath the storms of a 

 winter. If the directions as to their treatment heretofore given, 

 are followed, there will rarely be any need of remedial measures, 

 and prevention will be found better than any amount of cure. It 



