Nutritional imprinting and its benefits in poultry

Epigenetics or neonatal programming of poultry might soon be used to improve flock performance and reduce environmental pollution.

One way to reduce the amount of phosphorus and nitrogen in poultry waste, which ultimately reaches the environment as water and air pollution, is to feed less of those nutrients in the first place. Neonatal programming of poultry offers a potential way to do this while cutting production costs.

Epigenetic techniques being tested   

The concept being tested by researchers at the University of Maryland and North Carolina State University involves reducing certain nutrients (such as phosphorus, calcium or protein) in the diets of early post-hatch chicks for a 90-hour period. The treated, or imprinted, birds then are able to better absorb those nutrients later in life.

The researchers are now at work to adapt the epigenetic techniques that have been successful in poultry in the lab and floor-pen trials to commercial industry conditions.

Economic and environmental benefits   

“Neonatal programming allows us, without the use of phytase, to reduce the amount of phosphorus in the diet, which has both economic and environmental implications,” said University of Maryland researcher Dr. Roselina Angel.

“It would allow poultry producers to reduce phosphorus rather markedly in the feeding phases where the birds are eating the most. This is where producers are spending the most money for phosphorus in the feed and where its reduction would have the greatest environmental impact,” she said during a speech at the Midwest Poultry Federation Convention.

“If you look at the potential long-term impact in a 2.3 kilogram, or 5.5 pound, broiler, the neonatal imprinting allows for a reduction of 3.9 grams of phosphorus, which is a 28% reduction versus the control birds,” she continued.

“The limitation so far is that the research has been conducted in batteries, and the concentrations of calcium and phosphorus needed in the imprinting phase have to be very precise. Our next step is to take the experimentation to paired poultry houses to do comparison work in the field,” she said.

Dr. Angel and co-researchers have experimented with neonatal programming using calcium, phosphorus and protein. Collaborators include Dr. Chris Ashwell of North Carolina State University and others.

Required duration and level of deficiency   

Research in Dr. Angel’s lab has shown that early post-hatch chicks fed diets deficient in phosphorus and calcium for 90 hours had better total phosphorus absorption, phytate phosphorus disappearance and calcium absorption later in life than control birds.

Experiments have also shown that a 48-hour treatment does not produce the beneficial effects. The full 90 hours of treatment are necessary.

While both a moderate and low deficiency of phosphorus and calcium produced the desired effects in caged-battery settings, only the low, or more severe, deficiency worked in pen trials. It is believed this is due to chicks gaining phosphorus and calcium in their diets through the consumption of litter in the pen-trial settings. This implies that the low deficiency treatment will be needed to produce beneficial results in commercial industry conditions.

Field trials needed  

“If epigenetics is truly working, is should provide results from generation to generation,” Angel said. “So we are hoping to work with a breeding company to determine if there is an impact in the progeny of imprinted birds.

“Demonstration trials are also needed in different areas of the country and with different diets and ingredients. We need to make sure that the cost of having an additional diet is justified and that the imprinted poultry can withstand processing without losses from decreased bone ash in the skeletal system,” she said.