Agricultural Science Commons^™

A Strategy For Detecting Natural Anthelmintic Constituents Of The Grassland Species Plantago Lanceolata, D. L. Gustine, M. A. Sanderson, J. Getzie, S. Donner, R. Gueldner, N. Jennings

IGC Proceedings (1977-2023)

A strategy to detect anthelmintic constituents in plantain (Plantago lanceolata) using a bioassay-driven purification approach was tested. Plantain consumed by cattle may control or reduce internal parasite titers, possibly due to the iridoid glucoside aucubin. Lyophilized, ground leaves of wild P. lanceolata were extracted with 95 % ethanol or boiling water containing calcium carbonate. Partially purified extracts (0 to 250 mg ml^-1), 5 μg ml^-1 of the anthelmintic levamisole, or 5 mg ml^-1 of aucubin were tested with sheathed bovine parasites (Ostertagia ostertagi). The percent moving worms was unchanged for water controls …

Tree Competition Reduces Cattle Growth Rates In Eucalypt Woodlands Of Queensland, T. J. Hall, J. R. Douglas

IGC Proceedings (1977-2023)

The wiregrass/bluegrass (Aristida/Bothriochloa) native pasture community in Eucalypt woodlands is a major cattle producing resource in Queensland. The effects of poplar box tree (Eucalyptus populnea) competition (at 5 m²/ha tree basal area) and grazing pressure on pastures and on growth of Brahman-cross steers were measured in a grazing experiment. Treatments were 2 tree competition levels (live trees or clearing) by 3 grazing pressures (low - 25%, medium - 50% and high - 75% utilisation of annual pasture growth). Pasture yield and pasture foliage cover increased for 3 years from the reduction in tree competition …

Perloline, The Forgotten Plant Alkaloid, L. P. Bush

IGC Proceedings (1977-2023)

Perloline, a biologically active plant alkaloid, accumulated in vegetative tissue of tall fescue during the summer months. Perloline content increased with increased available nitrogen and light. Total perloline accumulation was greatest with NO₃-N fertilizer, but greatest perloline content per unit of dry wt was measured with NH₄-N. In mature plants greatest perloline accumulation occurred in the leaves and immature inflorescences, but was not detected in the seed. Leaves of meadow fescue contained the greatest amounts of perloline, tall fescue was intermediate and giant fescue, and ryegrasses and yellow foxtail had low amounts of the alkaloid. Tryptophan …

Bloat In Ruminants: The Cell Rupture Hypothesis, B. P. Berg, T. A. Mcallister, K.-J. Cheng

IGC Proceedings (1977-2023)

An alfalfa (Medicago sativa L.) cultivar with a low initial rate of digestion (LIRD), AC Grazeland B, was developed to test the hypothesis that the rate of cell rupture was a cause of frothy bloat in cattle or sheep. The amount of cell wall increases and digestibility declines as plants mature. Thus the cell rupture theory also predicts that the bloat potential of alfalfa is related to maturity. This study compared the digestibility of cell walls (NDF) in LIRD cultivars with that of a standard, Beaver, in relation to maturity and bloat incidence. Fresh alfalfa was fed to wethers …

Effect Of Storage Time And Temperature On Recovery Of Synergistes Jonesii From Rumen Fluid And Feces, W. M. Andrew, M. J. Williams, M. J. Allison, C. C. Chase Jr., C. G. Chambliss, R. S. Kalmbacher, W. E. Kunkle

IGC Proceedings (1977-2023)

Synergistes jonesii is a rumen bacterium that degrades 3,4-dihydroxypyridine (3,4 DHP), the toxic breakdown product of mimosine in leucaena (Leucaena leucocephala). Fecal culture is the most practical way to determine S. jonesii presence in zoological ruminants, particularly if feces can be collected from night penning facilities. Fresh rumen fluid and fecal or fecal slurry (sheep [Ovis spp.] only, 1:4 wt to vol. feces and culture media) from cattle (Bos spp.) and sheep, known to be colonized by S. jonesii, were subjected various storage times (0, 6, 12, and 24 h) and temperatures (5, 23, and …

