摘要:

The survey of literature shows that palatability is a very complex subject which has not attracted the attention it deserves. Grasses and clovers are most readily consumed when they are making rapid growth and so contain a good percentage of carbohydrates, provided that they do not contain too much water and are not lacking in fibre. Palatability may be influenced by species, strains, manuring and management of cutting and grazing. Palatability varies with the kinds of animals, their ages and condition. Since there are so many deficiencies in knowledge of palatability it is recommended that this subject should receive more attention from research workers in plant breeding, chemistry and crop and animal husbandry.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00332.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

In a seed crop of S24 perennial ryegrass the processes of anther exsertion and seed formation were measured in inflorescences which emerged early, intermediate and late. The peaks of anther exsertion in the three groups were simultaneous, although the proportion of heads showing anthers was lower in late heads.Two‐thirds of all florets set seed, but the proportion was lower in late heads than in the earlier groups. There was a slight fall in floret fertility in the upper spikelets, compared with those in the middle and at the base of the spike, and a marked reduction in fertility in the outer florets of each spikelet.Factors likely to affect the efficiency of the pollination and fertilization process are discusse

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00333.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

Field experiments on the management of ryegrass/white‐clover pastures for seed production were carried out from 1958 to 1961. Replicated trials with1/6‐acre plots compared continuous grazing, rotational grazing and cutting once at the silage stage of growth as methods of pasture management from April to June. An additional mechanical method, gang mowing, was introduced in 1960 and Hayter mowing was used in 1961. In 1958 to 1960 the treatments were studied with and without the application of 70 lb nitrogen per acre. Clover flower heads per square foot, clover seed and ryegrass seed yields were greatest under continuous grazing, although in some years comparable results were obtained from the mechanical defoliation treatments. There were substantial differences between potential and harvested clover seed yields, the latter ranging from 20% to 75% of the potential yield. The weight of ryegrass seed harvested was highest under continuous grazing and least under the cutting treatments. The nitrogenous fertilizer increased the production of herbage dry matter and of ryegrass seed, but greatly reduced clover seed yields. The results are discussed in relation to the influence of weather on the incidence of flowering and the influence of methods of defoliation on flower‐bud emergence. It is concluded that mechanical methods of defoliation can produce yields similar to those obtained under continuous grazing, provided that cutting is carried out at the correct stage of g

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00334.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A simple technique for the determinationin vitroof the dry‐ or organic‐matter digestibility of small (0·5 g) samples of dried forages is described. It involves incubation first with rumen liquor and then with acid pepsin. Using 146 samples of grass, clover and lucerne of knownin vivodigestibility (Y), the regression equationY= 0·99X–1·01 (S.E. ± 2·31) has been calculated, whereX=in vitrodry‐matter digestibility. This technique has been used for the study of the digestibilities of plant breeder's material, of the leaf and stem fractions of herbage and of herbage consume

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00335.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00336.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A two‐fold investigation into the value of nitrogen (N) for milk production is described. 1. A technical and economic investigation on commercial farms since 1946. The main findings of this investigation are: (a) grass is the cheapest source of food; (b) food costs amount to ⅔ of total milk production cost and therefore grass has an important role; (c) of the three ways of using extra grass, the commercial farms tended to use increased stocking and to a lesser degree the substitution of grass for purchased feed, rather than relying on achieving higher yields per animal; (d) by 1961 the most intensive farms in this Investigation were applying to their grassland 200 units N per acre, or more, and were achieving profits exceeding £20 per acre. 2. A comparison of two 54‐acre units, one using substantial quantities of N and the other using none, and incorporating the findings of the Commercial Farm Investigation (i.e. using extra grass grown by N to carry more cows); this illustrated clearly the substantial profit advantage for intensive use of N on grassland. These two methods of investigating the value of N for milk production were complementary and it is suggested that their wider application would be of benefit to British f

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00337.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00338.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

The magnesium contents of mixed herbage and four individual grass and clover species were studied under four treatments—control, magnesium sulphate, magnesian limestone and carboniferous limestone.The magnesium values were lowest in the spring and early summer and then increased to maximum values by the autumn. The seasonal variations, however, differed appreciably from year to year.The effect of magnesian limestone on the magnesium content of mixed herbage was relatively small in the year of application, but increased during the following years and reached a maximum in the fourth year after application. The increase in magnesium uptake from the magnesium sulphate treatment was small after the first year, whilst carboniferous limestone slightly depressed the magnesium content. This depression, however, was very small and probably of no practical significance.The magnesium content of red clover was about 50% higher than that of Italian ryegrass, cocksfoot and white clover. In the second year after application magnesian limestone had a much greater effect on the magnesium content of the clovers than on that of the grasse

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00339.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

The effects of breed, rate of stocking and the creep feeding of concentrates to lambs have been studied when using intensive creep‐grazing techniques for the production of lamb fat from the ewe. With the right type of ewe and appropriate management, high rates of stocking, giving high outputs of lamb per acre, need not result in failure to market lambs fat by weanin

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00340.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A comparison of Aberystwyth‐bred and commercial grass varieties on two small farms of approximately 17 acres was started in April 1958. The 10 plots comprising each unit are scattered in pairs over a total area of 35·5 acres [used from 1951 for a grazing management experiment (1, 2)]. The management and results for the first three years are given in this paper.Varieties for both long‐ and short‐term leys were compared; the re‐seeding plan and seeds mixtures used are detailed. The stock numbers, grazing management and fertilizer treatments were kept as nearly similar as possible for the farms and for the individual mixtures. Figures for utilized herbage production from individual plots, assessed from grazing data and from sample cuts taken during silage and hay making, are discussed in relation to botanical composition. The levels of production are given in terms of utilized starch equivalent, live‐weight gain, wool from the ewes and cattle grazing days. All show consistent differences in favour of the Aberystwyth‐bred varieties, but mask a difference in favour of Danish compared with S

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00341.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY