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An Unusual Instance Of Mortality In The Barn Swallow, Ren Lohoefener Sep 2024

An Unusual Instance Of Mortality In The Barn Swallow, Ren Lohoefener

Mississippi Kite

No abstract provided.


Requests For Information: Sightings Of Color-Banded Killdeer, Bette J. Schardien Sep 2024

Requests For Information: Sightings Of Color-Banded Killdeer, Bette J. Schardien

Mississippi Kite

No abstract provided.


Extensive Ground Foraging By Pileated Woodpeckers In Recently Burned Pine Forests, Bette J. Schardien, Jerome A. Jackson Sep 2024

Extensive Ground Foraging By Pileated Woodpeckers In Recently Burned Pine Forests, Bette J. Schardien, Jerome A. Jackson

Mississippi Kite

No abstract provided.


Reviews, J. A. Jackson, Ray E. Weeks, Dave Werschkul Sep 2024

Reviews, J. A. Jackson, Ray E. Weeks, Dave Werschkul

Mississippi Kite

No abstract provided.


Reviews, W. C. Weber, J. A. Jackson Sep 2024

Reviews, W. C. Weber, J. A. Jackson

Mississippi Kite

No abstract provided.


Reviews, J. A. Jackson Sep 2024

Reviews, J. A. Jackson

Mississippi Kite

No abstract provided.


Nesting Records Of The Worm-Eating Warbler In Mississippi, W. H. Turcotte Sep 2024

Nesting Records Of The Worm-Eating Warbler In Mississippi, W. H. Turcotte

Mississippi Kite

No abstract provided.


The Winter Roosts And Food Habits Of Marsh Hawks In East Central Mississippi, Jerome A. Jackson, Michael W. Roberts, James E. Wright Sep 2024

The Winter Roosts And Food Habits Of Marsh Hawks In East Central Mississippi, Jerome A. Jackson, Michael W. Roberts, James E. Wright

Mississippi Kite

No abstract provided.


The Breeding Biology And Distribution Of Swainson's Warbler In Mississippi, W. H. Turcotte Sep 2024

The Breeding Biology And Distribution Of Swainson's Warbler In Mississippi, W. H. Turcotte

Mississippi Kite

No abstract provided.


Birding In The Rio Grande Valley, B. Quentin, Frances L. Dowdy Sep 2024

Birding In The Rio Grande Valley, B. Quentin, Frances L. Dowdy

Mississippi Kite

No abstract provided.


In Memoriam: Miss Fannye A Cook, B. E. Gandy Sep 2024

In Memoriam: Miss Fannye A Cook, B. E. Gandy

Mississippi Kite

No abstract provided.


Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario Sep 2024

Photosynthesis And Water Relations Of Two Savanna Grasses As Influenced By Shade And Water Stress, M J. Trlica, J I. Kinyamario

IGC Proceedings (1977-2023)

Net CO2 assimilation and plant water relations of the African savanna grasses Panicum maximum Jacq. and Tliemeda triandra Porrsk. were measured under controlled conditions. We hypothesised that 1; triandra would be better adapted to higher light and temperature conditions and could withstand greater moisture stress than could P. maximum, as T. tria11dra is commonly found in open areas, whereas P. maximum dominates in the shade of trees. Plants of both species were transplanted into a common soil in large pots and placed under shade (approximately 150 µrnoVm1/s photon flux density (PFD)) or high light (approximately 1200 µmoVm1/s PFD) conditions, with …


Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez Sep 2024

Defoliation Of Young Branch And Parent Stolons Of White Clover In Rotationally Grazed Pastures, M.J M. Hay, M Kim, R W. Mclean, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

This study was undertaken to examine the relative severity of defoliation of young branches (those comprising <4 nodes) and parent stolons of white clover (Trifolium repens L.) in rotationally grazed pastures stocked al either 2.5, 5.0 or 7.5 bulls/ha. On 7 occasions over a year, the defoliation of expanded leaves of parenl and branch stolons was assessed using tagged stolons. Petiole length of leaves ,vas measured before grazing. Leaves of young branch stolons (43% of the total number of leaves defoliated) were less severely defoliated than leaves of parent stolons (64%). Defoliation of branch stolon leaves was relatively greater at the higher stocking rates which had lower residual …


