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Full-Text Articles in Physical Sciences and Mathematics
Deforestation For Pasture Development – Has It Been Worth It?, W. H. Burrows
Deforestation For Pasture Development – Has It Been Worth It?, W. H. Burrows
IGC Proceedings (1993-2023)
Differing scenarios leading to deforestation for pasture development in savanna (woodland) and closed forest communities in the tropics – sub-tropics are compared and contrasted. Australian and Brazilian examples are highlighted. No simple answer is given to the question of whether deforestation for pasture development has been worth it, since both commercial and non-commercial values have equal validity and need to be taken into account. These issues are addressed in the context of land assigned by governments for agricultural purposes. It is concluded that technology and ecological understanding are now available to maintain sustainable production from converted forest systems. However emphasis …
Determining Pasture Biodiversity With Nirs, K. J. Moore, D. J. Barker
Determining Pasture Biodiversity With Nirs, K. J. Moore, D. J. Barker
IGC Proceedings (1993-2023)
Research was conducted to assess the potential of using near infrared reflectance spectroscopy (NIRS) to determine botanical composition and measures of species diversity in pasture samples. Samples were collected from six hill country (Ballantrae) and two lowland (Aorangi) pastures in New Zealand. Samples were collected in summer (March) and Autumn (May) and subsamples were dissected to determine botanical composition and species diversity. Measures of diversity included species richness, Shannon’s index, and Simpson’s index. Reflectance data were collected from a second subsample that had been dried and finely ground. Calibrations were developed using modified partial least squares. Acceptable calibration equations were …
Integration Of Cattle And Improved Pastures Under Coconuts In Southern Luzon, Philippines, F. A. Moog, H. E. Diesta, A. G. Deocareza
Integration Of Cattle And Improved Pastures Under Coconuts In Southern Luzon, Philippines, F. A. Moog, H. E. Diesta, A. G. Deocareza
IGC Proceedings (1993-2023)
Results of two studies involving 1) grazing of Signalgrass (Brachiaria decumbens) pastures at different stocking and 2) cut-and-carry forages in smallholder farms for cattle under coconuts are presented. Grazing at 3 AU/ha and 2 AU/ha gave significantly higher LWG/ha (P 0.05) over 1 AU/ha but highest financial return was obtained from 2 AU/ha. Productivity of cattle on cut-and-carry forages in small farms varies among farmers with better animal performance directly related to quantity and quality of feeds offered and industriousness of individual farmers. Both studies showed the benefits derived from integration of cattle with improved pastures under coconuts.
Feeding Of Conserved Forage - Implications To Grassland Management And Production, C. W. Holmes, P. N. P. Matthews
Feeding Of Conserved Forage - Implications To Grassland Management And Production, C. W. Holmes, P. N. P. Matthews
IGC Proceedings (1993-2023)
This review will focus on the use of conserved forages in pastoral dairy farm systems; especially on their conservation as an aid to good grazing management during periods of rapid pasture growth, and on their consumption as an aid to good feeding management and grazing management during periods of slow pasture growth. Conservation of pasture, in order to move it from one time to another later time, always involves “costs”, either financial expenditure or physical losses (of dry matter/quality) or both, which must be evaluated in the whole system.
Most of the data is drawn from New Zealand and Australia, …
Supplementation Of Lactating Cows Grazing Stargrass (Cynodon Nlenfuensis Var. Nlenfuensis) With Conjugated Linoleic Acid: Effects On Persistency And Estimated Net Energy Balance, S. R. Medeiros, D. E. Oliveira, L. J. M. Aroeira, M. Mcguire, D. P. D. Lanna
Supplementation Of Lactating Cows Grazing Stargrass (Cynodon Nlenfuensis Var. Nlenfuensis) With Conjugated Linoleic Acid: Effects On Persistency And Estimated Net Energy Balance, S. R. Medeiros, D. E. Oliveira, L. J. M. Aroeira, M. Mcguire, D. P. D. Lanna
IGC Proceedings (1993-2023)
Thirty crossbread cows grazed stargrass (Cynodon nlenfuensis var. nlenfuensis) receiving 4kg/d of a supplement formulated to provide 115% of metabolizable protein requirements from the 4th to the 11th week of lactation. The cows received either 150g/head/day of Megalac (Control) or 150g/head/day of a Ca-protected conjugated linoleic acid (CLA, Church & Dwight). Residual effects of treatment were evaluated in weeks 12th and 13th. Milk production increased in CLA treated cows (P< 0.05). CLA decreased milk fat content (P< 0.0001) and yield (P< 0.01). Protected CLA increased protein content (P< 0.01) and yield (P< 0.01). The CLA residual effect on milk fat ends within one week after withdrawal but the benefits on milk yield and total solids production continued, due to the increased persistency. The estimated energy balance and intake were not greatly affected by treatment, as treated cows had higher milk volume and had higher protein productions.
