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Insecticidal Activity Of N-Formylloline, D L. Dahlman, M R. Siegel, L P. Bush Jun 2024

Insecticidal Activity Of N-Formylloline, D L. Dahlman, M R. Siegel, L P. Bush

IGC Proceedings (1993-2023)

Several insect species were sensitive to N-formylloline, a pyrrolizidine alkaloid found in significant concentrations in tall fescue (Festuca arundinacea L.) infected with Neotyphodium coenophialum (= Acremonium coenophialum) Glenn, Bacon et Hanlin. Topical or injected doses were toxic in a dose dependent manner. Acute doses resulted in quick incapacitation; lower doses caused behavioral changes, uncoordinated movements, tremors, etc. Insects tested included green bug, bird cherry-oat aphid, large milkweed bug, spined soldier bug, American cockroach, house fly, face fly, cat flea and Japanese beetle.


Autecology Of Prosopis Caldenia (Burk.) In The Region Of "Caldenal" Of The Province Of San Luis, Argentina, G E. Gabutti, M.J L. Privitello Jun 2024

Autecology Of Prosopis Caldenia (Burk.) In The Region Of "Caldenal" Of The Province Of San Luis, Argentina, G E. Gabutti, M.J L. Privitello

IGC Proceedings (1993-2023)

Different estimates of the growth of Prosopis caldenia (Burk.) were related in the area of the “caldén” forest, Province of San Luis: trunk diameter, treetop coverage and total tree height to infer the annual growth percentage. The number of trees per hectare and their distribution was calculated based on size. Pod production per hectare was evaluated to determine forage potential.


Variation In The Stylosanthes Anthracnose Pathogen: Implications For Australian Cultivars, Sukumar Chakraborty, Ross Perrott, Maria Jose D'A Charchar, Celso D. Fernandes, Segenet Kelemu Jun 2024

Variation In The Stylosanthes Anthracnose Pathogen: Implications For Australian Cultivars, Sukumar Chakraborty, Ross Perrott, Maria Jose D'A Charchar, Celso D. Fernandes, Segenet Kelemu

IGC Proceedings (1993-2023)

Isolates of Colletotrichum gloeosporioides which cause anthracnose disease in the tropical pasture legume Stylosanthes were collected from its centre of diversity in South America. These and other isolates from Asia, Africa and Australia were studied using Random Amplified Polymorphic DNA (RAPD) markers and virulence on host differentials to assess the threat to Australian Stylosanthes cultivars from exotic races of this pathogen. A phenetic analysis of 90 isolates using RAPD markers showed a wide genetic diversity in the overall pathogen population. Compared to this, genetic diversity in the Australian population was very limited. A similar situation was noted for pathogenic variation …


Pfra Grazing Management Conserves Biodiversity, B Bristol, T Weins Jun 2024

Pfra Grazing Management Conserves Biodiversity, B Bristol, T Weins

IGC Proceedings (1993-2023)

Shrinking grassland habitats across Prairie Canada are resulting in increased societal values for biodiversity within the remaining rangeland resources. The Prairie Farm Rehabilitation Administration (PFRA) manages 929,000 hectares in the Prairie and Boreal Plain Ecozones across three Prairie Provinces. Management of these range resources accomplishes two main objectives: (1) sustaining economic viability of the rural community through provision of livestock grazing and (2) conservation of soil, water and biodiversity resources. PFRA uses the tools of inventory, research and management to accomplish these objectives. The 87 pastures are managed toward the “good and excellent” range condition classes which conserves biodiversity and …


Study Of The Diversity Of Soil Animal Community In The Songnen Plain Grassland Of China, Yin Xiuqin, Zhu Tingcheng, Zhong Weiyan, Peng Wu Kui Jun 2024

Study Of The Diversity Of Soil Animal Community In The Songnen Plain Grassland Of China, Yin Xiuqin, Zhu Tingcheng, Zhong Weiyan, Peng Wu Kui

IGC Proceedings (1993-2023)

This paper makes a diversity study of 8 habitats of soil animal communities in Songnen plain grassland. The research shows that the better the habitat condition is, the higher the diversity index of soil animals, and the worse the habitat condition is the lower the diversity index of soil animals. The diversity of soil animal communities has a positive relationship with soil organic matter, total nitrogen, and has a negative relationship with pH value. It has no obvious relationship with soil water content and total phosphorus. The diversity of soil animal communities decreases with increasing depth of soil layer and …