Improving Germination And Seedling Establishment Of Chicory, S N. Hur, W F. Hunt Sep 2024

Improving Germination And Seedling Establishment Of Chicory, S N. Hur, W F. Hunt

IGC Proceedings (1977-2023)

Chicory (Cichorium intybus L.) seeds were treated before sowing with polyethylene glycol (PEG 6000) under different PEG concentrations, treatment period and temperatures, and tested for uniformity of germination, establishment and drought tolerance. Suitable seed coating materials were found that improved emergence, establishment and seedling growth when surface sown on established swards. The best primed or coated seeds in germination tests were surface sown in growth cabinet and field.Osmotic priming with PEG accelerated germination of chicory and significantly reduced time taken for germination compared with coated seeds in Petri-dishes, but not in the field. In contrast, coated seeds germinated more slowly …


Growth Of Temperate Perennial Legumes Over Three Cycles Of Defoliation At Different Temperatures, M A.P Duarsa, M J. Hill, J V. Lovett Sep 2024

Growth Of Temperate Perennial Legumes Over Three Cycles Of Defoliation At Different Temperatures, M A.P Duarsa, M J. Hill, J V. Lovett

IGC Proceedings (1977-2023)

Summer-active legumes such as big trefoil (Lollis ped11nc11lat11s), birdsfool trefoil (Lot11s comic11la111s), crownvelch (Coronilla varia) and cicer milkvetch (Astraga/11s cicer) are needed for summer rainfall areas of the perennial pasture zone in eastern Australia where soil conditions and grazing management do not suit lucerne (Medicago sativa). The growth of these species was compared at 4 temperatures regimens (14/10, 18/14, 22/18, 26/22°C, 12:12 h) for 3 cycles of regrowth where soil moisture was serially changed from field capacity (FC) to 50% PC and back to PC in a growth cabinet pot experiment. Growth rates in lucerne always exceeded those of the …


Nutrient Cycling In Semi-Arid Grasslands And Savannas: Its Influence On Pattern, Productivity And Stability, Robert J. Scholes Sep 2024

Nutrient Cycling In Semi-Arid Grasslands And Savannas: Its Influence On Pattern, Productivity And Stability, Robert J. Scholes

IGC Proceedings (1977-2023)

The grazing animal carrying capacity of tropical semi-arid rangelands is largely controlled by rainfall, but above about 500 mm per annum, soil nutrient status has an overriding role. On low-nutrient soils, which cover vast areas of the ancient land surfaces of Africa, South America and Australia, it is the amount of grass eaten and digested that controls animal production, not the amount produced. On nutrient­poor soils (particularly those deficient in nitrogen and phosphorus) the primary production continues to increase with increasing rainfall, but the acceptability of the forage to ruminants declines, On the nutrient-rich soils of younger land surfaces, both …


Soil Characteristics And Processes Critical To The Sustainable Use Of Grasslands In Arid, Semi-Arid, And Seasonally Dry Environments, John Williams, Keith R. Helyar, Richard S.B Greene, Rosemary A. Hook Sep 2024

Soil Characteristics And Processes Critical To The Sustainable Use Of Grasslands In Arid, Semi-Arid, And Seasonally Dry Environments, John Williams, Keith R. Helyar, Richard S.B Greene, Rosemary A. Hook

IGC Proceedings (1977-2023)

The focus of this paper is a framework for determining the soil and land properties and processes which are critical to managing grasslands in an ecologically sustainable manner. Essential to the discussion is the development of concepts which allow description of the stability, resilience and sustainability of the agroecosystem as a whole as well as the land resource base. The regions of Australia with arid, semi-arid and seasonally dry environments are defined and related to the dry environments of the world. This provides a background for a brief consideration of major vegetation types and soils within the dry environments of …


