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1.
The production and use of cocksfoot foggage for winter grazing at the Hannah Dairy Research Institute in the period 1956–61 is described. Two acres of cocksfoot (S37) were sown broadcast in 1956 and two acres were drilled in rows 28 in apart in 1957. The average annual application of fertilizer nutrients was 118 lb. N, 51 1b. P2O5 and 142 lb. K2O per acre.
The mean yield of the broadcast section was 7450 lb. dry matter/acre/annum compared with 6090 lb. from the rowcrop section. Normally two crops of grass were harvested from the field in the summer, and one grazing was made in the winter. The yield of winter herbage dry matter was 28% and 26% of the total annual yield of the broadcast and the rowcrop sections, respectively.
The field was grazed for four successive winters by 5–10 bulling heifers each weighing 650–850 lb. They received no other feed during the grazing period. Grazing started in December and finished in February, March or April in different years. The mean intake of herbage dry matter was only 6 lb./day, and on average the heifers lost 80 lb. liveweight each winter. This loss was regained after 4–6 weeks when the winter grazing finished. Twenty-nine of the 30 heifers held to the first or second service while grazing the winter herbage.
On average the broadcast section gave 340 heifer-grazing-days per acre during the winter and the rowcrop section 260 days. The cost of a heifer-grazing-day was 3id. and 4id. on the broadcast and rowcrop sections, respectively.
The dry matter of the herbage cut on 19 December 1960 had a digestible crude protein content of 59% and a starch equivalent of 34.
It is concluded that on well-drained land the technique of foggage production and of winter grazing can usefully extend the normal grazing season and hence reduce the costs of winter feeding.  相似文献   

2.
《Grass and Forage Science》1964,19(4):376-380
An investigation into the merits of intensive rotational grazing or paddock grazing was started in 1960. The experiment covered 40 acres, half of which was divided into 20 single-acre paddocks and the other half into 2 fields of 9 and 11 acres, respectively. Two groups of carefully paired cows were used to measure the output of milk per acre. Surplus grass was used for drystock and for conservation. The final output was expressed in terms of U.S.E. per acre, which was computed from the records of milk production, livestock maintenance and fattening and grass cut for conservation. The following conclusions seem reasonable: (a) Where the stocking rate is the same under both systems and the grass supply exceeds the animals' appetites, very little difference in terms of milk yield per acre will be found between intensive rotational grazing and lax rotational grazing over the grazing season; (b) Where, because of heavier stocking or a poorer growth of grass, the animals' appetites begin to exceed the grass supply, the intensive system of rotational grazing will be able to carry the stock for a longer period and consequently will give a greater output of milk per acre; (c) Intensive rotational grazing gives greater opportunity for taking off surplus grass for dryslock or for conservation.  相似文献   

3.
An experiment was started in 1957 that compared the production from dairy cows on daily strip-folding with that from a system of rotational grazing where the cows were given a fresh allocation of pasture about once or twice a week. Management was so arranged that equal areas of pasture were grazed off by the same number of cows in a similar period of time. The experiment was carried out at two rates of stocking, one about 20% greater than the other, the lower rate considered to be equivalent to good close folding practice and the higher rate therefore somewhat restrictive. No supplementary food was given during the grazing season.
At the high rate of stocking, rotational grazing gave an average milk yield of 40 lb./cow/day whilst daily strip-folding yielded 38 lb./cow/day. At the low rate of stocking production was 42 lb./cow/day for both methods.
At the high rate milk yield/acre from the rotational grazing was 1007 and from the strip-folding 977 gals. At the low rate comparable results were 881 and 874 gals.
There was no general trend in yield per cow or per acre in favour of either the rotational grazing or daily strip-folding systems of management. Increasing cow days/acre by 21% decreased yield/cow/day by 7% but significantly increased milk yield/acre, by 13%.  相似文献   

