Key points are not available for this paper at this time.
The research aimed to investigate the impact of injecting various doses of L-carnitine (LC) into hatching eggs on reproductive characteristics, mortality, and Hatched Chicks' immunity post-hatching in two distinct broiler chicken strains on the 13th day of the incubation period. The study utilized 300 fertilized eggs collected from commercial Indian River and Ross 308 broiler breeder parent stocks aged 40-42 weeks. Eggs were randomly distributed to five treatments: T0 (Negative control), T1 (injected with 0.5 ml/egg sterilized distilled water, positive control), T2 (injected with LC 2%), T3 (injected with LC 4%) and T4 (injected with LC 6%). The results demonstrated that, for both chicken strains and their interaction, there were no statistically significant differences (p > 0.05) observed in the weight of incubated eggs and the chick: egg weight ratio among the various treatment groups. Nevertheless, the study revealed significant enhancements (p ≤ 0.01) in various parameters, including chick weight, mortality, Set egg hatchability, fertile egg hatchability, fertility, and immune response against Newcastle disease (ND) and Infectious Bronchitis (IB). The enhancements were linked to the administration of L-carnitine through ovo injection in both strains of broiler chickens. Also, the injection with 2% of LC positively influenced the percentages of fertility and hatchability, while decreasing the percentage of perished embryos. Furthermore, it was noted that the Ross 308 strain closely followed the Indian River strain in most study traits however Indian River strains exhibited significantly better survival (P ≤ 0.01) with the lowest mortality rate. In conclusion, the research found that the ovo injection of L-carnitine exhibited positive effects on hatchability traits on the 13th day of incubation for both Indian River and Ross 308 strains.
Ahmed et al. (Sun,) studied this question.