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E. A. Hunter - One of the best experts on this subject based on the ideXlab platform.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights. 3. Sward characteristics and animal output, years 4-8
Grass and Forage Science, 1997Co-Authors: J. E. Vipond, G. Swift, A. T. Cleland, J. Fitzsimons, E. A. HunterAbstract:Results for years 4–8 of a long-term grazing experiment on Swards of a diploid perennial ryegrass (Lolium perenne), var. Contender (D Swards), a tetraploid ryegrass, var. Condesa (T Swards) and Condesa with S184 white clover (Trifolium repens) (TC Swards), direct sown in May 1987, are presented. The Swards were continuously stocked with sheep from 1988 to 1990, as previously reported, and for a further 5 years, 1991–95, at a target Sward surface height (SSH) of 4–6 cm. Control of Sward height was successfully achieved by variable stocking, except in 1993 when paddocks were set stocked and the resulting mean SSH was 9·3 cm. Grass Swards received on average 160 kg N ha−1 year−1; grass/clover Swards were mainly not fertilized with N with the exception that they were given 30 kg N ha−1 as a remedial mid-summer application during a period of low herbage mass on offer in 1994 and 1995. Mean white clover content of the Swards fell from 18·2% of herbage dry-matter (DM) in 1992 to 8·5% in 1993, whereas stolon lengths fell from 120 to 58 m m−2. A return to lower Sward heights in 1994–95 resulted in an increase in white clover content to 12·8% by the final sampling in August 1995. Perennial ryegrass content of the grass Swards remained high throughout (mean 96·7% in 1995). Perennial ryegrass tiller densities recorded in August 1991, 1993 and 1994 showed consistently significant (P < 0·001) Sward differences (3-year mean 16 600, 13 700 and 10 100 perennial ryegrass tillers m−2 for the D, T and TC Swards). In 1994, the year after lax grazing, a low perennial ryegrass tiller density (9100 m−2) and low white clover content (mean 4·3%) in the TC Swards resulted in a much lower herbage bulk density than in the grass Swards (April–July means 72, 94 and 44 kg OM ha−1 cm−1 for the D, T and TC Swards). There was a consistent 40 g d−1 increase in lamb liveweight gain on the TC Swards over the T Swards, except in 1994. In that year there was a reduction in lamb liveweight gain of 33 g d−1 on the TC Swards and a significant increase in ewe liveweight loss (117 g d−1) associated with low herbage bulk density despite optimal Sward height. Lamb output (kg liveweight ha−1) on TC Swards reflected white clover content, falling from a similar output to that produced from grass given 160 kg N ha−1, at 18% white clover DM content, down to 60% of grass + N Swards with around 5% clover. A 6% greater output from the T than the D Swards was achieved mainly through higher stocking rate. The experiment demonstrated a rapid, loss in white clover under lax grazing, and showed that the relationship between performance and Sward height is also dependent on herbage density. High lamb output from a grass/clover Sward was only achieved when the clover content was maintained at 15–20% of the herbage DM.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights: 1. Sward characteristics
Grass and Forage Science, 1993Co-Authors: J. E. Vipond, G. Swift, J. Fitzsimons, J. A. Milne, T.h. Mcclelland, E. A. HunterAbstract:Performance of continuously stocked Mule ewes nursing Suffolk-cross twin lambs over three grazing seasons, between April and August, was compared on Swards of N-fertilized diploid perennial ryegrass (D), tetraploid perennial ryegrass (T) and tetraploid perennial ryegrass with white clover (TC), the latter receiving no fertilizer N. Sward height was maintained by variable stocking rate close to a target of 4–6 cm (constant treatment) from turnout and compared in July and August with a rising Sward height treatment (target 6–8 cm). Lambs on TC Swards had significantly higher (P
Jean-louis Peyraud - One of the best experts on this subject based on the ideXlab platform.
