Further studies of the thyroid gland. V. The thyroid gland as a growth‐promoting and form‐determining factor in the development of the animal body

The Effects of Nutritional and Endocrine Factors on an Inherited Retinal Degeneration in the Mouse

“…Hoskins (1927) has reported that regular treatment of normal newborn rats with acetyl thyroxin accelerates develop¬ ment of epiphyses, eyes, and skull without corresponding increase in body size. Con¬ versely, both dimensional growth and tissue maturation in many mammalian species (sheep, dogs, cats, rabbits, rats) have been retarded by thyroidectomy soon after birth (e. g., Dye and Maughan, 1929;Todd, Wharton, and Todd, 1938). In newborn rats, this treatment resulted in cretinism and delayed opening of the eyes (Salmon, 1938(Salmon, , 1941Scow and Simpson, 1945) ; hypothyroidism induced in similar animals by feeding the mothers with propylthiouracil had comparable effects, including develop¬ mental failure of the eyes (Fazekas, Graves, and Alman, 1951).…”

Inheritance of bovine dwarfism and the detection of heterozygotes

“…The four bulls proven to be heterozygous, the suspected heterozygotes, and the nine proven by progeny tests to be free from the dwarf gene are indicated, tests until the inheritance and relationships of all the genes involved are clearly understood. The experimental anatomists who have devoted attention to skull shape are well aware of the influence of the thyroid gland in determining head and body form (Liddell, 1925;Dye and Maughan, 1929;Dye and Kinder, 1934;and Todd and Wharton, 1934). The experiments of Spielman et ale (1945) show that the response of the bovine to thyroidectomy is in line with that of other animals.…”

Are the small human-like fossils found on Flores human endemic cretins?

“…(c) Postcranial features Experimental thyroidectomy reduces growth in limb bone lengths (endochondral) more than widths (subperiosteal), thus simulating increased robusticity that was increased by a factor of 1.3 in experimental dog cretins (Dye & Maugham 1929). Both DC and LB1 show this (table 2) and have long bones that are smooth with poorly marked muscle scars inconsistent with true robusticity.…”