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Three experiments were conducted to study the effects of crude enzyme preparations on the performance and gastrointestinal tract size of chicks fed wheat and barley diets. In the first experiment, enzyme addition (100 and 200 mg/kg of Roxazyme G and 1,000 mg/kg of Avizyme SX) to diets containing Bedford barley improved weight gain (6%) and the feed to gain ratio (5%) over a 6-wk period for both male and female broilers. In Experiment 2, enzyme addition to diets containing Scout (hulless) and Bedford (hulled) barley improved (P < or = .05) weight gains of Leghorn chicks by 25 and 11% and the feed to gain ratios by 10 and 6%, respectively. Feed consumption increased significantly (16%) only in the case of birds fed enzyme with Scout barley. Corresponding reductions in the relative weights of the crop and gizzards were 15 and 17% for birds fed Scout barley and 7 and 8% for those fed Bedford barley. Enzyme treatment of the diet containing Scout barley also reduced the relative length of the duodenum, jejunum, and ileum and the relative weight of the proventriculus, whereas a similar treatment of Bedford barley resulted in changes in the relative length of the duodenum and jejunum (P < .05). In the final broiler experiment (42 days), crude enzyme addition (100 mg/kg) to wheat and barley diets improved weight gains by 13 and 9% and feed to gain ratios by 7 and 10%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

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Concerns regarding the welfare of laying hens raised in battery cages have led to the development of enriched cages that allow hens to perform natural behaviors including nesting, roosting, and scratching. This study was conducted to compare indices of production and welfare in birds housed in 2 different caging systems. Shaver White hens were housed from 21 to 61 wk in either conventional battery cages (n = 500; 10 cages; 5 hens/cage; floor space = 561.9 cm(2)/hen) or enriched cages (n = 480; 2 cages; 24 hens/cage; floor space = 642.6 cm(2)/hen) and were replicated 10 times. Enriched cages provided hens with a curtained nesting area, scratch pad, and perches. Production parameters and egg quality measures were recorded throughout the experiment. Plumage condition was evaluated at 37 and 61 wk. Bone quality traits and immunological response parameters were measured at 61 wk, and 59 and 61 wk, respectively. Hen-day egg production, feed consumption, egg weight, and percentage of cumulative mortality of laying hens were not affected by the cage designs. Specific gravity and the percentage of cracked and soft-shelled eggs were also similar between the 2 housing systems. The incidence of dirty eggs was, however, significantly higher (P < 0.0001) in enriched cages than in conventional cages. Feather scores were similar between birds except for the wing region, which was higher (P < 0.05) for hens housed in conventional cages. Bone quality measures tended to be higher for hens housed in enriched cages compared with hens in conventional cages. However, the increase was significant only for bone mineral density. Immunological response parameters did not reveal statistically significant differences. Overall, laying performance, exterior egg quality measures, plumage condition, and immunological response parameters appear to be similar for hens housed in the 2 cage systems tested. Enrichment of laying hen cages resulted in better bone quality, which could have resulted from increased activity.

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