Clipping Intensity Impacts On Root Mass Variation Of Cool Season Grasses, D L. Stetson, W M. Sullivan Jun 2024

Clipping Intensity Impacts On Root Mass Variation Of Cool Season Grasses, D L. Stetson, W M. Sullivan

IGC Proceedings (1993-2023)

Seasonal changes in grass root and mat weight density were documented under different cutting managements. Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) received one annual cut, twice yearly forage harvest, and mown turf treatments. Orchardgrass (Dactylis glomerata L.) received one annual and twice yearly cutting treatments. Soil cores were collected to a 15 cm depth and divided into 7.5 cm increments. Roots and mat were recovered, washed, dried and weighed. Differences in years, seasons, species, treatments, and soil depth significantly influenced total root weight density and fine root density. With all species and …


Effect Of Grazing And Soils On The Structure Of Mountain Vegetation Communities, I Alonso Jun 2024

Effect Of Grazing And Soils On The Structure Of Mountain Vegetation Communities, I Alonso

IGC Proceedings (1993-2023)

The range of life forms of four grassland communities in the Cantabrian mountains (N. Spain) was studied under grazing and when grazing was excluded in relation to soil characteristics. Hemicryptophytes were the most abundant life form in all communities and they increased their number when ungrazed. Diversity was bigger in the communities with shrubs, which presented a more heterogeneous structure. As a whole, grasslands on calcareous soils were more diverse than those on siliceous soils.


Increasing Grassland Biodiversity Within The Environmentally Sensitive Areas Scheme In The U.K, S Peel Jun 2024

Increasing Grassland Biodiversity Within The Environmentally Sensitive Areas Scheme In The U.K, S Peel

IGC Proceedings (1993-2023)

The ESA scheme is the main vehicle in the UK for increasing biodiversity on agricultural land. It is voluntary, and payments are made to compensate for reduced profitability when prescribed practices are followed. These include conversion of cropping land to grassland, zero fertiliser use and late cutting for hay. The scheme is supported by an R & D programme aimed particularly at practical problems arising from the need to reconcile environmental targets with the need to maintain viable and profitable livestock systems. The paper cites examples of this R & D, including choice of seeds mixtures, the role of soil …


Depression On The Hygrophytic Weed In Pasture Establishment With Consideration To Wildlife Habitat, T Sugiura, H Kobayashi Jun 2024

Depression On The Hygrophytic Weed In Pasture Establishment With Consideration To Wildlife Habitat, T Sugiura, H Kobayashi

IGC Proceedings (1993-2023)

We investigated the influences of lower ground water level on the hygrophytic weed which luxuriated at the abandoned paddy field as a pasture establishment method in wetland with consideration to wildlife habitat. In comparison with the control, the leaf of common reed (Phragmites communis Trin.) at the drainage area was decreased by the 60% in weight and distributed at lower layers due to water stress. The photosynthetic rate of the common reed was also decreased by 64%. At the end of the growing season, the botanical composition began to include more short type species.


Genetic Diversity In The Native Australian Grass Agrostis Adamsonii (Poaceae), E A. James, A Brown Jun 2024

Genetic Diversity In The Native Australian Grass Agrostis Adamsonii (Poaceae), E A. James, A Brown

IGC Proceedings (1993-2023)

Genetic variability in A.adamsonii is assessed from measurements of mature florets and from analysis of variation in DNA using the random amplified polymorphic DNA (RAPD) technique. Results are compared to those for three other species of Agrostis growing at the same site or in similar habitats.


Medicinal Plants As Indicators Of Grassland Biodiversity, G Nagy, I Vinczeffy, K Peto Jun 2024

Medicinal Plants As Indicators Of Grassland Biodiversity, G Nagy, I Vinczeffy, K Peto

IGC Proceedings (1993-2023)

A study has been made to identify the medicinal plants on the existing Hungarian grasslands. Sixty-three plants have been found to possess medicinal effects. Twenty-six, 15 and 22 species are for internal, internal or external and external use, respectively. This result reflects the low management intensity of grasslands in the country, as well as the species richness of semi-natural grasslands. It is suggested that the number of medical plants on the grassland, - in general - can also be used as an indicator of grassland biodiversity.


