The Effects of Level of Nitrogen Fertilizer on Beef Production From Grazed Perennial Ryegrass/White–clover Pastures

Self Cite

The treatments in this summer-grazing experiment were designed as a 2 x 3 factorial, there being two levels of nitrogenous fertilizer (nitro-chalk), supplying 0 and 336 kg of N/ha per annum (NO and N3, respectively) and three stocking rates. The fertilizer was applied in 7 dressings at approximately three-weekly intervals. The animals used were Hereford x Friesian steers; these were slaughtered at the end of the grazing season. The stocking rates were calculated on the basis of expected herbage production. The experiment was laid out in 6 randomized blocks which were grazed in rotation. Two blocks were cut for conservation before grazing each year; up to the end of June only 4 blocks were used for grazing. There was little contamination of the swards with unsown species. With the NO swards the clover contents declined each year, but remained fairly high at over 20% in 1965. Clover contents also declined each year in the N3 swards and by 1965 were only 2 to 4%. The quantities of herbage cut for conservation were higher from the swards receiving N. The live-weight gains of the cattle (per head) were higher at the lower stocking rates, the effect of stocking rate being more noticeable in the July to Oct. period. Live-weight gains per ha increased at the higher stocking rates. In 1963 and 1965, as stocking rates increased carcass weights per animal decreased and carcass quality, as indicated by the commercial grades, was poorer. In 1964, a dry spell from July to Oct. necessitated the removal of cattle from the experiment and the effects of treatment on carcass weight and quality were not apparent.

Section: General and Managementmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

The Effects of Level of Nitrogen Fertilizer on Beef Production From Grazed Perennial–ryegrass/White–clover Pastures

Alder

Cowlishaw

Newton

et al. 1968

Self Cite

“…The pastures were laid out in 6 randomized blocks which were grazed in rotation by one group of 4 cattle per treatment, except when blocks were reserved temporarily for conservation. The treatments were designed as a 2x3 factorial, there being two levels of fertilizer input, 0 and 336 kg/ha per year, and three stocking rates designed to give three grazing pressures, low (L), moderate (M) and high (H): The Stocking rate calculation was similar to that used in the earlier experiment (1). N was applied as 21% nitro-chalk, the total of 336 kg/ha being applied in seven dressings at intervals of 3 weeks, approximately.…”

Section: General and Managementmentioning

confidence: 99%

The Effects of Level of Nitrogen Fertilizer on Beef Production From Grazed Perennial Ryegrass/White–clover Pastures

Alder

Cowlishaw

Newton

et al. 1967

Self Cite

The treatments in this summer-grazing experiment were designed as a 3 x 3 factorial; 3 levels of nitrogenous fertilizer, supplying 0, 336 and 672 kg N/ha per annum, and 3 stocking rates. The fertilizer was applied in 6 to 8 dressings at intervals of 3 to 4 weeks. The animals used were fattening Hereford x Friesian steers. The stocking rates were calculated on the basis of data available on herbage production under N and irrigation treatments and varied according to the level of N input. The experiment was laid out in 6 randomized blocks, which were grazed in rotation. Blocks were removed from the grazing cycle in spring and early summer of each of the 3 years (1962-4) over which the experiment was conducted and cut for conservation; yields were recorded. Details are given of: grazing management; results of studies of soil-N levels; the quantities of herbage removed for conservation; the quantity, chemical and botanical composition of the herbage available for grazing; and herbage consumption.

“…Bloat did not occur at any time, although in 1963 during 2 weeks of wet weather in late June and early July cattle showed reluctance to graze areas in one paddock which were red-clover dominant, which suggests a possible connection with the effects of very high clover contents recorded by Alder et al (1). DISCUSSION The validity of the N rate comparisons depends on the stocking rates having been the same relative to the amount of feed available.…”

Section: Botanical Composition Of the Swardmentioning

confidence: 91%

“…The mean liveweight of the cattle in all the experiments used in equation (1) in mid season was approximately 400 kg, which gaining at 0-75 kg/day requires 9-9 kg DM intake/day (16). If one grazing day is equivalent to 0 67 cow-days, then from Table 7 and equation (1): cow-days=540-^0-93x-0 00098xŵ…”

Section: Botanical Composition Of the Swardmentioning

confidence: 99%

The Effect of Nitrogen Application to Pasture on Beef Production

Holmes

Lang

1974

Five graziiig experiments each lasting 2 or 3 years were made between 1955 and 1967, all starting in the first year of ryegrass/cocksfoot/clover or ry^rass/clover leys. A high and a low rate of N, 235 and 45 Ib/ac on average (263 and 51 kg/ha) were compared for beef production. Higb-and low-N treatments gave mean clover contents for the grazing season of 8 and 24 % on a dry-weight basis, respectively. High N consistently gave a smaller liveweigbt gain/animal than low N, on average 192 and 208 Ib/day (0 87 and 094 kg/day), respectively. Liveweigbt gain/ac was 20 % greater for hig^ N than for low N, and in terms of net energy tbe production from bigh-and low-N, respectively, was 18,500 and 15,000 MJ/ac (45,700 and 37,100 MJ/ha). Data from these experiments, together with published results, were used to calculate a regression of liveweight gain response on N rate and an equation was derived from this to express tbe output in terms of profit. At 1971 prices profit was maximal at £0 9/ac (f2/ha) with 112 Ib N/ac (125 kg N/ha); it was considerably greater at 1973 prices wben bigber rates of N were justified.