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I R Johnson - One of the best experts on this subject based on the ideXlab platform.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60-70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70-$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:Abstract The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60–70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70–$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.
D F Chapman - One of the best experts on this subject based on the ideXlab platform.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60-70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70-$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:Abstract The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60–70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70–$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.
C A M De Klein - One of the best experts on this subject based on the ideXlab platform.
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the effectiveness of the nitrification inhibitor dicyandiamide dcd in reducing nitrate leaching and nitrous oxide emissions from a grazed winter Forage Crop in southern new zealand
Agriculture Ecosystems & Environment, 2013Co-Authors: R M Monaghan, L C Smith, C A M De KleinAbstract:Abstract The over-wintering of dairy cows on Forage brassica Crops is a common practice on many dairy farms in southern New Zealand. Although this is seen as a cost-effective strategy for providing required amounts of winter feed, little is known of the environmental footprint that is generated from these grazed Forage Crops. Here we report measured N leaching and nitrous oxide losses from soil used for winter kale Cropping where experimental plots were managed to simulate dairy cow grazing. The effectiveness of the nitrification inhibitor dicyandiamide (DCD) in reducing these N losses was also measured. Measured nitrate leaching losses from the winter Forage Crops averaged 52 kg N ha −1 yr −1 over the 3 measurement years. Nitrous oxide emissions represented an equivalent paddock loss between June and November of 3.6 and 1.5 kg N ha −1 yr −1 for 2006 and 2008, respectively. Single mid-winter applications of DCD, equivalent to 10 kg active ingredient (a.i.) ha −1 following simulated grazing each year, had only small and non-significant effects on reducing N leaching losses from the Forage Crop, but did significantly reduce N 2 O emissions by 25% during the 2006 winter and spring months and appeared to be most effective under moist soil conditions. An estimated 20–40 kg N ha −1 was estimated to be conserved due to DCD application to the grazed Forage Crop, which contributed to increased biomass yields in pasture that was sown following the Forage Crop. A simple cost–benefit analysis suggests that the use of DCD on winter Forage Crops may deliver a financial benefit due to the increased growth observed for pasture that is re-established the following spring.
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the effectiveness of dicyandiamide in reducing nitrous oxide emissions from a cattle grazed winter Forage Crop in southland new zealand
Animal Production Science, 2008Co-Authors: L C Smith, R M Monaghan, C A M De Klein, W D CattoAbstract:A study was conducted in Southland, New Zealand to: (i) measure nitrous oxide (N2O) emissions and nitrate (NO3–-N) leaching losses from a cattle-grazed, winter Forage Crop; and (ii) quantify the effect of dicyandiamide (DCD) in reducing these losses. Drainage losses were measured for 12 months (December 2005–November 2006) from a December-sown kale Crop using 12 hydrologically isolated drainage plots at the Woodlands Research Station. N2O emissions were measured for 6 months (June–November) following simulated grazing of the Crop in mid-June. N2O emissions from the bare ground following grazing of the Crop amounted to 3.6 kg nitrogen (N)/ha for the winter–spring period. This figure is higher than that measured for pasture on the same soil type over a similar period. DCD application significantly reduced N2O emissions for the whole Crop area by 25% over this period and reduced the N2O emission factor for urine by 54%. DCD application increased the length of time mineral N (0–10 cm soil depth) was maintained in the ammonium form and significantly reduced soil NO3–-N levels for 6 weeks following the simulated grazing. Annual NO3–-N losses in drainage under this winter Forage Crop were relatively high at 79 kg N/ha.year, with the majority of this (67%) being lost over the wet summer months (December–January rainfall 434 mm or 200% of normal) during Crop growth. The application of DCD following the grazing resulted in a 47% decrease in NO3–-N leached over the winter–spring period (26 kg N/ha v. 14 kg N/ha) with this equating to a 29% decrease over the full 12-month measurement period. This study suggested that winter Forage Crops are major contributors to N losses from livestock farming systems in Southland and that DCD application following the grazing of such Crops by cattle can significantly reduce N2O emissions and leaching N losses.
Quanwen Dou - One of the best experts on this subject based on the ideXlab platform.
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Molecular karyotyping of Siberian wild rye (Elymus sibiricus L.) with oligonucleotide fluorescence in situ hybridization (FISH) probes.
