Findings in broiler slaughter plants
In the slaughter of broilers, the official veterinarian can evaluate the presence of several lesions during the inspection of the birds. Many of them are caused by a poor management during the catching and transportation of birds to the slaughter plants; while others are characteristic of pathological processes that are present in the farm.
Actions towards animal welfare are legislated in the Argentine Republic through SENASA, the national regulatory body, decree 4238/68, Chapter XXXII. Compliance with legislation is complicated due to the bad capturing practices in the farms and the large distances the animals have to travel to the slaughter plants. This leads to the presence of birds with traumatic processes, dehydration, hyperthermia in warm climates or freezing in cold periods, thinning and stress, which directly affect the quality of the final product.
During ante-mortem inspection, it is possible to evaluate characteristic lesions caused by the capture in the farms:
Hematomas of different colors can be observed in wings, rump, thighs and, to a lesser extent, chest; coinciding with the zones of the body the operator uses to handle the bird during the catching in the farms.
Fractured or disarticulated wings are also observable, caused by the intense flapping of the birds trying to escape from the operators.
The transport in overloaded boxes causes skin lesions due to high densities and scratches between the animals, and mortality due to asphyxiation.
Some companies practice the fasting of the birds during the travel to the slaughterhouse due to the long distances. This prevents the digestive tract from emptying, because the lack of movement and overcrowding interrupts defecation. This precise causes an increase of the faeces during the hanging of the birds. In addition, having feed in the bower increases the risk of contamination during the evisceration process in case the viscera breaks and the digestive content gets into the carcass.
In the area loading dock, veterinarians can evaluate the birds to determine, by visual inspection, if they have alterations related to pathological processes or a poor animal welfare.
In this article, we will discuss the finding of lesions that can be caused by mycotoxicosis in broilers.
The veterinarian has some specific inspection sites in the slaughterhouse. In the head extraction sector, the professionals can look for lesions related to erosions in the mouth’s mucosa, which are compatible with T2-toxin, MAS or DAS.
EROSION OF THE MUCOSA BUCAL
Lesions in the corneal layer of the muscular stomach or gizzard can also be observed. These lesions can be caused by the same mycotoxins affecting the mouth. This diagnosis will always be presumptive, since other pathologies should be discarded, other signs related to fungal toxins and feed contamination should corroborate it.
EROSION IN GIZZARD
During the inspection of viscera, the professional should observe and separate the different intestinal parts to be able to find internal or external injuries.
Hemorrhages and enteritis may be due to the ingestion of mycotoxin-contaminated feed. Fumonisins, T2-toxin, DAS and MAS can cause hemorrhages and enteritis throughout the intestine. Hemorrhages in the intestinal villi will vary when changing their orientation by combing the mucosa of the intestine with the fingers or scissors.
It is important to recognize bacterial (e. g., hemorrhages caused by Clostridium), parasitic or post mortem lesions. All of them must be written down and the farm should be informed about the possible pathologies that may be affecting the animals.
The veterinarian who performs tasks in a slaughterhouse can observe how certain types of injuries are repeated in different batches coming from the same farm, indicating the presence of endemic diseases, biosecurity failures, incorrect sanitary management, problems in the depopulation, cleaning and disinfection of the locals and in the sanitary breaks between batches.
In the inspection of viscera, it is possible to find pale and friable livers, corresponding to fat infiltration (fatty liver). Aflatoxin may be a determinant factor of this type of hepatic alteration, but there are many others such as poor quality or excess of fat in the diet, biotin deficiency, infectious pathologies, among the most common ones.
The long hours of fasting give the liver a pale appearance but it does not change its consistency. It is accompanied by an enlarged gallbladder, which can get easily broken and contaminate the carcass.
The inspection of the muscular masses is vital to evaluate the presence of petechial hemorrhages that indicate the presence of aflatoxins in feed. This evaluation can be carried out after the evisceration process or during the cutting, if it takes place in the slaughter.
The petechial haemorrhages generated by aflatoxins are related to capillary weakness and small vessel rupture. However, this finding is also a different from traumas caused during the catching process, or problems in the stunning process, septicemic processes and others. Usually, septicemic processes are accompanied by hemorrhages in fat and muscle.
Mycotoxicosis are globally present and need to be diagnosed and monitored by veterinarians. Professionals at the slaughterhouse and in the farms should work jointly to improve the quality of the final product.
Continuous training and rapprochement with producers is vital to educate and commit them to incorporate improvements in infrastructure and nutrition, and adequate management and sanitary practices on their farms. If all the involved work together, it is possible to mitigate the productive and economic damage caused by these pathologies.
SLAUGHTERING OF CHICKENS
Dra Evangelina Zárate
Minervet S.A. Veterinary Medic Professional Registration N ° 689 Mendoza, Argentina