Sunflower meal may offer low-cost soybean replacing feed ingredient for laying hens

A team of researchers from the Universidade Federal Rural do Semi-Árido in Brazil investigated the use of sunflower meal as a lower-cost, replacement ingredient for soybean meal in poultry feed. The group published their findings in the Journal of Animal Feed Science and Technology​.

“The objective of this study was to evaluate the performance, egg quality and economic viability of Naked Neck laying hens fed with different levels of substitution of soybean meal protein with sunflower meal, supplemented with synthetic amino acids,”​ the researchers said.

The team found that there were no major differences in the eggs laid by hens getting increasing amount of the alternative, less expensive ingredient, the researchers said. However, egg yolk color was altered.

“The partial replacement of protein of soybean meal with sunflower meal supplemented in diets for Naked Neck hens maintained productive performance and improved the yolk color, proving sunflower meal be an economically viable food alternative,”​ said the researchers.  

Why sunflower meal​

Semi-intensive poultry production offers birds a larger area and access to grazing, said the researchers. However, it also looks to reduce the cost of production while meeting consumer demands.

Corn and soybean meal used in poultry feed accounts for most of the total production cost, they said. Finding alternative feed ingredients could help reduce those expenses – especially for producers in regions of Brazil where soybean meal is particularly expensive.

The by-product of vegetable oil extraction, sunflower meal is cheaper than soybean meal and has a “protein rich in sulfur amino acids,”​ the researchers said. But, it does have lower levels of lysine and threonine, a higher fiber concentration and potentially variable chemical composition depending on processing method.

There have been inconsistent results in past experiments seeking to use sunflower meal in poultry diets, they said. More research is needed to determine the ingredient’s potential use in feed with naked neck laying hens.

“Shi et al. (2012) showed no negative influence of sunflower meal inclusion on egg production and quality of commercial hens,”​ said the researchers. “However, Junqueira et al. (2010) found that the inclusion of sunflower meal interferes with the egg quality of laying hens of the Isa Brown line.”​

Trial details​

In the study, 128 hens were given one of four diets, said the researchers. The diets were formulated to meet requirements for a semi-heavy laying hen and included a control diet and that feed with 10% (R10), 20% (R20) or 30% (R30) of the soybean meal replaced with sunflower meal and proper synthetic amino acid supplementation.

Hens also had access to 100 g/hen/day elephant grass in a free-range system, they said. Diets were fed for 15 weeks.

Eggs were collected and identified twice a day to establish laying rate and egg weight, they said. Egg mass and feed conversion per egg mass were calculated.

Selected eggs were checked each week for qualitative signs including yolk weight, albumen weight, shell weight and yolk color, said the researchers. Ingredient prices for the diets also were compared using costs in US dollars.

“One parameter of the evaluation was the economic feasibility of the inclusion of sunflower meal in feeds,”​ they said. Total revenue, additional revenue, total cost of food, additional cost, additional profit, equilibrium point and the profitability index also were established.

Results ​

The substitution of soybean meal with sunflower meal at any of the levels did not alter the hens’ laying rate, egg mass, food intake, feed conversion or egg weight, the researchers said.

The feed conversion per egg mass and feed conversion per dozen eggs favored the use of sunflower meal in the diet as a price difference was found, they said. “As the replacement of 30% of the protein from soybean meal with sunflower meal showed higher egg mass and slightly higher production values, the superiority of this diet in terms of the price of feed per number of eggs produced was proven,”​ they added.

The cost per hen per day ranged from $0.076 to $0.069 for the birds on the control diet to those getting the R30 feed, they said. The total revenue went from $517.34 for the control diet to $555.04 for R30.  

“There was no significant effect of sunflower meal level on the egg quality parameters, with the exception of yolk color, which showed increasing linear effect of protein replacement levels of soybean meal by sunflower meal,”​ the researchers said. The lipid amount in the sunflower meal may be responsible for the greater yolk color in birds getting larger amounts of that feed ingredient, they added.

Source: Animal Feed Science and Technology​

Title: Sunflower meal as a nutritional and economically viable substitute for soybean meal in diets for free-range laying hens​

DOI: published online before print: 10.1016/j.anifeedsci.2016.07.015​

Authors: Vanessa Raquel de Morais Oliveira, Alex Varela de Arruda, Ligiane Silva, João Freire de Souza, João Fernandes de Queiroz, Aurora da Silva Melo, José Holanda