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Textiles and fibre
The fibre content in nettle shows a high variability and reaches from below 1 % to 17 %. Under middle-European conditions, stems yield typically between 45 and 55 dt / ha, which is comparable to flax stem yield. Due to the variable fibre content, the fibre yields vary between 0.2 and 7 dt / ha, but the yields are normally in the range between 2 and 4 dt / ha.

Fibre varieties are normally cloning varieties and therefore planted from vegetative propagated plantlets. Direct seeding is possible, but leads to great heterogeneity in maturity.

Nutrient contents
Fresh leaves contain approximately 82.4% water, 17.6 % dry matter, 5.5 % protein, 0.7 to 3.3 % fat, and 7.1% carbohydrates. Despite the low fat content, especially mature leaves contain an interesting omega-3 (n-3): omega-6 (n-6) ratio, because about 40% of the fatty acids are α- Linolenic acid, a valuable omega-3 acid. For exact fatty acid contents see Table 1. Seeds contain much more fatty acids than leaves.

Minerals (Ca, K, Mg, P, Si, S, Cl) and trace elements (Mn, Cu, Fe) contents depend mostly on the soil and the season.

Nettle contains different secondary metabolites. Carotenoids can be found primarily in the leaves, where different forms of lutein, xanthophyll and carotene are present (Table 2). Some carotenes are precursors of vitamin A (retinol), their retinol equivalents RE or retinol activity equivalents per g dry weight are 1.33 for mature leaves and 0.9 for yound leaves. Nettle contains much less than carotenes and retinol than carrots, which contain 8.35 RE per g fresh weight. Depending on the batch and the leave and stem content, nettle contains only traces of zeaxanthin or between 20 – 60 mg / kg of dry matter. Nettle contains ascorbic acid (vitamin C), riboflavin (vitamin B2), pantothenic acid, vitamin K1 and tocopherols (vitamin E). The highest vitamin contents can be found in the leaves.

Poultry: Egg yolk colouring in laying hens
At first, whole shoot stinging nettle was fed experimentally to broiler chicken for its antioxidative properties. The broiler chicken fed 25 g stinging nettle per kg feed did not have improved antioxidative meat properties, but had a yellow skin colour. Because of this findings, which indicated a good colouring property, nettle was used in laying hens instead. Another study that fed nettle powder (10 g / kg feed) or nettle essential oil to broilers did not find an improvement of the broilers' performance.

In laying hens, nettle can effectively be used as an egg yolk colorant instead of artificial pigments or other natural pigments (derived from marigold for yellow). Nettle has high carotenoid contents, especially lutein, β-carotene and zeaxanthin, of which lutein and zeaxanthin act as yellow pigments. Feeding as little as 6.25 g dry nettle per kg feed is as effective as the synthetic pigments to colour the egg yolk. Feeding nettle has no detrimental effect on the performance of the laying hens or the general egg quality. The nettle dosage can be increased to 25 g per kg feed without impairing the performance. Oxidation properties of the egg yolk lipids were not affected by the nettle addition, as the natural antioxidants (tocopherols and others) from nettle did not appear to be transferred to the egg. Because the carotenoid content varies, which is assumed to depend on climate, plant age and genotype, analyses of the carotenoid contents are recommended prior to large-scale application.

Ruminants
Nettle sting not only humans, animals do not like to touch fresh stinging nettle. If the nettle are wilted or dry, voluntary intake can be high. Dry nettle shoots are said to be “as good as good alfalfa hay”. As with other leafy herbs with relatively hard stems, the harvest should be done carefully to avoid leave drop losses. Nettle can be conserved as hay or silage.