Soil Animal Composition And Distribution In The Leymus Chinensis Grassland Region In Central Part Of North-East Of China, Yin Xiuqin, Li Jiandong, Zhu Tingcheng Sep 2024

Soil Animal Composition And Distribution In The Leymus Chinensis Grassland Region In Central Part Of North-East Of China, Yin Xiuqin, Li Jiandong, Zhu Tingcheng

IGC Proceedings (1977-2023)

Since 1990, we have investigated the soil animal composition and distribution in the Leymus chinensis (Aneuro chinensis) grassland region in central part of north-east of Chinn. Soil animals were studied in 20 plant communities in 4 habitats. A total of 15 797 soil animals belonging to 4 phyla, 6 classes, 28 orders and 86 families were obtained. Among them, 26 families and 22 species were new records in norlh-easl of China. The dominant groups were Formicidne, Actinedida, Oribatidn, lsotomidne, Rhnbditidae, Dorylainidae. Sparse woods of Ulmus, and the most animal groups (40) and Puccinellia chinapoesis and Heleochalis intersiIa …


Intensive Grazing Systems And Methods For Beef Cattle, V G. Allen, J P. Fontenot, M A. Cochran, A Brock, W Mcclure, J Wilkins Sep 2024

Intensive Grazing Systems And Methods For Beef Cattle, V G. Allen, J P. Fontenot, M A. Cochran, A Brock, W Mcclure, J Wilkins

IGC Proceedings (1977-2023)

Three experiments were conducted to determine effects of grazing systems and methods on beef production. In experiment 1, cows, calves and stockers grazed tall fescue-clover (Festuca arundinacea-Trifolium repens) in a l 6-paddock system using rotational stocking or a 3-paddock system using continuous stocking as grazing methods. In experiment 2, stocker steers grazed orchardgrass-clover (Dactylis glomerata-Trifolium pratense) using buffer grazing with continuous stocking or a 14-paddock rotational stocking method. In experiment 3, 4 grazing systems were compared using sequence grazing combinations of cool-and warm­seasoo perennial and annual forages. In experiments l and 2, there were no differences in …


Selection Pattern Of Holstein-Zebu Cows Grazing Stoloniferous And Tufted Type Tropical Grasses In A Cafeteria Type Trial, Francise E. Davis Sep 2024

Selection Pattern Of Holstein-Zebu Cows Grazing Stoloniferous And Tufted Type Tropical Grasses In A Cafeteria Type Trial, Francise E. Davis

IGC Proceedings (1977-2023)

Seven stoloniferous and 7 tufted grasses are being evaluated in a long­term trial on an acid ultisol in Trinidad in duplicate 3x3 m plots. The grasses were cut at five weekly intervals and nitrogen at 40 kg/ha applied after every harvest. A basal dressing of 125 kg P20��, and 100 kg '½O and a trace element mix was applied twice annually. After culling in May 4 milking cows were allowed to graze the area. There was no significant difference in dry matter yield between the stoloniferous and tufted grasses, but there were significant differences within each type of grass in …


Effect Of Percentages Calluna Vulgaris Cover And Cow And Ewe Physiological Status On Animal Production On Mountain Pastures, K Osoro, R Celaya, Mamen Olivan Sep 2024

Effect Of Percentages Calluna Vulgaris Cover And Cow And Ewe Physiological Status On Animal Production On Mountain Pastures, K Osoro, R Celaya, Mamen Olivan

IGC Proceedings (1977-2023)

The effect percentage cover of Calluna vulgaris (30 or 70%) on performance of dry and lactating ewes and cows with their lambs and calves was studied during 1990 and 1991. Lactating cows had greater body weight losses than dry ones, the difference being 0.3 and 0.S kg/day for 1990 and 1991 respectively. Percentage C.vulgaris cover (30 or 70%) caused differences in body-weight losses· similar to those caused by physiological status. Milk production from the cows, and therefore calf live-weight gain, were significantly higher in the group grazing on the plot with 30% Calluna (0.62 and 0.71 kg/day for 1990 …


