The Effect of In Ovo Injection of Organic Manganese on the Hatchability of Broiler Breeder Hen Eggs and Productivity of Offspring Broiler Chickens

This study investigated the effects of in ovo injection of organic manganese on the hatchability of eggs of broiler breeder hens. It also evaluated the performance, carcass characteristics, blood biochemical parameters, liver enzymes, immune system response and intestinal microbiota in offspring broiler chickens. For the in ovo injection, 320 fertile eggs were selected from the Ross 308 breeder hens’ flock at 55 weeks with the same average weight (65±1 g). Treatment 1: negative control group (no injection), treatment 2: positive control (injection of 0.272 mL of normal saline solution), treatment 3 (Mn20): injection of 0.272 mL of a solution containing 73.52 μg of organic manganese (20 μg for each egg), and treatment 4 (Mn30): injection of 0.272 mL solution containing 110.28 μg of organic manganese (30 μg for each egg). Hatched chicks were raised based on a completely random design, including four treatments and four replications with commercial diets based on corn-soybean meal. The results showed that in ovo injection of organic manganese led to an improvement in the hatchability compared to the positive control treatment, but the highest percentage belonged to the treatment without injection (negative control) (P < 0.05). In the whole period, no negative effects were observed on production performance, carcass characteristics and gut morphometry after injection (P > 0.05). Total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, atherogenic index, protein, albumin, globulin uric acid, creatine kinase, erythrocytes and the average volume of red blood cells of chickens increased in the groups injected with organic manganese (P < 0.05) but alkaline phosphatase decreased (P < 0.05). Birds injected with organic manganese had the lowest leukocytes and heterophils and the highest lymphocytes (P < 0.05). In addition, a reduction of coliform and Escherichia coli populations and an increase of Lactobacillus, Bifidobacterium and lactic acid bacteria after in ovo injection of organic manganese was found (P < 0.05). In conclusion, in ovo injection of organic manganese, without having a positive effect on the hatchability, had both positive and negative effects on the biochemical parameters of the blood and the immune system. Moreover, it was effective in improving the chicken’s cecal microbiota.