306 GUY A, VOISIN AND RADSLAV KINSKY 



the same figure shows that, in addition to mortaHty from runting 

 being much less important in the protected animals, it is also 

 delayed, reaching its maximum around day i8 and decreasing 

 progressively to become almost nil by day 35. It should be noted 

 also that between day 21 and day 28, the mortahty rate is signi- 



Days after birth 

 2L 28 25_ 



Days after birth 



Fig. 6. Histograms showing the ratio of percen- 

 tage of deaths per day of age in the two series : 

 unprotected (upper histogram) and protected 

 (lower histogram), between birth and day 35. 



ficantly higher in the protected series than in the unprotected 

 series. 



However, these differences of chronology between the two 

 series do not affect the clinico-pathological picture of runting, 

 which was exactly the same in the two series in the animals in 

 which it occurred. The picture conformed in every respect to the 

 classical one (Billingham and Brent, 1959). 