4.
A new simplified grazing management system has been devized for spring- or antumn-born calves scbednled for beef production at 18 months of age on a grass/cereal system. The new system which can be conveniently described as the two-field system obviates the need for paddock fencing and paddock water installations, is simple to operate and is giving results in terms of liveweight gain performance and stocking rates per acre which are comparable with those from paddock systems. The new system employs the old practice of set-stocking. Two fields are used, however, and these are alternately set-stocked and cut for silage, or vice-versa. It has been found that by using N fertilizer to the same extent as in intensive paddock systems, i.e. around 250–350 units N/ac, it has been possible to achieve similar stocking rates/ac and performance has been unimpaired. No bealth upsets have occurred as a result of applying fertilizers on fields in the presence of grazing cattle over a period of four years at two centres, Jealott's Hill and The Leaths, in trials involving hundreds of beef cattle and dairy cows. This new system of grazing management for beef cattle is now well proven and can now be recommended to farmers as an alternative to paddock grazing.  相似文献   

5.
Plots were sown broadcast with ryegrass, cocksfoot or timothy and were strip-grazed at various times during three successive winters by store cattle maintained almost entirely on foggage. In the first winter the plots were rested from 2 September. Each was sampled when required for grazing and the mean organic-matter yield was 2020 Ib. per acre containing 17.5% crude protein. In the two following years, when rested from 15 July and 10 August, November yields were 4340 Ib. (11.8% crude protein) and 3003 Ib. (16.0% crude protein), respectively. Ryegrass yields were 15–30% higher than timothy and 25–50% higher than cocksfoot. Losses during winter due to rotting were related to botanical characteristics and were 40% for ryegrass, 30% for timothy and 10–20% for cocksfoot. Cocksfoot was the most suitable for winter-grazing since it had the highest stock-carrying capacity at all times. This was due mainly to high consumption of ryegrass and timothy, not affecting live-weights, and increasingly poor utilization of the ryegrass produced. It is emphasized that grazing animals should be used when evaluating pastures. Foggage production is considered as a method of herbage conservation and in relation to whole-year pasture output.  相似文献   

6.
Two comparisons between spring and autumn pasture for beef cattle were made. Animals used in all comparisons were of similar breed and weight and were subjected to the same feeding regime for 6–8 weeks before turn-out. The pastures were grazed on an equal grazing pressure basis between season comparisons. The pastures received similar rates of fertilizer N between seasons and had similar lengths of rest period for regrowth. Intakes of digestible OM were greater per unit of metabolic liveweight in spring than in autumn. Daily liveweight gains in spring were high, being 1·09 and 1·37 kg (2·4 lb and 3·0 lb), but were lower from autumn pasture at 0·98 and 0·71 kg (2·2 lb and 1·6 lb). Weather was implicated as a factor affecting daily gain from autumn pasture. Greater herbage yields in spring supported 42 and 204 more grazing days per ha which together with the greater gains per animal supported 80–120% more liveweight gain/ha.  相似文献   

7.
Successful integration of rotational grazing into livestock production systems requires estimates of pasture growth rates for feed budgeting of daily animal intake. By matching livestock nutrient demand with forage availability, over-feeding of supplements can be minimized, which reduces feed costs and the need lo manage surplus nutrients, A three-year grazing study was carried out on a Kentucky bluegrass ( Poa pratensis L.)-dominant pasture to estimate the daily quantity of herbage available to cattle in an intensive, rotational grazing system. Herbage production, species composition, and forage quality were determined in each of the six grazing cycles in a year, from April until September. The average length of a grazing cycle was 28·6 d, with 2·7 d for duration of grazing on a paddock. Pre-grazing and post-grazing sward heights, measured with a plate meter, were 14 and 7 cm, and the corresponding herbage masses were 1955 and 775 kg DM ha−1 respectively. Under adequate soil moisture during 1989, herbage available for daily intake was 53 kg ha−1 from April until mid- August, declining to approximately 32 kg ha−1 d−1 by the end of September. Distribution of this herbage was fairly uniform until the end of August. However, a dry summer in 1991 reduced herbage availability to 15 kg ha−1 d−1. Bluegrass and white clover ( Trifolium repens L.) formed 70% of the herbage yield during the period April–June. Later in the season, dead matter and other species increased, reducing the contribution of bluegrass and clover to approximately 60% of total dry matter. While these pastures have the potential to provide significant amounts of forage for 5–6 months in a year, additional on-farm forage reserves are needed during periods of water stress.  相似文献   