Urine Calcium But Not Plasma Calcium Or Urine Hydroxyproline Is Increased By A Systemic Acidosis In The Dairy Cow, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver
Urine Calcium But Not Plasma Calcium Or Urine Hydroxyproline Is Increased By A Systemic Acidosis In The Dairy Cow, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver
IGC Proceedings (1993-2023)
Eight non-lactating, pregnant Holstein-Friesian cows were allocated to two treatments and individually offered diets differing in dietary cation-anion difference. Decreasing the dietary cation-anion difference reduced the urine pH within hours of anionic salt supplementation. Plasma calcium concentration was unaffected by dietary cation-anion difference but urine calcium concentration was significantly increased within 10 days of including anionic salts in the diet. Faecal calcium concentration was significantly reduced, indicating increased calcium absorption. Dietary calcium concentration or dietary cationanion difference did not significantly affect urinary hydroxyproline.
Dry Matter Intake Of Periparturient Cows On A Fresh Pasture/Pasture-Hay Diet, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver
Dry Matter Intake Of Periparturient Cows On A Fresh Pasture/Pasture-Hay Diet, J. R. Roche, Dawn E. Dalley, F. O’Mara, E. S. Kolver
IGC Proceedings (1993-2023)
Reports of the depression in dry matter intake in the periparturient period have been inconsistent and little dry matter intake data is available for an all-forage diet prior to calving. Data to examine intake depression prior to calving was obtained from two experiments. In experiment 1, sixteen non-lactating, periparturient cows ate 1.3% of pre-calving body weight of grass-hay and freshly cut grass for two weeks pre-calving (restricted). Experiment 2 comprised thiry-six cows that ate 1.6% of pre-calving body weight of grass-hay and freshly cut grass for the final two weeks of pregnancy (ad libitum). Individual dry matter intakes …
"Estimation Of The Primary Net Production Above Ground Through Remote Sensing In A Pastoral System Of The Colombian Altillanura.", R. A. Díaz, M. Álvarez, O. Pérez, J. Bernal, M. Arango
"Estimation Of The Primary Net Production Above Ground Through Remote Sensing In A Pastoral System Of The Colombian Altillanura.", R. A. Díaz, M. Álvarez, O. Pérez, J. Bernal, M. Arango
IGC Proceedings (1993-2023)
The primary net production above ground (ANPP) represents the main forage resource that supports the bovine production systems and its valuation is essential to help in the decision making on the management of the pastures. The ANPP has been estimated by periodic biomass courtesy, but with the use of the remote sensor integrated into the efficiency model formulated by Monteih (1972), it has been possible to estimate this biophysical parameter more efficiently at different scales and at low cost. The objective of this study was to estimate the PPNA based on a model of efficiency in the use of light …
Germinable Soil Seed Bank Of Bothriochloa Macra Dominated Pasture In South-Eastern Australia, M. L. Mitchell, J. M. Virgona, A. Durling, F. W. Dempsey
Germinable Soil Seed Bank Of Bothriochloa Macra Dominated Pasture In South-Eastern Australia, M. L. Mitchell, J. M. Virgona, A. Durling, F. W. Dempsey
IGC Proceedings (1993-2023)
In native pastures, soil seed banks play an important role in conserving the genetic material in a plant population, influencing community structure and providing protection against adverse climatic conditions. One important native grass is Bothrichloa macra (Steud.) S.T.Blake (Red grass, Red-leg grass). This grass is a C4 indigenous perennial grass that is commonly found in native pastures in the high rainfall zone of south-eastern Australia.
At Tarrawingee, NE Victoria, (36°25´S, 146°31´E) and Wymah, southern NSW, (35°58´S, 147°11´E), Australia, two sites that had Bothriochloa macra as the dominant native grass were sampled. Three hundred cores (50 mm diameter and 50 …
Spatial And Time Distribution Of Dairy Cattle Manure In An Intensive Pasture System, S. L. White, S. P. Washburn, L. D. King, R. E. Sheffield, J. T. Green Jr.
Spatial And Time Distribution Of Dairy Cattle Manure In An Intensive Pasture System, S. L. White, S. P. Washburn, L. D. King, R. E. Sheffield, J. T. Green Jr.