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lnterest of multi-species Swards for pasture-based milk production systems
2014Co-Authors: Ana Isabel Roca Fernandez, Luc Delaby, Jean-louis Peyraud, Jacques Lassalas, Remy DelagardeAbstract:The objective of this 2-year study was to determine the potential ofmulti-species Swards (MSS) for making secure forage availability in grazing dairy systems, and for increasing milk production on a per-ha basis. Four types of Sward with increasing number of Sward species (fi-om pure perennial ryegrass to a mixture of five species including perennial ryegrass, two clovers, chicory and tall fescue) were compared with four block replicates. Treatments within blocks were simultaneously grazed by four homogeneous dairy herds at the same pasture allowance. Total grazing days per season or per year were unaffected by treatment, but milk output per ha was greater for grass-legume mixtures and MSS compared to pure perennial ryegrass Swards. This was related to greater milk production per cow and per day. It is concluded that, under favourable weather conditions particularly in late spring and early summer, advantages of MSS on milk output on a per-ha basis are main! y due to an improved per-cow production rather than to increased pasture herbage production and grazing days/ ha.
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Foraging behavior and ruminal fermentation of dairy cows grazing ryegrass pasture alone or with white clover
Pesquisa Agropecuária Brasileira, 2012Co-Authors: Henrique Mendonça Nunes Ribeiro Filho, Jean-louis Peyraud, Remy DelagardeAbstract:The objective of this work was to evaluate the influence of pasture composition and regrowth age on the relationship between feeding behavior and ruminal fermentation in dairy cows grazing perennial ryegrass with or without white clover. The experiment was carried out in a 2x2 factorial arrangement, with two Sward types and two ages of regrowth. Swards of perennial ryegrass sown alone (PRG) and of perennial ryegrass mixed with white clover (GC) were evaluated. Twelve late-lactation Holstein cows, fistulated at the rumen, were distributed in a 4x4 latin square experimental design with four 12-day periods. Daily distribution of grazing was similar in the PRG and the GC Swards, but the concentration of rumen volatile fatty acids (VFA) was higher and the proportion of propionate was lower on mixed Swards during the day. Daily distribution of grazing was similar in pastures of different ages. However, in the oldest Swards, rumen fluid pH increased and VFA concentration decreased after evening milking. Time spent grazing does not influence ruminal fermentation, which depends on the changes that occur as different Sward layers are grazed.
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herbage intake and milk yield of dairy cows grazing perennial ryegrass Swards or white clover perennial ryegrass Swards at low and medium herbage allowances
Animal Feed Science and Technology, 2005Co-Authors: H Ribeiro M N Filho, Remy Delagarde, Jean-louis PeyraudAbstract:Abstract Including legumes in grass Swards generally increases nutrient intake and performance of grazing cattle. The objective of this study was to determine if the difference in herbage intake of dairy cows grazing either perennial ryegrass Swards (PRG) or white clover/perennial ryegrass Swards (GC) is a function of herbage allowance. Both Sward types were compared at 20 or 35 kg DM/cow/day offered at ground level according to a 4 × 4 Latin square design with four 10-day periods and with 24 Holstein cows in mid-lactation. Clover represented on average 270 g/kg of live DM material in GC Swards. Pre-grazing herbage mass at ground level did not differ between Sward types but pre-grazing herbage mass above 5 cm and Sward height was much lower on GC than on PRG Swards. There was no interaction between Sward type and herbage allowance on herbage intake and milk yield. Cows grazing on GC Swards had lower herbage intake (−0.7 kg OM/day), OM digestibility of the selected herbage (−20 g/kg OM) and milk yield (−1.3 kg/day) than cows grazing on PRG Swards. Milk fat content was unaffected by Sward type and milk protein content was lower on GC than on PRG Swards. Herbage intake, herbage OM digestibility, milk yield and milk protein content increased, and milk fat content decreased, with increasing herbage allowance. It is concluded that including white clover in perennial ryegrass Swards, along with suppressing nitrogen fertilisation, did not improve herbage intake or milk production when this is associated with a sharp decrease in Sward height and herbage mass in the upper strata of the Sward.
