312 



NORTH AMERICAN FAUNA 68 



weight) injected intraperitoneally caused death in a sea otter in 

 less than 30 minutes. One-half the dog dose gave good anesthesia 

 but thermoregulation was upset. No further experiments with 

 Nembutal were conducted. 



Promazine hydrochloride "Sparine" (Wyeth) 



The use of this tranquilizer was suggested by K. L. Binkley, 

 D.V.M. It was found to be a useful agent in speeding the adjust- 

 ment of nervous animals to captive conditions. The dosage of 

 1 mg. of Sparine per kg. (2 mg. per lb.) of body weight was satis- 

 factory. The intramuscular injection took effect within 5 minutes. 

 The animals so treated remained in a relaxed state for about 24 

 hours. This degree of sedation is, however, usually unnecessary 

 and under certain conditions harmful, since food intake and pelage 

 care were substantially reduced during the tranquilized period. 

 We found that about half this dose or less, i.e., about 0.5 to 1 mg. 

 Sparine per lb. of body weight, induced adequate tranquility and 

 that the otters gave nearly normal attention to their bodily needs. 

 When the effects of the drug wore off, the treated animals in all 

 cases remained tame and well adjusted. 



Sparine was particularly useful when mothers with small pups 

 were captured. On one occasion a mother with a newborn pup was 

 placed in the enclosure without receiving an injection. The mother 

 grasped the pup in her mouth and swam frantically about the 

 pool seeking escape (fig. 121), rather than swimming in the normal 

 manner on her back with her pup on her chest. She surely would 

 have drowned the pup if we had not recaptured her, taken the pup 

 from her, and given her the minimum injection. Within 5 minutes 

 we returned the pup and the mother cared for it in the normal 

 way from then on (fig. 122). 



Usually when a sea otter pup was taken from its mother it 

 cried almost incessantly, day and night, and accepted little food 

 voluntarily. We found that after a minimum injection of Sparine 

 such orphans became calm and after the effects of the drug had 

 disappeared the pup appeared to have become "imprinted" on 

 the human foster parent. Treated pups readily accepted food and 

 only cried when desiring attention. Unfortunately, time and facili- 

 ties were not available to maintain helpless captives indefinitely. 



No harmful side effects from minimum injections of Sparine 

 were detected in otters kept in a satisfactory enclosure with a pool. 

 Because it was important that sea otters give frequent attention 

 to their pelage and maintain their daily intake of food, it was 

 desirable that use of tranquilizers be kept to a minimum. The 



