848 Journal of the Department of Agriculture. 



PRICKLY PEAR AS A STOCK FOOD. 



By Chas. F. Jtritz, M.A., D.Sc, F.I.C., Agricultural Eesearcli 

 Chemist, Capetown. 



The prickly pear, like all piajits which contain much water, is of 

 great service to drought-stricken stock in arid countries, but it follows 

 of necessity that because it contains so much water it cannot at the 

 same time contain much solid nourishment- Those green stem-joints, 

 which are also called sections or cladodes, but which we generally — 

 but wrongly in the case of the prickly pear — call " leaves," often 

 contain as much as 90 per cent, of water, and, accordingly, form too 

 one-sided a diet for stock unless more "solid" food is given at the 

 same time, in order to keep up the balance. Animals may be kept 

 aliA-e for some time on prickly pear alone, but they lose in condition. 



The value of prickly pear lies in its capability of being used as 

 a roughage in. normal times, and as a supplementary food for eking 

 out a scanty supply of other food-stuffs under drought conditions. 



Mr. Ingle, when Chief Chemist of the Transvaal in 1908, pointed 

 out how refreshing and welcome a winter stock-food the prickly pear 

 would prove in the Transvaal, and he recommended burning olf the 

 prickles from the leaves (as for convenience sake I shall continue in 

 this paper to call the stem-joints) by means of a blow-lamp, and then 

 slicing the leaves in a turnip cutter. 



Many analyses of the leaves of various kinds of prickly pear have 

 been published, showing* that the amount of water which they contain 

 when fresh is about 90 per cent. Of the remaining 10 per cent., 

 which constitutes the dry matter, mineral substances like salt and 

 phosphates make up nearly 2 per cent., about 3 to 4 parts per thousand 

 consist of albuminoid or nitrogenous matter, and one part in a 

 thoiisand is oil or fat. The fibrous material in the fresh prickly pear 

 leaf does not make up much more than one per cent. The quantity 

 of sugar in the leaf is g'enerally under one per cent., and about 2 to 3 

 per cent, is made up of mucilage or gum-like substances. 



If the prickly pear leaves are chopped up and allowed to dry out 

 they become relatively more nutritious. The amount of moisture 

 contained in them may drop to about 10 per cent. Of this dried leaf 

 14 or 15 per cent, may be mineral substances, 3 per cent, albuminoids, 

 or proteins, as they are now more generally called; oil or fat would 

 be nearly one per cent. ; fibre about 10 per cent., sug.ir 5 or 6 per 

 cent; and mucilage approximately 18 per cent. 



As regards the fresh fruit of the prickly pear, it is estimated that 

 the husk constitutes 37 per cent, and the seeds 4 per cent. The 

 husk contains about two-thirds of its weight of water, and the shelled 

 fruit slightly less. The whole fruit contains between 6 and 7 per cent, 

 of proteins and about 11 to 12 per cent, of sugar. 



In the New Mexico Experiment Station, some 14 or 15 years 

 ago, the possibility of using a certain variety of prickly pear, Opuntia 

 lindheivieri, in making up a stock ration was investigated. The 



