Raw ash
The proportion of inorganic components in animal feed is called raw ash . Raw ash is part of the mandatory declaration on feed packaging.
determination
The raw ash corresponds to the proportion that remains when the feed (consisting of proteins , fats , carbohydrates , organic and inorganic compounds) is incinerated at 550 ° Celsius for six hours . In high-quality animal feed, the raw ash content corresponds to the mineral content (e.g. calcium, phosphorus, iron, copper, zinc, manganese, iodine, selenium, cobalt or sodium) plus the natural raw ash content of the individual ingredients. Inferior animal feed can be contaminated by sand or soil. In order to check whether sand, earth or other inorganic impurities are present, hydrochloric acid is added to the crude ash after incineration, which leaves the pure ash. Soiling by soil with a high proportion of humus cannot be determined using this method, as the humus also burns in the incineration process. Organic mineral feed has a high raw ash content; according to feed law, these may only be designated as such if they contain at least 40% raw ash.
meaning
compatibility
The ratio of protein to crude ash content can be used as an indicator of the digestibility of a feed. The digestibility decreases with increasing raw ash content. The ratio also serves as an indication of how much protein the feed provides. The protein requirement varies in different species, for example cats need a higher proportion of protein in their feed because they consume more protein than dogs, for example.
Ensiling
With increasing Rohasch content which decreases ensilability of feed. The lowering of the pH value is hindered by the high buffer capacity and more lactic acid has to be produced by fermentation to lower the pH. If the proportion of raw ash is too high, incorrect fermentation, for example butyric acid fermentation by clostridia , can occur.
Comparison of raw ash proportions
- Dry food for dogs and cats: 5–8% crude ash
- Mineral feed: min. 40% crude ash
- Horse feed: 5–20% crude ash
- Rabbit food: 5-10% crude ash
- Guinea pig feed: 5–10% crude ash
- Rat / mouse chow: 2-6% crude ash
- Degu / chinchilla food: 5–10% crude ash
- Hamster food: 5% crude ash
- Fish feed: 1–10% crude ash
- Birdseed: 5–10% crude ash
Natural products
- Unpeeled rice: 5% crude ash
- Polished rice: 0.5% crude ash
- Corn: 8-11% crude ash
literature
- Jürgen Weiß: Animal production . Georg Thieme Verlag, 2005, ISBN 3-8304-4140-1 .
- Clinical Dietetics for Small Animals, Volume 1 . Michael S. Hand Verlag, 2002, ISBN 3-87706-893-6 .
- The Agricultural Experimental Stations, Volumes 19-20 . G. Shönfeld (CA Werner), 1876.
- Helmut Meyer, Jürgen Zentek: Nutrition of the dog: Basics - feeding - dietetics . Georg Thieme Verlag, 2005, ISBN 3-8304-4151-7 .
- Theodor Reuning, Friedrich Nobbe: The agricultural test stations, volumes 18-19 . Oscar Johann Kellner Verlag G. Shönfeld (CA Werner), 1875.
Individual evidence
- ↑ a b Guide to the labeling of feed materials and compound feed. Federal Office for Consumer Protection and Food Safety , April 24, 2012, accessed on August 21, 2018 .
- ↑ a b c Reinhard Resch: Effects of earthy feed contamination. In: Farmer. 2014, accessed August 21, 2018 .
- ↑ Michael S. Hand, Craig D. Thatcher, Rebecca L. Remillard, Philip Roudebush: Clinical Dietetics for Small Animals , Volume 1 . 4th edition. Michael S. Hand Verlag, 2002, ISBN 978-3-87706-893-9 , pp. 175 .