Effects of spring grazing on dryland perennial ryegrass/white clover dairy pastures. 2. Botanical composition, tiller, and plant densities

2006 ◽  
Vol 57 (5) ◽  
pp. 555 ◽  
Author(s):  
F. R. McKenzie ◽  
J. L. Jacobs ◽  
G. Kearney
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Plant Density ◽  
Grazing Intensity ◽  
Development Stage ◽  
Botanical Composition ◽  
Higher Plant ◽  
Plant Frequency ◽  
Tiller Density ◽  
Over Time

A 3-year experiment (September 1999–August 2002) in south-western Victoria investigated spring grazing impacts on botanical composition, tiller densities (perennial ryegrass, other-grasses, clover growing points, and broad-leaved weeds), and perennial ryegrass plant frequencies of a pasture of perennial ryegrass (Lolium perenne L.)–white clover (Trifolium repens L.) pasture. Spring grazing treatments, applied annually from September to November were based on ryegrass leaf development stage with high (HF), medium (MF), and low (LF) grazing frequency being 2-, 3-, and 4-leaf stage, respectively, and post-grazing height as the grazing intensity with high (HI), medium (MI), and low grazing intensity being 3, 5, and 8 cm, respectively. Five combinations were used: HFHI, LFHI, MFMI, HFLI, and LFLI. A sixth treatment, rapid grazing (RG), maintained pasture between 1500 and 1800 kg DM/ha by grazing weekly during spring and a seventh and eighth treatment, simulating forage conservation for early-cut silage (lock-up for 6–7 weeks; SIL) and late-cut hay (lock up for 11–12 weeks; HAY), were also included. Perennial ryegrass content remained stable in the RG and HFHI treatments, averaging 78 and 75% DM, respectively, and declined in all other treatments. For example, perennial ryegrass content in LFLI declined from 75% (September 1999) to 50% DM (August 2002). RG and HFHI resulted in a slight increase in other grass (e.g. Holcus lanatus and Poa annua) content over time. SIL, LFLI, LFHI, and MFMI resulted in a higher other-grass content than RG and HFHI. LFLI, LFHI, and HFLI resulted in a stable dead (litter) pasture content over time, while SIL, HAY, HFHI, and RG resulted in a decline in dead pasture content over time. For RG and HFHI spring treatments the decline in dead pasture content was greater than LFLI, LFHI, and HFLI spring grazing. Data for white clover and broad-leaved weeds (e.g. Rumex dumosus and Taraxacum officinale) were inconsistent and could not be statistically analysed. While perennial ryegrass tiller density declined over time, RG and HFHI spring grazing resulted in a higher perennial ryegrass tiller density than low and medium grazing frequency treatments, and forage conservation treatments. Over time, tiller density of other grass increased, with MFMI, SIL, and HAY resulting in a greater increase than HFHI and RG treatments. During the experiment, white clover growing point density declined, while broad-leaved weed tiller data were inconsistent and not analysed. In October 2001, perennial ryegrass plant frequencies ranged from 12 (HAY) to 27 (RG) plants/m2. RG resulted in a higher perennial ryegrass plant frequency than medium and low spring grazing frequencies, and forage conservation (HAY). At the end of the experiment (August 2002), perennial ryegrass frequencies ranged from 15 (HAY) to 45 (RG) plants/m2 with RG resulting in a higher perennial ryegrass plant density than all other treatments. HFHI grazing resulted in a higher plant frequency than LFLI, SIL, and HAY, and HFLI a higher plant frequency than SIL and HAY. RG and HFHI spring grazing favoured perennial ryegrass persistence as it maintained botanical composition and perennial ryegrass tiller and plant frequencies relative to low and medium spring grazing frequency or high spring grazing frequency coupled with low intensity grazing and pasture locked up for forage conservation.

