This article appears in the August issue of Poultry International. View all of the articles in the digital edition of this magazine.
Whether total or partial, condemnations and downgrades at the poultry processing plant affect profitability.
While some quality issues with processed chickens are improving, others are emerging, particularly where the poultry industry is working with larger or younger birds and processing is increasingly automated.
According to Dr. Sergio Vieira, associate professor at the Universidade Federal do Rio Grande do Sul, speaking at the 4th International Poultry Symposium, organized by Zinpro, to a greater or lesser degree the following conditions can be seen in the processing industry around the world.
1 Gastrointestinal contamination
Contamination of the chicken carcass can occur due to poorly managed feed withdrawal. Both overly short and overly long withdrawal periods can lead to problems, with issues including the presence of the entire gastrointestinal contents in the carcass, feed in the crop, non-digested feed at the intestine end and the spillage of bile.
Speed of passage of the intestinal contents may also be affected by pendulous crop, a growing problem that increases the risk of contamination.
Where feed withdrawal is too long, and when birds of varying sizes are automatically processed, the possibilities for bile spillage with the carcass can increase, causing major damage to the abdominal cavity and leading to the whole carcass being condemned.
2 Cadavers
While absolute numbers of poultry plant condemnations may be small globally, cadavers are, nevertheless, a widespread problem. Cadavers, when blood is still showing in the meat, are generally related to processing issues, particularly line speed.
3 Scratches
The risk of skin scratches, and consequent condemnation, is increasing. This can be attributed to birds being harvesting at an ever younger age, and as this trend increases so does the risk of skin scratches.
The physiological and anatomical condition of birds is related to their age, not size, and so as ever younger broilers are processed, the likelihood of skin breaking increases.
Various attempts have been made to address this problem through nutrition.
Broilers’ skin maturity at processing is not the only issue where scratching is concerned. Feather cover, or lack of, can increase risk, and young mail broilers have less feather cover.
Where the processing line runs high levels of birds per square meter or per second, there is also a higher risk of scratching occurring.
4 Cellulitis
Cellulitis is the end point of a scratch that has become contaminated, mostly with specific strains of Escherichia coli, and risk factors are related to the intensity and density of farm production.
Frequently, cellulitis does not show, for example when the skin has healed, only being detected at cut up. At this point, it will lead to partial condemnations. However, where whole birds are sold and cellulitis not detected, there is an increased risk that poor quality processed chickens end up in the hands of the consumer.
Often, where there are high levels of condemnations at the poultry processing plant due to cellulitis, the problem can be traced back to contamination on the farm, and lower stocking densities and healthier birds may help to resolve this.
5 Hematoma
Hematoma may occur on farm or at the poultry processing plant. It does not lead to condemnations in all countries, but meat is often downgraded for use in processed products.
As with scratches, there can be no hematoma without contact, and stocking densities and the high intensity and speed at which birds are processed are contributing factors.
6 Fractures and dislocations
Fractures and dislocation can occur during catching on farm or during hanging at processing. Age can again be a contributing factor, as younger birds need to be treated with more care.
Modern diets may be contributing to this source of poultry plant condemnations, due to lower digestibility of calcium or phosphorous, while automated processing equipment with increasing turns, and a variety of bird sizes, may also play a part.
Poor stunning can also be a contributing factor and can lead to hemorrhages and more blood being retained in the carcass.
7 Contact dermatitis
Contact dermatitis is primarily the result of poor litter condition. Litter condition is not only affected by the number of birds per square meter, but also by broilers’ diets, for example when diets are poorly digested, sticky or when the excreta contains more water.
The main part of the broiler affected is the feet, which can represent an important revenue stream in Asian markets.
With today’s bigger broiler, there is more contact with the litter, and so contact dermatitis can also affect the breast.
8 Muscle disorders
Muscle disorders, or myopathies, are increasingly occurring. Myopathies can be detected around muscles, but from a processing point of view, what is most important is when the muscle itself is affected.
The first myopathies to emerge were deep breast myopathies due to ischemia, or a lack of blood supply to the minor breast muscle. This condition is attributable to excessive compression to the vessels that irrigate the muscles, and can occur when there is an increase in wing flapping, for example at the processing plant.
Recent decades have also seen the emergence of dorsal cranial myopathy. This can be detected from the outside of the bird, and when the skin is removed. The condition is clearly evident, with exudate becoming dead cells and color change to the muscle.
9 White striping and wooden breast
Breast white striping is the first stage of wooden breast and is due to an accumulation of fat changing the color of muscle fibers. This not only changes the visual condition of breast meat, but also its physical and chemical characteristics.
With wooden breast, the number of fibers in breast meat changes. As fiber size increases, the number of fibers decreases. This is largely thought to be due to efforts to produce birds with a larger breast, which has resulted in the diameter of fibers increased, rather than fiber count.
White striping is due to the accumulation of fat in breast meat.
To learn more, read: White striping in broiler breast meat
