15 



Feeding of Small Amounts at Stated Intervals Mixed with Hay. 



The object of this series of feedings was to determine whether small 

 amounts of air-dried arrow-grass (the total of which if fed at one time 

 would cause sickness or death) would be harmful when fed a little at 

 a time at various intervals. None of the animals were affected except 

 No. 62, which showed symptoms of poisoning after the fourth 1-oz. dose. 



The above feeding tests show that there is little or no cumulative 

 effect of small doses fed at short intervals or over a long period of 

 time. Previous to these tests a sheep had been fed 4 ozs. of air-dried 

 arrow-grass which readily killed the animal. However, when 4 ozs. of 

 similar material was fed in 1-oz. doses to a sheep at hourly intervals 

 only sickness was produced. On August 8 at 9 : 50 a. m. a sheep was 

 given ^ oz. and thereafter -|-oz. feedings were made at approximately 

 hourly intervals until 6 : 10 p. m. when 1 oz. was fed. In all between 

 9 : 50 a. m. and 6 : 10 p. in. 5 ozs. had been fed without producing any 

 visible symptoms of poisoning. 



On August 21 at 10 : 30 a. m. a prolonged feeding test was com- 

 menced and continued until 5 : 10 p. m., August 23, during which time 

 45 separate feedings w;ere made of five 1-oz. feedings and forty ^-oz. 

 feedings or a total of 25 ozs. with negative results. 



From these feedings it appears that there is no cumulative action of 

 the poisonous principle of arrow-grass when eaten in small amounts- 

 of less than 1 oz. at short intervals. It may therefore be safely con- 

 cluded that an animal may eat many small amounts either in hay or 

 on pasture with little danger. Thus, if small quantities of the dried 

 material are uniformly scattered through the hay, there is not much to 

 worry over, so far as the health of the animals is concerned. On the 

 other hand, if there is any considerable quantity in the hay, fatal 

 results may be expected especially if fine, broken material collects in 

 the bottom of the feed racks. Dry arrow-grass is very brittle, easily 

 broken, and may very readily sift to the bottom along with seeds, chaff, 

 and other material. If this takes place, then there is a possibility of 

 fatal poisoning, even though there is only a small amount of the plant 

 in the hay. 



DETAILED DESCRIPTION OF TYPICAL CASES OF ANIMAL POISONING 

 Case No. 1 No. 39. 



f 



A sheep weighing 97 pounds was fed 4^ pounds of green arrow-grass 

 leaves at 3 : 10 p. m. October 8, 1918. The animal appeared sick at 

 3 : 25 p. m. within fifteen minutes after feeding. Muscular spasms com- 

 menced at 3:30 p. m. ; hindlegs pulled up under body; frequent 

 champing of jaws, breathing hard and audible. At 3 : 40 the sheep was 

 breathing through the mouth which was held wide open with the 

 tongue hanging out ; temperature, 102 ; respiration, 30. At 3 : 50 p. m. 

 spasms continued ; 3 : 55 p. m., respiration, 21 ; at 3 : 58 p. m., severe 

 spasms commenced and breathing practically stopped ; at 4 : 03 p. m., 

 respiration 12, with long intervals between breaths. Expulsion of 

 breath forcible and plainly audible ; at 4 : 12 p. m. respiration had 

 fallen to 8. Death occurred at 4 : 13 p. m. 



Autopsy showed the jejunum severely congested ; spleen dark and 

 mushy; kidneys congested ; lungs slightly congested ; other organs all 

 appeared normal. 



