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1. The purpose of this study was to evaluate how feed intake of organic layers varies according to type of forage vegetation available when hens are fed a normal concentrate for organic layers or a nutrient-restricted diet with whole wheat and oyster shells, assuming that the nutrient-restricted diet would reflect the capacity of the hens to forage. 2. Two 23-d experiments were arranged with chicken runs in a 2 x 2 factorial design with two types of complementary feed (concentrate with 184 g/kg dry matter (DM) crude protein vs whole wheat with 120 g/kg DM crude protein) and two types of forage vegetation (grass/clover vs a mixture of forbs in experiment 1 and grass/clover vs chicory in experiment 2): each experiment was carried out in three replications. 3. Twice during each experiment two hens from each run were slaughtered - two in the evening and two the following morning. Subsequently, the birds' crops were removed. Crop content was separated into 8 fractions. 4. For most feed items crop content was found to be significantly higher in the evening than in the morning. 5. Complementary feed significantly influenced the content of several feed items in the crop. In both experiments wheat-fed hens had a significantly higher amount of soil in the crops and a significantly lower amount of weed seeds compared to the concentrate-fed hens. Plant material and grit stone were significantly more abundant in wheat-fed hens only in experiment 2 and numerically more abundant in experiment 1, whereas the amount of oyster shells was significantly higher in wheat-fed hens in experiment 1 and numerically higher in experiment 2. 6. Type of forage itself only significantly influenced the amount of soil in the crops in experiment 1 and amount of seeds in experiment 2, since more soil was found in hens foraging on the mixed forbs and more seeds were found in the hens foraging on the chicory plots, respectively.

SUMMARY In Denmark organic production of broilers (chickens for meat production) has expanded since 1996, when only a few farmers produced approximately 6,000 broilers. At that time, the broilers were sold directly to customers. At present, the yearly production is 350,000 broilers, and professionals organize the sale. Organic broiler production should comply with the overall goals for organic farming. This new production system differs from the conventional system due to specified standards. The production period is prolonged because broilers need to be at least 81 d old when slaughtered, and these chickens are genetically programmed to be slower growing with a maximum growth rate of 30 g/d. Additionally, daily access to roughage, organic feed without coccidiostats, and outdoor pasture areas is required. In the present paper the organic production system and data concerning growth, feeding, animal health, and slaughter quality is described based on an investigation conducted on 9 Danish farms in 1998. This investigation is the first of organic broiler production in Denmark.

Ascaridiosis is still a cause of economic losses in modern poultry production systems. Improving genetic resistance to this disease provides an attractive alternative for free-range organic poultry producers and will eventually reduce the extensive use of anthelmintic drugs. An experiment was conducted to compare resistance to Ascaridia galli infections in Lohman Brown (LB) and Danish Landrace (DL) chickens. A self-cure mechanism to A. galli infections was observed in both breeds. However, significantly higher worm burdens and egg excretion were seen in the DL compared to LB chickens during primary infection. This indicates that breeding for resistance to A. galli is possible in chickens.

The effect of nematode infections on the performance of sheep grazing at different stocking rates was investigated. Six groups of four ewes per group, each having twin lambs, grazed six paddocks at 9, 13 and 17 ewes/ha for two seasons. Three infected groups grazed paddocks contaminated with nematodes, while three control groups grazed parasite-free paddocks. Paddocks received 0, 80 or 160 kg N fertilizer ha−1 year−1 to compensate for increasing stocking rate. Ewes were withdrawn at the end of July. The serum albumin levels were markedly depressed in infected ewes and lambs (p