Responses to the renovation of an irrigated perennial pasture in northern Victoria. 2. Botanical composition, and plant and tiller densities

2007 ◽  
Vol 47 (2) ◽  
pp. 159 ◽  
Author(s):  
A. R. Lawson ◽  
K. B. Kelly
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Tall Fescue ◽  
Active Species ◽  
Italian Ryegrass ◽  
Grass Species ◽  
Botanical Composition ◽  
Point Density ◽  
Plant Frequency ◽  
Tiller Density

A field experiment was established in northern Victoria in the autumn of 1999 to quantify the effects of renovating a 15-year-old, irrigated perennial pasture with a high paspalum content. The treatments were: (i) control, the existing pasture; (ii) oversown, the existing pasture grazed, topped and direct drilled; and (iii) resown, the existing pasture sprayed, cultivated and a new pasture sown. The grass species used in both renovation treatments were perennial ryegrass, Italian ryegrass and tall fescue. The treatments were grazed by dairy cows. The botanical composition, tiller density and plant frequency are reported in this paper. Oversowing with either perennial or Italian ryegrass increased the sown grass content by an average of 4–8% DM, and by up to 20% DM during winter and spring, but did not affect the average white clover, volunteer species or dead contents. Oversowing did not affect the sown grass or paspalum tiller densities but annual oversowing with either perennial or Italian ryegrass increased the ryegrass plant frequency and, in 2 of the 4 years, reduced the white clover growing point density. Resowing increased (P < 0.05) the content of sown grasses (by 12% DM for perennial ryegrass and by 20% DM for tall fescue) and white clover (by 8% DM) and decreased (P < 0.05) the content of volunteer species (by 18% DM) and, in years 1 and 2, dead material. The plant frequency of tall fescue increased over time (from 75 to 83% of quadrats), whereas that of perennial ryegrass declined (from 87 to 72% of quadrats). This resulted in the resown tall fescue having a lower (P < 0.05) white clover content and growing point density in years 3 and 4, and a tendency for a lower volunteer species content and tiller density in year 4, than the resown perennial ryegrass. Tall fescue is thus better able to resist the invasion of summer-active species and is less likely to require either oversowing or resowing than perennial ryegrass-based pastures. These results suggest that tall fescue should be considered as an alternative to perennial ryegrass when sowing pastures. The use of nitrogen did not improve the sown grass content, tiller density or plant frequency and will not therefore overcome problems resulting from a low ryegrass content.

scholarly journals GRAZING MANAGEMENT OF PERENNIAL RYEGRASS/ WHITE CLOVER PASTURE IN-LATE SPRING

1982 ◽  
pp. 80-84 ◽  
Author(s):  
C.J. Korte
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Accumulation Rate ◽  
Grazing Intensity ◽  
Late Spring ◽  
Grazing Management ◽  
Tiller Density ◽  
Tiller Dynamics ◽  
Clover Pasture

The patterns of herbage accumulation and the tiller dynamics of a "Grasslands Nui" perennial ryegrass dominant pasture were compared under two grazing intensity treatments in late spring. Rank stemmy herbage developed with lax grazing whereas dense leafy pasture developed with close grazing. Dead herbage and uneaten stems in rank pastures shaded photosynthetic tissue. Leafy swards had a higher herbage accumulation rate and a higher tiller density than stemmy swards. Methods of achieving leafy pasture on farms by combinations of hard grazing, forage conservation and mechanical topping are discussed briefly.

Effects of spring grazing on dryland perennial ryegrass/white clover dairy pastures. 1. Pasture accumulation rates, dry matter consumed yield, and nutritive characteristics

2006 ◽  
Vol 57 (5) ◽  
pp. 543 ◽  
Author(s):  
F. R. McKenzie ◽  
J. L. Jacobs ◽  
G. Kearney
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Dry Matter ◽  
Grazing Intensity ◽  
Water Soluble ◽  
Accumulation Rates ◽  
Leaf Stage ◽  
Rate Of Increase ◽  
The Impact ◽  
Over Time

