Showing 3 of 3 results for "phosphorus"
Two experiments were conducted to determine the available phosphorus (AP) requirement of laying hens and to examine the effect of different dietary AP and calcium (Ca) concentrations on egg production and egg shell quality from the start of lay to 80 weeks of age. The influence of dietary phytase supplementation was also examined. The established adequate Ca and phosphorus (P) levels for layers have been challenged due to the continuous advances in genetic improvement, nutrition, environment, and management.
A high level of egg production was maintained in both experiments and it appears that all the dietary AP concentrations met the P requirement of hens even at the lowest level of 1.5 g/kg diet (for hens fed wheat and sorghum based diets). The results obtained from the present study are in agreement with overseas reports, which suggest that modern laying hen strains have much lower AP requirements than earlier strains.
Poultry layer manure and litter composition data are essential for accurately determining sustainable application rates of manure to crops and pastures. This study collected some 20 samples of manure and litter from five different layer production systems from all major production regions in Australia. Compared to data previously reported for Australian layer manure and litter, there are several trends that can be observed which are likely to be the result of new management systems (belt manure removal) which produce manure with significantly shorter in-shed residence times compared to high rise sheds.
Economic constraints and public concerns have compelled the poultry industry to increasingly use a range of cheaper, alternative plant-derived feedstuffs in feed formulations and eliminate the use of animal by-product meals. However, use of such ingredients also increases the dietary levels of phytic acid which can have wide ranging ramifications on performance of egg production, quality and nutrient digestibility. This publication details several studies which examined the effectiveness of supplemental phytase in improving the availability of phosphorus, amino acids and energy from plant feed ingredients for laying hens.
Search for projects, events, activities, issues, popular topics, publications, authors, keywords within R&D