8.
Two grazing systems, a paddock system and a ‘Wye College’ system, were compared in two 20-week experiments nsing 16 and 20 spring-calved Ayrshire cows in 1970 and 1971, respectively. A sward of S23 perennial ryegrass was used, and an average of 342 kg N/ha (305 lb N/ ac) was applied per annum. The paddock system had 28 separate paddocks; one paddock was grazed each day in rotation and occasionally topped in mid-season. The Wye College system had 4 plots of equal size and the cows were offered 1/7 of one plot each day; no back fence was used and surplus herbage was neither cut nor topped. The stocking rate on hoth systems was 1 cow per 0.20 ha (0.49 ac) in 1970 and per 0.16 ha (0.40 ac) in 1971. The mean daily milk yields per cow on the paddock and the Wye College systems were 16.2 and 15.3 kg (35.7 and 33.7 lb), respectively, in 1970; and 18.1 and 18.4 kg (39.9 and 40.6 lb) in 1971. The average annual output of milk was 13,500 and 13,150 kg/ha (1200 and 1170 gal/ac) on the paddock and Wye College systems, respectively. The fat and solids-not-fat (S.N.F.) contents of the milk were not significantly affected by the grazing system. It is concluded that the Wye College system was as effective as the paddock system in producing a high output of mUk per ha, but at a lower cost and with far fewer management decisions.  相似文献   

9.
The sheep grazing intensity and herbage intake on 3 high-level grasslands above 2250 ft were investigated. The seasonal intake, which varied from 450 to 700 lb dry matter/acre, was obtained by the yield-difference method, using cages moved monthly.  相似文献   

10.
An experiment on the prevention of hypomagnesaemic tetany by foliar application of calcined magnesite was carried out with the dairy herd of Greenmount Agricultural College. Hypomagnesaemia and tetany were prevented by'dusting' pasture with calcined magnesite at the rate of 28 lb per acre just before grazing, whereas hypomagnesaemia and cases of tetany (including one death) occurred when the animals were grazing pasture which had not been dusted.  相似文献   

11.
The effects of three stocking rates on fat-lamb production were examined. These stocking rates were imposed upon four grazing systems. The grazing managements had no significant1 effects upon the rate of liveweight gain or the total liveweight of lamb produced per acre, nor were the ewes' liveweights significantly affected. Reasons are suggested. The lambs' rate of liveweight gain was related negatively and the total liveweight of lamb produced per acre was related positively to stocking rate. The ewes' liveweights were similarly affected, there being the highest losses of liveweight under the high stocking rate. In all cases significant differences existed between the stocking rates and there was a significant linear relationship between them. It is concluded that high stocking rates are essential to obtain the maximum fat-lamb production on a 'per acre' basis.  相似文献   

12.
WILD WHITE CLOVER SEED PRODUCTION   总被引:1,自引:0,他引:1  
Field experiments on the management of ryegrass/white-clover pastures for seed production were carried out from 1958 to 1961. Replicated trials with 1/6-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 growth.  相似文献   

13.
An experiment conducted in south-west Scotland during 1956 and 1957 to investigate an outdoor method of rearing calves on pasture, with and without supplementary food, is described.
Twenty-four Ayrshire bull calves were put on pasture at 2 weeks of age and received an average of 37 gallons of whole milk up to the time they were weaned at 8 weeks old. Twelve of the calves received no supplementary feeding, but the other twelve each ate 257 lb. of a meal containing oats, linseed cake, flaked maize and fish meal from their 3rd to their 20th week.
The calves were moved around a series of plots (0.4 acre) which yielded an average of 1400 lb. of dry matter per acre at each grazing. The mean crude protein of the herbage dry matter was 17.4% in 1956 and 14.1% in 1957.
The mean daily liveweight-gains of the calves from birth to 20 weeks of age were 1.05 lb. for the unsupplemented calves and 1.14 lb. for the supplemented ones—a non-significant difference, as was also the difference between the mean increases in belly-girth measurements of the two groups.
Parasitic infestation of the two groups was extremely low and 83% of all faeces samples examined contained no worm eggs.
The latest-born calves made the poorest liveweight gains.
The outdoor rearing of calves is discussed.  相似文献   