A 3-year experiment (September 1999–August 2002) was conducted in south-western Victoria to determine the impact of spring grazing on pasture accumulation rates, dry matter (DM) consumed yield (estimate of DM yield), and pasture nutritive characteristics [metabolisable energy (ME), crude protein (CP), neutral detergent fibre (NDF), and water-soluble carbohydrates (WSC)] of a perennial ryegrass (Lolium perenne L.)–white clover (Trifolium repens L.) pasture. Spring grazing treatments, applied annually from September to November, were based on ryegrass leaf development stage with high (HF), medium (MF), and low (LF) grazing frequency being 2-, 3-, and 4-leaf stage, respectively, and post-grazing height as the grazing intensity with high (HI), medium (MI), and low (LI) grazing intensity being 3, 5, and 8 cm, respectively. Five combinations were used: HFHI, LFHI, MFMI, HFLI, and LFLI. A sixth treatment, rapid grazing (RG), maintained pasture between 1500 and 1800 kg DM/ha by grazing weekly during spring, and a seventh and eighth treatment, simulating forage conservation for early-cut silage (lock-up for 6–7 weeks; SIL) and late-cut hay (lock-up for 11–12 weeks; HAY), were also included. For the remainder of the year, all plots were grazed at the perennial ryegrass 3-leaf stage of growth, or when pasture mass had reached 2800 kg DM/ha, and grazed to a residual height of 5 cm. On average, pasture accumulation rates ranged from <5 (February–March) to 100–110 kg DM/ha.day (September–October). Overall, SIL resulted in a lower accumulation rate than all other treatments. High spring grazing frequency (including RG) treatments led to more grazing events than medium and low spring grazing frequency treatments. In Years 1, 2, and 3, DM consumed ranged from 9.7 (HAY) to 16.3 (RG), 4.2 (HAY) to 10.1 (HFHI), and 7.3 (SIL) to 10.9 t DM/ha.year (HAY), respectively. HAY resulted in a lower pasture ME content than SIL, HFHI, and LFHI spring grazing, and LFLI spring grazing resulted in a lower pasture ME content than all other treatments except HAY. HFHI grazing resulted in an increase in ME content over time, whereas the rate of increase in ME content over time was higher for LFLI spring grazing than for HAY, RG, and HFLI spring grazing. For all treatments, average pasture ME content ranged from 9.4 (January–February) to 11.4 MJ/kg DM (September). HAY resulted in a lower CP content than all treatments except LFLI grazing. RG resulted in no change in CP content over time. For all treatments, average pasture CP content ranged from a low of 11–14 (January–February) to a high of 24–28% DM (August–September). LFLI grazing resulted in a higher NDF content than HFHI, LFHI, MFMI, and HFLI grazing, while RG resulted in a lower NDF content than LFHI, MFMI, and HFLI. For all treatments, average pasture NDF content ranged from a low of 48–55 (August–September) to a high of 58–62% DM (January–February). All treatments resulted in an increase in pasture WSC content over time. The results demonstrate that frequent and intense grazing management (e.g. HFHI and RG) during spring is important in maintaining high pasture DM yields. Results also indicate positive pasture nutritive characteristic (ME, CP, and NDF) gains with more frequent spring grazing than with infrequent spring grazing. No treatment effect was observed for WSC content.

Morphology of perennial ryegrass (Lolium perenne) plants in pastures under intensive sheep grazing

1993 ◽  
Vol 120 (3) ◽  
pp. 301-310 ◽  
Author(s):  
J. L. Brock ◽  
R. H. Fletcher
Keyword(s):  
Lolium Perenne ◽  
Perennial Ryegrass ◽  
White Clover ◽  
Plant Density ◽  
Grazing Management ◽  
Stem Length ◽  
Sheep Grazing ◽  
Plant Structure ◽  
Rotational Grazing ◽  
Tiller Density

SUMMARYThe morphology of independent plants of perennial ryegrass (Lolium perenne L.) in mixed swards under intensive sheep grazing was studied at Palmerston North, New Zealand in 1988/89. Intact plants of two cultivars, ‘Grasslands Nui’ and ‘Grasslands Ariki’, were sampled from pastures under rotational grazing, set stocking, and a combination of both systems, every 2 months for 16 months, by taking turves (250 × 250 mm) and washing out the plants. Characters measured for each plant were: number of flower heads, leaves and tillers; basal stem and internode stolon length; flower head, leaf blade, leaf sheath and stolon dry weight (DW). Additional pasture data on tiller density and dispersion and herbage DW to ground level were also collected.Perennial rye grass exhibited a strong clonal growth pattern similar to that of white clover (Trifolium repens L.) but with a better balance between growth at the apex and death of old basal stem. Release of branch stolons to form new plants was regular, which maintained population stability. Formation of internode (I) stolon appeared to be a response of heavily shaded tillers for survival by elevation of the growing point to a more favourable position. The total DW of ryegrass stolon in pastures was greater than that of the companion white clover.There was little seasonal variation in number of tillers or basal (B) stem length per plant. During the reproductive period (late spring/early summer) plants were heavier and had more leaves and internode stolon than at other times of the year. Grazing management had little effect on plant structure, but plants under rotational grazing had 75% greater DW, less basal stem and reduced probability of internode stolon formation than plants under set stocking. Nui plants had heavier but fewer tillers than Ariki did, resulting in little difference in plant DW. Ariki had fewer single-tiller plants and a higher proportion of multiple-tiller (> 7) plants than Nui had. The structure of the populations was not affected by season, management or cultivar and remained stable throughout the year, with a log-normal distribution of plant size. Because of the uniformity of plant structure, plant density in pastures paralleled tiller density, averaging 1900, 3360 and 2330 plants/m2 for rotationally grazed, set stocked and combined grazing treatments respectively.In view of the strong influence that grazing management can have on ryegrass performance and persistence in pastures, the lack of response at the level of plant and population structure to grazing management suggests that some other level of organization within the ecology of the pasture is of greater importance.

