Effect of a high fat diet fed prior to or at sexual maturity on egg weight

This study compared the effects of a low fat, high carbohydrate diet with a high fat diet fed prior to or at the onset of egg production on initial egg weight. Commercial egg-type pullets were assigned to one of three dietary regimens: 1) the control (CON), a low fat, high carbohydrate diet, 2) a high fat (HF) diet containing eight parts of fat, and 3) the high carbohydrate diet provided prelay and the high fat diet during the production period (CHO-HF). The carbohydrate prelay and laying diets contained .990 and .943% fat and had a calculated metabolizable energy (ME) value of 2,831 and 2,697 kcal/kg, respectively. The high fat prelay and laying diets contained 8.959 and 8.484% fat with a calculated ME value of 3,202 and 3,032 kcal/kg, respectively. The first 60 eggs produced by each pullet were collected and weighed. At Egg 60, no significant differences were seen in body weight and abdominal adipose tissue. The CON treatment had a significantly greater liver weight, liver lipid content, and ovary weight than the HF or CHO-HF treatments. The CON and HF treatments had a similar hen-day egg production (HDP). The CHO-HF treatment was slow to adjust to the high fat diet and that may have caused the lower HDP that was seen for this treatment. No indication of a failure to adjust to the high fat diet was noted for the HF treatment. Additionally, a high fat diet resulted in higher egg weights.(ABSTRACT TRUNCATED AT 250 WORDS)