Extensive Livestock Production And Emerging Social Ethics For Animals, Bernard E. Rollin

IGC Proceedings (1977-2023)

The last 50 years have witnessed a dazzling array of social ethical revolutions in Western society. Such moral movements as feminism, civil rights, environmentalism, affirmative action, consumer advocacy, homosexual rights, children’s rights, the student movement, antiwar activism, public rejection of biotechnology, have forever changed the way governments and public institutions comport themselves. And this is equally true for private enterprise; to be successful, businesses must be seen as operating solidly in harmony with changing and emerging social ethics. It is arguable that morally based boycotting of South African business was instrumental in bringing about the end of apartheid, and similar …

The Importance Of Animal Comfort For Animal Production In Intensive Grassland Systems, P. H. Hemsworth, J. L. Barnett

IGC Proceedings (1977-2023)

Animals utilise a wide range of regulatory systems to control the conditions within their bodies or homeostasis. These regulatory systems control for example, body temperature, nutritional state, water balance, social interactions and fear and these systems react to environmental and endogenous stimuli so as to correct or prevent displacements from the optimal range. The behavioural and physiological responses utilised by the animal are usually proportional to the challenge to homeostasis. The stress response commences with the central nervous system perceiving a potential challenge to homeostasis. Once the central nervous system perceives a threat, it develops a biological response or defence …

Effect Of Caloric Stress On Milk Production And Animal Comfort, Mónica B. Sacido, F. Loholaberry, N. Sánchez, J. Intruvini

IGC Proceedings (1977-2023)

The objective of this study was to determine the effect of the environmental factors on the animal behaviour of grazing dairy cows, estimated through the THI (Temperature-Humidity Index) and the relationship with the daily milk production, quality of milk, consumption and the detection of zeal. The study was carried out in Azul , in the province of Buenos Aires, Argentina and was developed from December 1999 to February 2000. The effect of the half shade was quantified based on the production in litres of milk/day, % protein, % fat and detection of zeal. In the period analyzed, the THI usually …

Dags In Sheep Grazing Temperate Pastures: Causes And Consequences Of Faecal Adhesion To Wool, Garry C. Waghorn

IGC Proceedings (1977-2023)

Dags are the accumulation of faeces on wool in the perianal (breech) region of sheep and are a common problem in sheep fed good quality ryegrass based pastures in New Zealand. Their removal, or prevention, is costly but the consequences of doing nothing are severe. There is a high correlation between dags and flystrike (development of maggots) on sheep with dags, and dags reduce fleece value, live-weight gain and reproductive performance. Information summarised here suggests a range of factors contribute to the incidence of dags: lush (high quality) feeds, high voluntary feed intakes, presence of parasites in the gastro-intestinal tract, …

Nitrogen Fertiliser Effects On Perennial Ryegrass Nutritive And Nitrate Content During The Cool Season, Joseph L. Jacobs, Frank R. Mckenzie

IGC Proceedings (1977-2023)

A study was undertaken to determine the effects of differing levels of nitrogen (N) application (0 (N1), 25 (N2), 50 (N3) and 75 kgN/ha (N4)) during late autumn (T1), early (T2) and late winter (T3) on the nutritive characteristics and nitrate content of perennial ryegrass. Changes in crude protein (CP) for all treatments at each application time were similar irrespective of level of N application. At the commencement of all treatments, the existing CP content was highest in N3, followed by N2, N1 and N0. Nitrate content decreased throughout T1 primarily due to dry conditions, whilst during T2, levels for …

Nitrogen Concentration In Cell Wall Of Warm-Season Perennial Grasses, G. F. C. Lima, Lynn E. Sollenberger, J. E. Moore

IGC Proceedings (1977-2023)

