SGS Animal Production Theme: effect of grazing system on animal productivity and sustainability across southern Australia

2003 ◽  
Vol 43 (8) ◽  
pp. 977 ◽  
Author(s):  
J. F. Graham ◽  
B. R. Cullen ◽  
G. M. Lodge ◽  
M. H. Andrew ◽  
B. P. Christy ◽  
...  

The effects of various grazing management systems on sown, naturalised, and native pastures were studied at 6 different locations in the temperate high rainfall zone (HRZ, >600 mm rainfall/year) of southern Australia, as part of the Sustainable Grazing Systems (SGS) Program. The treatments examined had different pasture species and fertiliser management, with grazing method ranging from set stocking (continuous grazing) to rotation with rests based on pre- and post-grazing herbage mass or season and plant phenology. Sites were located at: Albany, Western Australia; Manilla, Barraba, Nundle, New South Wales; (grazed by wethers); and Carcoar, New South Wales; Maindample, Ruffy, north-east Victoria; Vasey, western Victoria; (grazed by ewes and lambs).Grazing method significantly (P<0.001) influenced stocking rate (expressed as dry sheep equivalents (DSE)/ha), but effects were not consistent across sites. At Vasey the stocking rate of the rotation treatments ranged from 5 to 23% higher than the set stocked treatments depending upon year. For all sites, significant factors (P<0.001) affecting stocking rate were soil Olsen P, soil pH, grazing management (resting), legume percent, and an index of growing season effectiveness. Although total annual rainfall had a significant effect (P<0.002) in an initial analysis, its influence became non-significant (P>0.05), when a growing season index (P<0.001) was used. Non-significant (P>0.05) factors included solar radiation, annual average temperature, fertiliser applied in the current year, and average annual perennial and broadleaf percent composition. The implications of these data for productivity and sustainability (as assessed by perenniality and water use) were encouraging. Generally, there were positive relationships between increased stocking rate and the probability of achieving a zero mm soil water surplus in winter, and between increased productivity and the proportion of perennial grass species where extremes of treatments were compared at each site. The results indicate that stocking rate can be increased without jeopardising sustainability, that grazing management can bring about more sustainable pastures, that there is scope to increase productivity particularly through increasing soil fertility, and growing season length can be used to predict potential carrying capacity. These are positive outcomes that graziers in the HRZ of southern Australia can use to enhance productivity (thus profitability) and sustainability.


1994 ◽  
Vol 17 (1) ◽  
pp. 19
Author(s):  
J. Barker ◽  
D. Lunney ◽  
T. Bubela

Mammal surveys were carried out on the Carrai Plateau and Richmond Range in north-east New South Wales between March 1988 and November 1989. The emphasis was placed on rainforest mammals, following the recognition by Adam ( 1987) that the species lists of mammals in the state&apos;s rainforests were incomplete and that more research was needed. The mammals were surveyed primarily by analysis of prey remains in Dog and Fox scats, collected from roads throughout the forests, and from bat trapping. The bat fauna at both the Carrai Plateau and Richmond Range is rich (1 0 species and nine species respectively, including the rare Golden-tipped Bat, Kerivoula papuensis, in the Richmond Range). Scat analysis revealed the presence of 24 native species on the Carrai Plateau, and on the Richmond Range there were 17 species, including high numbers of two pademelon species. Feral prey species are almost completely absent, although the Fox is an established predator in both areas. A sharp division was identified between the mammal faunas of closed and open forests. Differences were found also between the mammal fauna composition of the two rainforest sites, and with those of nearby eucalypt forests. The mammal fauna of New South Wales rainforests is distinct from open forests and future mammal surveys are needed to ensure an adequate level of knowledge to identify and conserve these areas.



1999 ◽  
Vol 47 (4) ◽  
pp. 563 ◽  
Author(s):  
Tamara R. Read ◽  
Sean M. Bellairs

