RESUMEN
This study aimed to assess impacts of early in ovo injection (at 10 days of incubation) of copper (sulfate, acetate, or nanoparticles) on histomorphometric parameters of small intestine and growth performance of post-hatched chicks. Fertile eggs (n = 462) were distributed to seven groups (3 replicates, 22 eggs in each). The first group as a control, the 2nd, 3rd and 4th groups injected with 100 µL deionized water containing 8 µg/egg of Cu (sulfate, acetate and nanoparticles, respectively), and the 5th, 6th and 7th groups injected with 100 µL deionized water containing 16 µg/egg of the same Cu sources above. Results illustrated that in ovo administration of Cu sulfate and Cu acetate significantly improved histological parameters of small intestine parts of newly hatched chicks compared with the control. Cu sulfate and nano-Cu significantly augmented body weight gain compared with the control. In ovo Cu injection showed a nonsignificant improvement in feed conversion ratio. The highest level (16 µg/egg) of different sources was better than the lowest level (8 µg/egg) in most results. In conclusion, it is recommended that in ovo injection of Cu (16 µg/egg) can improve the growth performance (Cu sulfate and nano-Cu) and the small intestine histomorphometry parameters (Cu sulfate and Cu acetate) of broiler chicks.