The objectives of this experiment were to evaluate the influence of N fertilizer, age of regrowth, and season on concentration of N in cell-wall fractions of three warm-season perennial grasses (limpograss, [Hemarthria altissima (Poir.) Stapf et C.E. Hubb.], bermudagrass [Cynodon spp.], and bahiagrass [Paspalum notatum Flügge]. The herbage neutral detergent insoluble nitrogen (NDIN) fraction composed almost half of total N in these grasses. Though acid detergent insoluble nitrogen (ADIN) concentrations generally were 80 g kg^-1 of total N or less, this fraction is indigestible and unavailable and composes a significant portion of a nutrient that may …

Biological Behaviour Of Murrah Water Buffaloes, P. B. Alcântara, D. A. Beisman, V. B. G. Alcântara, A. M. F. Pereira

IGC Proceedings (1977-2023)

Modest but constant and progressive is the importance that buffaloes are achieving at the scientific’s, producer’s and consumer’s societies. Feeding behaviour is a continuous act in animals. Motivation is a reversible process of the brain induced by external factors. So, consumption tends to be continuous until another stimulus such as satiation becomes dominant. The majority of large domestic animals is fed “ad libitum”. This originates different situations when they are over or underfed. That is the situation that makes the cyrcadian rithm an important tool to be used in order to achieve maximum gains in rangelands. For half a year, …

Effect Of Burning And Management Alternatives On Forage Litter Composition Of A Native Pasture, I. Heringer, A. V. A. Jacques

IGC Proceedings (1977-2023)

The content and quantities of nutrients in forage and litter was evaluated in native pasture under grazing, submitted to burning and alternatives practices. The experimental design was a completely randomized, with three replications. The biennial burning has no effect in nutrients contents of the forage, but in the case of litter plus senescent material the concentration of Ca and Mg decreased as compared to the systems without burning. The sod-seeding treatment increased the nutrient contents in the alive and dead tissues. Nutrient accumulation on forage tissue and litter plus senescent material, was highest in the systems without burning.

Studies On Feeding Value For Five Psammophyte Shrubs In Ningxia Region, Dongmei X., Weixian C., Sijia G., Xiangyun X.

IGC Proceedings (1977-2023)

A trial was conducted on five psammophyte shrubs -Caragana intermedia, C. korshinskii, Hedysarum scoparium, H. laeve, Salix psammophylla in the post-fruit period in Ningxia, China. Chemical composition, palatability and in vitro digestibility were studied systematically. The feeding value was evaluated through Fuzzy multifactorial model. According to chemical composition, palatability and in vitro digestibility, C. intermedia, had the highest feeding value and C .korshinskii the lowest.

In Situ Dry Matter Ruminal Degradation Kinetics Of Prairie Grass And Annual Ryegrass Forage, J. R. Carrete, I. Ceconi

IGC Proceedings (1977-2023)

The objective of this study was to evaluate dry matter ruminal degradation kinetics, of prairie grass (Bromus catharticus Vahl.) and annual ryegrass (Lolium multiflorum), by using in sacco technique, on seven different harvesting dates. The forage was incubated in nylon bags, suspended in the rumen of four Hereford steers with a rumen fistula. The dry matter ruminal degradation was calculated through the exponential model P=a+b(1-exp(-ct)). Potential degradabilities (PD) were high and reduced across a temporal trend, ranging between 92,31 and 81,79g 100g ^-1 of dry matter (DM) for prairie grass (PG) and 95,06 and 77,44g 100g ^{-1 …}

Application Of Near Infrared Reflectance Spectroscopy (Nirs) To Forage Evaluation In Uruguay, D. Cozzolino, Y. Acosta, J. Garcia

IGC Proceedings (1977-2023)