The germination responses to plant-derived smoke of seeds of 20 native grass species from New South Wales, Australia, were tested under laboratory conditions. The species belonged to 14 genera including Bothriochloa, Chloris, Cymbopogon, Danthonia, Dichanthium, Digitaria, Eragrostis, Eriochloa, Microlaena, Panicum, Paspalidium, Poa, Stipa and Themeda. The interaction between smoke and husk-imposed dormancy was examined by removing the floral structures surrounding the seeds, when sufficient seeds were available. Smoke was shown to be an important environmental stimulus for breaking the dormancy of native grasses; however, the response differed considerably between different genera and between species of the same genus. For almost half of the species, smoke significantly increased the germination percentage. Panicum decompositum showed the greatest response, with germination increasing from 7.7 to 63.1% when smoke was applied. Panicum effusum had no germination in the absence of smoke, but 16.7% germination when smoke was applied. Stipa scabra subsp. scabra had germination significantly reduced by smoke from 30.2 to 19.9%. Five species had their germination rate, but not the final germination percentage, affected by smoke, and a third of the species were unaffected by smoke. For five of the species, Chloris ventricosa, Dichanthium sericeum, Panicum decompositum, Poa labillardieri and Stipa scabra subsp. falcata, this is the first report of a smoke-stimulated germination response. For those species with germination promoted by smoke, retention of the covering structures did not prevent smoke stimulation of germination. Sowing smoke-treated husked seeds is likely to be preferable as it would still promote greater germination, whereas dehusking seeds can result in the seeds being more susceptible to desiccation and fungal attack in the field. It is suggested that other grassland communities that respond to pyric conditions may also contain species that respond to smoke.



1974 ◽  
Vol 14 (67) ◽  
pp. 231 ◽  
Author(s):  
OR Southwood ◽  
F Mengersen ◽  
PJ Milham

The effect of three rates of nitrogen (22.4, 44.8 and 89.6 kgNha-1 as anhydrous ammonia) and three seeding rates (67.3, 100.9, and 134.5 kg ha-1) on forage and grain production of two oat cultivars and on herbage nitrate-nitrogen concentration, was assessed at three sites in the southern New South Wales wheat belt. When oats were sown after two or three consecutive wheat crops nitrogen at 22.4 kg ha-1 was optimal for both forage and grain production. Herbage growth was best at the highest seeding rate (134.5 kg ha-1) but grain production was not influenced by seeding rate. Herbage growth of the oat cultivars Cooba and Coolabah was similar, but grain yields were higher from the latter. Herbage nitrate nitrogen increased linearly with nitrogen fertilizer application, levels that could be toxic to animals occurring in June. Cautious grazing management may be required during this period.



1988 ◽  
Vol 28 (5) ◽  
pp. 561 ◽  
Author(s):  
HL Davies ◽  
E Devaud

A March-April joining of Merino ewes was compared with a June-July joining in central New South Wales at a low stocking rate on subterranean clover based pastures over 3 years. In all years, ewes joined in June were heavier (P < 0.05) than ewes joined in March (55 v. 52 kg). Liveweights at the start of lambing and liveweight change from joining to lambing were also high and favoured the later lambing group. The proportion of ewes lambing (97% March v. 93% June) and proportion of ewes twinning (29% March v. 20% June) were not significantly different between the 2 groups, but consistently favoured the March-April joining. Perinatal mortality was low (9.4% March v. 7.1% June) and not significantly different between the 2 groups, but was consistently lower in the June joined group. Number of lambs weaned per 100 ewes joined was also not significantly different, but was higher each year in the March joined group (1 13% March v. 105% June). The growth rate of the lambs (both singles [24% greater, 248 v. 200 g/day] and twins [37% greater, 2 13 v. 155 g/day]) was consistently in favour of March joined ewes. Mean greasy fleece weights of the ewes were not significantly different between the 2 groups, but were in favour of the late joined group (4.83 v. 4.50 kg). Time of joining significantly affected liveweights and greasy and clean fleece weights of the progeny at the shearing in the year following their birth in favour of March joining. These data suggest that, despite a nutritional advantage to the ewes in late pregnancy and milder weather at lambing with a June-July joining, a March- April joining is the preferred option on the Central Tablelands of New South Wales.



1995 ◽  
Vol 35 (1) ◽  
pp. 93 ◽  
Author(s):  
RD FitzGerald ◽  
ML Curll ◽  
EW Heap

Thirty varieties of wheat originating from Australia, UK, USA, Ukraine, and France were evaluated over 3 years as dual-purpose wheats for the high rainfall environment of the Northern Tablelands of New South Wales (mean annual rainfall 851 mm). Mean grain yields (1.9-4.3 t/ha) compared favourably with record yields in the traditional Australian wheatbelt, but were much poorer than average yields of 6.5 t/ha reported for UK crops. A 6-week delay in sowing time halved grain yield in 1983; cutting in spring reduced yield by 40% in 1986. Grazing during winter did not significantly reduce yields. Results indicate that the development of wheat varieties adapted to the higher rainfall tablelands and suited to Australian marketing requirements might help to provide a useful alternative enterprise for tableland livestock producers.