Adaptation Of Some Grass Species To Grazing, Marc Ghesquiere, J C. Emile, X Charrier, R Traineau Sep 2024

Adaptation Of Some Grass Species To Grazing, Marc Ghesquiere, J C. Emile, X Charrier, R Traineau

IGC Proceedings (1977-2023)

To examine the grazing behaviour of some grass species, 2 linked trials were set up in Lusignan (France), Dry matter yields of 10 species were recorded by frequent mechanical cuts (every 15 days) and compared with the ability to feed sheep under continuous grazing management. The dry matter yield of the genotypes ranged from 5600 to 8600 kg DM/ha and the grazing yield from 86 to 183 days x animal. The well-known species, such as Bromus siIchensis L., 8. caIhar1ic11s L. and Dactylis glomerata L. usually used in farms allowed high dry matter and grazing yields, but some secondary species …


Crop Processing And Fractionation As A Commercial Proposition To Forage-Based Animal Systems, H T. Ostrowski-Meissner Sep 2024

Crop Processing And Fractionation As A Commercial Proposition To Forage-Based Animal Systems, H T. Ostrowski-Meissner

IGC Proceedings (1977-2023)

The paper outlines crop processing and fractionation technology as it applies to an intensive forage-based operation with beef cattle, The benefits of forage processing prior to its feeding to cattle are described with an emphasis not only on the uniformity of the nutritive quality of the processed product but also on the extra financial benefits resulting from the wet fractionation process. The value-added primary products from the fractionation process ensure extra return to the. forage producers, crop processing installation and the feedlot operation. The characteristics of the fractionation products derived from lucerne and other crops are described.


Integrated Grazing Of Goats With Sheep Or Cattle On Continuously Grazed Pasture, A M. Nicol, A.J F. Russel, I A. Wright Sep 2024

Integrated Grazing Of Goats With Sheep Or Cattle On Continuously Grazed Pasture, A M. Nicol, A.J F. Russel, I A. Wright

IGC Proceedings (1977-2023)

Oroups of ewes (10) and their twin lambs were grazed on sown ryegrass• white clover (Lolium perenne L.-Trifollum repens L.) pastures maintained at a sward surface height of 4 or 8 cm and a further group grazed with yearling goats (in a proportion of 1/3 ewe plus lamb live weight) also at fi cm. A second concurrent experiment consisted of 3 similar treatments using young cattle with sward surface heights of 8 and 12 cm. Results over the 140-day grazing period showed that allhough the diet selected by sheep and cattle grazed with goats contained more green grass …


Herbage And Animal Production From Tall Fescue- And Ryegrass-Based Pastures In A Summer-Dry Environment, D E. Hume, R.J M. Hay, T B. Lyons Sep 2024

Herbage And Animal Production From Tall Fescue- And Ryegrass-Based Pastures In A Summer-Dry Environment, D E. Hume, R.J M. Hay, T B. Lyons

IGC Proceedings (1977-2023)

Herbage production and animal performance were measured over 3 years In Hawkes Bay, a summer-dry region of New Z'.ealand. Tall rescue (Festuca arundinacea) (3 cultivars, all endophyte free) was compared with high endophyte perennial ryegrass (Lolium perenne). All pastures were sown with white clover (Trifolium repens). Herbage production and composition were determined for all seasons while cattle were monitored for live-weight gains from spring through to autumn. Tall fescue pastures produced 27% more total dry matter/ year than the ryegrass pasture, primarily in autumn. In summer­autumn, ryegrass pastures had up to 76% dead matter …


Climate Change: Adapting Tropical And Subtropical Grasslands, G M. Mckeon, S M. Howden, N.O J. Abel, J M. King Sep 2024

Climate Change: Adapting Tropical And Subtropical Grasslands, G M. Mckeon, S M. Howden, N.O J. Abel, J M. King

IGC Proceedings (1977-2023)