Sculpted Seeding: A Plant Community Approach To Revegitation, E T. Jacobson, D B. Wark, R G. Arnott, R J. Haas, D A. Tober Jun 2024

Sculpted Seeding: A Plant Community Approach To Revegitation, E T. Jacobson, D B. Wark, R G. Arnott, R J. Haas, D A. Tober

IGC Proceedings (1993-2023)

The sculptured seeding technique, an ecological approach to revegetation based on a knowledge and understanding of the natural vegetation of an area, establishes a diverse, effective native plant community capable of regeneration and plant succession. It is intended to match site capability with plant species known to thrive under particular conditions. Sculptured seeding is an option available to land managers interested in establishing and maintaining adapted native species and ecotypes within the limits of current technology and available seed sources. Field procedures for sculptured seedings are quite simple, involving only minor modifications to standard planting methodology. Seed mixtures based on …


Graded Management Intensity Of Grassland System For Enhancing Biodiversity On A Species And Landscape Scale, E Meister, B Koch Jun 2024

Graded Management Intensity Of Grassland System For Enhancing Biodiversity On A Species And Landscape Scale, E Meister, B Koch

IGC Proceedings (1993-2023)

The objective of our research is to maintain and enhance wildlife resources, landscape diversity and economic competitiveness of grassland-ruminant systems. This may be accomplished by a diversified, graded management intensity of pastures and meadows (Dietl,1990), resulting in a network of intensively and extensively used grassland and other semi-natural habitats. Botanical diversity is thus increased on both a habitat and landscape level. In intensively farmed regions it may be necessary to re-establish species-rich grassland types and adjust management intensity to the site conditions and species’ requirements.


Mineral Contents Of White Clover Grass And Nitrogen Fertilized Grass Pastures For Lambs, R Sormunen-Cristian, P Nykänen-Kurki, J Peltola Jun 2024

Mineral Contents Of White Clover Grass And Nitrogen Fertilized Grass Pastures For Lambs, R Sormunen-Cristian, P Nykänen-Kurki, J Peltola

IGC Proceedings (1993-2023)

The mineral contents (Ca, P, Mg, K, Na, Fe, Cu, Zn, and Mn) of white clover grass without nitrogen and grass-only pastures with annual nitrogen rates of 0, 120 and 250 kg ha-1 were studied in 1994 and 1995. The pastures were grazed twice per season by growing lambs. The white clover contents averaged 25% and 42%, respectively. The Ca and Mg contents and the Ca/P ratio were higher, and the K/(Ca+Mg) equivalent ratio lower in white clover grass than in grass-only swards. The P content of white clover grass was similar to that of grass, and the K content …


A Predictive Model Of Vegetation Dynamics Under Grazing, C.P. D. Birch, B R. Werkman, L W. Partridge Jun 2024

A Predictive Model Of Vegetation Dynamics Under Grazing, C.P. D. Birch, B R. Werkman, L W. Partridge

IGC Proceedings (1993-2023)

This quantitative model predicts changes in the species composition of grazed vegetation. It is based on growth equations for each species represented. The three parameters in each equation represent maximum production rate, maximum standing biomass, and the decline of production rate at high total plant density. Parameters may be varied with environmental factors. The model is generic, but is illustrated using values for four taxa growing under red deer (Cervus elaphus) grazing on the Isle of Rhum, Scotland: bent/fescue grassland (Agrostis/Festuca), purple moor-grass (Molinia caerulea), mat-grass (Nardus stricta) and heather (Calluna …


Integrating Satellite Images And Species-Based Vegetation Maps To Manage Native Grasslands, M Hall-Beyer, Q.H. J. Gwyn Jun 2024

Integrating Satellite Images And Species-Based Vegetation Maps To Manage Native Grasslands, M Hall-Beyer, Q.H. J. Gwyn

IGC Proceedings (1993-2023)

Satellite image mapping of grasslands is problematic when species diversity occurs at a sub-pixel scale. We propose a method, called melody classification, to map ground cover units that group several spectral classes (colours). Melodies are defined as the normalized expected frequencies of each class within the ground cover unit. Starting from an unsupervised classification, an image is created showing the probability of finding each spectral class in the vicinity of each pixel. Each pixel is classified by comparing the melody in its neighbourhood with that of each ground cover unit. Accuracies are greatly enhanced over those of supervised classification. Melody …


