Why is it More Difficult Each Year to Grow
the White Rock Meat Bird?
White Rock growth rates have changed dramatically over the years:
• Average weight at 7 weeks of age in 1957 – 2 lbs.
• Average weight at 7 weeks of age in 1986 – 4½ lbs.
• Average weight at 7 weeks of age in 1999 – 6.3 lbs.
• Average weight at 7 weeks of age in 2009 – 6.8 lbs.
Unfortunately, the White Rock’s increased efficiency at feed conversion has not been matched by improvements in the
bird’s cardiovascular system (heart and lungs). Simply put, too often the bird’s heart and legs just can’t keep up with the rest of its body.
The sad result is an increased incidence of flip-over disease (Sudden Death Syndrome or heart attacks), and Acities (an accumulation of fluid in the body cavity) caused by right heart failure (RHF). For more technical information on these two conditions, we can supply you with fact sheets.
Flip-over disease seems to strike the healthiest and the biggest birds – especially the males. Most will be found on their backs. It can happen as early as 3 days of age, and any time after this.
Since these birds are already stressed internally by rapid growth, they are much more susceptible to environmental stresses than are other breeds. This has made them increasingly more difficult to raise. To maximize your chances of success, we suggest the following.
FEED RESTRICTIONS: Start the chicks on 20 or 22% chick starter. Once the birds have reached 5 to 6 weeks of age, feed restriction can be used to slow down growth and promote a healthier bird. Feed what the birds can eat in 20 to 30 minutes 2 to 3 times per day. *Caution must be used, as too little feed can leave the bird malnourished. A vitamin supplement in the water should be used during feed restriction. Be sure to have enough feeders so all birds can eat at the same time. White Rocks generally take from 2-2.5 lbs. of feed per 1 lb. of live body weight.
GROWTH: The older your raise them, the more feed per pound of body weight they require. Birds may take longer to grow if given more space to move around and exercise, but may be healthier as well. If you see that your White Rocks are not growing as fast as they should, there may be a health problem.
SICKNESS: Any time you observe a snick or sneeze, or if your birds are looking droopy, you can give them a broad spectrum antibiotic powder (need a veterinarian prescription) mixed with their water. You can also use a "worming" powder/liquid to prevent worms from using up the nutrients in the feed the birds eat. Your birds will appear healthy even if they have intestinal worms, however they will not gain much weight.
LIGHTING: Start chicks with 24 hours of light for 4 days, then introduce a dark period. (Heat lamps must stay on.) When chicks reach 5 weeks of age, darkness can be increased. The period of darkness will reduce feed consumption as well as stimulate melatonin production. Melatonin is a hormone produced by the bird to help the immune system fight disease.
TEMPERATURE: Pay particular attention to the temperature guidelines in the Care and Comfort section of our website. If your birds are 5 weeks or older then add a vitamin supplement in the water when outside temperatures go above 80F / 27C. When temperatures hit 85F / 29C you can have a fan blowing directly on your birds.
AIR QUALITY: Air quality is very important in the prevention of Ascities. Poor ventilation, extreme temperatures, and spores from moldy litter can all affect the birds’ breathing. In chilly weather, it is better to supply extra heat and open a window than to subject the birds to a stuffy room with insufficient oxygen. If you have damp or wet litter/bedding, when the birds huddle together at night their body heat will react with the wet litter and cause poor air quality.
AN ALTERNATIVE: Consider raising our Rustic Ranger or Frey’s Special Dual Purpose. They won’t grow as big or as fast as the White Rocks, but you should experience lower mortality and fewer health problems. Because the Rustic Ranger and Frey’s Special Dual Purpose birds grow more slowly, many people find their meat to be firmer and more flavourful than that of the White Rock. If you have raised White Rocks in the past, then understand that the Rustic Ranger or Frey’s Special Dual Purpose will not get as big as the White Rocks.
