The Etiological Factors Involved in the Malformation of Bones in Young Chickens

Mineral Content of Tibiae from Chicks with Slipped Tendon

“…The results obtained do not reveal any significant difference between the size and mineral content of tibiae from slipped-tendon chicks and those of normal chicks. These results are in accord with the reports of Hall and King (1931) and Payne, Hughes and Leinhardt (1932) who concluded that slipped tendons in growing chicks are not primarily due to faulty mineral metabolism.…”

“…From these data it does not appear that slipped tendon in growing chicks is primarily due to faulty mineral metabolism. This conclusion is in accord with Hall and King (1931) composition of the structure of the bone" and of Payne, Hughes and Leinhardt (1932) who conclude that "the condition appears to be of an anatomical rather than histological nature. "…”

“…It is the opinion of Bethke, Record, and Kennard (1931) ;Norris, Heuser, Wilgus, and Ringrose (1931); Payne, Hughes, and Leinhardt (1932);and Hunter, Dutcher, and Knandel (1931) that the occurrence of slipped tendon in growing chicks is definitely increased by an excess of calcium and phosphorus in the ration. On the other hand Titus (1932) believes that other factors of the ration being favorable "a mere excess of mineral ingredients does not cause a higher percentage" of slipped tendons.…”

“…Consequently a number of experimental studies have been conducted to determine the influence of the composition of the ration, particularly the mineral portion, on the occurrence of slipped tendon in growing chicks. Payne, Hughes, and Leinhardt (1932) observed 63 percent of slipped tendon in one experimental lot of chicks. Hunter, Dutcher, and Knandel (1931) found that by adding excessive amounts of bone meal, sodium phosphate, calcium carbonate, and various so-called balanced mineral mixtures to the experimental ration the abnormality occurred in 90 percent of their birds.…”

Inorganic Phosphorus and Perosis

“…Parkhurst and McMurray (1933) found that the occurrence of slipped tendon varied with the relative quantities of meat and bone scrap and bone meal fed. Payne, Hughes, and Leinhardt (1932) showed that a mineral mixture composed of chemically pure calcium phosphate and calcium carbonate produced the same deleterious effects as an equivalent amount of steamed bone meal. Titus (1932) concluded that rice bran contains a factor which is necessary for the normal development of bone in the case of the chicken.…”