12 DEPARTMENT OF GAME AND FISHERIES No. 9 



soon ferments, the milk becoming curdled. This is especially the case if it is 

 left in the sun. The condition is caused by bacteria in the bread. Flour kept 

 in large bakeries has been known to contain the organism and when made into 

 bread, the bread becomes ropy. The bacterium is claimed to be harmless to 

 humans, but severe outbreaks of a convulsive nature have occurred among 

 foxes and mink soon after consuming ropy bread and biscuits known to contain 

 the organism. 



Moulds in bread or meat produce poisonous substances and when the bread 

 or meat is eaten, symptoms of intoxication follow. 



Mink have the habit of storing food in their nest boxes, which in time 

 becomes spoiled and consequently leads to food poisoning. In cases of outbreaks 

 among mink the history usually indicates spoiled food as the cause and the 

 symptom.s are fairly constant. The following extracts describing observations 

 in connection with mink that have died of food poisoning bring out the history 

 of such cases very clearly. "Mink appeared very active and was looking well 

 but seemed to take an attack of indigestion, by the way it acted. It was fed 

 frozen herrings that were noticed to be very soft and have a slight foul odour, 

 but they were washed before being fed to make them fresh. The herrings were 

 obtained in a frozen state from a commercial house. At the ranch they were 

 kept in a refrigerator which would only keep them cool, in a little time they 

 would become soft." Another extract states: "Two apparently died suddenly 

 as they were found dead in the nest box. The other one showed sickness for 

 two days. Worms or food poisoning suspected as being the cause of death. 

 Old bear meat had been added to the diet for the two days just previous to the 

 death of the mink. Other mink on ranch were normal." The following case 

 is quite typical of food poisoning: "Mink apparently all right as far as could 

 tell. It was always ready for its feed and ate its evening meal. Was found 

 dead in the nest box the next morning. Some time ago I had two other mink 

 die suddenly. They were also found dead in the nest box. One showed a variable 

 appetite, at times would eat a little food and appear all right." 



The history of another form of food poisoning which is sometimes met 

 with in mink is as follows: "Two females for about ten days were doing a lot 

 of running about their pens. In a few days they took fits, would run around the 

 pen, roll over a few times and then curl up as if in great pain. During this spasm, 

 their feet and body would be kept in motion. In a few moments the body would 

 relax, then maybe they would get up and walk around the pen for a few minutes 

 after which they would curl up and go to sleep." 



The symptoms shown in mink affected with food poisoning vary according 

 to the conditions under which the infection takes place. Mink may die without 

 showing any symptoms whatsoever; in these cases they are usually found dead 

 in their pens or nest boxes or they may be seen playing about their pens only 

 to be found dead in a few hours afterwards. Such is the case when very large 

 amounts of toxic materials have been taken into the body. In these cases very 

 few lesions are found on post-mortem examination. Animals may sicken suddenly, 

 often exhibiting manifestations of abdominal pain. These may be so sharp and 

 severe as to lead to maniacal attacks. The symptoms may be accompanied 

 by great prostration; the animal may lie on the floor, stupefied and motionless, 

 or may go into convulsions. Dizziness, muscular contractions, frothing at the 

 mouth are also symptomatic. In prolonged or chronic cases the appetite becomes 

 variable; some meals are taken in a normal manner, then again there may be 

 an entire absence of appetite. Thirst may be either diminished or increased, 

 some animals taking only fresh cool water, others again taking contaminated 

 stale water. Vomiting is sometimes manifested and often occurs after the 