1971 ◽  
Vol 19 (2) ◽  
pp. 177 ◽  
Author(s):  
MMH Wallace ◽  
JA Mahon

The lucerne flea, S. viridis, is restricted to the southern parts of Australia and, apart from a few isolated occurrences in eastern New South Wales, occurs only in areas with an essentially Mediterranean-type climate. The northern inland limit to its distribution agrees closely with the 250-mm isohyet for the growing season of May-October inclusive. The eastern limit to distribution in New South Wales and Victoria agrees with a December-March isohyet of 225 mm. Areas east of this line receive predominantly summer rainfall, and the pastures contain a high proportion of perennial plants which probably do not provide the nutritional stimulus for the development of aestivating diapause eggs in S. viridis essential for oversummering. The predatory mite B. lapidaria requires slightly moister conditions than S. viridis and the limit of its inland distribution agrees reasonably well with the 260-mm isohyet for the May-October period. Low temperatures (mean maximum < 17.5'C) also seem necessary during this period. The eastern distribution limits in Victoria are similar to those of S. viridis.



1989 ◽  
Vol 11 (2) ◽  
pp. 61 ◽  
Author(s):  
PJS Fleming ◽  
TJ Korn

A monthly survey involving officers from eastern New South Wales Pastures Protection Boards was conducted over four years from 1982 to 1985. Information was collected on the number and type of livestock attacked within each board district, sightings of wild dogs, the number of wild dogs kiied, the method by which they were kiied and the locations at which the observations occurred. A total of 25,644 livestock animals were reported killed or wounded from four regions; the North-East Coastal Region, the North-East Tablelands Region, the Central-East Region and South-East Region. Sheep were the most commonly attacked domestic animals followed by cattle and goats. Regional differences were apparent in the type of livestock killed and seasonal patterns of predation were evident. We recommend that annual control programmes be brought forward from June/July to late April in order to precede predation peaks.



2006 ◽  
Vol 46 (4) ◽  
pp. 495 ◽  
Author(s):  
R. E. Jones ◽  
P. M. Dowling ◽  
D. L. Michalk ◽  
W. McG. King

There have been significant declines in the perennial grass (PG) content in native and sown pastures across temperate Australia. Not only has this reduced agricultural productivity, it has contributed to more serious degradation, such as loss of soil and biodiversity, decreasing water quality, and dryland salinity caused by rising watertables. Results from the Sustainable Grazing Systems Key Program (SGS) research undertaken at Carcoar on the Central Tablelands of New South Wales were reported by Michalk et al. (2003). This research indicated that grazing management tactics can be used to manipulate pasture composition, thereby changing animal production and water-use patterns. The main grazing tactic investigated was termed a summer grazing rest, where resting was imposed in late spring if PG composition was <50%. Reported in this present paper is an economic framework for valuing the long-term benefits of grazing management tactics. The framework involves the development of a bioeconomic modelling system that links a dynamic programming model with biophysical models for water and environmental processes, soil fertility, pasture growth, livestock energy requirements and the change in pasture species composition. The study concludes that long-term economic returns are improved by strategies, e.g. a summer rest, that lead to an increase in PG composition over time. The study also determined that environmental factors, such as deep drainage, runoff and soil loss, are reduced as perenniality is increased.



2004 ◽  
Vol 18 (3) ◽  
pp. 291 ◽  
Author(s):  
Kerrie A. Davies ◽  
Robin M. Giblin-Davis

Nematodes of the genus Fergusobia Currie (Tylenchida : Neotylenchidae) and flies of the genus Fergusonina Malloch (Diptera : Fergusoninidae) together form the only known mutualistic association between insects and nematodes that induces galls in young meristematic tissues in Myrtaceae. Six new species of Fergusobia are described (F. quinquenerviae, sp. nov., F. cajuputiae, sp. nov., F. dealbatae, sp. nov., F. leucadendrae, sp. nov., F.�nervosae, sp. nov., and F. viridiflorae, sp. nov.) and partial descriptions are presented for a further two species. Together, these taxa form a putative monophyletic group, apparently restricted to species of Melaleuca in the broad-leaved M. leucadendra-complex, from coastal Queensland and north-east New South Wales, Australia. Each species of nematode has a mutualistic association with a particular species of Fergusonina fly and (with one exception) each association is apparently restricted to one particular species of Melaleuca.



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