Zinc supplementation: its effect on egg production, feed conversion, fertility, and hatchability

Area of Science:

• Animal Science
• Poultry Nutrition
• Reproductive Biology

Background:

• Zinc is an essential trace mineral crucial for poultry health and productivity.
• Layer hen diets require adequate zinc levels for optimal egg production and chick quality.
• Previous research indicates varying zinc requirements based on diet composition and hen age.

Purpose of the Study:

• To evaluate the impact of supplemental zinc carbonate on egg production, feed conversion, fertility, and hatchability in Single Comb White Leghorn hens.
• To determine the minimum adequate dietary zinc level for commercial layer hens.
• To assess the effect of maternal zinc intake on progeny growth and feather development.

Main Methods:

• Four trials were conducted over four laying years with Single Comb White Leghorn hens (24-68 weeks of age).
• Hens were fed a corn-soybean meal basal diet supplemented with zinc carbonate at 0, 10, 20, or 40 ppm.
• Egg production, feed intake, feed conversion, fertility, hatchability, and 3-week chick body weight were measured.

Main Results:

• Zinc supplementation did not consistently improve egg production, feed intake, feed conversion, fertility, or hatchability.
• Chicks from hens fed the basal diet with 28 ppm zinc showed increased feather fraying, indicating a potential deficiency.
• No significant differences in 3-week progeny body weights were observed across treatments.

Conclusions:

• A dietary level of 28 ppm zinc, naturally present in the corn-soybean meal diet, appears adequate for supporting egg production, fertility, and hatchability in layer hens.
• Higher supplemental zinc levels did not provide additional production benefits.
• Maternal zinc status influences progeny feather development, with lower levels potentially leading to deficiency symptoms.