Influence of In-ovo Injection of Organic and Inorganic Salts of Copper, Zinc and Their Combination on Post-Hatch Growth, Immune Response, Organ Development and Gut Morphology of Two Strains of Broiler Chickens
In-ovo feeding is an innovative strategy for delivering nutrients and bioactive compounds directly to the developing avian embryo to enhance post-hatch performance. This study evaluated the influence of in-ovo injection of organic and inorganic salts of copper (Cu) and zinc (Zn) and their combinations on post-hatch growth performance, cell-mediated and humoral immune responses, organ development and gut morphology of two broiler strains. A 2×7 factorial arrangement was used comprising two strains (Arbor Acre and Cobb 500) and seven in-ovo treatment groups (Control, organic Zn, organic Cu, inorganic Zn, inorganic Cu, organic Zn+Cu and inorganic Zn+Cu). Eggs were injected on day 18 of incubation with 0.1 ml of treatment solution per egg. Results revealed significant (P<0.05) strain differences in growth performance, with Arbor Acre achieving higher final body weight (1,687.60 g/bird) and average daily weight gain (33.45 g/bird/day) compared to Cobb 500 (950.60 g/bird; 25.31 g/bird/day). In-ovo injection with inorganic Cu yielded the highest feed intake across treatments. Humoral immune response was significantly (P<0.05) influenced by both strain and in-ovo treatment; organic Zn, organic Cu, organic Zn+Cu and inorganic Zn+Cu maintained antibody titres comparable to the control, while inorganic Zn and inorganic Cu individually resulted in markedly reduced titres, particularly in Cobb 500. Cell-mediated immunity was not significantly affected by strain or in-ovo treatment. Organ development parameters were similarly influenced by strain and mineral form. These findings demonstrate that in-ovo mineral supplementation outcomes are strain- and mineral-form-dependent, with organic chelated forms offering immunological advantages over inorganic sulphate salts in broiler production.
Keywords: Trace minerals, In-ovo feeding, Broiler strain, Growth performance, Immune response, Gut morphology
