The weight curves of castrated kids.

Abstract

Twin kids, born February 5, 1923, were used for the experiments. One, without horns, was used as the control; the other with horns was castrated at the age of 74 days. Later another kid with horns born April 1, 1923, was castrated at the age of 83 days and was added to the experiment. The age at which the operation was performed, it is believed, caught the young goats at about half way to the age of puberty. Daily records (except Sundays) were kept of the weights since the operations. Weekly averages were obtained, and another average based upon four of the weekly averages was taken as the average for an approximate month.

For a period of eight months after the operation in the case of the first castrate, and of nine months after the operation in the case of the second castrate, there was apparently just as favorable growth in the castrates as in the control. From this point onward for nearly a year, there has been no material gain in the weight of the castrates although there have been minor fluctuations. The growth of the control, as evidenced by his increased weight, continued for seven months longer, when he weighed about 100 percent more than the castrates. Reckoning from the time of the operation, the growing period for the control lasted fifteen months while that for the castrates lasted only eight and nine months respectively. The removal of the testicles had abbreviated the growing period of the castrates by about seven months as compared with the control. Fig. 1.

During the eighth month it was discovered that the first castrate and the control had been deprived of salt for probably two or three weeks. (The salt brick had broken and the pieces were covered by the bedding.) During this period the weight of both goats diminished but gradually returned to the original level after the salt was renewed. The second castrate received salt continuously, and there was no depression of his weight at this time.