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Herbage intake and milk yield of dairy cows grazing perennial ryegrass Swards or white clover/perennial ryegrass Swards at low- and medium-herbage allowances
Animal Feed Science and Technology, 2005Co-Authors: H. M. N. Ribeiro Filho, Remy Delagarde, Jean-louis PeyraudAbstract:Abstract Including legumes in grass Swards generally increases nutrient intake and performance of grazing cattle. The objective of this study was to determine if the difference in herbage intake of dairy cows grazing either perennial ryegrass Swards (PRG) or white clover/perennial ryegrass Swards (GC) is a function of herbage allowance. Both Sward types were compared at 20 or 35 kg DM/cow/day offered at ground level according to a 4 × 4 Latin square design with four 10-day periods and with 24 Holstein cows in mid-lactation. Clover represented on average 270 g/kg of live DM material in GC Swards. Pre-grazing herbage mass at ground level did not differ between Sward types but pre-grazing herbage mass above 5 cm and Sward height was much lower on GC than on PRG Swards. There was no interaction between Sward type and herbage allowance on herbage intake and milk yield. Cows grazing on GC Swards had lower herbage intake (−0.7 kg OM/day), OM digestibility of the selected herbage (−20 g/kg OM) and milk yield (−1.3 kg/day) than cows grazing on PRG Swards. Milk fat content was unaffected by Sward type and milk protein content was lower on GC than on PRG Swards. Herbage intake, herbage OM digestibility, milk yield and milk protein content increased, and milk fat content decreased, with increasing herbage allowance. It is concluded that including white clover in perennial ryegrass Swards, along with suppressing nitrogen fertilisation, did not improve herbage intake or milk production when this is associated with a sharp decrease in Sward height and herbage mass in the upper strata of the Sward.
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Inclusion of white clover in strip-grazed perennial ryegrass Swards: herbage intake and milk yield of dairy cows at different ages of Sward regrowth
Animal Science, 2003Co-Authors: H. M. N. Ribeiro Filho, Remy Delagarde, Jean-louis PeyraudAbstract:AbstractThe introduction of legumes in grass-based Swards provides some economic and agronomic advantages, often allowing an increase in the performance of grazing ruminants. The aim of this study was to obtain a better quantification of the nutritional benefits to dairy cows after introducing white clover into Swards of perennial ryegrass (PRG), using two ages of regrowth. Four treatments were studied in a 2 ✕ 2 factorial design with two Sward types and two ages of regrowth. The Swards were either a pure perennial ryegrass Sward with nitrogen (N) fertilization, or a perennial ryegrass/white clover mixture (GC) with no N fertilization. The regrowth ages were 19 and 35 days (treatments: PRG19, PRG35, GC19 and GC35). The proportion of clover in the GC Swards was on average 420 g/kg dry matter (DM). Twelve late-lactation Holstein cows, fistulated at the rumen and duodenum, were used according to a 4 ✕ 4 Latin-square design with four 11-day periods. The pasture was strip-grazed with 12 kg DM per cow of herbage above 5 cm offered daily in all the treatments.The effects of Sward type and regrowth age were often additive, in particular for herbage intake and milk yield. Herbage organic matter (OM) intake, duodenal non-ammonia N (NAN) flow and milk yields were higher on the GC Swards and lower on the older regrowths. Finally, the performance of the cows was similar on the PRG19 and GC35 treatments. The OM digestibility of the selected herbage as well as the duodenal nitrogen flux per kg digestible OM intake was not affected by the Sward type. Ruminal fermentations were more intense with mixed Swards and the youngest regrowths. The daily grazing time and the daily pattern of grazing activities were modified by the type of Sward and by regrowth age. The average OM intake rate was higher on the GC Swards than on the PRG Swards. In this study, the nutritional advantage of introducing white clover into Swards of perennial ryegrass was related to an increase in herbage intake and not to any improvement in the nutritive value of the Sward.
