A crossbreeding experiment was carried out between two Egyptian strains of chickens namely Mandarah (MM) and ElSalam (SS). The two purebred strains and their reciprocal crosses (MS and SM) were used to estimate the effect of crossing on egg laying and egg quality parameters, direct additive and maternal additive effects as well as heterosis and direct heterosis percentages for studied traits. R...

The aim of this study was to evaluate the effects of 28 single nucleotide polymorphisms (SNP) in 10 candidate genes previously shown to be associated with quality traits in pigs and cattle. The data set comprised 28 traits recorded on a commercial population of 536 Aberdeen Angus-cross beef cattle. Among the traits, 20 were carcass and sirloin quality related, one mechanical measure of tenderne...

There were no considerable up to date on the trace element requirements of commercial poultry in recent years in despite of the progress in their performance traits. One of the more prevalent problems in modern broiler production system which could be attributed to the trace mineral inadequacy is skeletal disorders. Zinc, is an essential trace element which acts as a co-factor in several metalo...

Five Iranian native silkworm groups: Baghdad, Khorasan Orange, Guilan Orange, Khorasan Pink, Khorasan Lemon, and 107 and 110 commercial lines (12 families from each breed) were randomly selected and reared during 2003-2005 (five generations in spring and autumn). In each family, 30 male and 30 female cocoons were individually recorded for weight, shell weight and shell ratio. From among the nat...

Previously identified QTL regions on BTA1 and BTA5 were investigated to validate the QTL regions and to identify candidate genes for growth and carcass traits in commercial cattle populations from the USA and Korea. Initially, a total of 8 polymorphic microsatellite (MS) markers in the BTA1 and 5 QTL regions were used for Chi-square tests to compare the frequencies of individual alleles between...

For several plant and animal species, Darimont et al. (1) present compelling evidence that rates of phenotypic change driven by human harvest far outpace those driven by other selective forces. From a life-history perspective, commercial and trophy harvesting also resulted in smaller size/earlier age at first reproduction, smaller adult body size (sometimes associated with shorter lifespan), an...

Maize is an important food and feed crop in many countries. It is also one of the most important target crops for the application of biotechnology. Currently, there are more biotech traits available on the market in maize than in any other crop. Generation of transgenic events is a crucial step in the development of biotech traits. For commercial applications, a high throughput transformation s...

This paper discussed how to optimize production traits for two layer breeds in Egypt. The first breed is indigenous Fayoumi and the second exotic Leghorn. Both breeds have their different performances and each breed was preferred over the other for some particular traits. By crossing the two breeds, the crossbreds could benefit from the strengths of the purebreds for particular traits. The econ...