Climate change as a result of increasing greenhouse gas concentrations or lhe repetition of historical climale variability will affect the management and production of tropical and subtropical grasslands that support about half the world's domestic herbivores. Previous studies of the regional impact of climate change and climate variability on intensive agriculture have shown lhat such evaluation should include the known and expected abilities of managers and governments to respond by reducing the negative impacts and taking advantage of positive opportunities, A high priority for grassland scientists is the development of similar evaluation capabilities for grassland systems, which are more complex …


Methane Production By New Zealand Ruminants, K Betteridge, M J. Ulyatt, J Knapp, R L. Baldwin Sep 2024

Methane Production By New Zealand Ruminants, K Betteridge, M J. Ulyatt, J Knapp, R L. Baldwin

IGC Proceedings (1977-2023)

Methane production by ruminants in New Zealand was estimated using a ma1hema1ical model of rumen digestion interfaced with census livestock numbers. New Zealand was divided into 4 climatic regions with each classified into improved, unimproved and tussock grasslands, and livestock were allocated to each class at appropriate stocking rates. Models of changing livestock numbers within n year were developed for each animal and land class. Food dry matter intake for each class of livestock was calculated from estimates of feed requirements and diet quality. Total methane production was estimated to be 1.50 Tg per year: 58.4% sheep, 20.7%, beef cattle, …


Nitrous Oxide Emissions From Grassland In Manawatu, New Zealand, R A. Carran, J P. Evans Sep 2024

Nitrous Oxide Emissions From Grassland In Manawatu, New Zealand, R A. Carran, J P. Evans

IGC Proceedings (1977-2023)

Nitrous oxide (Np) is a minor component of the atmosphere which acts as a potent greenhouse gas and also causes ozone depletion. Soil bacteria are the most important agents of N2O production, but both the New Zealand and the international data on N2O emission rates from soils are very poor at present. In order to help define the possible range of emission ranges from pasture soils· we selected sites with characteristics that would make then "high" or "low" emitters of N2O. The "high" emission site was a fine-textured, fertile but poorly drained flood plain soil. The "low" emission site was …


Development Of Plants Resistant To Insect Pests Using Gene Manipulation, D.W R. White, D R. Biggs, M T. Mcmanus, C R. Voisey, J T. Christeller, A H. Broadwell, E.P J. Burgess, C N. Chilcott, P J. Wigley, P G. Mcgregor Sep 2024

Development Of Plants Resistant To Insect Pests Using Gene Manipulation, D.W R. White, D R. Biggs, M T. Mcmanus, C R. Voisey, J T. Christeller, A H. Broadwell, E.P J. Burgess, C N. Chilcott, P J. Wigley, P G. Mcgregor

IGC Proceedings (1977-2023)

Damage to pasture plants caused by insect pests reduces the supply of feed for grassland animal production. In addition, the use of chemical insecticides for the control of pasture pests is undesirable for reasons of high cost and possible damage to the environment. One way to overcome these limitations is 10 utilize a recent development. in plant molecular biology which has seen the incorporation of cloned genes that confer insect _pest resistance into crop plants. To date, the most widely used genes for this purpose are those coding for insecticidal proteins from the bacterium Bacillus thuringiensis, and for inhibitors …


Implications Of A Doubling In Ambient Carbon Dioxide Levels Of Herbage Quality In Perennial Ryegrass And White Clover, H Clark, C C. Bell, P.C D. Newton, B D. Campbell Sep 2024

Implications Of A Doubling In Ambient Carbon Dioxide Levels Of Herbage Quality In Perennial Ryegrass And White Clover, H Clark, C C. Bell, P.C D. Newton, B D. Campbell

IGC Proceedings (1977-2023)

Digestibility (DMD) and crude protein (CP) percentage in leaf and stem of 4 cultivars each of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) grown at 3 day/night temperatures (12f7, 18/ 13, 28/23°C) and 2 CO2 concentrations (35 0 or 700 ppm) was estimated using near infrared reflectance spectroscopy (N[RS). Differences between cultivars in DMD and CP were small and non-significant. Higher temperatures reduced DMD andCP in both species. DMD was unaffected by CO2 concentration in either species. The higher concentration of CO2 reduced leaf and stem CP by 14.6 and 10% respectively in white clover …