14.
In two 20-week grazing experiments, a rigid rotational system of grazing termed the ‘Wye College’ system was compared with a flexible paddock-grazing system in 1972 and with strip grazing and set-stocking in 1973. Eight spring calved Ayrshire cows were used on each treatment at a stocking rate of 5 cows/ha (2 cows/ac). The mean daily milk yields per cow were 17·7 and 17·0 kg(39·0 and 37·5 Ib) on the Wye College and the paddock systems, respectively, in 1972; and 17·9, 17·7 and 16·4 kg (39·4, 38·9 and 36·2 Ib) on the Wye College, strip, and set-stocking systems in 1973. The average annual output of milk varied from 11,500 kg/ha (1030 gal/ac) on the set-stocking system to 12,500 kg ha (1120 gal/ac) on the Wye College system, but none of the differences was significant. The most rapid decline in daily milk yield occurred on the set-stocking system in August and September as the amount of available herbage declined. This system requires further investigation. It is concluded that the Wye College system, with its rigid and pre-determined grazing cycle was as effective as either a one-day paddock or a daily strip-grazing system in producing high yields of milk.  相似文献   

15.
This experiment was carried out to study the responses of sward components (particularly white clover, Trifolium repens ) to grazing management in a natural sward dominated by smooth-stalked meadowgrass ( Poa pratensis ) syn. Kentucky bluegrass. Treatments during two grazing seasons (1989–90) were: cattle grazing alone (C); cattle grazing followed by topping (CT); cattle grazing followed by sheep grazing (CS); and sheep grazing alone (S). Mean target pre- and post-grazing herbage masses were 2200 and 1100 kg DM ha−1, estimated by single-probe electronic capacitance meter. Sward component dynamics were monitored using turf dissections, marked white clover stolons, and ring-toss white clover leaf counts. Component and sward data for the C, CT, CS and S treatments respectively, were: number of white clover leaves m−2, 1295, 1384, 1408, 900 (s.e. ± 108); number of leaves per growing point, 3·2, 3·4, 3·0, 2·8 (s.e. ± 0·2); herbage accumulation (t DM ha−1), 5·16, 5·02, 5·87, 8·28 (s.e. ±0 08); rejected herbage (% pasture area) 39·7, 7·7, 16·0, 0 (s.e. ± 75); and annual net herbage production (t DM ha−1) 3·39, 4·35, 4·99, 8·28 (s.e. ± 0.07). Swards grazed by sheep alone contained less white clover, but regrew quicker and produced more herbage than other treatments. Close topping or grazing by sheep following dairy cattle grazing decreased sward rejection by cattle. These treatments maintained more of the pasture in better condition for subsequent cattle grazing, resulting in greater net herbage production than where no post-cattle grazing treatment was used.  相似文献   

16.
This paper deals with the second three years (April 1954 to March 1957) of a grazing-management trial in the form of a pilot farm. The whole area of 35.5 acres was run as a self-contained unit with the object of providing grazing for as long a period of the year as possible. A system of rotational grazing was used throughout with strip- and fold-grazing at certain seasons. Excess herbage was conserved as silage and hay and fed back to stock during the winter. Beef-type steers and ewes and lambs grazed the pastures, the saleable products being fat cattle, lambs and wool. Results are presented and discussed in relation to stock numbers, animal health, herbage production and botanical composition, fertilizer application and the levels of production achieved. Over-all average fertilizer dressings per acre for the three years were equivalent to 5 cwt. per acre nitro-chalk, 2 cwt. per acre superphosphate and 1 cwt. per acre muriate of potash. The outputs of utilised starch equivalent in 1954–5, 1955–6 and 1956–7 were 2970, 2850 and 2280 1b. per acre, respectively. On the basis of the six years' results it is concluded that high production can be achieved from a system where the object is an extended grazing season; that broadcast leys can be used for winter grazing and the botanical composition of the sward maintained; that self-fed silage can be a satisfactory feed for fattening cattle; that a grazing plan is a valuable guide to management; and that the pilot-farm method is of value for certain agronomic experiments.  相似文献   

