Publikationsdatenbank

Anatomical, histological and morphometric comparative study of the cardiovascular and the skeletal system of a male dual purpose and a broiler chicken line (2020)

Art

Hochschulschrift

Autor

Harash, George (WE 1)

Quelle

Berlin: Mensch und Buch Verlag Berlin, 2020 — II, 67 Seiten

Sprache

Englisch

Verweise

URL (Volltext): https://refubium.fu-berlin.de/handle/fub188/28201

Kontakt

Institut für Veterinär-Anatomie

Koserstr. 20
14195 Berlin
+49 30 838 75784
anatomie@vetmed.fu-berlin.de

Abstract / Zusammenfassung

Cardiovascular and skeletal diseases of rapid growing chickens are likely to be associated with intensive genetic selection for growth and feed conversion efficiency. The objective of this thesis was to assess the integrity of both cardiovascular and skeletal systems of a new genetic line of dual-purpose chickens (Lohmann Dual, LD) which was bred as an alternative to avoid killing day-old male chicks of egg-laying chickens. It should be investigated whether the LD male chickens are physically able to withstand the intensive fattening conditions. Parameters of LD should be compared to those of a highly selected fast-growing conventional broiler line (Ross 308). Eighty one-day-old male chicks of each line were housed for 5 weeks (Ross) and 9 weeks (LD). Six birds of each line were sampled weekly and the body weight was recorded. Heart mass, relative heart mass, tibiotarsus weight, tibiotarsus length and tibiotarsus width were measured. Thickness of ventricular walls, cardiomyocyte size and blood capillary density as well as aortic diameter and thickness, number of elastic lamellae and elastic fiber percentage in the aortic wall were histologically determined. Mechanical properties of the tibiotarsus (rigidity, M-Max and the M-fracture) were evaluated using the three-point bending test. Additionally, bone mineral density of both trabecular and cortical bone, bone volume fraction, trabecular number, trabecular thickness and cortical thickness of both chicken lines were analyzed using microcomputed tomography. Results showed physiologcial growth of the heart, the aorta and the leg skeleton in the LD male chickens with increasing BW. Moreover, LD male chickens seem to have more stable circulatory systems compared to conventional broilers. The assessment of the heart and the aorta showed that the heart of the LD male chickens has a larger number of blood capillaries and the aortic wall has proportionally larger numbers of elastic lamellae and more elastic fibers. This means that LD male chickens have a better myocardial capillary supply and superior aortic mechanical properties, indicating better performance characteristics of the heart and the aorta. At the same body weight of both LD and Ross chicken lines, the mechanical properties and mineral density of both trabecular and cortical bone of the leg skeleton were similar. However, LD male chickens have longer, heavier and wider leg bones than those of Ross male chickens, which results in greater rigidity. This suggests that the leg skeleton of LD chickens had more bending resistance than those of Ross chickens of the same BW. Overall, these investigations have not lead to indications that fattening the LD male chickens under the described experiment conditions to the marketable weight of 2000 g will impair the anatomical integrity of the heart, the aorta and the lower leg bone as well as the mechanical properties of the lower leg bone.