J. E. Vipond - One of the best experts on this subject based on the ideXlab platform.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights. 3. Sward characteristics and animal output, years 4-8
Grass and Forage Science, 1997Co-Authors: J. E. Vipond, G. Swift, A. T. Cleland, J. Fitzsimons, E. A. HunterAbstract:Results for years 4–8 of a long-term grazing experiment on Swards of a diploid perennial ryegrass (Lolium perenne), var. Contender (D Swards), a tetraploid ryegrass, var. Condesa (T Swards) and Condesa with S184 white clover (Trifolium repens) (TC Swards), direct sown in May 1987, are presented. The Swards were continuously stocked with sheep from 1988 to 1990, as previously reported, and for a further 5 years, 1991–95, at a target Sward surface height (SSH) of 4–6 cm. Control of Sward height was successfully achieved by variable stocking, except in 1993 when paddocks were set stocked and the resulting mean SSH was 9·3 cm. Grass Swards received on average 160 kg N ha−1 year−1; grass/clover Swards were mainly not fertilized with N with the exception that they were given 30 kg N ha−1 as a remedial mid-summer application during a period of low herbage mass on offer in 1994 and 1995. Mean white clover content of the Swards fell from 18·2% of herbage dry-matter (DM) in 1992 to 8·5% in 1993, whereas stolon lengths fell from 120 to 58 m m−2. A return to lower Sward heights in 1994–95 resulted in an increase in white clover content to 12·8% by the final sampling in August 1995. Perennial ryegrass content of the grass Swards remained high throughout (mean 96·7% in 1995). Perennial ryegrass tiller densities recorded in August 1991, 1993 and 1994 showed consistently significant (P < 0·001) Sward differences (3-year mean 16 600, 13 700 and 10 100 perennial ryegrass tillers m−2 for the D, T and TC Swards). In 1994, the year after lax grazing, a low perennial ryegrass tiller density (9100 m−2) and low white clover content (mean 4·3%) in the TC Swards resulted in a much lower herbage bulk density than in the grass Swards (April–July means 72, 94 and 44 kg OM ha−1 cm−1 for the D, T and TC Swards). There was a consistent 40 g d−1 increase in lamb liveweight gain on the TC Swards over the T Swards, except in 1994. In that year there was a reduction in lamb liveweight gain of 33 g d−1 on the TC Swards and a significant increase in ewe liveweight loss (117 g d−1) associated with low herbage bulk density despite optimal Sward height. Lamb output (kg liveweight ha−1) on TC Swards reflected white clover content, falling from a similar output to that produced from grass given 160 kg N ha−1, at 18% white clover DM content, down to 60% of grass + N Swards with around 5% clover. A 6% greater output from the T than the D Swards was achieved mainly through higher stocking rate. The experiment demonstrated a rapid, loss in white clover under lax grazing, and showed that the relationship between performance and Sward height is also dependent on herbage density. High lamb output from a grass/clover Sward was only achieved when the clover content was maintained at 15–20% of the herbage DM.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights: 1. Sward characteristics
Grass and Forage Science, 1993Co-Authors: J. E. Vipond, G. Swift, J. Fitzsimons, J. A. Milne, T.h. Mcclelland, E. A. HunterAbstract:Performance of continuously stocked Mule ewes nursing Suffolk-cross twin lambs over three grazing seasons, between April and August, was compared on Swards of N-fertilized diploid perennial ryegrass (D), tetraploid perennial ryegrass (T) and tetraploid perennial ryegrass with white clover (TC), the latter receiving no fertilizer N. Sward height was maintained by variable stocking rate close to a target of 4–6 cm (constant treatment) from turnout and compared in July and August with a rising Sward height treatment (target 6–8 cm). Lambs on TC Swards had significantly higher (P
