Moy Park sees benefits in new slow growing broiler breed

Speciality free-range and extensive indoor producers now have a breed that combines slow growth with the performance associated with a regular broiler. Richard Allison reports

The free-range and speciality broiler sector is expanding rapidly, but like the conventional sector, it faces the challenge of remaining profitable when faced with high feed prices. This challenge may prove easier following the launch of a genuinely slow-growing breed.

Aviagen has spent the last 10 years developing the slow-growing Ross Rowan, which its UK breeding programme director Jim McAdam describes as “a proper broiler”. He recalls that the concept of developing a slower-growing broiler aimed at the speciality sector, which includes free-range, organic and extensive RSPCA-type indoor systems, was first floated in the late 1990s.

“We realised back then that in the near future, there would be a requirement for an alternative product to the standard fast-growing broiler.”

The company was also being encouraged by poultry producers to address the lack of a suitable slow-growing breed. Moy Park technical manager Joe Lawson says that he felt the chicks from an egg-layer type bird crossed with a broiler male could be improved upon, especially in the aspects of conformation, breast meat yield and variability in bird length.

“Processing equipment is designed around the Ross/Cobb broiler, so is unsuitable for different-shaped birds. These long birds also don’t look good on supermarket shelves with their high keel bones. Subsequently, we urgently needed a solution, as we could no longer process these birds in the factory and we wished to grow our business by establishing and expanding the windowed extensive indoor system. We also had a major customer expressing a desire to have birds with some coloured feathering.

Work started on developing the new breed and, as Mr McAdam explains, they first looked at their own genotypes and identified a slower-growing line that had been discarded from the broiler breeding programme because it had a habit of throwing out brown feathers. By 2002, Aviagen had a slow-growing line and then spent the next four years refining it.

The breed went through the same rigorous selection process as mainstream broilers to ensure robustness, good leg strength, cardiovascular function, feed efficiency and livability.

The result is the new Ross Rowan.

Ross Rowan performance


Weight (kg)

Daily Gain (g)

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Case Study: Joe Lawson, Moy Park, Northern Ireland

Moy Park has four years commercial experience with the Ross Rowan and according to technical manager Joe Lawson, the breed performs well across the company’s speciality systems – free range, organic and extensive indoor – while meeting all welfare requirements.

“It is a genuine slow-growing breed and, assuming a target body weight of 2.1kg, it meets the requirements of a minimum of 70 days for organic, a minimum of 56 days for free range and 49 days in the indoor system.

Mr Lawson adds: “Birds seem docile and very user friendly. It is a very pleasant bird to work with having good feather cover and, in our experience, adapts very well to the outdoors, especially at morning and evenings.” Mortality rates compare favourably with other breeds or are lower.

Mr Lawson believes that when compared with other slow-growing breeds in the extensive indoor system or outdoor systems, the breast meat yield of the Ross Rowan is significantly better with a more acceptable shape.

In summary, the Ross Rowan is a slow-growing bird which retains the benefits of the modern broiler including the efficient use of high prices and limited feed ingredients.

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