ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01562.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01563.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractSix red clover cultivars, three diploid—Essex, Sabtoron and Violetta—and three tetraploid— Teroba, Red Head and Hungaropoly—were sown alone and with each of three companion grasses—timothy (S48), tall fescue (S170) and perennial ryegrass (S24). The productivity and persistency of the red clover cultivars were compared over 4 years. Dry matter (DM) yield, DM digestibility and the crude protein (CP) concentration were assessed and botanical analyses conducted on herbage samples from each treatment at each of three harvests per annum. Annual fertilizer application consisted of 165 kg P and 312 kg K ha‐1.Comparing clover cultivars alone Essex was significantly less productive and less persistent than the other five cultivars. Yield and persistency of the five other cultivars did not differ markedly within years with the exception that the diploids were significantly less productive than the tetraploids in the fourth year. Over all 4 years mean annual total DM and clover DM yields of the five cultivars were between 12·2 and 13·2 t ha‐1and between 9·2 (79·2% of total DM yield) and 10·2 (83·2%) t ha‐1respectively, and differences were not significant.Up to the end of the third year there was little or no advantage gained by the inclusion of a companion grass, annual total DM yields being between 11·2 and 14·2 t ha‐1for clover alone and between 10·2 and 14·2 t ha‐1for clover‐grass mixtures. In the fourth year there was an overall tendency for the yield of the clover alone to be lower, between 7·2 and 12·2 t ha‐1, than that of the clover‐grass mixture, between 8·2 and 13·2 t ha‐1, and this was more pronounced with the diploid than with the tetraploid clover cultivars. Sown with companion grasses, Essex and Hungaropoly were lower in yield and in contribution than the other cultivars over the 4 years. The influence of the companion grass on total dry matter yield showed that the contribution of timothy was low relative to that made by tall fescue and perennial ryegrass. Perennial ryegrass made the most varied contribution from year to year. Tall fescue was the most consistent contributor with all clover cultivars and at the end of 4 years both yield and clover‐grass balance had not changed materially.No pronounced differences in DM digestibility were evident between treatments.Crude protein concentration of the pure clover was similar to that of the clover‐timothy treatments and both would appear to be superior to either the clover‐perennial ryegrass or clover‐tall fescue mixtures.It is considered that red clover dominant swards are suitable for use under a cutting regime and can provide high yields of DM at a low cost for up to 4 years. Such swards are self‐sufficient in N and in addition soil N accumulation can

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01564.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA novel hybrid stubble turnip, Appin, bred by the Scottish Plant Breeding Station (Brassica campestrisssp.rapiferacv. Tigra ×B. campestrisssp.nipposinicacv. Mizuna) was compared in small‐plot cutting trials with stubble turnip (B. campestrisssp.rapiferacv. Ponda), forage rape (B. napusssp.bienniscv. Canard) and fodder radish (Raphinus sativuscv. Neris) for 3 years, 1975–77, samples being taken from October to December or January each year to cover the likely period of utilization by grazing lambs. Except for the first year, Appin proved to yield less DM than Ponda, and be inferior in digestibility and metabolizable energy (ME) content, though N contents were on occasion higher. Canard had the highest overall ME content. In dry conditions in autumn 1977, Ponda proved the more reliable crop, suffering less depression in yield than other species. Anti‐metabolite contents were determined in freeze‐dried samples taken in winter 1976‐77 and showed Canard to have the most brassica anaemia factor (S‐methyl cysteine sulphoxide): contents of thiocyanate were generally similar between crops.As the degree of utilization of such forages when grazed can outweigh differences in recorded above‐ground DM yields from cutting trials, it was considered that claims of better root anchorage and hence better utilization for Appin warranted evaluation in a

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01565.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractAn established sward of red clover cv. Hungaropoly sown pure received approx. 30 kg P ha‐1and 200 kg K ha‐1each year for 3 successive years. The P and K were applied either as cattle slurry, inorganic fertilizer or combinations of these. Treatments were applied either in spring or after the first harvest. There were a total of six treatments and these were harvested three times each year. The average yields of total herbage DM over all the treatments in the first, second and third years were 15·2, 14·2 and 14·2 t ha‐1respectively and the various treatments had no significant effect on the overall yields.Treatments had a significnt effect on red clover DM yields and percentage red clover in one harvest in each of the first 2 years and all three in the third year. Yields of red clover were lower and grass higher in treatments receiving cattle slurry only. On this treatment there was a total yield of 23·2 t ha‐1red clover DM in the 3 years compared with 30·2 t ha‐1on the inorganic fertilizer treatments. However, by applying P and K fertilizer in the spring, followed by cattle slurry after the first harvest, it was possible to maintain a high proportion of red clover in the sward and to produce yields of red clover DM similar to those on the inorganic fertili

