s of papers 97 eggshell breaking strength, and eggshell percentage were no affected by treatments(P>0.05). Only eggshell thickness was affected by treatments (P<0.05), and RL showed the highest value( 0.1862 mm), followed by BL (0.1785mm).

Interspecific brood parasitism represents a prime example of the coevolutionary arms race where each party has evolved strategies in response to the other. Here, we investigated whether common cuckoos (Cuculus canorus) actively select nests within a host population to match the egg appearance of a particular host clutch. To achieve this goal, we quantified the degree of egg matching using the a...

Due to its central position in the production chain, in-ovo development is influenced by pre-incubation factors that affect the quality of embryonated eggs and incubation conditions themselves, and both may influence egg hatchability and chick quality, as well as bird survival, growth performance, and phenotype in the field. The evolution of the incubation process over the years is characterize...

PHILLIP CASSEY,* JOHN G. EWEN, N. JUSTIN MARSHALL, MISHA VOROBYEV, TIM M. BLACKBURN & MARK E. HAUBER Centre for Ornithology, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK Institute of Zoology, Regents Park, London NW1 4RY, UK Vision, Touch and Hearing Research Centre, University of Queensland, Brisbane QLD 4072, Australia Optometry and Vision Science, Univer...

A total of 1,152 Lohmann Brown laying hens were used to study the influence of level (3.5 and 4.0%) and source (coded FIN, COA, and OYS) of Ca in the diet on productive performance and egg quality from 58 to 73 wk of age. The FIN diet contained all the Ca carbonate as fine limestone (LIM). In the COA and OYS diets, 40% of the fine LIM was substituted with either coarse LIM or oyster shell. Each...

OBJECTIVE An experiment was conducted to determine the effect of superdosing phytase on productive performance and egg quality in laying hens. METHODS A total of 200 42-wk-old Hy-Line Brown laying hens were allotted into 1 of 5 dietary treatments with 5 replicates consisting of 8 hens per replicate. The positive control (PC) and negative control diets (NC) were prepared based on the recommend...

We analyzed the prevalence of thermotolerant Campylobacter spp. compared that of to Salmonella spp. in raw yolk and on eggshells. A total of 2,710 eggs were investigated for each bacterium. Viable bacteria were found in 4.1% (Campylobacter spp.) and 1.1% (Salmonella spp.) of the eggshell samples, whereas the egg yolk samples were negative for both bacteria.

topical application with 100, 200 and 300 ng/ml phytohormone salicyclic acid on commercial traits was analysed in bivoltine csr2, csr4 and csr2xcsr4 crossbreed races of the silkworm, bombyx mori l. the results showed that there was significant increase in larval weight female cocoon weight, male cocoon shell weight, and hatching percentage with 100 and 200 ng/ml, silkgland weight, female cocoon...

The non-avian saurischians that have associated eggshells and embryos are represented only by the sauropodomorph Massospondylus and Coelurosauria (derived theropods), thus missing the basal theropod representatives. We report a dinosaur clutch containing several crushed eggs and embryonic material ascribed to the megalosaurid theropod Torvosaurus. It represents the first associated eggshells an...

A theoretical and experimental study of the fragmentation of closed thin shells made of a disordered brittle material is presented. Experiments were performed on eggshells under two different loading conditions: fragmentation due to an impact with a hard wall and explosion by a combustion mixture giving rise to power law fragment size distributions. For the theoretical investigations a three-di...