Evaluation of the Use of Fermented Sunflower Meal in the Diet on Growth Performance, Ileum Microbial Population and Blood Indices in Broiler Chickens

Introduction : 

Sunflower meal is considered as an attractive alternative to soybean meal due to its adaptation to dry and temperate climates as well as its lower anti-nutrient content than other oilseeds. Sunflower meal has a limiter that restricts its use in broiler diets. The fiber in sunflower meal has limited its use in the diet of broilers due to reduced metabolic energy as well as production. Fermentation, which uses beneficial microorganisms, can reduce the chemical composition of the feed and increase the yield of broilers by producing enzymes and using fiber as a feed source. In this study, in order to investigate the effect of fermentation on sunflower meal, growth yield, microbial population composition, blood parameters in broiler chickens were performed.

The research was conducted at the research farm of Sari University of Agricultural Sciences and Natural Resources in 2020. In this study, 200 commercial male Ross 308 broilers were used in a completely randomized design with five treatments, five replications, and eight chickens per replication. The treatments included: 1) Control diet, 2) Diet containing sunflower meal (negative control), 3) Diet containing sunflower meal fermented with Aspergillus Oryzae, 4) Diet containing sunflower meal fermented with Penicillium Funiculosum, and 5) Diet containing sunflower meal fermented with Aspergillus Oryzae and Penicillium Funiculosum. Sunflower meal was obtained from Behpak Behshahr (Mazandaran) company, ground in the animal nutrition laboratory of Sari University of Agricultural Sciences and Natural Resources, and sieved to a size of 2 mm. Aspergillus Oryzae (PTCC5010) and Penicillium Funiculosum (PTCC5301) were purchased as lyophilized vials from the Fungus and Bacteria Collection Center of the Iranian Research Organization for Science and Technology (IROST). During the fermentation process, 1.1 liters of the mixture of distilled water and primer culture (containing at least 105 colony forming units per ml) was added to each kilogram of sunflower meal, and the resulting mixture was thoroughly mixed by hand for 15 minutes. The mixture was fermented in special tanks (with a one-way valve to remove the produced gases and prevent air from entering) for 7 days at 30 °C, and finally, the fermented sunflower meal was dried for three days at room temperature. All chickens were kept under the same breeding conditions during the 39-day period and had free access to feed. Experimental diets were adjusted to three periods: initial (1-10 days), growth (11-24), and final (25-39) using Table 1 of the Ross 308 Catalog of Nutritional Requirements for Broilers. The pH of fermented sunflower meal was determined using the Chiang et al. method. Sunflower meal was sampled before and after fermentation to measure dry matter, ash, crude protein by the Kjeldahl method, crude fat by Soxhlet device, and insoluble fibers in acidic detergent and neutral detergent using a fibrotec device. Total amino acid was measured by the ninhydrin method. Soluble sugar was measured by the intron method. Total phenol content was measured using the Folin-Siocalcu reagent and spectrophotometry. Soluble proteins were measured by the Bradford method.

During the fermentation of sunflower meal, pH, crude fat, soluble protein and soluble sugar decreased. The amount of crude protein, total amino acid, insoluble fiber in acidic detergent, and insoluble fiber in neutral detergent increased. In the whole breeding period, body weight gain was improved in treatments fed with fermented feed. In the treatment of Aspergillus Oryza + Penicillium funiculosum, feed consumption decreased compared to control, negative control and Penicillium funiculosum treatments. The feed conversion ratio increased in the negative control treatment at the age of 1-39 days compared to other treatments. In the ileum, coliform bacteria decreased in negative control treatments, Aspergillus Oryzae, Aspergillus Oryzae + Penicillium funiculosum compared to the control treatment, but Penicillium funiculosum treatment increased compared to other treatments. At 39 days of age, the use of fermented and raw feed increased the level of HDL-c in the negative control and Aspergillus Oryzae + Penicillium funiculosum treatments. The amount of LDL-c increased in the treatments of Aspergillus Oryzae and Penicillium funiculosum

Based on the results, the use of fermented feed in the feeding of broiler chickens during the entire breeding period has improved weight gain and feed conversion ratio.