scholarly journals Pastures and forages for deer growth

2003 ◽  
Vol 9 ◽  
pp. 25-40
Author(s):  
A.M. Nicol ◽  
T.N. Barry
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Red Deer ◽  
Plant Density ◽  
Red Clover ◽  
Seasonal Effects ◽  
Forage Species ◽  
Clover Pasture ◽  
Deer Grazing

Pasture is the primary feed source for NZ deer production with the greatest proportion grazed in situ. The quantity and quality of the pastures available to grazing deer varies markedly as a result of environmental factors and feed planning decisions by deer farmers. The grazing behaviour of deer responds to changes in pasture height and mass and the effect of pasture variables (height, pre -and post-grazing pasture mass and pasture allowance) on deer productivity are presented. These show that maximum levels of deer production from pasture will be achieved at a pasture height of around 8 cm (continuously stocked or post-grazing) although there is some evidence that for large genotypes, higher pasture availability is required. The relationship of liveweight gain of young deer with pasture availability shows marked seasonal effects. At the same level of pasture availability liveweight gain in spring is about twice that in winter, with autumn and summer intermediate. Increasing pasture availability cannot compensate for seasonal differences in liveweight gain. Furthermore, liveweight gain increases at a greater rate in spring than winter to increasing pasture availability, thus it is more important that appropriate pasture allowances are provided in spring than in winter. There is more variability in liveweight gain at a similar pasture availability in summer than in other seasons because of the greater variation in pasture quality in summer with the potential accumulation of seedheads and dead material. Alternative forage species are used in deer production for times of the year when quantity and quality of perennial ryegrass-based pastures limit productivity. Relative to weaner red deer grazed on perennial ryegrass/ white clover pasture, grazing on pure swards of red clover or chicory increased growth during autumn by 26-47% and during spring by 10-14%. The proportion of stags attaining target slaughter liveweight at 12 months of age increased from 75 to 94%. Pre-weaning growth during lactation was increased by approximately 20%. Red clover and chicory produce a greater proportion of their total DM during late summer and autumn than does perennial ryegrass/white clover pasture, and are therefore better aligned with deer feed requirements, particularly those of lactating hinds. Grazing on sulla in autumn and spring increased the growth of weaner deer by 33 and 10%, relative to pasture fed deer. Indoor studies showed that relative to perennial ryegrass, chicory was of higher organic matter digestibility, disintegrated more rapidly in the rumen with a low rumination time and had shorter mean retention time of material in the rumen. This explains differences in voluntary feed intake which were 56, 26 and 15% higher for deer grazing chicory than perennial ryegrass/white clover pastures during summer, autumn and spring respectively. Similar r esults have been found for the digestion of red clover versus perennial ryegrass by red deer. Plant density in stands of both chicory and red clover declines with time, with their lifetime under deer grazing being approximately 4 years. A mixture of both plants offers a food option as specialist forage for increasing deer growth and also fixing nitrogen. To ensure good persistence such forages should not be grazed in periods of prolonged wet weather. Best persistence is obtained when these are managed as specialist forages for increasing deer growth on a small area of the farm, (10- 20% total area), rather than being sown as a mixture with grasses over large areas of the farm. There is no specific comparison of deer production under different stocking systems and both continuous grazing and rotational grazing are used. Based on evidence and practices with other species, choice of stocking system has more to do with pasture/forage species, feed budgeting, pasture management and animal behaviour than with productivity. At high stocking densities (150 deer/ha), the grazing time of subordinate animals is reduced. Where possible, without inducing undue stress (e.g. at weaning), young deer should be grouped for grazing by liveweight. Deer production systems have a seasonal pattern of energy demand that does not match that of pasture growth in most NZ environments. This calls for manipulation of the feed demand by integration of livestock systems and/ or modification of the feed supply through conservation and supplementation. The most commonly used supplements are pasture and lucerne silage/baleage and grain. The quality (ME/kg DM) has a significant impact on the resulting liveweight gain.