Collection And Evaluation Of The Section Platycarpe From The Peoples Republic Of China, T A. Cambell, G Bao, Z L. Xia Jun 2024

Collection And Evaluation Of The Section Platycarpe From The Peoples Republic Of China, T A. Cambell, G Bao, Z L. Xia

IGC Proceedings (1993-2023)

The Peoples Republic of China is the center of origin of several species of the section Platycarpae, which could contain genes for drought and cold tolerance that would be of significant benefit to cultivated alfalfa (Medicago sativa L.) Of particular interest are Medicago archiducis-nicolai Sirjaev, M. edgeworthii Sirjaev, and M. ruthenica (L.) Ledebour. Of 105 M. ruthenica accessions collected from 15 diverse environments in Inner Mongolia, 50 were evaluated in the field at Beltsville MD (USA) in 1993 and 1994 on an acid soil (pH 6.4) deficient in boron and potassium. Significant variation was noted for stand retention, reaction to …


Verification Of And Genetic Variation Between Stylosanthes Sp. Aff. S. Scabra Accessions, C J. Liu Jun 2024

Verification Of And Genetic Variation Between Stylosanthes Sp. Aff. S. Scabra Accessions, C J. Liu

IGC Proceedings (1993-2023)

Thirty-three Stylosanthes accessions, which are all considered to be S. sp. aff. S. scabra, were analysed using STS and RAPD as genetic markers. These accessions were readily clustered into two major groups based on dissimilarity values, with 28 accessions in one group (A) and the other five in the other (B). STS analysis indicated that accessions in group A are diploid S. sp. aff. S. scabra but those in B are tetraploids, likely to be S. scabra or its closely related taxa. Cytological examination of root-tip cells confirmed that the five accessions in group B are all tetraploids. Genetic dissimilarity …


Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak Jun 2024

Assessing The Impact Of Dietary Addition Of Lignin On Growth Performance, Nitrogen Balance And Faecal Microorganisms In Grain-Fed Veal Calves, L E. Phillip, E S. Idziak

IGC Proceedings (1993-2023)

A study was conducted with ALCELLR - lignin (A-lignin) to evaluate its impact on performance of grain- fed veal calves. Thirty two male calves (avg. initial wt, 190 kg) were fed for 13 weeks grain corn and a protein supplement with added A-lignin to supply 0, 1.25%, 2.5% or 5.0% of diet. Eight other calves were used to study nitrogen balance, and grab samples of faeces were analyzed for anaerobic, aerobic and coliform bacteria. A-lignin at 1.25% of diet increased (p<.01) weight gain by 12%. Addition of A-lignin also decreased (p< 0.01) organic matter digestion, increased (p<.01) faecal N excretion but did not significantly alter N balance. A-lignin reduced (p< 0.01) faecal ammonia concentration but increased (p <.01) DM content of grab samples of faeces; there were no significant effects on populations of faecal microorganisms. The study revealed a beneficial effect of A-lignin on calf growth but the reason for the response was not uncovered.


Qualitative Evaluation Of D.H.P. (Dihidroxipiridine) In The Urine Of Buffaloes Fed With Leucaena, P B. Alcantara, T A. Ferreira, D A. Beisman, A.M F. Pereira Jun 2024

Qualitative Evaluation Of D.H.P. (Dihidroxipiridine) In The Urine Of Buffaloes Fed With Leucaena, P B. Alcantara, T A. Ferreira, D A. Beisman, A.M F. Pereira

IGC Proceedings (1993-2023)

The aim of this study was to evaluate the DHP elimination in the urine of buffaloes fed with three levels of leucaena (0,10 and 20g of leucaena's DM/kg LW0.75), plus corn silage at 2.5% of LW in D.M. The main purpose was to estimate the levels of mimosine toxicity in those resistant animals. Data showed that DHP started to be eliminated at the first urination in both levels of leucaena. This occurred one hour after ingestion. DHP was present up to the third urination (5 hours after ingestion) in the highest level.


