In-ovo feeding offers potential gains

Over 2,000 delegates attended the recent Alltech animal health and nutrition symposium in Lexington, Kentucky, USA. Scott Casey was also State-side

Poultry nutrition is increasingly becoming about pushing the boundries of science, and researchers in the USA have unveiled a novel plan to start feeding chicks before they have even hatched via an in-ovo injection of nutrients.

“Most people think the first meal the chick consumes is when it hatches, but in-fact the first meal is when that embryo consumes the amniotic fluid as it hatches,” Dr Peter Ferket, researcher at North Carolina State University told the 2011 Alltech symposium.

“The idea of taking the amniotic fluid, and supplementing it is kind of like taking corn and soy and adding minerals to it. This mix of bioactive compounds, vitamins and minerals enhances intestinal gene expression and changes morphology. It starts off a whole host of things such as the colonisation of the gut with microflora and helps those cells proliferate.”

Dr Ferket said that in his research Ross broilers had shown a 492% increase in skeletal cells and therefore strength in chicks, an 8.3% increase in breast muscle size by 10 days post-hatch and improved leg symmetry.

Under the technique, the eggs are injected with the feed mix at about 17 to 18 days of age, shortly before birds begin piping and at the time they absorb the amniotic fluid.

“During the process of hatching the glycogen stores are consumed, leaving less carbohydrate available for that very important development later,” said Dr Ferket. “To rebuild those glycogen reserves, that chick needs to extract or produce glycogen by gluconeogenesis, basically consuming his own muscle protein.”

As well as providing general nutrients, in-ovo feeding occurs at a critical point in the development of the chick, in-between the end of the development of foetal myoblast cells and the start of adult myoblast development, which determine future growth.

These adult satellite cells contribute to the ability for the chick to develop larger breast muscle later on, and when fed in-ovo, seven days after hatch, there are 500% more of these cells.

“These cells contribute to the muscle fibre. They produce the DNA which synthesises protein, so the potential for muscle fibre thickness is greatly enhanced,” Dr Ferket said.

By treating birds in-ovo, Dr Ferket believes there is a great opportunity to improve genetic expression as well as the development of the birds.

“We have a chance to take the genetic profile and activate certain types of genes to create a whole new response. This is the exciting thing about perinatal nutrition. We have the ability to possibly programme an animal to respond in a very different way.”

Dr Ferket has also worked with Dr Zehava Uni from the Hebrew University of Jerusalem to asses the impact in-ovo feeding has on gene expression. Feeding amino acids, salts, carbohydrates and hydroxy methylthiobutanoic acid (HMB), typicially used to prevent intestinal pathogens, was found to promote gene expression involved in the development of metabolic pathways, the intestine, breast muscle and liver function.

Feeding a soluable mannanoligosaccaride saw messenger RNA cells, which carry the blueprints for building protiens, increase by three times in in-ovo fed birds, with intestinal villi 20-30% longer and goblet cells, which produce mucus in the gut, 20-50% more common than in untreated birds.