Persistence of perennial ryegrass, tall fescue and cocksfoot following annual sowings: influence of grass species, ryegrass cultivar and pasture age on yield, composition and density

2021 ◽  
Vol 17 ◽  
Author(s):  
Tom Maxwell ◽  
Grant Edwards ◽  
Katherine Tozer ◽  
Gerald Cosgrove
Keyword(s):  
Perennial Ryegrass ◽  
Tall Fescue ◽  
Grass Species ◽  
Botanical Composition ◽  
Release Date ◽  
Confounding Effect ◽  
Pasture Grass ◽  
Age Cohort ◽  
Tiller Density ◽  
Pasture Age

Persistence is an important component of perennial pasture-grass productivity. Defining traits that affect persistence is essential for improving pasture longevity through plant breeding and for identifying persistence traits that should be included in cultivar ranking indices. Compared with conventional longitudinal studies, where a single sowing is monitored over time, repeated annual sowings allow the effects on persistence of sowing year and the ensuing interactions between environment and age of pasture to be identified. An experiment was commenced in 2015 under sheep grazing in Canterbury and in 2016 under cattle grazing in Waikato, where eight cultivars of perennial ryegrass representing different ploidy, flowering date, and cultivar age (release date), and one cultivar each of tall fescue and cocksfoot were sown in four randomised complete blocks in autumn each year. This paper reports interim data on spring and autumn pasture yield, composition, and density of 3-year-old, 2-year-old and 1-year-old pastures exposed to the same environmental conditions within the same, single year. There were significant effects on yield, botanical composition, basal cover and tiller density due to cultivar, pasture age, and their interaction. When the confounding effect of year-to-year variation was removed by comparing each age cohort in the same year, the underlying differences among grass species and cultivars, and ages of pasture, is starting to reveal the nature of this influence on pasture persistence.

scholarly journals Nitrate leaching and N2-fixation in grasslands of different composition, age and management

2004 ◽  
Vol 142 (2) ◽  
pp. 141-151 ◽  
Author(s):  
J. ERIKSEN ◽  
F. P. VINTHER ◽  
K. SØEGAARD
Keyword(s):  
Perennial Ryegrass ◽  
Nitrate Leaching ◽  
Dry Matter ◽  
Grazing Intensity ◽  
Dry Matter Production ◽  
Leaching Losses ◽  
N Removal ◽  
Matter Production ◽  
Over Time

Grass-legume associations may offer a way of improving the N efficiency of dairy farming, but may also have an adverse impact on the environment by increasing leaching losses. Nitrate leaching from four cropping sequences with different grassland frequency and management (long-term grazed, long-term cut, cereals followed by 1 and 2-year grazed leys) were investigated on a loamy sand in central Jutland for both unfertilized grass-clover (perennial ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.)) and fertilized perennial ryegrass (300 kg N/ha) swards during 1997–2002. Furthermore, 1 year (2001) of N2 fixation in 1-, 2- and 8-year-old grass-clover pastures was determined. Nitrate leaching from grazed unfertilized grass-clover was always considerably lower than from grazed fertilized ryegrass. The effect of grassland age on nitrate leaching was insignificant in grass-clover but clear in grazed ryegrass, where levels increased dramatically with sward age. In production years 6–8, leaching from grass-clover was only 9–13% of the comparable losses from ryegrass. Under the cutting regime grass-clover showed a significant reduction in both yield and N-removal with increasing sward age, whereas for ryegrass these figures did not show any decreasing trend. N2 fixation was lower in 8-year-old swards compared with fully established 2-year-old swards as a consequence of lower dry matter production, lower clover content and a lower proportion of clover-N derived from the atmosphere. The results from the present study indicate that the higher leaching losses observed in fertilized grass compared with unfertilized grass-clover systems were caused by (1) a reduction in N2-fixation in grass-clover over time and (2) a reduction in dry matter production in grass-clover over time, lowering the grazing intensity and the recycling of grassland N via animal excreta.

scholarly journals Milksolids production from different combinations of perennial ryegrass and white clover cultivars: I Trial design and pasture performance

