Genetic differences in serum cholesterol in chickens

Abstract

Studies were conducted on the underlying mechanism for differences in serum cholesterol in two lines of chickens. The serum level of free and combined cholesterol was higher in the high line than the low line; no significant differences were observed in the serum level of fatty acids or phospholipids. The lines did not differ in the weights of several organs or in the cholesterol level of the adrenal, liver, brain, or testis. The high line had a higher serum cholesterol level than the low line, from hatching to 16 weeks of age. The lines did not differ in their response to fasting, which makes it improbable that a dietary influence accounts for the line differences. They responded similarly to injections of testosterone, estrogens, cortisone, or thyroxin.

Response to Five Generations of Selection for Blood Cholesterol Levels in White Leghorns

“…The apparent association between cholesterol levels and livability may have been caused by starvation just before death, because fasting can cause elevated cholesterol levels (Hardy et al, 1962). Voluntary reduction of food intake is commonly associated with a pathological condition, and a prominent characteristic of the birds that were diagnosed as dying from Marek's 196719681969197019711972Females, Rearing period 196719681969197019711972Females, Laying period 196719681969197019711972 Positive difference indicated a higher cholesterol value in birds that died than in birds that survived.…”