Near infrared reflectance spectroscopy (NIRS) were used to assess the chemical composition of a wide range of forages. Nearly five hundred herbage samples covering a wide range of temperate pastures species and mixtures, previously analysed by conventional wet chemistry were scanned in reflectance with a NIRS 6500 (NIRSystems, Silver Spring, USA). The coefficients of determination in calibration (R² ) and the errors in cross validation (SECV) were 0.98 (5.8), 0.94 (22.2), 0.97 (5.6), 0.94 (6.9) and 0.89 (19.7) for crude protein, in vitro organic matter digestibility, dry matter, ash and acid detergent fiber, in g kg ^–1 on a …

Seasonal Variation Of Brachiaria Spp. Quality In The Pantanal Of Mato Grosso Do Sul, Brazil, S. M. A. Crispim, E. L. Cardoso, F. Fernandes

IGC Proceedings (1977-2023)

This study aims to evaluate the dry matter yield and the crude protein (CP) of Brachiaria decumbens and Brachiaria humidicola and soil covering by these species, considering stand lasting age and hydrologic cycle periods in the Pantanal, from November 1996 to November 1997. Dry matter yield presented differences between hydrologic cycle periods and age, and their interactions. B. decumbens and B. humidicola over 10 years comparison yielded the largest amount of dry matter yield, observed in February. B. humidicola growth rate was slower than B. decumbens. Pastures stand ages did not cause differences in crude protein, but differences have …

Continuous Digestibility Assessment Of Tropical Grasses, A. Chudy, T. Schmidt, A. Glatzle

IGC Proceedings (1977-2023)

The feed value for cattle of three tropical grasses, Gatton (Panicum maximum cv. Gatton), Estrella (Cynodon plectostachyus) and Tifton-85 (Cynodon sp. cv. Tifton-85) was investigated during the growing period, using the method of “continuous digestibility estimation”. Results indicate that feed value is hardly influenced by the growth stage from the 90th day on. Common European in-vitro feed evaluation procedures are not to be recommended for tropical grasses as they presented consistently lower values than did in-vivo measurements.

Prediction Of Intake Of Hay Differing In Species And Maturity By Goats, S. W. Coleman, S. P. Hart, T. Sahlu

IGC Proceedings (1977-2023)

Eight species of forage, a cool-season perennial (Festuca arundinacea) and annual grass (Triticum aestivum), four warm-season perennial grasses (Bothriochloa caucasica, B. ischaemum, Cynodon dactylon, and Tripsacum dactyloides), a warm season annual (Digitaria sanguinalis) and a perennial legume (Medicago sativa), were cut at two or three maturities to provide a wide array of quality difference (n=20). Twenty wether goats (Capra hicus) were fed the hays in four different trials using an incomplete block so that each hay was fed to four different goats. Alfalfa produced the highest DM, …

Climatic Factors, Acid Detergent Fiber, Neutral Detergent Fiber And Crude Protein Contents In Digitgrass, C. S. Chen, S. M. Wang, Y. K. Chang

IGC Proceedings (1977-2023)

Digitgrass (Digitaria Xumifolia) was treated according to a set of programmed harvest cycles to study the impact of climatic factors on the quality of the grass. It is found that seasonal changes have greater effect on the quality of the grass than does the length of the harvest cycle. The highest correlation coefficient (0.81) between the ADF content and accumulated temperature is attained when the base temperature is set to 15.5 , while the highest correlation coefficient (0.88) between CP and is attained at a base temperature of 15.0 . The determination coefficient of regression (R² ) …

Effect Of Level Of Surface Spoilage On The Nutritive Value Of Maize Silage Diets, K. K. Bolsen, L. A. Whitlock, G. L. Huck, M. K. Siefers, T. E. Schmidt, R. V. Pope, M. E. Uriarte

IGC Proceedings (1977-2023)

This study determined the effect of surface spoilage in the diet on feed intake and nutrient digestibilities using growing steers fed whole-plant maize silage-based diets. A bunker silo, 0.9 m in depth, and a 2.7 m diameter AgBag were filled with alternating loads of chopped forage. After 90 days, the bunker was sealed with a sheet of polyethylene, and this silage was designated “spoiled”. The silage in the AgBag was designated “normal”. The four diets contained 90% silage and 10% supplement (dry matter basis), and the proportions of silage in the diets were A) 100% normal, B) 75% normal: 25% …

