The Role of Dietary Schizochytrium Powder in Chicken Production Performance, Egg Quality, and Antioxidant Status

Three hundred and twenty 33-week-old chickens with similar egg production rates and body weights were selected and randomly divided into four groups, with five replicates each and 16 hens in each replicate. The control group (Group I) was fed a corn-soybean meal basal diet, while the test groups were supplemented with 0.5% (Group II), 1.0% (Group III), and 2.0% (Group IV) Schizochytrium powder on top of this basal diet, respectively. The pretest period was 1 week, and the main test period was 8 weeks. The results revealed the following: (1) Compared with Group I, the average daily feed intake (ADFI) and laying rate (LR) were significantly lower (<i>p</i> < 0.05) in Group IV, and there was no significant difference (<i>p</i> > 0.05) in the ADFI and LR between Groups II and III. (2) Compared with Group I, the eggshell strength (ES) and docosahexaenoic acid (DHA) content of Groups II, III, and IV were significantly higher (<i>p</i> < 0.05). (3) Compared with Group I, serum triglyceride (TG) content was significantly decreased (<i>p</i> < 0.05), and serum low-density lipoprotein (LDL) content was significantly increased (<i>p</i> < 0.05) in Groups II, III, and IV. Serum total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and peroxidase (PO) activities were significantly higher (<i>p</i> < 0.05) and serum malondialdehyde (MDA) content was significantly lower (<i>p</i> < 0.05) in Groups II, III, and IV compared to Group I. In conclusion, adding Schizochytrium powder to the feeding ration could affect chickens' production performance, increase egg DHA content, and improve the antioxidant capacity of the organism. Based on the results of this study, we recommend a ratio of 1.0% Schizochytrium powder addition.