This section is from the book "Commercial Gardening Vol1", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
This name is applied to solid and liquid excreta from animals, together with the litter that has been used for bedding down. Wheat straw is generally used for litter, but peatmoss litter has of late years become a rival for bedding in stables. Other materials, such as bracken, shavings, spoiled hay, etc, are used also; but whatever material is used it becomes farmyard manure when it becomes too wet with urine and too foul with droppings to be used any longer for bedding. It is then taken outside and stacked in heaps. The urine of animals being usually richer in nitrates, phosphates, and potash than the droppings, every care should be taken to preserve it, not only for its intrinsic value as a fertilizer, but because it is useful for keeping the litter in such a state of dampness that it will not burn or turn mouldy. Wheat straw will absorb about three times its own weight of liquid, and peat-moss litter about eight times its own weight. It has been estimated that a horse affords 1000 lb. of urine annually containing 89 lb. of solid matter, and a cow 13,000 lb. of urine containing 1023 lb. of solid matter. About 67 lb. of solid matter is contained in 1000 lb. of human urine; 21 lb. in 1000 lb. of pig urine, and 30 lb. of solid matter in 1000 lb. of sheep urine.
The quantity and quality of the excreta vary according to the kind of animal, its age, and the food it eats. The droppings from cows and pigs contain more liquid than those from horses and sheep. Hence the "sloppy" manure from pigs and cows is termed cold, and is useful for "hot" gravelly or sandy soils. Horse and sheep manure, however, is known as hot, and is better applied to heavy or tenacious soils.
It has been estimated by a German scientist that a horse will excrete 28 lb., a cow 73 lb., a sheep 3.8 lb., and a pig 83 lb. per day, and that these excreta mixed with straw litter will yield 33 lb., 81 lb., 4.4 lb., and 12.3 lb. of manure per day from each animal respectively. This estimate is presumably for fully grown animals in a normal state of health.