Short-Term Incorporation of Tomato Pomace and Invert Sugar in Diets of One- and Two-Year-Old Layers

Abstract

By-products - tomato pomace (TP) and powdered invert sugar (IS, to enhance palatability) - were substituted at low concentration in commercial Layena^® crumble(L) diets of second and third cycle laying hens to simulate feeding of backyard layers for 2 wk. to determine the effect on several production measurements.  In Experiment I, 1-yr-old layers were fed L as the control, LTP (90.0% L plus 10.0% ground TP) or LTPIS (90.0% LTP plus 10% powdered IS).  Feed consumption was similar (p < 0.05) across diets and hens fed L maintained BW for 2 wk in contrast to those fed LTP and LTPIS.  Hen-day production for L, LTP and LTPIS was similar (P < 0.05) while yolk color for eggs from hens fed TP was significantly (P < 0.05) darker than that of eggs from hens fed L.  Egg shell thickness values for all eggs in Experiment I were similar (P < 0.05).  To compare the form of diets containing TP, in Experiment II, 2-year-old hens were fed LTP as the control or diets that were pelleted, then crumbled (LTPp or LTPISp). Hens fed LTP did not maintain BW for 2 wk while those fed LTPp had BW equal (P < 0.05) to that of their initial BW by the end of wk 2.  Hens fed LTPISp maintained BW for 2wk. Pellet formation caused statistically (P < 0.05) lower yolk color compared to that from eggs of hens fed LTP. Age and strain of hens produced low hen-d egg production of 20 to 30 %, likely obfuscating the effect of diet.  Egg shell thickness values for eggs from hens given LTPp met the standard (33 mm) while that (32 mm) for eggs from hens administered LTP and LTPISp did not. Older layers will need excess supplemental calcium when fed pellet-crumble diets with TP at 10.0%.  Pellet formation will add extra cost to backyard production and negatively affect consumer preference for darker yolks.