Abstract
The aim of this study was to verify the effect of the addition of an enzyme complex on performance (feed intake, egg production, egg weight and egg mass, feed conversion per egg mass, and feed conversion per dozen eggs), and on egg quality (% of shell, albumen and yolk, shell thickness, specific gravity, Haugh unit, yolk index, and albumen index), in medium-heavy laying hens at 28 to 40 weeks of age. A total of 240 Hy-Line Brown laying hens were used in a randomised block design with 10 replications of six birds per lot and four treatments: positive control (basal feed), negative control (with a reduction in metabolisable energy, crude protein, calcium and phosphorus), negative control + enzymes, and positive control + enzymes. The enzyme complex, composed of β-glucanases, β-xylanase, cellulase and phytase, was added to the feed at a ratio of 50 g t-1. The data were submitted to analysis of variance with the mean values compared by Tukey’s test at 5%. There was no difference in feed intake or egg weight between treatments. However, the addition of the enzyme complex to the negative control diet gave results similar to the remaining performance variables when compared to the positive control group. For the external and internal quality of the eggs, there was no difference between treatments for the variables under evaluation, except for the albumin index. It was concluded that use of the enzyme complex in the diet of medium-heavy laying hens gives a reduction in nutritional density without compromising production performance or egg quality.
Highlights
Exogenous enzymes have mainly been used to improve the digestibility of ingredients with high levels of non-starch polysaccharides (NSP), such as rye, wheat, barley and oats
Geraldo et al (2014) found that feed intake was higher in birds fed diets with low nutritent levels, with or without the addition of enzymes, indicating that the levels of enzyme supplementation were not sufficient to meet the energy requirements of the birds
Comparing the birds fed a low nutritional density diet, and supplemented or not supplemented with enzymes, those that received enzyme supplementation showed better results for egg production, egg mass, feed conversion per dozen eggs, and feed conversion for egg mass, being similar to the results found for birds that received the positive control diets with no enzymes
Summary
Exogenous enzymes have mainly been used to improve the digestibility of ingredients with high levels of non-starch polysaccharides (NSP), such as rye, wheat, barley and oats. Wheat bran is a good alternative in poultry diets and can supply up to 70% of the metabolisable energy of the diet, but the high levels of arabinoxylans (AX) in its composition restrict its use in feed for commercial poultry (O’NEILL; SMITH; BEDFORD, 2014). According to Barbosa et al (2012), enzymes can be used as nutritional strategies to generate a reduction in the nutrient level of diets and achieve a similar or better response from the birds when compared to a diet of adequate nutrient levels. This response comes from increases in the nutritional value of the ingredients due to the action of the enzyme in improving nutrient availability
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
