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991.
An experiment was carried out in which grass was cut and fed indoors, with or without supplementary barley. Seven animals were allocated to each of the following treatments: (1) grass ad lib . without supplementary barley; (2) grass ad lib . with supplementary barley at the rate of 0.5 lb/100 lb bodyweight; (3) grass ad lib . with supplementary barley at the rate of 1 lb/100 lb bodyweight. Supplementary barley increased total dry-matter intake and improved daily liveweight gain and food conversion rate. The mean daily liveweight gains for the 17-week experimental period were 1.60, 1.91 and 2.20 lb and the corresponding feed dry-matter conversion ratios were 6.18, 5.67 and 5.55 for Treatments 1, 2 and 3, respectively.
The dry-matter digestibility of the diets was slightly higher when the grass was supplemented with barley than when grass alone was given. Although barley depressed the digestibility of protein, the absolute and the proportionate retention of nitrogen was increased. This was particularly marked on Treatment 3, presumably because of the higher net energy value of the diet containing the greater amount of barley. The N-retention data corresponded to the rates of liveweight gain obtained.  相似文献   
992.
T. D. Johnston 《Euphytica》1967,16(3):365-369
The construction and use of a variable force penetrometer for measuring the woodiness of kale stems is described.The force required to cause penetration of the probe through the xylem tissue was found to bear a close relationship to estimates of quality based on in vitro digestibility determinations, crude fibre content and visual assessment of lignification in stained transverse sections of stems.  相似文献   
993.
Digestibility data are presented on the following; Andropogon gayanus hay and bush foggage, Arachis hypogoea (groundnut) haulms, Glycine max (soya-bean) hay. Sorghum vulgare (sorghum) leaves and hay, Stizolobium sp. (velvet bean) hay, Vigna sinensis (cowpea) hay and haulms, and S. vnlgare/Stizolobium sp. mixture. The results are discussed from the agronomic aspect.  相似文献   
994.
Forecasting timber production many years in advance has becomea problem of considerable importance in this country becauseof the need to co-ordinate the rapid increase in productionwith the establishment of new timber-using industries. Thispaper describes a change in emphasis in state forest WorkingPlan Inventory methods employed in the predominantly young,coniferous forests of Great Britain and is a development ofthe methods described in a previous paper (‘Problems ofYield Control and Inventory in British Forestry’—D.R. Johnston, 1960, Forestry, 33, 19–36). Total enumerationof the growing stock is no longer the main objective of forestinventory and the new approach is directed towards (a) assessmentof the productive potential of each subcompartment and (b) theintensive enumeration of sample or ‘index’ subcompartmentsinitially and at each re-enumeration as a check on growth predictionsand yield control.  相似文献   
995.
In Saskatchewan, intermediate wheatgrass ( Agropyron intermedium Host. Beauv.) suffered severe winter injury during the 1961–2 winter season, which followed a series of drought years, the most severe being 1961. In two tests, designed to study fertilizer effects, the extent of severe winter injury increased with the rate of application. The killing ranged from 4% where no fertilizer was applied to 90% where 66 lb of N per acre were applied. Slightly more winter-killing occurred after applications of ammonium phosphate/sulphate (16-20-0) fertilizer than after ammonium nitrate (33·5-0-0).
The grass growing in rows 36 in. apart killed out to a greater extent than that growing in rows 18 in apart Less winter injury occurred after spring applications of fertilizer than after application in the fall.  相似文献   
996.
The oral introduction of 0·5 g histamine as the diphosphate into the rumen of sheep produced no effect on the physiological condition of the animals. The feeding of histamine, as the dihydrochloride, in levels up to 1 g/day to sheep on silage diets did not affect the dry-matter intake.  相似文献   
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