Phosphorus forms in animal manure

• Published in: Bioresource technology 1994, Vol.49 (2), p.139-147
• Main Author: Barnett, G.M.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; feces; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; P form; Phosphorus; Soil-plant relationships. Soil fertility. Fertilization. Amendments
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/0960-8524(94)90077-9

The proportion of inorganic (P i) and organic (P o) P in animal feces is affected by rearing conditions. This study was conducted to evaluate the P status of farm animal wastes and the effects of some management factors. Total (P t), P i, residual (P r), acid-soluble organic (P aso), and lipid (P l) P were determined in freeze-dried, ground (2 mm screen) samples of fresh, uncontaminated dairy ( Bos taurus L.), beef ( Bos taurus L.), hog ( Sus scrofa domestica L.), and poultry ( Gallus gallus domesticus L.) feces from commercial farms collected during the winter. Additionally, feces from calves ( Bos taurus L.) fed cut-1 and cut-2 of three cultivars of reed canarygrass ( Phalaris arundinacea L.) and one cultivar of timothy ( Phleum pratense L.) were analysed. Total P varied from 6·7 g kg −1 for feeder cattle feces to 29·1 g kg −1 for hog feces on a dry-matter basis. Of P t, P i ranged from 34·8 (broilers) to 63·2% (dairy), P r from 11·0 (broiler) to 40·8% (finisher beef), P aso from 7·8 (dairy) to 53·4% (broilers), and P l from 0·4 (hog) to 2·1% (feeders). Dry matter ranged from 14·3 (dairy) to 67·5% (broilers). Ruminant feces varied more in P t, P aso, and P l but less in P i and P r than non-ruminant fecal material. Total P and P i were closely related. Fecal P i and P l were higher in cut-2 hay than in cut-1. Calves fed timothy forage produced feces with less P i than those fed reed canarygrass. Some calves on cut-2 forage produced feces with lower P i and less P r on cut-1 material than other animals. Published values were found to be unreliable indicators of fecal P status.