Comparison of the frequency of patho-anatomic findings in laying hens with findings in broiler chickens and turkeys detected during post-mortem veterinary inspection

Abstract

We have investigated the health condition of laying hens on the basis of patho-anatomic findings obtained during the veterinary inspection after slaughter. To assess the severity of the health condition of laying hens, we compared the incidence of findings with the findings in broiler chickens and turkeys. In the period from 2010 to 2017, 17,346,183 laying hens, 887,994,167 broiler chickens, and 919,843 turkeys were transported from Czech farms to slaughterhouses in the Czech Republic. The competent veterinary authority in the Czech Republic (the State Veterinary Administration) carried out a veterinary inspection of these birds slaughtered in the slaughterhouse and recorded the patho-anatomic findings. From the recorded data, the number of patho-anatomic findings (intravital origin) of the organs and parts of the bodies (liver, intestines, lungs, heart, spleen, genital tract, urinary system, CNS, skin, head, body, limbs, and whole animal) were analysed. We found increased patho-anatomic findings in the liver (26.76%) and limbs (6.03%) in hens, and also high numbers of findings in the category of total findings (1.57%) were detected. In liver findings, chronic findings (22.09%) were prevailing over the acute findings (4.67%), compared to broiler chickens (chronic 0.04%, acute 0.03%) and turkeys (chronic 1.90%, acute 0.00%). The differences between hens, broilers, and turkeys were significant (P < 0.001). The incidence of traumatic, chronic, and acute findings in hens (3.88%, 1.71%, and 0.44%, respectively) was higher (P < 0.001) in the case of the legs, compared with broiler chickens (0.02%, 0.08%, and 0.02%, respectively) and turkeys (0.27%, 0.23%, and 0.05%, respectively). The results show that the health condition of laying hens is significantly worse than in case of broiler chickens and turkeys, especially in the impact on the liver due to the likely effect of nutrition not corresponding to the intensity of the production of laying hens, and the impact on the limbs due in particular to traumatic changes caused by inappropriate transport handling and inadequate conditions (especially cage housing) of laying hens.