Effectiveness of low sodium diets for recycling of egg production type hens.

Egg type hens were recycled by the use of low sodium diet treatments compared to a conventional forced-molt procedure and an unrecycled control. Use of a low sodium diet containing .02 to .06% sodium for 6 weeks with reduction in daily photoperiod resulted in improvements in egg production, egg specific gravity, and albumen thickness similar to those of a forced-molt group in three separate experiments. Egg production was increased 11 to 13%, egg specific gravity was increased by .002 to .004, and albumen thickness was increased by 2 to 8 Haugh units over the 32-week posttreatment period for both treatments. Hens fed the low sodium diet for 3.5 or 4 weeks did not respond as favorably as hens fed this diet for 6 weeks. Eight weeks on the low sodium diet did not further improve performance. Results comparable to the forced-molt procedure were achieved with a decline in egg production at .03 to .07% sodium in the diet, a decline in feed intake at .03 to .07% sodium, a loss in body weight at .03 to .10% sodium, and an increase in molt score at .03 to .11% sodium during the experimental period. During the posttreatment period, results comparable to the forced-molt procedure were obtained for egg production increase at .03 to .08% sodium, for egg specific gravity increase at .03 to .12% sodium, and for egg albumen thickness increase at .03 to .12% dietary sodium. Mortality was unchanged.