Genomic Cloning Of Fasciola Hepatica Excretory-Secretory Antigenic Genes In E. Coli, Xu Heng, Zheng Li, Liu Shigui, Shen Bin, Wu Fend Jun 2024

Genomic Cloning Of Fasciola Hepatica Excretory-Secretory Antigenic Genes In E. Coli, Xu Heng, Zheng Li, Liu Shigui, Shen Bin, Wu Fend

IGC Proceedings (1993-2023)

A complementary DNA (cDNA) library was constructed from the mRNA of adult worms of Fasciola hepatica in the expression vector gt11, the size of the library contained approximately 2.4 x 105 recombinants and the recombinant efficiency was 85%. The library was directedly screened with a rabbit antisera raised against a excretory-secretory (ES) antigen of Fasciola hepatica. Two positive clones of strong signal were selected from a group of 200 positive clones, named FH3 and FH7. The length of external fragments of two recombinants were 0.85Kb (FH3) and 1.15Kb (FH7). The E.coli 1089 host was infected by recombinants FH3 and FH7 …


Effect Of Plant Species On The Development And Vertical Migration Of Larvae Of Gastrointestinal Nematodes Which Parasitise Sheep, J H. Niezen, W.A. G. Charleston, J Hodgson, C M. Miller, H A. Robertson Jun 2024

Effect Of Plant Species On The Development And Vertical Migration Of Larvae Of Gastrointestinal Nematodes Which Parasitise Sheep, J H. Niezen, W.A. G. Charleston, J Hodgson, C M. Miller, H A. Robertson

IGC Proceedings (1993-2023)

The development and migration of gastrointestinal nematode larvae on a range of herbage species were compared following a series of standardised contaminations with sheep faeces over two years. In 1992/93, greatest numbers of larvae were recovered from browntop (Agrostis capillaris cv Grasslands Muster), cocksfoot (Dactylis glomerata cv Grasslands Kara), ryegrass (Lolium perenne cv Grasslands Nui) and Yorkshire fog (Holcus lanatus cv Massey Basyn) while the lowest numbers were recovered from white clover (Trifolium repens cv Grasslands Huia) with the other herbages intermediate. In 1993/94, highest numbers were recovered from Yorkshire fog and ryegrass, lowest numbers from …


Seed Proteinase Inhibitors From Annual Medics Active Against Insect Pests, M Odoardi, A Tava, F Ceciliani Jun 2024

Seed Proteinase Inhibitors From Annual Medics Active Against Insect Pests, M Odoardi, A Tava, F Ceciliani

IGC Proceedings (1993-2023)

Several different species of annual medics have been tested for the occurrence and concentration of trypsin inhibitors in the seed. Trypsin Inhibitory Activity (TIA) has been in fact related to the level of resistance to biotic and abiotic stresses. Wide variation was found for TIA among species, with the highest values shown by the snail medic (Medicago scutellata). After a simple and rapid procedure of chromatographic purification, the Trypsin Inhibitor (TI) from snail medic has been tested towards the trypsin-like proteinases extracted from larvae of different phytophagous insects, showing high levels of Inhibitory Activity. The complete amino acid …


The Effect On Intake Palatability And Digestibility Of Phenolic Compounds In Tagasaste (Chamaecytisus Proliferus), N J. Edwards, J C. Mailey, D M. Mcneill, J B. Lowry, C S. Mcsweeney, D A. Henry, C M. Oldham Jun 2024

The Effect On Intake Palatability And Digestibility Of Phenolic Compounds In Tagasaste (Chamaecytisus Proliferus), N J. Edwards, J C. Mailey, D M. Mcneill, J B. Lowry, C S. Mcsweeney, D A. Henry, C M. Oldham

IGC Proceedings (1993-2023)

The major secondary metabolites currently identified in tagasaste (Chamaecytisus proliferus) belong to the phenolic group of compounds. The principal phenolic compounds are the flavones, apigenin and luteolin, but low concentrations of condensed tannins, the isoflavonoid daidzein and the alkaloid sparteine have also been detected in some samples. No flavonols have been detected. There is a strong relationship between the concentration of phenolic compounds in tagasaste and its palatability. Furthermore, digestibility of tagasaste is relatively high throughout the year, thereby implicating intake as the major factor influencing the seasonality of liveweight performance of livestock grazing tagasaste. Despite confirmation of …


Effect Of Endophyte-Infected Tall Fescue Hay On Dairy Heifers Under European Intensive Management, J C. Emile, J P. Ravault, J M. Chabosseau Jun 2024

Effect Of Endophyte-Infected Tall Fescue Hay On Dairy Heifers Under European Intensive Management, J C. Emile, J P. Ravault, J M. Chabosseau

IGC Proceedings (1993-2023)

