Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: shell microstructure

Sortuj według:

Ogranicz wyniki do:

Shell microstructure and hatchability of turkey eggs

100%

Mroz E., Michalak K., Faruga A., Horbanczuk J. O., Orlowska A.

Animal Science Papers and Reports

2008

tom 26

nr 2

The study aimed at determining the hatchability of turkey eggs as related to the shell surfach characteristics (regular shells, rough shells and pigment-spotted shells – group 1, 2 and 3, respectively). A total of 17 590 eggs of Broad-breasted White Turkeys, marked individually, were considered during the peak of the laying season. Shell microstructure was examined of 60 eggs from each group, using a scanning electron microscope while hatchability was estimated based on fertilization rate, percentage of dead embryos and hatching rate (healthy poults only).The main differences between the shells from group 1 and 2 included different size of cuticular plates, thicker crystal layer, thinner palisade and mammillary layers, curved walls of the mammillae, and thicker fibres of the inner shell membrane. Eggshells from group 3 showed a significantly thicker crystal layer and curving fibres of the inner shell membrane compared to group 1 shells.The hatching rate of set eggs was highest (77.15%) in group 1. Embryo mortality rates were by 4.9 and 5.4 per cent points higher in eggs from groups 2 and 3, respectively, than in eggs from group 1.The hatchabilities of rough-shelled eggs (group 2) and eggs with pigment spots (group 3) appeared lower than of eggs with regular shells (group 1).

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

New Barremian rhynchonellide brachiopod genus from Serbia and the shell microstructure of Tetrarhynchiidae

67%

Radulovic B., Motchurova-Dekova N., Radulovic V.

Acta Palaeontologica Polonica

2007

tom 52

nr 4

A new rhynchonellide brachiopod genus Antulanella is erected based on the examination of the external and internal morphologies and shell microstructure of “Rhynchonella pancici”, a common species in the Barremian shallow−water limestones of the Carpatho−Balkanides of eastern Serbia. The new genus is assigned to the subfamily Viarhynchiinae, family Tetrarhynchiidae. The shell of Antulanella is small to rarely medium−sized, subglobose, subcircular, fully costate, with hypothyrid rimmed foramen. The dorsal euseptoidum is much reduced. The dental plates are thin, ventrally divergent. The hinge plates are straight to ventrally convex. The crura possess widened distal ends, rarely raduliform or canaliform. The shell is composed of two calcitic layers. The secondary layer is fine fibrous, homogeneous built up of predominantly anisometric anvil−like fibres. Although data on the shell microstructure of post−Palaeozoic rhynchonellides are still incomplete, it is possible to distinguish two types of secondary layer: (i) fine fibrous typical of the superfamilies Rhynchonelloidea and Hemithiridoidea and (ii) coarse fibrous typical of the superfamilies Pugnacoidea, Wellerelloidea, and Norelloidea. The new genus Antulanella has a fine fibrous microstructure of the secondary layer, which is consistent with its allocation in the Hemithiridoidea. Antulanella pancici occurs in association with other brachiopods showing strong Peritethyan affinity and close resemblance to the Jura fauna (= Subtethyan fauna).

Ograniczanie wyników

1 Acta Palaeontologica Polonica

1 Animal Science Papers and Reports

1 Faruga A.

1 Horbanczuk J. O.

1 Michalak K.

1 Motchurova-Dekova N.

1 Mroz E.

1 Orlowska A.

1 Radulovic B.

1 Radulovic V.

1 2008

1 2007

Wyniki wyszukiwania

Shell microstructure and hatchability of turkey eggs

New Barremian rhynchonellide brachiopod genus from Serbia and the shell microstructure of Tetrarhynchiidae