2001 ◽  
pp. 91-96 ◽  
Author(s):  
J.P.J. Eerens ◽  
J.R. Crush ◽  
S.L. Woodward ◽  
K.A. Macdonald ◽  
W.A. Carter
Keyword(s):  
Perennial Ryegrass ◽  
White Clover ◽  
Block Design ◽  
Late Summer ◽  
First Year ◽  
Endophyte Infection ◽  
Commercial Sources ◽  
Tiller Density ◽  
Clover Content

A whole-farm systems comparison of combinations of perennial ryegrass and white clover cultivars rotationally grazed by dairy cows over two complete seasons evaluated improvements in perennial ryegrass and white clover cultivars resulting from plant breeding efforts. There were four treatments comprised of two ryegrass mixtures and two clover mixtures in a 2 x 2 factorial design, each replicated three times in a randomised block design giving 12, self-contained 4-ha farmlets each stocked at three multiparous Friesian cows/ ha. All pastures were sown in April 1998, using seed obtained through commercial sources, with a high endophyte (>70% endophyte infection) specification for the ryegrass cultivars. A grow out test, carried out after sowing, showed that two of the ryegrass cultivars used in the mix of older cultivars (80R) had less than 70% endophyte infection (Ellett 50%, Nui 62%, Yatsyn 94%) resulting in an average endophyte infection of 69% for that mix. The mix of newer ryegrass (98R) cultivars had an average endophyte infection of 92% (Aries HD 91%, Bronsyn 98%, Samson 87%). While seedling densities (ryegrass and clover) were similar for all mixtures at the start, from late summer of the first year onward, tiller densities were around 30% lower (due to predation of endophyte-free plants and tillers by the Argentine stem weevil) in the 80R treatment. The lower tiller density opened up the sward at an opportune time for clover expansion, which the newer clover cultivars (98C) Sustain and Challenge converted into a higher clover production than from the older clover cultivars (60C) Huia and Pitau. The 80R treatment had a greater spring surplus requiring more conservation than the 98R treatment, which had a more even growth distribution over the year. Differences in endophyte infection levels had a major impact on pasture composition, especially clover content; reducing the endophyte level of seed sown from 90% to 70% may create an opportunity to increase the clover content and quality of young pastures in the Waikato. Keywords: cultivars, dairying, endophyte, perennial ryegrass, tiller density, white clover

scholarly journals Liveweight changes in lambs grazing six perennial ryegrass cultivars

1999 ◽  
pp. 31-35
Author(s):  
C.T. Westwood ◽  
M.G. Norriss
Keyword(s):  
New Zealand ◽  
Perennial Ryegrass ◽  
White Clover ◽  
Dry Matter ◽  
Moisture Stress ◽  
Botanical Composition ◽  
Independent Research ◽  
Ewe Lambs ◽  
Research Organisation ◽  
Clover Content

Liveweight changes were measured for lambs grazing six high endophyte perennial ryegrasses, in a grazing experiment run by an independent research organisation in Canterbury, New Zealand. Ryegrass cultivars were sown under code in a binary mix with white clover in February 1997. Plots were strategically irrigated to avoid moisture stress, and stocked at approximately 27 Coopworth ewe lambs per ha in May 1997. Common pasture residual mass was maintained across cultivars by strategic addition of extra lambs, with extra grazing days recorded for each replicate. Lamb liveweight gains and botanical composition of replicates were assessed quarterly. Lamb liveweight gains differed significantly between treatments in Years 1 and 2 of this ongoing 3 year study. Lambs grazing 'Quartet' tetraploid perennial ryegrass gained, on average, 37.4 kg and 36.1 kg liveweight during Years 1 and 2 respectively, and together with 'Aries HD' (35.0 and 35.9 kg) produced significantly greater liveweight gain compared with 'Grasslands Nui' (22.0 and 23.7 kg) and 'Bronsyn' (22.5 and 24.1 kg), LSD0.05 = 6.0 and 7.4. Lambs grazing 'Embassy' gained 31.6 kg and 28.7 kg, and 'Vedette' 29.8 kg and 28.0 kg. Extra grazing days expressed as a percentage of base grazing days were between 3.8 and 6.7% across cultivars for Year 1 and between 2.0 and 6.5% across cultivars for Year 2. This study demonstrated significant differences in animal productivity between perennial ryegrass cultivars that produce comparable yields of dry matter. Differences may reflect variation in forage quality, endophyte toxins, clover content in the sward or other unidentified cultivar characteristics. Keywords: digestibility, endophyte, lamb, liveweight, perennial ryegrass, tetraploid

Sign in / Sign up

Export Citation Format

Share Document