U DEPARTMENT OF GAME AND FISHERIES No. 9 



with lymph vessels. The toxic substances having reached the digestive tract 

 are then absorbed because they cannot be destroyed by the intestinal epithelial 

 cells, or by the digestive enzymes, because they are present in such very great 

 quantities. The absorption of the bacterial endotoxins and of the products of 

 motion cleavage give rise to injuries affecting the parenchymatous cells. The 

 bacteria which enter the general circulation without being dissolved immediately, 

 may produce local inflammation in distant organs. Hence we may find small 

 petechial hemorrhages in the spleen, kidneys and heart which are very common 

 lesions in these organs when the animal has died from food poisoning. When 

 pathological lesions are present in these organs they are caused by the patho'renic 

 bacteria or their toxins being picked up by the blood stream and carried to 

 these organs where they exert an injurious effect of varying degrees upon the 

 organ tissue. The absence of lesions in these organs indicates that the causative 

 bacteria or their toxins have not been able to reach the more distant organs 

 through the circulation because the action on the animal organism has been 

 so severe that death ensued before they had reached such organs as the spleen, 

 kidneys, etc. 



In some cases the spleen may show small petechial hemorrhages or it may 

 be enlarged to four times its normal size, greatly thickened and of a tarry black 

 colour. The kidneys may show inflammation and petechial hemorrhages. The 

 liver may be enlarged, swollen, soft and friable, its capsule being broken when 

 handled. Its colour may range from a dark chocolate brown to an ash gray 

 colour or a mottled appearance. The lobules may show quite prominently. 

 It may also show hemorrhagic areas. Small hemorrhagic areas may be found 

 on the heart muscle especially near its base or along the course of the coronary 

 artery. A straw-coloured fluid is cften present in the pericardial sac. 



Pathology. — Marked hemorrhages and profuse extra\'asations of red blood 

 cells into the surrounding tissues is the most prominent feature seen on micro- 

 scopic examination of sections of tissues taken from mink that died of acute 

 food poisoning. There is a marked engorgement of the blood vessels; their 

 walls appear thin and stretched and in many places they have been destroyed, 

 leaving openings through which a profuse pouring of red blood cells into the 

 surrounding tissues has taken place. 



In the stomach and intestine, in most places, the points of the crypts are 

 destroyed and in many areas destruction of the entire crypt has taken place. 

 The spaces above are occluded with debris, composed of broken down tissue and 

 red blood cells that have been poured out in huge quantities from between the 

 crypts. 



The kidney tissue shows cloudy swelling. The cells of the convoluted and 

 collecting tubules are broken from their base and the cellular cytoplasm is 

 seen in various stages of disintegration, the lumen of the tubule becoming 

 obliterated. Extravasation of red blood cells is found throughout the kidney 

 tissue. Marked hemorrhages in many of the glomeruli are noticed. 



In affected parts of the liver tissue the cytoplasm of the cords in the lobules 

 have lost their definite structure and are for the most part destroyed. 

 Hemorrhages from the blood vessels are present. The central vein and sinusoides 

 are engorged with blood and in many instances to such an extent as to cause 

 the destruction of their characteristic structure. 



In a spleen that is enlarged, thickened and black in colour, microscopic 

 examination reveals the blood vessels to be extremely engorged and numerous 

 hemorrhages occurring. The cellular differentiation is obliterated. The cytoplasm 

 stains a very deep red colour. 