17.
An hypothesis relating to the circulation of nitrogen between soil, plants and animals in fertilized grassland is presented. It embodies the results of small-plot experiments and grazing trials on serai grassland in South Africa. Where the value of land is low in comparison with the cost of fertilizer, it is essential that the maximum response be obtained from fertilizer as well as from excretal N. The assumption that 80% of herbage N is returned as excreta, of which 25% is recovered by the grasses in the first season and 25% in the second season, appears to be in accord with liveweight data. Using average values of soil N and fertilizer recovery under local conditions, it is argued that applying 30 lb N per acre (with an initial heavy dressing) should provide higher percentage recoveries of fertilizer N than fixed annual dressings of 60 Ib N per acre. In grazing trials over five years, in which these systems are compared, the apparent recoveries of fertilizer N in animal liveweight were respectively 22.4% and 11.6%.
A distinction is drawn between the initial build-up of nitrogen in circulation and the long term maintenance of a nitrogen level providing maximum recovery of fertilizer N.  相似文献   

18.
In an experiment on the effect of feeding concentrates to spring-calved Ayrshire cows grazing leafy pasture 2 treatments were compared. On the control treatment the sole feed of the cows from M ay to October was grazed herbage. On the supplement treatment the cows grazed the same pasture as the control animals, but in addition were fed concentrates at an average rate oi 21 lb per 10 lb milk. Milk yields on the two treatments were not significantly ditferent, either during the summer feeding period or for the complete lactation. The lengths of the lactations and the fat and S.N.F. contents of the milk were not significantly affected by the treatments. The margin between the value of the milk and the cost of the concentrates was reduced significantly by £13 per cow for the complete lactation as a result of feeding the supplements. It is concluded that at the present price of concentrates and value of milk there are no economic advantages to be gained by feeding supplementary concentrates to spring-calved cows if ample herbage of leafy quality is available.  相似文献   

19.
Masham ewes, stocked at 20 ewes ha−1, reared twins at pasture in 1979 and 1980 and were rotationally grazed around six paddocks. There were three lengths of grazing cycle (18, 30 or 42 d) and the ewes at pasture were either offered silage ad libitum (S) for 8 weeks of lactation or they were not supplemented with silage (N). By feeding silage, S ewes and lambs moved into greater herbage masses (3735 u. 3390 kg organic matter (OM) ha−1), but there was little effect on net herbage accumulation (10.5 v. 10.0 t OM ha−1) and herbage intakes per ewe were similar (2.31 v . 2.27 kg OM d−1) over the 7-month grazing season. During the period of silage supplementation, total intake was 19% higher for S than N ewes, lamb growth rates were slightly higher (280 v . 273 g d−1) and the ewes lost less weight (−78 v −96 g d−1).
For 18-, 30- and 42-d grazing cycles respectively the herbage masses before grazing were 2825, 3620 and 4240 kg OM ha−1; net herbage accumulations were 9.8, 10.4 and 10.6 t OM ha−1; mean daily herbage intakes by each unit (ewe+lambs) were 2.22, 2.35 and 2.30 kg OM and lamb growth rates from birth to weaning at 20 weeks were 205, 204 and 204 g d−1.
Frequent grazing of relatively light herbage masses or infrequent defoliation of heavier herbage masses made little difference to sward or animal performance. It is concluded that, at this stocking rate, different grazing cycles of 18, 30 or 42 d do not affect the performance of lactating ewes.  相似文献   

20.
Sodium fluorescein (SF) was evaluated and validated as an internal marker in cattle for the location of urine patches in pastures. Three trials were carried out aiming at the following: evaluating the effect of dilution and volume of application on SF fluorescence on the environment; testing dosages and duration of excretion of SF administered orally to cattle; and validating the methodology for SF use on the location of cattle urine patches in pastures. The marker was tested in beef cattle kept on pastures under three grazing systems: degraded pasture under extensive management (De), intensively managed dryland pasture with high stocking rate (Id) and intensively managed irrigated pasture with high stocking rate (Ii). Besides the localization of urination sites, the number of urinations/animal/d and the area covered by urine were also determined. The residue of SF remained fluorescent in the pasture foliage up to 34 h after urination events, allowing the location of urine patches by a black‐light flashlight. There was no difference between grazing systems in the number of urine patches/animal/d during the rainy and dry seasons. The average number of urine patches was approximately 11/animal/d. As expected, the estimated volume and area covered by urine varied according to the stocking density. The chosen SF dose (50 mg kg?1 LW) did not adversely affect the animals when administered once daily during 2 d. However, the same SF dose administered during four consecutive days caused urinary disorder in the animal. The distribution of urine patches was spatially dependent on specific characteristics of the paddock.  相似文献   

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