Performance of Silver Montazah Hens Fed Mash or Pelleted Diets Containing Corn-With-Cobs Meal With or Without Enzyme Supplementation

Abstract

A factorial experiment (4×2×2) was conducted to evaluate the response of laying hens to feeding experimental diets containing graded levels of corn-with-cobs meal (0, 10, 20 and 30%) with or without Kemzyme ® supplementation (0 and 1 g/kg diet) in the form of mash or pellets. Thus, 16 isocaloric and isonitrogenous diets were formulated and used from 28 to 52 weeks of age. A total of 384 Silver Montazah laying hens were randomly chosen, individually caged in an open sided house and exposed to a daily photoperiod of 16 hr, and managed similarly. All hens were fed their respective experimental diets and had free access to water throughout the experimental period. The most important results obtained could be summarized as follows: Dietary level of corn-with-cobs meal (CCM) had no significant effects on body weight change, feed consumption, egg weight, egg shape index and yolk index or serum total protein, albumin, calcium, inorganic phosphorus, or activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in blood serum of hens. Increasing dietary level of CCM positively affected feed conversion, egg production rate and egg mass. In addition, Haugh units and serum and egg cholesterol were significantly increased when the level of CCM reached 30%. However, neither dietary enzyme supplementation nor diet form (mash vs. pellets) had significant effects on body weight change, feed consumption, feed conversion, egg production rate, egg weight, egg mass, shell thickness, egg shape index, yolk index, Haugh units or egg cholesterol, or serum levels of total protein, albumin, cholesterol, calcium, inorganic phosphorus, and activity of ALT and AST in blood serum. According to the obtained results, corn-with-cobs meal can be included up to 30% in diets of Silver Montazah laying hens, without compromising their productive performance or egg quality, with no need for pelleting the diets or adding exogenous enzymes.