248 Cattle Problems. 



milk glands with'milk; the over-distention in either organ 

 not being so extreme as that which culminates in abort- 

 ment ; but still the over-strain is sufficient in extent to 

 cause partial relaxation of the udder-supply arteries. And 

 this limited degree of weakening by over-distention and 

 partial relaxation may be sufficient so prevent the neces- 

 sary supply of blood and blood heat to the region of the 

 ovaries, to bring on coupling fever. 



During a season of rest, contractility in the weakened 

 arteries is partially regained, a sufficiency of blood again 

 ilows towards the ovaries to bring on coupling heat, in 

 some cases, and breeding may be resumed. Thus the in- 

 termitted breeding of farrow cows is accounted for by the 

 occurrence of partial relaxation in the udder-supply ar- 

 teries. 



