Hendrix Genetics

The results of 15 experiments realized from 1990 have been used to define more precisely the requirement in Methionine and Sulfur Amino Acids. Results show that the daily requirement for Methionine is related to the bird productivity. If the requirement is expressed in mg per gram of egg mass produced, the requirement appeared independent of the daily egg mass produced. From this analysis, we conc ...

A weekly control of the growth is a must to check the real evolution of the flock: the earlier you know the earlier you can correct.Targets in rearing:To produce a uniform flock and a weight, which is compatible with the intended age at sexual maturity To obtain the correct bodyweight at 4 weeks to secure frame development To achieve steady growth between 4 and 16 weeks with a good development of ...

Chickens are sensitive to changes in the duration of illumination, and these will influence the age of sexual maturity. In addition, feed consumption is greatly influenced by the duration of day length. Lighting programmes have, therefore, different objectives.During rearing, they allow us to encourage growth and to control the birds' sexual maturity. For this reason, we consider it to be essentia ...

After a good starting, the objective of the 4-16 weeks period is to prepare the birds for egg production with an ideal development of:- the frame- the bodyweight- the uniformity- the digestive tract developmentThese objectives could be achieved thanks to:- a correct stocking density and housing conditions- a lighting programme adapted to rearing conditions- a good standard of beak tipping- a good ...

In tropical and subtropical countries, the layers are subjected to important heat stress. This heat stress can occur during long periods. The lower feed intake noticed during these periods is the result of the bird’s reduced ability to lose heat. Pullets and laying hens should maintain their body temperature constant by adjusting their food intake according to their ability to lose heat.The lower ...

The transfer from the rearing farm to the laying facilities is a major stress, accompanied by changes in environment (temperature, humidity…) and equipment. It should be carried out as fast as possible, ideally being completed within a day.Then, between transfer and the peak of production, a rapid increase in feed intake is necessary since the bird has to cover:- its growth till adult bodyweight- ...

In the production as well as the rearing periods, the lighting programme greatly influences the feed consumption. In addition, during all its life, a chicken remains sensitive to changes in the duration of illumination.The objective of the lighting programmes during production period is:- to encourage growth at start of lay- to counteract the harmful effects of decreases in natural day length- to ...

Genetic progress and nutritional consequencesJust as for the other species, genetic progress has a considerable influence on dietary amino acid concentrations. Over the last 30 years, production to a constant age has increased by more than 40 %, while feed consumption has been reduced by about 10 %. An important consequence of this genetic progress has been a change in the daily amino acid require ...

The period from one day old to the point of first egg production is a critical time in the life of the laying hen. It is during this time that the physiological capability of the hen is developed.Success in the rearing period leads to the success in the laying house and start from chick arrival. All the standards and programs set forth in this section have been proven to give excellent performance ...