Original scientific paper

Pathological changes in the liver and thyroid in broiler chickens fed by rapeseed cake.

Branka Artuković ; Department of Veterinary Pathology, Faculty of Veterinary Medicine, University of Zagreb, Croatia
Dalibor Bedeković orcid.org/0000-0002-7418-3968 ; Department of Animal Nutrition, Faculty of Agriculture, University of Zagreb, Croatia
Jasna Pintar ; Department of Animal Nutrition, Faculty of Agriculture, University of Zagreb, Croatia
Marina Tišljar ; Poultry Center, Croatian Veterinary Institute, Zagreb, Croatia
Ivica Kos orcid.org/0000-0002-2126-2566 ; Department of Animal Science and Technology, Faculty of Agriculture, University of Zagreb, Croatia
Ivan Širić orcid.org/0000-0003-0560-181X ; Department of Animal Science and Technology, Faculty of Agriculture, University of Zagreb, Croatia
Krešimir Severin ; Department of Forensic Veterinary Medicine, Faculty of Veterinary Medicine, University of Zagreb, Croatia
Zlatko Janječić orcid.org/0000-0001-9161-024X ; Department of Animal Nutrition, Faculty of Agriculture, University of Zagreb, Croatia

Abstract

The aim of this study was to investigate pathological changes in the liver and thyroid gland, to determine the possibility of using different levels of rapeseed cake in diets for chickens. The experiment was carried out on three hundred and sixty day-old male Cobb hybrid chickens, were fed by three different feeding regimens (T-0 = %; T-5 = 5 %; T-10 = 10 % of rapeseed cake, “double low” cultivar Bristol). The rapeseed cake contains 2.86 μmol/g of glucosinolate (Gls) and the ratio of erucic acid was 0.08 % of total fatty acids. Introduction of 5 % rapeseed cake to chicken feed increased mortality, but it was still an acceptable mortality rate. The average liver mass increased in groups T-5 and T-10 compared to the control group. The thyroid glands of the treated animals showed no significant increase in weight compared to the control group. Histopathologically, liver and thyroid lesions were more prominent in treated animals compared to the control group. In the treated group a significantly higher rate of perivascular necrosis of hepatocytes, and perivascular mixtocellular cell infiltration in the liver was found in the T-5 group. In the liver, there was a significantly higher rate of congestion, degeneration of blood vessels, vasculitis, and hydropic degeneration in the T-10 group. The thyroid glands of the treated animals showed a significantly higher rate of scattered proliferation of follicular epithelial cells, and mild interstitial fibrosis in the T-5 group. Severe interstitial fibrosis was pronounced only in the T-10 group, with a significantly higher rate. The highest rate of follicular haemorrhages was found in the T-10 group, followed by the T-5 group. The relation between these rapeseed cake specific changes, and the undesirable effects specific to rapeseed cake remain to be elucidated. However, the existence of causative factors other than erucic acid and glucosinolates cannot be excluded. In conclusion, the introduction of 5 % and 10 % rapeseed cake (Bristol-“double low” cultivar) to broiler chickens caused liver and thyroid changes, but these changes were not severe enough to have any major impact on production results.

Keywords

rapeseed cake; broiler chickens; liver; thyroid gland; pathological changes

Hrčak ID:

149985

URI

https://hrcak.srce.hr/149985

Publication date:

9.12.2015.

Article data in other languages: croatian

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