G. Swift - One of the best experts on this subject based on the ideXlab platform.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights. 3. Sward characteristics and animal output, years 4-8
Grass and Forage Science, 1997Co-Authors: J. E. Vipond, G. Swift, A. T. Cleland, J. Fitzsimons, E. A. HunterAbstract:Results for years 4–8 of a long-term grazing experiment on Swards of a diploid perennial ryegrass (Lolium perenne), var. Contender (D Swards), a tetraploid ryegrass, var. Condesa (T Swards) and Condesa with S184 white clover (Trifolium repens) (TC Swards), direct sown in May 1987, are presented. The Swards were continuously stocked with sheep from 1988 to 1990, as previously reported, and for a further 5 years, 1991–95, at a target Sward surface height (SSH) of 4–6 cm. Control of Sward height was successfully achieved by variable stocking, except in 1993 when paddocks were set stocked and the resulting mean SSH was 9·3 cm. Grass Swards received on average 160 kg N ha−1 year−1; grass/clover Swards were mainly not fertilized with N with the exception that they were given 30 kg N ha−1 as a remedial mid-summer application during a period of low herbage mass on offer in 1994 and 1995. Mean white clover content of the Swards fell from 18·2% of herbage dry-matter (DM) in 1992 to 8·5% in 1993, whereas stolon lengths fell from 120 to 58 m m−2. A return to lower Sward heights in 1994–95 resulted in an increase in white clover content to 12·8% by the final sampling in August 1995. Perennial ryegrass content of the grass Swards remained high throughout (mean 96·7% in 1995). Perennial ryegrass tiller densities recorded in August 1991, 1993 and 1994 showed consistently significant (P < 0·001) Sward differences (3-year mean 16 600, 13 700 and 10 100 perennial ryegrass tillers m−2 for the D, T and TC Swards). In 1994, the year after lax grazing, a low perennial ryegrass tiller density (9100 m−2) and low white clover content (mean 4·3%) in the TC Swards resulted in a much lower herbage bulk density than in the grass Swards (April–July means 72, 94 and 44 kg OM ha−1 cm−1 for the D, T and TC Swards). There was a consistent 40 g d−1 increase in lamb liveweight gain on the TC Swards over the T Swards, except in 1994. In that year there was a reduction in lamb liveweight gain of 33 g d−1 on the TC Swards and a significant increase in ewe liveweight loss (117 g d−1) associated with low herbage bulk density despite optimal Sward height. Lamb output (kg liveweight ha−1) on TC Swards reflected white clover content, falling from a similar output to that produced from grass given 160 kg N ha−1, at 18% white clover DM content, down to 60% of grass + N Swards with around 5% clover. A 6% greater output from the T than the D Swards was achieved mainly through higher stocking rate. The experiment demonstrated a rapid, loss in white clover under lax grazing, and showed that the relationship between performance and Sward height is also dependent on herbage density. High lamb output from a grass/clover Sward was only achieved when the clover content was maintained at 15–20% of the herbage DM.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights: 1. Sward characteristics
Grass and Forage Science, 1993Co-Authors: J. E. Vipond, G. Swift, J. Fitzsimons, J. A. Milne, T.h. Mcclelland, E. A. HunterAbstract:Performance of continuously stocked Mule ewes nursing Suffolk-cross twin lambs over three grazing seasons, between April and August, was compared on Swards of N-fertilized diploid perennial ryegrass (D), tetraploid perennial ryegrass (T) and tetraploid perennial ryegrass with white clover (TC), the latter receiving no fertilizer N. Sward height was maintained by variable stocking rate close to a target of 4–6 cm (constant treatment) from turnout and compared in July and August with a rising Sward height treatment (target 6–8 cm). Lambs on TC Swards had significantly higher (P
J. Fitzsimons - One of the best experts on this subject based on the ideXlab platform.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights. 3. Sward characteristics and animal output, years 4-8
