2 PROCEEDIXGS OF THE ROYAL SOCIETY OP QUEENSLAND, 



crops. A leading recommendation of the Commission was 

 that the utiUty as stock feeds of the prickly pears mthin the 

 State should be investigated. 



The principal naturalised opuntia of Queensland is 0. 

 inermis, a variety with few spines, though its abundant fine 

 prickle necessitates preparation before feeding to stock. 0. 

 inermis was employed by the author in the trials with steers, 

 dairy cows, and sheep here detailed. The trials with steers 

 (1916) enabled a conclusion to be arrived at with regard to the 

 wholesomeness and palatabiUty of prickly pear, and were a 

 useful preliminary to the work with dairy cows. The dairy 

 herd experiments (1917) were designed to test the value of 

 prickly pear as a roughage in rations for milk production. The 

 sheep experimentation (1917) constitutes, it is beheved, the 

 first systematic trials of prickly pear with sheep recorded. 



PART I.— PRICKLY PEAR IN THE RATIONS OF 

 STEERS. 



Plan of Experiment. 



The animals employed in the experiments were eighteen 

 mature steers, principally of Shorthorn and Hereford strains. 

 The beasts were stall fed and kept in an enclosure bare of 

 herbage. The prickly iDcar was harvested and passed through 

 a power-driven Texan pear-slicer before feeding, but not 

 otherwise prepared. 



The main trials are described as maintenance trials, but, 

 the rations providing generally nutriment in excess of that 

 necessary to merely preserve body weight, they are such in 

 the economic rather than the strict physiological sense. Two 

 series were conducted, viz. : — One in the winter season when a 

 small amount of hay was provided as roughage in addition to 

 prickly pear ; the second in spring when, after recognition of 

 the restriction by other feeds of the prickly pear consumed, the 

 feeds supplementing prickly pear were limited to concentrates 

 or legume hay for the supply of necessary protein. 



The insufficiency of prickly pear alone for the mainten- 

 ance of beasts was demonstrated in the first trials. 



The recognition of the importance of palatabiUty of a feed 

 in its evaluation led to some study of the appetite displayed 

 by experimental animals for prickly pear. The number of 



