Determination of metabolizable energy value in Sunflower meal with and without enzymes addition by regression method in adult leghorn roosters

Document Type : Research Paper

Authors

• Ronak Zamani ¹
• Hossein Janmohammadi ¹
• Yousef Didehban ¹
• Ali Khodadadi ²

¹ Department of Animal Sciences, Faculty of Agriculture, University of Tabriz, Tabriz, Iran

² Food Hygiene, Veterinary Medicine, Islamic Azad University, Tabriz Branch, Tabriz, Iran.

Abstract

Keywords

• Regression method
• metabolizable energy
• Sunflower meal
• Enzyme
• adult Leghorn roosters

Main Subjects

• Animal Nutrition and poultry

Extended Abstract

Introduction

In the poultry industry, feed costs account for the majority of production costs, making sudden changes in feed prices challenging for nutritionists to maintain animal performance and health while managing feed costs. The first solution that comes to mind is the use of cheap raw materials when preparing food rations in practical conditions. In addition, the feed used in the diet must be digestible by the poultry in the digestive tract. Feeds such as sunflower meal (SFM) due to their high cellulose content are not digested because there is no cellulase secretion in the digestive tract. The use of several enzymes that increase the digestibility of nutrients and reduce anti-nutritional compounds such as cellulose and non-starch polysaccharides in diets with sunflower meal can positively affect performance and profitability in poultry nutrition.  The evaluation of a feed is completed by determining its nutrients and measuring its metabolizable energy. There are different methods to determine the amounts of metabolizable energy in poultry, each of which has advantages and disadvantages. The regression method is one of the methods of determining metabolizable energy, which provides the possibility of studying metabolizable energy in practical diets and at different levels. The aim of this experiment is to determine the amount of apparent metabolizable energy corrected for the zero point of nitrogen balance (AMEn) of sunflower meal with and without enzyme by regression method in adult Leghorn roosters.

Materials and methods

Sunflower meal samples were obtained from animal feed mills in East Azerbaijan, and its chemical composition was measured according to standard methods. 48 adult Leghorn roosters were used in a completely randomized design as a 2×4 factorial arrangement, two levels of enzyme ( 0 , 350 gm /kg × four levels (o, 5,10, 15 %) of SFM.   SFM was replaced in different levels in a corn - soybean meal based diet. A total of 48 adult Leghorn roosters of the W36 strain with a similar average weight (1960 ± 72) were used. The roosters were housed in individual cages measuring 40 × 45 × 40 cm with separate feeders and drinking water at the metabolic cage. The temperature was maintained in the range of 20 to 26 °C for adult roosters in the metabolic room and a photoperiod of 16 hours of light and 8 hours of darkness was used. The roosters were fed a maintenance diet during the breeding period.

A corn-soybean meal basal diet was fed to meet nutrient requirements of the roosters. The European method was used to determine apparent metabolizable energy corrected to zero point nitrogen balance in the basal and experimental diets. Adult roosters were fed the experimental diets for 9 days (four days of adaptation to the experimental diets, one day of starvation before the start of feeding experimental diet, three days of feeding the experimental diets and one day of starvation after end of the feeding period). The amount of each experimental diet consumed during the experiment was recorded and all droppings were collected and stored in plastic bags at -20°C in a freezer until chemical analysis. After removing the droppings from the freezer, they were kept at laboratory temperature for thawing and then dried in an oven at 70°C for three days. After removing the droppings from the oven, they were cooled in a desiccator and placed in the laboratory for 24 hours for moisture exchange, and then weighed with a scale with an accuracy of 3 decimal places. For chemical analysis, the dried excreta were crushed with a mortar and pestle, and the remains of feathers and scales were separated and then ground with a 1 mm sieve.

Results and discussion

The average values of DM, Ash, CP, EE, Neutral Detergent Fiber (NDF), and acid Detergent Fiber (ADF) were 88.9, 6.5, 32.33, 3.1, 44.8, 25%, respectively and gross energy value of SFM was 4547 kcal/kg.

With increasing the level of SFM in the experimental diets, the values of ADMM, AOMM, AMEn, and GE efficiency decreased significantly (p<0.05). The amount of AMEn decreased by 7.89%, equivalent to 260 kcal/kg in the diet containing 15% SFM compared to the control diet without SFM. The main effects of enzyme level caused a significant increase in AMEn values and GE efficiency of SFM (P<0.05). The equations for estimating AMEn of SFM, with and without enzyme addition were Y=2009.75-4.171X (R2=0.91) and Y=1596.14-2.414X (R2=0.91), respectively.  AMEn value of SFM with and without enzyme by regression method was estimated 1592 and 1354 kcal/kg, respectively.

Conclusions

The values obtained for AMEn of sunflower meal at the present study are recommended for formulating poultry diets and it could be probably better for predicting bird performance.

Author Contributions

 Zamani, R., Janmohammadi, H., Dedehban, Y. & Khodadadi, A. contributed to conception, design, data collection, statistical analysis, and drafting of the manuscript. All authors approved the final version for submission.

Data Availability Statement

This article contains all the data that were created or evaluated during the research.

Acknowledgements

 The authors would like to sincerely thank the members of Department of Animal Science, Faculty of Agriculture, Tabriz University for the approval and support of this research.

 Conflict of interest

 The author declares no conflict of interest.