PloS one, 2020Co-Authors: Jihong Xie, Ruijuan Liu, Yan Zhao, Quanwen DouAbstract:Siberian wild rye (Elymus sibiricus L.), an allotetraploid species, is a potentially high-quality perennial Forage Crop native to temperate regions. We used fluorescently conjugated oligonucleotides, representing ten repetitive sequences, including 6 microsatellite repeats, two satellite repeats, and two ribosomal DNAs, to characterize E. sibiricus chromosomes, using sequential fluorescence in situ hybridization and genomic in situ hybridization assays. Our results showed that microsatellite repeats (AAG)10 or (AGG)10, satellite repeats pAs1 and pSc119.2, and ribosomal 5S rDNA and 45S rDNA are specific markers for unique chromosomes. A referable karyotype ideogram was suggested, by further polymorphism screening, across different E. sibiricus cultivars with a probe mixture of (AAG)10, Oligo-pAs1, and Oligo-pSc119.2. Chromosomal polymorphisms vary between different genomes and between different individual chromosomes. In particular, two distinct forms of chromosome E in H genome were identified in intra- and inter-populations. Here, the significance of these results, for E. sibiricus genome research and breeding, and novel approaches to improve fluorescence in situ hybridization-based karyotyping are discussed.
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Isolation and characterization of chromosomal markers in Poa pratensis.
Molecular cytogenetics, 2017Co-Authors: Yanyan Zhao, Ruijuan Liu, Quanwen DouAbstract:Background Poa pratensis L. is a turf grass and Forage Crop used worldwide. Being a facultative apomictic species, P. pratensis has a highly variable chromosome number. Chromosomal markers constitute a powerful tool for chromosome identification and for various aspects of genomic research. However, currently, no chromosomal markers are available for P. pratensis.
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development and characterization of 53 polymorphic genomic ssr markers in siberian wildrye elymus sibiricus l
Conservation Genetics Resources, 2014Co-Authors: Yunting Lei, Yanyan Zhao, Quanwen DouAbstract:Siberian wildrye, Elymus sibiricus L., is an important perennial Forage Crop in temperate regions of the world, especially in the Qinghai–Tibet plateau. However, it is now threatened by climate warming, excessive grazing, and damage to its natural habitat. A total of 53 polymorphic genomic-SSR markers were isolated and characterized in E. sibiricus. The number of alleles for these markers in 11 individuals varied from 2 to 5, with an average of 3.09 alleles per locus. Segregation analysis in an F2 population revealed that the tested genomic-SSR markers had a co-dominant nature and Mendelian inheritance. Cross-species amplification tests showed that about half of the total E. sibiricus genomic-SSR markers could be effectively amplified in E. nutans. These SSR markers are the first characterized in E. sibiricus and will be useful for investigating genetic diversity and molecular-assisted breeding.
S N Kenny - One of the best experts on this subject based on the ideXlab platform.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60-70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70-$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.
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pasture and Forage Crop systems for non irrigated dairy farms in southern australia 1 physical production and economic performance
Agricultural Systems, 2008Co-Authors: D F Chapman, S N Kenny, D Beca, I R JohnsonAbstract:Abstract The dairy industry in southern Australia relies on perennial ryegrass pasture to supply 60–70% of the diet of lactating cows. Improvements in the amount and quality of home-grown Forage used for dairy cow feeding are critical for further productivity gains in the industry. A modeling approach was used to estimate the effects of changing the Forage system on farm business profit. Base models (using 100% of farm area in perennial ryegrass pasture) were constructed for above-average (Top 40%) and high performing (Top 10%) farm types typical of two locations: Terang in southwest Victoria and Ellinbank in Gippsland, eastern Victoria. These models were then re-simulated using different Forage base options such as: oversowing annual ryegrass, winter Crops (annual ryegrass monoculture, winter cereal grown for whole Crop silage), summer Crops (grazing brassicas, maize), combinations of these (double Cropping), or summer shoulder pasture (notionally based on tall fescue) on between 10% and 100% of farm area. Estimated total home-grown Forage consumption ranged between 6.7 and 10.2 t DM/ha/year for Terang and 7.8 and 11.9 t DM/ha/year for Ellinbank. Within farm types at Terang, the amount of home-grown Forage consumed explained between 30% and 45% of the variation in operating profit. The models predicted that profit improvements of $70–$100 per hectare per additional tonne of home-grown Forage consumed are possible from changing the Forage base. Oversowing annual ryegrass led to greater Forage supply, but only at times when pasture availability was largely adequate to meet current herd requirements therefore additional feed was not used as cost-effectively as other options. By contrast, the summer shoulder pasture type shifted the seasonal distribution of Forage supply further into summer compared to perennial ryegrass, and led to higher amounts of pasture in the diet and greater profitability. Double Cropping systems also appeared capable of increasing operating profit and total home-grown Forage consumption. Increasing home-grown Forage consumption and profit by using some of the alternative pastures and Forage Crops investigated here requires better information on Crop/pasture agronomy, management and feeding, and greater decision-making and management input compared to current systems.