Early feeding with hydrogel nutrients modifies cecal microbiota, immunity, gene expression, and improves growth performance in ostrich chicks

The period extending from the final days of embryonic development until post-hatching is critical for the development of the digestive and immune systems of poultry. Therefore, early feeding programs are used to provide all the nutrients and growth factors necessary to support the maturation and integrity of the digestive system. Accordingly, this study aimed to evaluate the effect of early post-hatch feeding with hydrated nutrient gel (HNG) on growth performance, immune response, cecal microbiota, and gene expression in ostrich chicks. One hundred and fifty African ostrich chicks were divided immediately after hatching into six groups (five replicates per group) as follows: the first group was feed deprived for the first 24 h after hatching (control group, HNG0); the other groups was feed deprived for the first 2 (HNG2), 6 (HNG6), 12 (HNG12), 18 (HNG18), and 24 (HNG24) hours post-hatching, respectively (given 25 g HNG/chick). Results showed that receiving HNG2 and HNG6 groups significantly increased the body weight gain (BWG); however, the feed conversion ratio (FCR) decreased (P < 0.05). Chicks fed HNG2 and HNG6 had higher (P < 0.05) superoxide dismutase (SOD), immunoglobulin A (IgA), triiodothyronine (T3), and interleukin-10 (IL-10) contents than those fed other treated-groups and HNG0, whereas lower malondialdehyde (MDA) and interleukin-6 (IL-6) levels (P < 0.05). In the HNG2 and HNG6 groups, the Escherichia coli count significantly decreased, while the Lactobacillus count increased in chicks fed HNG2, HNG6, and HNG12 (P < 0.05). Additionally, IGF-1 gene expression was significantly increased in HNG2 and HNG6 groups (P < 0.05). In summary, early feeding with HNG can effectively improve growth performance, antioxidant capacity, immunity, cecal microbiota, and gene expression of ostrich chicks. This study presents an effective strategy for applying early HNG feeding in ostrich chicks.