title: Uterine fluid proteins and egg quality characteristics for 2 commercial and 2 heritage laying hen lines in response to manipulation of dietary calcium and vitamin D3.
abstract: The aim of this study was to evaluate the quality of eggs from 2 selected commercial strains of laying hens and 2 unselected lines of chickens fed diets with different combinations of Ca and vitamin D and relate it to the profile of uterine proteins and ultrastructure of the shell. A group of 4 chickens was housed in each of 24 cages. The group consisted of one representative from each of the following breeds: Lohmann LSL- Lite, Lohmann Classic-Brown, Fayoumi, and Light Sussex. Six dietary combinations of Ca and vitamin D(3) (3.35%, 2,500 IU; 4.10%, 2,500 IU (control); 4.85%, 2,500 IU; 3.35%, 200 IU; 4.10%, 200 IU; and 4.85%, 200 IU) were randomly assigned to 4 replicate cages for 2 treatment periods (26-29 and 56-59 wk of age). Data were analyzed as a split-plot design with cage as the main plot and hen as the subplot. Egg quality traits were different (P < 0.0001) between commercial and heritage breeds. Lohmann Brown had stronger shells with higher specific gravity compared with other breeds. Both commercial and heritage birds responded to a drop in vitamin D3 level by marked reduction in shell thickness. The SDS-PAGE profiles of uterine fluid samples revealed a decrease (P < 0.05) in 200-, 150-, 116-, and ≤6.5-kDa proteins, whereas proteins with molecular weight (MW) of 80, 55, 52, 45, 42, and 28 kDa increased with bird age. A 36- and 52-kDa protein band was most intense for Fayoumi compared with other breeds. Ultrastructural characteristics showed flattened and deeply etched mammillary caps for Lohmann Brown and the presence of type A and type B bodies between mammillary cones in eggshells from Fayoumi and Lohmann Lite. The negative correlation between ultrastructural characteristics, which decrease with bird age, and the 116-kDa uterine protein band could provide insight into reduced eggshell quality as hens age.
authors: Department of Plant and Animal Science, Dalhousie University, Truro, NS, B2N 5E3 Canada.
authors: Ravinder
authors: R
authors: Kaur
authors: Bruce M
authors: BM
authors: Rathgeber
authors: Kristen L
authors: KL
authors: Thompson
authors: Janice
authors: J
authors: Macisaac
mesh_terms: D000818:Animals; D030161:Avian Proteins / Q000378:metabolism*; D002136:Calcium, Dietary / Q000378:metabolism*; D002645:Chickens / Q000235:genetics / Q000502:physiology*; D002762:Cholecalciferol / Q000378:metabolism*; D004032:Diet / Q000662:veterinary; D004528:Egg Shell / Q000254:growth & development / Q000648:ultrastructure*; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005260:Female; D008855:Microscopy, Electron, Scanning / Q000662:veterinary; D010063:Ovum / Q000254:growth & development / Q000502:physiology*; D014599:Uterus / Q000378:metabolism
chemical_list: D030161:Avian Proteins; D002136:Calcium, Dietary; D002762:Cholecalciferol