IGC Proceedings (1993-2023)
This study determined distribution of feces and urine from dairy cattle managed in a rotationally grazed pasture. Lactating Holsteins (n=18) and Jerseys (n=18) were grazed on a .74 ha endophyte-free fescue (Festuca arundinacea)/white clover (Trifolium repens) pasture. All cows were constantly observed for 24 h 6 times over 12 mo. Cows had access to about 54% of the paddock during the first grazing period (12 h) and had access to the entire paddock during the second grazing period (8 h). Data included: (1) all feces and urine events from eight cows, observed while in the pasture, …
Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley
Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley
IGC Proceedings (1993-2023)
The effects of dairy cow manure on soil fertility were investigated at the site of the long-term phosphorus rate by stocking rate farmlet experiment at the Dairy Research Institute, Ellinbank, in Victoria. Manure increased extractable soil P (Olsen) in the 0 - 5 cm layer after 60 days to 61 mg/kg compared with values of 32 mg/kg in the control soils. Extractable soil K (Colwell) almost doubled under manure pads to 5 cm depth from 642 mg/kg in control soils to 1226 mg/kg in manure treated soils. The effects of grazing management on nutrient redistribution and pasture growth within strip-grazed …
Apparent Recovery Of Surface Applied Nitrogen Fertilizer By A Coastcross Pasture, A. C. Primavesi, O. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva
Apparent Recovery Of Surface Applied Nitrogen Fertilizer By A Coastcross Pasture, A. C. Primavesi, O. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva
IGC Proceedings (1993-2023)
Nitrogen recoveries from five levels of urea and ammonium nitrate surface-applied on coastcross pasture, grown on a dark red latosol (Hapludox), in São Carlos, SP, Brazil, under tropical altitude climate, were estimated. Significant differences occurred within periods (P < 0.05), depending on climatic conditions. Under adequate plant growth conditions, mean N recovery from urea was about 67%, sometimes reaching 80%, of that from ammonium nitrate. Recovery of ammonium nitrate varied from 45 to 68% of applied N.
Effect Of Soil Ph On Emergence And Survival Of Austrodanthonia Spp., M. A. Islam, P. M. Dowling, B. C. Jacobs, P. J. Milham, D. L. Garden, M. K. Conyers, R. Van De Ven
Effect Of Soil Ph On Emergence And Survival Of Austrodanthonia Spp., M. A. Islam, P. M. Dowling, B. C. Jacobs, P. J. Milham, D. L. Garden, M. K. Conyers, R. Van De Ven
IGC Proceedings (1993-2023)
We evaluated the effects of soil acidity on seedling emergence and seedling persistence of several ecotypes of Austrodanthonia spp. collected from the Central, Southern and Monaro Tablelands of New South Wales (NSW) in southern temperate Australia. A pot experiment was conducted outdoors to identify the most promising material tolerant to soil acidity for domestication. In the experiment, 183 ecotypes and two commercial cultivars of Austrodanthonia were grown in pots at three levels of pHCa (3.9, 4.4 and 5.3). The pH treatments were achieved by adding either aluminium sulphate or lime to an acid earthy sandy loam soil collected from …
Soil Nitrate Level Variation Under Intensive Nitrogen Fertilized Coastcross Pasture, O. Primavesi, A. C. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva
Soil Nitrate Level Variation Under Intensive Nitrogen Fertilized Coastcross Pasture, O. Primavesi, A. C. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva
IGC Proceedings (1993-2023)
Nitrate levels in soil profile after the first N application on coastcross pasture, grown on a dark red latosol (Hapludox), in São Carlos, SP, Brazil, under tropical altitude climate, were measured at 7-day intervals, to monitor possible losses in depth. Soil nitrate rates varied with high rates of N-ammonium nitrate (200 kg ha-1 per cutting) in surface layers. Danger of environmental impact was low in the studied conditions.
Soil Carbon And Nitrogen Dynamics After Pasture Installation In The Amazon Region, C. C. Cerri, M. Bernoux, C. E. P. Cerri
Soil Carbon And Nitrogen Dynamics After Pasture Installation In The Amazon Region, C. C. Cerri, M. Bernoux, C. E. P. Cerri
IGC Proceedings (1993-2023)
The objective of this paper is to present the soil carbon (C) and nitrogen (N) dynamics in a chronosequence made of a forest and pastures of different ages established in a Oxisol in the Western Brazilian Amazon Basin. The results of soil Carbon and Nitrogen stocks and gases fluxes were discussed. Stable 13C isotopic technique was used to calculate for a determinate age of pasture installation, the proportion of soil C remaining from the forest system and the proportion of soil C introduced by the grasses of the pasture system. The C lost from the original pool under the …
Pasture Seed Production Technology In Brazil, Ronaldo Pereira De Andrade
