Publication Database

Investigation of the prevalence of pathological carcass alterations at the processing plant in fattening turkeys reared in organic farming system in Germany (2021)

Art

Hochschulschrift

Autor

Freihold, Darja (WE 15)

Quelle

Berlin: Mensch & Buch Verlag, 2021 — II, 65 Seiten

Sprache

Englisch

Verweise

URL (Volltext): https://refubium.fu-berlin.de/handle/fub188/31632

Kontakt

Nutztierklinik: Abteilung Geflügel

Königsweg 63
14163 Berlin
+49 30 838 62676
gefluegelkrankheiten@vetmed.fu-berlin.de

Abstract / Zusammenfassung

The growing demand for organic products in Germany has led to an increase in organic poultry farming. Expectations of a better health status in turkeys reared in organic farming system are not always fulfilled and animal welfare related health problems still commonly occur. The monitoring of animal welfare indicators at the slaughterhouse is an important tool in order to be able to improve the husbandry and management deficiencies in further flocks. The aim of this study was to investigate the prevalence of pathological carcass alterations as animal welfare indicators at the processing plant in fattening turkeys reared in organic farming system in Germany. The investigations were carried out between July 2015 and May 2016 at three different turkey slaughterhouses in Germany. In total, 1860 turkey carcasses originating from 12 organic farms were investigated. Seven farms reared hens of the heavy weighted British United Turkey B.U.T. 6 and Test Product TP 7. In addition, five farms reared both sexes of the medium weighted Kelly Broad Breasted Bronze (Kelly BBB). From each slaughtered flock a random sample of 60 birds was investigated for the following parameters: foot pad dermatitis (FPD), breast skin lesions, liver alterations and swelling of the hock joint. The assessment of the foot pad dermatitis was performed using a five-grade scoring system (Score 0: unaffected; Score 1: necrosis of superficial scales; Score 2: necrotic lesions < 2 cm; Score 3: necrotic lesions > 2 cm; Score 4: plantar abscess). The results showed that 97.7 % of all examined turkeys suffered from different degrees of FPD. Only 1.3 % of the hens and 4.6 % of the toms showed unaffected foot pads (Score 0). 64.3 % of all turkeys had necrotic lesions < 2 cm (Score 2). Necrosis of superficial scales (Score 1: toms: 11.3 %, hens: 7.6 %) and necrotic lesions > 2 cm (Score 3: toms: 29.8 %, hens: 12.4 %) were less common. Plantar abscesses (Score 4) were rarely observed (1.9 %). In general, the foot pads of Kelly BBB hens were more affected than those of Kelly BBB toms. Compared to B.U.T. 6/TP 7 hens both sexes of Kelly BBB showed more severe lesions (Score 3 and 4), but also more unaffected foot pads (Score 0). The examination of the breast skin was done by means of a binominal score (yes/no), including breast buttons, hygromas and purulent inflammation of the bursa sternalis. In general, breast skin lesions were a rare finding in all examined turkeys (1.7 %). In total, only 30 turkeys showed the following alterations: 27 breast buttons, two hygromas and one purulent bursitis. Toms were significantly more affected than hens. Liver alterations were also assessed using a binominal score (yes/no). The external investigation covered green liver discoloration, necrosis, swelling of the liver, fatty liver degeneration and abscesses. Nearly half of all investigated turkeys were affected (49.3 %). Green liver discoloration was the most frequently detected alteration (29.8 %). Kelly BBB hens were significantly more often affected than B.U.T. 6/TP 7 hens. The prevalence of liver necrosis was significantly higher in B.U.T. 6/TP 7 hens (17.3 %) than in Kelly BBB hens (4.6 %). Furthermore, 15.9 % of all investigated turkeys showed swelling of the liver tissue, 8.6 % showed fatty liver degeneration and only 1.4 % had liver abscesses. The external examination of the hock joint revealed a swelling in 17.3 % of all examined turkeys using a binominal score (yes/no). Toms were significantly more affected than hens (toms: 28.7 %, hens: 16.9 %). Carcass alterations are a major animal welfare concern in fattening turkeys reared in organic and/or in conventional production system. In order to detect problematic farms and to evaluate the status quo, the examination of animal welfare indicators has been proven to be beneficial. Alterations such as FPD and breast skin lesions are suitable indicators. Examinations are easy to perform under field conditions using a standard scoring system. On the other hand, liver changes are also a further suitable indicator for animal welfare. They reveal valuable information about the birds’ health, however, standardized investigations are not easy to implement at the slaughterhouse. Furthermore, the external investigation of the hock joints is also not sufficient to diagnose arthritis and to draw conclusions about husbandry conditions. Investigating the prevalence of animal welfare indicators provides the necessary precondition in order to establish a standard monitoring embedded in a benchmarking system. This allows to evaluate and compare the farms and consequently to assess the need of management intervention and the success of already implemented measures.