Selenium And Sulphur Concentrations In Primary Growths Of Different Plant Communities, W. Opitz Von Boberfeld

IGC Proceedings (1977-2023)

The factorised evaluated data of seven different grassland swards and two harvest dates of primary growths led to following results: Regarding the concentrations of selenium and sulphur, a selenium antagonist, and the N/S ratio, there were no significant plant community x harvest date, plant community x year, and harvest date x year interactions. The selenium concentrations, which never met the requirements of ruminants, were the highest in young herbage of a Bromion racemosi community reaching 49 µg kg^-1 DM. The average of all swards and treatments was 33 µg kg^-1 DM of selenium. Apparently, repeated application of selenate-bearing …

Canopy Characteristics, Ingestive Behaviour And Herbage Intake In Cultivated Tropical Grasslands, Lynn E. Sollenberger, J. C. Burns

IGC Proceedings (1977-2023)

Compared to temperate systems, there have been few detailed assessments of canopy characteristics and associated grazing behavior in planted tropical grasslands. Reasons include the large number of forage species used in warm climates, the diversity of their morphology, research priorities emphasizing germplasm evaluation and management, and limited resources. This review describes canopy attributes of C₄ grass pastures, highlights the most important relationships between grazing behavior and these canopy characteristics, and discusses the implications of canopy characteristics and grazing behavior for long-term intake and animal performance. It is suggested that the largest differences in canopy characteristics between tropical and temperate …

Foraging Behaviour And Intake In Temperate Cultivated Grasslands, S. Prache, J. L. Peyraud

IGC Proceedings (1977-2023)

In temperate areas, grazing provides a large part of the nutrient requirements of ruminants and may be an important form of land use. In Europe, grassland occupies some 150 million hectares, and grazing provides about 60 to 75% of the nutrient requirements of cattle (Wilkins and Vidrih 2000). From the end of the 80’s, agricultural surpluses in Europe have led to production quotas and increased interest in more extensive systems. At the beginning of the 90’s, the emergence of the notion of sustainable agriculture combining economic, social (concerns in dereliction of less-favoured rural areas), and environmental issues (pollution, loss of …

A Comparative Grazing Study Of Sheep And Cattle Diet Selection On Native Pastures In Uruguay, Fabio Montossi, G. Pigurina, E. J. Berretta, I. Santamarina

IGC Proceedings (1977-2023)

An experiment was carried out during winter, spring and summer 1997, on native pastures of the basaltic region of Uruguay to evaluate the effects of different herbage mass levels (high, medium and low) on sward characteristics and on sheep and cattle diet selection and grazing behaviour. Higher herbage masses resulted in increments in herbage accumulation and sheep bite weight: winter (1880, 1513 and 610 kg DM ha-1, P < 0.01; 199, 148 and 128 mg DM/bite, P < 0.01), and summer (3046, 2175 and 1172 kg DM ha-1, P < 0.01; 214, 175 and 143 mg DM/bite, P < 0.01) for high, medium and low herbage mass levels respectively. The nutritive value of diet selected by sheep and cattle was higher than that of the herbage on offer, and higher in sheep than in cattle: winter (10.2, 15.9 and 12.5% crude protein, CP, P < 0.05; 49.2, 32.4 and 38.1% acid detergent fiber, ADF, P < 0.01, and summer (7.4, 10 and 9.5% CP, P < 0.05; 51.1, 36.8 and 43% ADF, P < 0.01) for herbage on offer, sheep and cattle diets respectively. These contrasting results found in the nutritive value were closely associated with differences in the proportions of the botanical components recorded, particularly the differential contribution of dead material. This experiment quantified the importance of diet selection in determining the nutritive value of the forage eaten by sheep and cattle on the native pastures of the basaltic region of Uruguay and established some relationships between diet selection and grazing management, involving animal selectivity ability differences (sheep versus cattle) and seasonal effects.