Pasture Seed Production Technology In Brazil, Ronaldo Pereira De Andrade
IGC Proceedings (1993-2023)
Efficient and low cost production systems, which rely on the use of cultivated pastures, are the basis of beef and milk production in Brazil. The success of these pasture-based systems would not be possible without the support of an aggressive and dynamic pasture seed production sector to supply the internal demand, which is estimated to be around 90000 tons per year. The market is dominated by grass species and among them, Brachiaria. brizantha cv. Marandu accounts for more than 80% of the total seed volume in the market. Seed production systems in Brazil vary from highly specialized to opportunistic accordingly …
Dry Matter Production Response Of Coastcross (Cynodon Dactylon (L.) Pears) To Sources And Rates Of Nitrogen, L. De A. Corrêa, H. Cantarella, A. C. Primavesi, O. Primavesi, A. R. Freitas, A. G. Da Silva, E. B. Pott
Dry Matter Production Response Of Coastcross (Cynodon Dactylon (L.) Pears) To Sources And Rates Of Nitrogen, L. De A. Corrêa, H. Cantarella, A. C. Primavesi, O. Primavesi, A. R. Freitas, A. G. Da Silva, E. B. Pott
IGC Proceedings (1993-2023)
Dry matter production of a coastcross pasture grown on a dark red latosol (Hapludox), in São Carlos, São Paulo State, Brazil, under tropical altitude climate, was evaluated. The goal was to verify the efficiency of N rates as urea and ammonium nitrate: 0, 25, 50, 100 and 200 kg ha-1 per cutting, in five periods. Both sources were equally efficient. The mean N rates, which produced 80% of maximum forage yield, were 78 and 58 kg N ha-1, respectively, for urea and ammonium nitrate, and were related to dry matter yields of 2,769 and 3,347 kg ha …
Ammonia Losses By Volatilization From Coastcross Pasture Fertilized With Two Nitrogen Sources, H. Cantarella, L. De A. Corrêa, A. C. Primavesi, O. Primavesi, A. R. De Freitas, A. G. Da Silva
Ammonia Losses By Volatilization From Coastcross Pasture Fertilized With Two Nitrogen Sources, H. Cantarella, L. De A. Corrêa, A. C. Primavesi, O. Primavesi, A. R. De Freitas, A. G. Da Silva
IGC Proceedings (1993-2023)
Ammonia losses by volatilization from five rates of urea or ammonium nitrate surfaceapplied to coastcross pasture, grown on a dark red latosol (Hapludox) in São Carlos, SP, Brazil, under tropical altitude climate, were measured. Volatilized ammonia was absorbed in traps placed on soil surface. The mean losses from urea applied after five successive cuttings of the grass were 15, 24, 34, and 40% for N rates of 25, 50, 100 and 200 kg N ha-1 per cutting, respectively.
Screening Brachiaria Introductions For Resistance To Spittlebugs (Homoptera: Cercopidae), José R. Valério, Cacilda Borges Do Valle, A. P. De Souza, M. C. M. Oliveira
Screening Brachiaria Introductions For Resistance To Spittlebugs (Homoptera: Cercopidae), José R. Valério, Cacilda Borges Do Valle, A. P. De Souza, M. C. M. Oliveira
IGC Proceedings (1993-2023)
Spittlebugs are the most evident and damaging pests of Signal grasses (Brachiaria) in tropical America. Damage caused by these insects can result in the complete loss of available forage, thereby reducing the carrying capacity of infested pastures. Host plant resistance is a low-cost method of controlling insects. High level of spittlebug resistance is found in the cultivar Marandu (B. brizantha), but it requires more fertile soils. Brachiaria germplasm provided by the International Center for Tropical Agriculture (CIAT) is available at National Beef Cattle Research Center of the Brazilian Agricultural Research Corporation (Embrapa Beef Cattle) and it …
Panicum Maximum Seeds From Sugarcane Plantations Improves Household Incomes In Uganda, P. Lusembo, C. Ebong
Panicum Maximum Seeds From Sugarcane Plantations Improves Household Incomes In Uganda, P. Lusembo, C. Ebong
IGC Proceedings (1993-2023)
No abstract provided.
Companion Crops For Pasture Establishment In The State Of Minas Gerais, Brazil, I. F. Andrade, P. Schmidt
Companion Crops For Pasture Establishment In The State Of Minas Gerais, Brazil, I. F. Andrade, P. Schmidt
IGC Proceedings (1993-2023)
No abstract provided.
Simulating Options For Managing Seasonal And Annual Variations In Feed Supply Of Mixed Crop/Livestock Systems In Sub‐Tropical Australia, Lindsay W. Bell
Simulating Options For Managing Seasonal And Annual Variations In Feed Supply Of Mixed Crop/Livestock Systems In Sub‐Tropical Australia, Lindsay W. Bell
IGC Proceedings (1993-2023)
No abstract provided.
Effect Of The Pasture On Milk Production From Cinisara Cows Over The Seasons, M. Alabiso, C. Giosuè, M. L. Alicata, V. Ilardi, D. Giambalvo, G. Maniaci
Effect Of The Pasture On Milk Production From Cinisara Cows Over The Seasons, M. Alabiso, C. Giosuè, M. L. Alicata, V. Ilardi, D. Giambalvo, G. Maniaci
IGC Proceedings (1993-2023)
No abstract provided.