Grass and Forage Science, 1997Co-Authors: J. E. Vipond, G. Swift, A. T. Cleland, J. Fitzsimons, E. A. HunterAbstract:Results for years 4–8 of a long-term grazing experiment on Swards of a diploid perennial ryegrass (Lolium perenne), var. Contender (D Swards), a tetraploid ryegrass, var. Condesa (T Swards) and Condesa with S184 white clover (Trifolium repens) (TC Swards), direct sown in May 1987, are presented. The Swards were continuously stocked with sheep from 1988 to 1990, as previously reported, and for a further 5 years, 1991–95, at a target Sward surface height (SSH) of 4–6 cm. Control of Sward height was successfully achieved by variable stocking, except in 1993 when paddocks were set stocked and the resulting mean SSH was 9·3 cm. Grass Swards received on average 160 kg N ha−1 year−1; grass/clover Swards were mainly not fertilized with N with the exception that they were given 30 kg N ha−1 as a remedial mid-summer application during a period of low herbage mass on offer in 1994 and 1995. Mean white clover content of the Swards fell from 18·2% of herbage dry-matter (DM) in 1992 to 8·5% in 1993, whereas stolon lengths fell from 120 to 58 m m−2. A return to lower Sward heights in 1994–95 resulted in an increase in white clover content to 12·8% by the final sampling in August 1995. Perennial ryegrass content of the grass Swards remained high throughout (mean 96·7% in 1995). Perennial ryegrass tiller densities recorded in August 1991, 1993 and 1994 showed consistently significant (P < 0·001) Sward differences (3-year mean 16 600, 13 700 and 10 100 perennial ryegrass tillers m−2 for the D, T and TC Swards). In 1994, the year after lax grazing, a low perennial ryegrass tiller density (9100 m−2) and low white clover content (mean 4·3%) in the TC Swards resulted in a much lower herbage bulk density than in the grass Swards (April–July means 72, 94 and 44 kg OM ha−1 cm−1 for the D, T and TC Swards). There was a consistent 40 g d−1 increase in lamb liveweight gain on the TC Swards over the T Swards, except in 1994. In that year there was a reduction in lamb liveweight gain of 33 g d−1 on the TC Swards and a significant increase in ewe liveweight loss (117 g d−1) associated with low herbage bulk density despite optimal Sward height. Lamb output (kg liveweight ha−1) on TC Swards reflected white clover content, falling from a similar output to that produced from grass given 160 kg N ha−1, at 18% white clover DM content, down to 60% of grass + N Swards with around 5% clover. A 6% greater output from the T than the D Swards was achieved mainly through higher stocking rate. The experiment demonstrated a rapid, loss in white clover under lax grazing, and showed that the relationship between performance and Sward height is also dependent on herbage density. High lamb output from a grass/clover Sward was only achieved when the clover content was maintained at 15–20% of the herbage DM.
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A comparison of diploid and tetraploid perennial ryegrass and tetraploid ryegrass/white clover Swards under continuous sheep stocking at controlled Sward heights: 1. Sward characteristics
Grass and Forage Science, 1993Co-Authors: J. E. Vipond, G. Swift, J. Fitzsimons, J. A. Milne, T.h. Mcclelland, E. A. HunterAbstract:Performance of continuously stocked Mule ewes nursing Suffolk-cross twin lambs over three grazing seasons, between April and August, was compared on Swards of N-fertilized diploid perennial ryegrass (D), tetraploid perennial ryegrass (T) and tetraploid perennial ryegrass with white clover (TC), the latter receiving no fertilizer N. Sward height was maintained by variable stocking rate close to a target of 4–6 cm (constant treatment) from turnout and compared in July and August with a rising Sward height treatment (target 6–8 cm). Lambs on TC Swards had significantly higher (P
