Encapsulation is a common strategy among marine invertebrate species. It has been shown that oxygen and food availability independently constrain embryo development during intracapsular development. However, it is unclear how embryos of species with different feeding strategies perceive these two constraints when operating jointly. In the present study, we examined the relative importance of di...

This study was conducted to determine the effect of hen production cycle (HPC) and the effect of egg weight (EW) at the same egg production level on egg quality, egg composition, hatchability, duckling quality, and first-week BW in Pekin ducks. For HPC, hatching eggs were obtained from different Pekin-duck breeder flocks, aged 31 wk for the first production cycle (HPC1) and 78 wk for the second...

Th is study was designed to investigate whether inclusions of coenzyme Q10, alpha lipoic acid and their combination into diets of hens improve egg quality characteristics. Forty-eight, 33 weeks old Lohmann Brown hens were assigned randomly to four groups of 12 hens each and fed either a basal diet or basal diet supplemented with 2 g/ kg coenzyme Q10, 0.4 g/kg alpha lipoic acid and 2 g/kg coenzy...

The catecholamine dopamine is present in both the central nervous system and in the peripheral tissues of molluscs, where it is involved in regulating reproduction. Application of exogenous dopamine to the isolated albumen gland of the freshwater pulmonate snail Helisoma duryi (Wetherby) induces the secretion (release) of perivitelline fluid. The major protein component of the perivitelline flu...

this experiment was conducted to evaluate the effects of vitamin c on laying hens performance, egg characteristics and some blood parameters under normal rearing condition. one hundred and ninety two 24 - weeks - old laying hens diet were used in a completely randomized design with 4 treatments (0, 250, 500 and 750 mg vitamin c/kg diet) and 4 replicates for 105 days. although feed consumption, ...

OBJECTIVE A study was conducted to test six threonine (Thr) levels (0.39%, 0.44%, 0.49%, 0.54%, 0.59%, and 0.64%) to estimate the optimal dietary Thr requirements for Longyan laying ducks from 17 to 45 wk of age. METHODS Nine hundred Longyan ducks aged 17 wk were assigned randomly to the six dietary treatments, where each treatment comprised six replicate pens with 25 ducks per pen. RESULTS...

A quantitative analysis of NMR proton relaxation in hen egg albumen and yolk is undertaken to research the causes of quality loss during the first few days of storage and to access the feasibility of an on-line NMR sensor of internal egg quality. It is shown that the change in the transverse relaxation in thick egg albumen mainly results from an increase in proton exchange rate resulting from a...

Salmonella spp. present in pasteurized egg albumen are often difficult to recover by direct plating because of thermal injury and the presence of innate iron binding and other antimicrobials in egg white. The literature has reported a multiplicity of selective and nonselective media used to recover heat-injured Salmonella, to measure the proportion of injured cells, or both. This study compared...