Plant Sanitation. 



513 



[June, 1910. 



much remains to be clone, it also, as It is indeed a graceful act of repara- 

 tive have said, indicates how remark- tion that the country which has sup- 

 able has been the progress in some plied us with so many mischievous 

 directions in the unravelling of com- pests should now come to our aid so 

 plex life histories of parasitic fungi, successfully in the work of mitigating 

 such, for instance, as the rusts. the evils for which they are responsible. 



LIVE STOCK. 



THE DIGESTIBILITY OP PRICKLY 

 PEAR WHEN FED TO CATTLE. 



(Agricultural News, VII. 168, 

 October, 1908.) 

 A pamphlet has lately been issued by 

 the United States Department of Agri- 

 culture (Bulletin 106 of the Bureau of 

 Animal Industry) containing a detailed 

 report on a lengthy series of experiments 

 conducted at the College of Agriculture, 

 New Mexico, in order to test the diges- 

 tibility of the cacti known as ' prickly 

 pear' (Opuntia spp,) when fed, both alone 

 and in conjunction with other foods, to 

 cattle. 



Previous bulletins issued by the Depart- 

 ment have given analyses showing the 

 chemical composition of a large number 

 of cacti, including prickly pear, but 

 since the value of a material as a food is 

 not determined solely by its composition, 

 it is necessary also to know the percent- 

 age digestibility of the nutrients found 

 present by the chemist. 



The mode in which the digestion ex- 

 periments are conducted is simple. First 

 the animal is fed on the feeding stuff for 

 a few days until all other feeds have 

 been removed from the alimentary canal. 

 The animal is then, under suitable con- 

 ditions, fed with a weighed amount of 

 the feeding stuff, the composition of 

 which is determined by analysis. All 

 the liquid and solid excreta is collected, 

 weighed, and analysed, and the amount 

 of nutrients it is found to contain is sub- 

 tracted from the amount of the corres- 

 ponding nutr ients fed. In this way the 

 percentage of each constituent digested 

 is ascertained. . 



The following were among the conclu- 

 sions arrived at as a result of the experi- 

 ments : — 



The average digestibility of the nutri- 

 tive constituents of prickly pear (Opuntia 

 spp.), fed alone, were : dry matter, from 

 63-96 to 65-86 per cent. ; ash, 33-68 to 35 81 

 per cent. ; albuminoids, 40'87 to 5747 per 

 cent. ; fat, 68'38 to 69-02 per cent. ; carbo- 

 hydrates (starches, sugars, etc.), 78*95 

 to 81-78 per cent, and fibre, 41 -32 to 53 99 

 per cent. 



65 



Compared with ordinary green fodder 

 foods, it may be said that the above 

 figures show a somewhat low digestiblity 

 for the albuminoids of prickly pear, a 

 very low digestibility for the ash, but a 

 very good digestibility for the carbo- 

 hydrates. Taken altogether, the digesti- 

 bility of the various constituents is 

 about the same as that of immature 

 green maize fodder. 



When prickly pear is fed with well- 

 cured fodder, as hay for instance, or 

 oats, cotton-seed meal, etc., the digesti- 

 bility of both materials is increased. In 

 these cases the prickly pear has a greater 

 food value than the above figures would 

 seem to indicate. 



The albuminoid ratio, i.e., the ratio of 

 albuminous, or nitrogenous constituents 

 to carbohydrates, is very low in prickly 

 pear. Hence, much better results will 

 always be obtained when it is fed with 

 some food rich in nitrogenous con- 

 stituents, as pea, or bean, or cotton-seed 

 meal. 



It is suggested that a satisfactory 

 ration for milch cows would consist of 

 50 lb. of chopped prickly pear, 5 lb. of 

 cotton-seed meal, and a small amount of 

 rough cured fodder, as hay or straw. 



BEE-KEEPING IN CEYLON. 



As to the productiveness of the indige- 

 nous bee (memessa) under the best 

 system of culture, the data available are 

 very limited ; but there can be no doubt 

 that the indigenous bee is sufficiently 

 productive to be remunerative. The 

 Italian bee is probably better— it is 

 certainly easier to handle and can be 

 subdued with a single puff of smoke, 

 but beekeeping started with the indige- 

 nous bee can be readily extended to 

 the Italian or any other foreign variety. 

 Thanks to Mr. Shanks, the chief engi- 

 neer of the Harbour Department, who 

 is the Pioneer in this matter, the Italian 

 bee has beeu successfully introduced 

 aud will probably spread to all parts 

 of the Island, As to the quality of the 

 honey and wax produced by the local 

 bee and the imported bee there should 