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01566.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA mathematical model which simulates the response of grass to irrigation over a range of rainfall and soil conditions is described. Using the model the probable costs and benefits from investing in irrigation facilities for intensive beef and dairy production have been determined. Irrigation only appears to show a reasonable return on investment where the mean summer rainfall is less than 350 mm or the water‐retaining capacity of the soil is low. Furthermore, investment in irrigation is only likely to be logical where the rate of fertilizer N applied is greater than 300 kg N ha‐1. It also appears that a strategy of partial irrigation is unlikely to yield the maximum financial gain. Overall the indications are that for the foreseeable future only a small percentage of the total grassland area in the UK can be irrigated profita

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01567.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe effects of severity of grazing on the herbage intake and milk production of continuously stocked British Friesian cows calving in February–March were examined in three experiments conducted in the years 1976–78 (experiments 1–3 respectively) using a put‐and‐take technique. In experiment 1 four grazing severities were imposed by maintaining swards with different herbage masses (2500, 3000, 3500, 4000 kg OM ha‐1); in experiments 2 and 3 there were two severities of grazing maintained by keeping swards canopies at constant heights of 5 and 7 cm (experiment 2) and 5 and 7·2 cm (experiment 3). Cows were reallocated to treatment every 8 weeks in experiments 1 and 2 and there were three periods, whereas they all grazed throughout a 23‐week period on the same treatment in the final trial.A decrease in the quantity of herbage on offer or in sward height reduced herbage intake and milk production in all experiments. Mean daily herbage OM intakes were 11·2, 12·2, 12·2 and 12·2 kg respectively in experiment 1, 12·2 and 13·2 kg respectively in experiment 2 and 12·2 and 152 kg respectively in experiment 3. Mean daily solids–corrected milk yields were 14·2, 15·2, 15·2 and 16·2 kg respectively in experiment 1, 14·2 and 16·2 kg respectively in experiment 2 and 12·2 and 17·2 kg respectively in experiment 3. It was apparent from the data obtained in the first two trials that grazing at a sward canopy height of 7 rather than 9 cm had little effect, but that at 5 cm there were significant depressions in both herbage intake and milk production. Milk yield was depressed to a greater extent when cows were kept on the same

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01568.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractTwo grass silages made from perennial ryegrass, and with D‐values of 0·216 and 0·255, were offeredad libitumto 18 Ayrshire cows in two feeding experiments. On the control treatment the silages were supplemented with soybean meal only, and on the other two treatments with equal weights of DM from either barley or dried molassed sugar‐beet pulp plus the same weight of soya as on the control treatment. The daily intakes of silage DM were not significantly different on the barley and beet‐pulp treatments, and, on average, the intake of silage DM was reduced by 0·24 and 0·20 kg by feeding 1 kg barley and beet pulp DM respectively.The daily milk yields were not significantly different on the barley and beet‐pulp treatments with mean values of 19·2 and 19·2 kg per cow respectively compared with 17·2 kg on the control treatment. On the barley and beet‐pulp treatments the fat, SNF, CP and lactose concentrations in the milk and the live weights of the cows were not significantly different. It is concluded that the barley and beet pulp had similar feeding values and replacement rates when used as supplements with grass silage, and that the two feeds were interchangeable on a

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01569.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Book review in this articlePhysiological and Environmental Limitations to Wool GrowthProceedings of a National Workshop, Leura, New South Wales, Australia, April 1978Edited by J. L. Black and P. J. ReisEcology of the English ChalkBy C. J. SmithRange Science: A Guide to Information SourcesEdited by J. F. Vallentine and P. L. SimsGrass: its Production and UtilizationEdited by W. HolmesGrassland in the British EconomyEdited by J. L. JollansProceedings of the XIII International Grassland Congress, Leipzig, German Democratic Republic, 18‐27 May 1977Edited by E. Wojahn and H. Th

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1981.tb01570.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY