The effects of complete extirpation of the hypophysis in the dog (Preliminary report)

Abstract

A series of 66 dogs were operated through the oral route and the hypophysis removed by cautery. Five of these animals (Nos. 4, 30, 34, 35, 40) showed no clinical symptoms, and when killed for examination 96, 95, 95, 146 days after operation, no trace of hypophysis was found microscopically. One animal (No. 38) died 15 days after operation. This dog showed the symptoms of so-called cachexia hypophyseopriva. Autopsy showed absence of hypophysis, a blackening of the region about the infundibulum and a severe pneumonia. The pneumonia was probably an aspiration type and was diagnosed as such two days after the operation. Dog No. 52 remained alive for 259 days after hypophysectomy. This dog was adult at the time of operation, weighing 18 K. After hypophysectomy the dog gained 7 K., became sluggish, and somewhat somnolent. There was no demonstrable decrease in the size of the testes (weighed 31 g. at the time of death) and there was no microscopic trace of the hypophysis at autopsy.

Two dogs (Nos. 14 and 39) are still alive, two years and nine months and one year and nine months after hypophysectomy respectively. Dog 39 was adult at time of operation, weighing 5.8 K. After the operation this dog gained six kilos in weight, became extremely sluggish and somnolent (sleeps practically all the time), shows altered disposition (grouchy) and is devoid of sex interest (tested with bitch in heat). There is no gross decrease in the size of the testes as determined by external measurement. This animal showed polyuria and polydypsia for some time following the operation. Dog 15, a female pup, weighed 3 K. at time of operation. After the operation the pup gained four kilos, while the control gained six kilos.