Excess dietary fluoride affects laying performance, egg quality, tissue retention, serum biochemical indices, and reproductive hormones of laying hens.

The present study aimed to evaluate the effects of excess dietary fluoride (F) on laying performance, egg quality, tissue retention, serum biochemical indices, and serum reproductive hormones of laying hens. A total of 384 Hy-Line Gray hens, 37 wk old, were treated with sodium fluoride added to a corn-soybean meal basal diet at 0, 400, 800, and 1200 mg fluorine/kg feed. The results showed that dietary F levels at 800 and 1200 mg/kg markedly decreased ADFI, laying rate, average egg weight, and increased feed conversion ratio (FCR) (P < 0.05). Dietary F levels at 800 and 1200 mg/kg dramatically decreased the egg quality of albumen height, yolk color, eggshell strength, and eggshell thickness, and on the 49th D, 400 mg/kg F group significantly decreased the eggshell strength, compared to those of control group. Fluoride residues in tissues of hens were increased significantly with the increase of dietary F supplemental levels (P < 0.05). Fluoride concentrations were generally high in feces, eggshell, tibia, kidney, and ovary, and the highest in feces, following with eggshell and tibia, lower in kidney and ovary, and the lowest in serum. Serum uric acid levels and alanine aminotransferase activity increased significantly (P < 0.05), and glucose, triglycerides, and phosphorus decreased significantly (P < 0.05) in response to dietary F concentration, compared to those of the control group, respectively. Dietary F supplementation at 1200 mg/kg significantly decreased (P < 0.05) the estrogen concentrations in serum, compared to those of the control group. Concentrations of progesterone in the fluoride-treated groups were significantly (P < 0.05) decreased relative to those of the control group. In conclusion, these results indicated that the excessive ingestion of F has had a detrimental effect on egg laying rate and quality of eggs by damaging the function of the liver, kidney, and ovary of laying hens.

Effects of in ovo feeding of l-arginine on hatchability, hatching time, early posthatch development, and carcass traits in domestic pigeons (Columba livia).

The objective of this research was to test the hypothesis that in ovo feeding of arginine (Arg) may improve hatchability and posthatch performance in domestic pigeons (). A completely randomized design ( = 3) with an Arg feeding treatment (Arg group, 1.14 mg Arg dissolved in 200 µL of 0.75% NaCl buffered saline as 1% concentration compared to total Arg in the egg), a buffered saline feeding treatment (SC group, 7.5 g NaCl dissolved in 1 L sterile distilled water as the concentration of poultry physiological saline), and a nonfeeding treatment (NC group) was used. Six squabs from each treatment were randomly sampled on day of hatch (DOH), posthatch d 7 (D7), and posthatch d 14 (D14), respectively. Hatchability, hatch time, BW, organ development, and carcass traits were examined. Results showed that in ovo feeding of the Arg solution increased ( < 0.05) the hatchability and advanced ( < 0.05) the hatching time in comparison with those of the other groups. Body weight of pigeon squabs that received Arg in ovo feeding was heavier ( < 0.05) on DOH and D14 than that of the NC group, and a greater ( < 0.05) BW gain from DOH to D14 and D7 to D14 was observed. Three clusters of 12 organs were classified according to the changes of organ indices. Squabs provided the Arg in ovo feeding treatment gained a priority in organ development. The heart index and gizzard index on D7 and the proventriculus index on D14 of squabs receiving Arg in ovo feeding were increased ( < 0.05) compared to those of the other groups. The brain index on DOH, the small intestine index and pancreas index on D7, and the liver index, pancreas index, and spleen index on D14 of squabs fed Arg were higher ( < 0.05) than those of the NC group. The spleen index on D7 and the small intestine index on D14 of squabs provided the Arg feeding treatment were enhanced ( < 0.05) compared with those of the SC group. The semieviscerated carcass weight of squabs receiving Arg was higher ( < 0.05) on D14 than that of other groups. The absolute weight of breast meat yield on D7 and breast meat yield percentage on D7 and D14 were improved ( < 0.05) in the Arg group compared with the NC group. The leg meat percentage on D7 and the carcass weight, eviscerated carcass weight, and absolute weight of breast meat yield on D14 were increased ( < 0.05) in the Arg group compared with those of the SC group. The results of this study indicate that in ovo feeding of pigeon embryos with Arg may have beneficial effects on squab hatch performance and early posthatch performance.