Abstract
Fatty acid analyses and relative weights of organs from hens severely depleted of linoleic acid were made and compared with those obtained from corresponding organs from non-deficient hens. Forty essential fatty acid (EFA)-deficient Leghorn pullets were selected at 23 weeks of age and placed into 2 groups of 20 pullets each. Group 1 was fed a purified EFA-deficient diet, and group 2 was given the same diet supplemented with corn oil calculated to supply 4% linoleic acid (18:2). The control group (group 3) was composed of 20 birds selected at random from pullets fed a practical-type diet since hatching. At 23 weeks group 3 was given a practical-type diet containing sufficient corn oil to supply 4% 18:2. The hens were killed after a 32-week experimental period (55 weeks of age). Group 1 exhibited every indication of a severe EFA deficiency, namely, significantly smaller body weight, repressed egg weight and production, zero hatchability, depressed feed consumption, high mortality, and a fatty acid profile indicative of an EFA deficiency in the lipids of all organs analyzed with the exception of the pituitary. The spleen, pituitary, pineal, thyroid, and adrenals of the EFA-deficient hens weighed significantly more than corresponding organs from non-deficient hens (groups 2 and 3). This increase in weight was regarded as a reflection of the severe dietary stress imposed on the hens. The fatty acid composition of the tissue lipids from group 2 differed only slightly from that of group 3, even though egg production, egg weight, and hatchability of fertile eggs were significantly lower in group 2 as compared with that of group 3. These results demonstrated that the purified diet lacked a factor(s) other than 18:2 that was necessary for optimal reproduction.