Abstract
Male Japanese quail, force-fed for 4 wk, showed a marked increase in weight resulting mainly from the deposition of fat. Obesity, induced by forced feeding, was accompanied by increases in colonic temperature (about 0.3.degree. C), peripheral leg temperature (about 3.degree. C) and by a decrease of the mid-scapular skin temperature (about 0.6.degree. C). Testicular weight decreased by 30% during the period of overfeeding and the spermatozoa concentration in the testis and ducti deferentes decreased by 50%. There was also a small increase in the cholesterol concentration of the testis; testicular cholesterol concentration was negatively correlated with testicular weight. A marked decrease in the concentration of the plasma testosterone was accompanied by regression of the tail and by a reduction in the volume of cloacal foam secreted.