Comparison of the Effects of Different Levels of L-Carnitine Supplementation on Growth and Egg Production in Three local Quail Lines Using In Ovo Injection and Dietary Feeding Methods

Two studies were conducted to examine the impact of in-ovo injection and dietary addition of L-carnitine (LC) on the growth and egg laying traits of three lines of local quails: desert, brown, and white. The first experiment involved 480 fertile quail eggs were utilized, on the 14th day of incubation, live embryos inside the eggs were injected in the amniotic fluid with varying doses of L-carnitine (0, 4, 8, and 12 mg dissolved in 100 L of a commercial diluent). In the second experiment, 480 one-day-old, unsexed quail chicks were divided into four experimental treatments included: The first group was given the basal diet (control), while the other groups were provided with the basal diet supplemented with different levels of L-carnitine (150, 350, and 500 mg/kg). The evaluation of statistics indicated that quail lines, in-ovo injection, and dietary supplementation with L-carnitine significantly (p?0.01) influenced all the studied traits, except for the first egg weight. The interaction between quail line and in-ovo injection treatments was only significant at age of maturity. Conversely, the interaction between the quail line and the dietary supplementation had a significant impact on feed intake, feed conversion ratio, and age at maturity. According to the present results, it can be established that both in ovo injection and dietary supplementation of L-carnitine significantly influenced the productive characteristics traits of quails. In particular, the study revealed that a high in- ovo injection dose of 4 mg/100 µL of diluent and a feed supplement at 350 mg/kg feed resulted in improved production efficiency for quail chicks, except for the initial egg weight, there was no statistically significant association between the feed addition and in-ovo injection treatments.