A Sheep And Catlle Diet Selection Study On A Fertilized Native Sward In Uruguay, Fabio Montossi, E. J. Berretta, G. Pigurina, I. Santamarina

IGC Proceedings (1977-2023)

This study was undertaken during winter, spring and summer 1997, located in the basaltic region of Uruguay to evaluate the effects of stocking rate (SR) and N and P fertilizer application on sward characteristics and on sheep and cattle diet selection and grazing behaviour. The treatments applied were: a) control (C; without fertilizer application using a SR of 0.9 stock units (SU)/ha), b) T1 (with N and P fertilizer application using a SR of 0.9 SU/ha), c) T2 (with N and P fertilizer application using a SR of 1.2 SU/ha) and d) T3 (with N and P fertilizer application using …

Ingestive Behavior Of Beef Cattle Fed Either Protein Or Energy Supplements Under A Rotational Grazing System, R. P. Manzano, Luiz Gustavo Nussio, M. P. Andreucci, K. Z. Veiga, R. Z. M. Costa

IGC Proceedings (1977-2023)

Eight Nellore bullocks were assigned to a Tanzânia grass pasture (Panicum maximum Jacq.) under a rotational grazing system, to evaluate the ingestive behavior under two different grazing residues. Stocking rate intensity was used to reach either 1000 kg DM.ha^-1 (R1) or 4000 kg DM.ha^-1 (R2) as residual targets. Three grazing days followed by 33 days resting period, composed a 36 day grazing cycle. Each grazing plot supported four animals, in a 4x4 Latin square design, within the following supplementation rates and sources: S1 = no supplement; S2 = 2,0 kg DM.day^-1 coarsely ground corn - 8 …

Changes In Pasture Growth Rate Due To Fertiliser And Grazing Management, P. Quigley, D. Chapman, J. Lamb, G. Kearney

IGC Proceedings (1977-2023)

It is imperative that sheep production systems in southern Australia continue to be refined so producers remain financially viable but at the same time the environment is not degraded. As part of a national thrust for development and promotion of better production systems, one research site has been established in Victoria where pastures and animal production are measured together with water and nutrient movement. Results for pasture growth rates over two years are presented here and will be used to develop best industry practice at completion of the project.

2022 Western Australian Crop Sowing Guide, B. Shackley, B. Paynter, J. Bucat, M. Seymour, S. Power

Bulletins 4000 -

Welcome to the 2022 edition of the Crop Sowing Guide for WA, which introduces 27 new variety releases: three wheat, nine barley (three recently accredited for malt and six currently under malt evaluation), twelve canola, two field pea and a lentil.

The Crop Sowing Guide for WA has been compiled by officers in the Department of Primary Industries and Regional Development. It provides information to support variety decisions for each of the major crops for the upcoming season.

In this edition, lupin agzones have been reduced from 8 agzones to 6 so that all varieties for each of the major …

Identification And Validation Of High Ld Hotspot Genomic Regions Harboring Stem Rust Resistant Genes On 1b, 2a (Sr38), And 7b Chromosomes In Wheat, Shamseldeen Eltaher, Amira M.I. Mourad, P Stephen Baenziger, Stephen Wegulo, Vikas Belamkar, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Stem rust caused by Puccinia graminis f. sp. tritici Eriks. is an important disease of common wheat globally. The production and cultivation of genetically resistant cultivars are one of the most successful and environmentally friendly ways to protect wheat against fungal pathogens. Seedling screening and genome-wide association study (GWAS) were used to determine the genetic diversity of wheat genotypes obtained on stem rust resistance loci. At the seedling stage, the reaction of the common stem rust race QFCSC in Nebraska was measured in a set of 212 genotypes from F3:6 lines. The results indicated that 184 genotypes (86.8%) had different …