Performance of laying hens as affected by the supplementation of a barley-based diet with a crude enzyme preparation from Trichoderma viride
Two experiments were conducted to compare the performance of Leghorn hens fed a barley-based diet (68.93%) containing three levels of a Trichoderma viride enzyme supplement (0, 100 and 200 mg kg−1 as treatments T2, T3 and T4, respectively) with those obtained when fed a corn-based diet (Treatment T1). In exp. 1, 80 hens were used to determine performance during four 28-d periods, between 21 and 37 wk of age. Egg production, feed consumption, feed efficiency and egg weight of the hens were not affected by enzyme supplement and were similar to those of hens fed the corn diet (P > 0.05). There were also no significant effects on feed consumption per gram of egg or per bird per day (P > 0.05). There was a significant interaction for egg weight between enzyme addition and periods (P < 0.034), indicating that enzyme supplementation improved egg size in the early periods. In exp. 2, 20 hens were fed the same diets to measure water consumption and the ratio of water to feed consumption. Water consumption was not affected (P < 0.07) but the ratio of water to feed was significantly reduced (P < 0.0005) when enzyme was added to the barley-based diet. Water consumption in g d−1 was 172 for T1, 215 for T2, 211 for T3, and 195 for T4, and the water to feed ratios were 1.40, 1.85, 1.66, and 1.56, respectively. These results demonstrate that barley can replace corn in layer diets and that the addition of enzyme to barley-based diets appears to improve egg size and to reduce water consumption relative to feed intake in young laying hens. Key words: Laying hens, performance, water consumption, β-glucans, enzyme supplementation