Two fields were established at Lusignan (France) with the same variety of tall fescue but differing in the rate of Acremonium coenophialum seed infestation : 0 % = E- ; 100 % = E+. Dairy heifers were fed ad libitum with E- or E+ hay and were given in addition 1.7 kg DM of concentrates. No effect was noticed on the intake (5.65 vs 5.63 kg DM) as well as on ADG (874 vs 838 g/d) regarding E- vs E+ hay resp. However, prolactin concentration was significantly halved when heifers were fed with the E+ hay. More temperate climatic conditions …


Feeding Strategies To Optimize Reproductive Performance Of Cattle Grazing High Protein Pastures In Uruguay, H R. Tosi, K M. Wittenberg Jun 2024

Feeding Strategies To Optimize Reproductive Performance Of Cattle Grazing High Protein Pastures In Uruguay, H R. Tosi, K M. Wittenberg

IGC Proceedings (1993-2023)

Alternative feeding strategies were investigated for Holstein heifers grazing a vegetative red, Trifolium pratense L., and white clover, Trifolium repens L., pasture. A total of 474 grazing heifers were supplemented varying amounts of corn silage, Zea mays, during the breeding season in an effort to improve reproductive performance. Animal response to supplementation, whether on spring or winter pasture, was similar. Corn silage supplemented at 18.8 or 28.8% DM basis of total diet, for winter and spring pastures, respectively, resulted in animal weight gains similar to that of heifers receiving legume pasture only. Serum urea nitrogen and reproductive performance for heifers …


Strategies For Improving Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, J C. Waller, H A. Fribourg Jun 2024

Strategies For Improving Efficiency Of Beef Cattle In Tall Fescue Pasture Systems, J C. Waller, H A. Fribourg

IGC Proceedings (1993-2023)

A beef (Bos taurusL.) cattle producer must allocate land and forage resources to meet nutrient needs of the entire herd. Using 20 yr of calving and grazing data, templates of herd composition, associated Total Digestible Nutrients (TDN) requirements over the whole year, and forage TDN production were developed for a typical herd and land area. The monthly energy needed by the entire herd was relatively constant. Forage productivity varied monthly, indicating the need to plan for efficiently using surplus TDN from some seasons to meet needs at other times. This approach could be expanded to include more definitive …


Eneficial Use Of Grasses Artificially Infected With Endophytes, Non-Toxic To Animals, G.C M. Latch, L R. Fletcher Jun 2024

Eneficial Use Of Grasses Artificially Infected With Endophytes, Non-Toxic To Animals, G.C M. Latch, L R. Fletcher

IGC Proceedings (1993-2023)

Information presented in this paper demonstrates that Ryegrass Staggers does not occur in animals which graze ryegrasses (Lolium sp.) artificially infected with a strain of Acremonium endophyte which does not produce the tremorgenic toxin lolitrem B. Peramine is produced by the endophyte and this alkaloid protects the grass from attack by Argentine stem weevil. New Zealand farmers have used a ryegrass cultivar infected with this strain of endophyte for the past four years and there are no reports of Ryegrass Staggers in animals grazing it. Strains of endophytes have been found in other grasses which do not produce toxins …


The Effect Of Ryegrass Endophyte On Milk Production From Dairy Cows In Northern New Zealand, E R. Thom, D A. Clark, C D. Waugh, R J. Mccabe, V T. Van Vught, B.J L. Kock Jun 2024

The Effect Of Ryegrass Endophyte On Milk Production From Dairy Cows In Northern New Zealand, E R. Thom, D A. Clark, C D. Waugh, R J. Mccabe, V T. Van Vught, B.J L. Kock

IGC Proceedings (1993-2023)

The aim of this study was to compare the milk production of cows grazing endophyte-infected perennial ryegrass (Lolium perenne L.) pasture with those grazing endophyte-free pastures. High and nil endophyte ryegrass pastures were drilled with and without white clover (Trifolium repens L.) in autumn 1993. White clover was completely removed in autumn 1995. High endophyte pastures had >85% of tillers infected but nil endophyte pastures were rapidly contaminated with endophyte-infected ryegrass and had 50% infection by autumn 1996. Losses in milk production due to endophyte were small (<6%), and occurred in only 2 of the 6 three week test periods. Cows showed clinical symptoms of ryegrass staggers in summer/autumn 1995 but not in 1996. Heat stress symptoms were absent. Losses of milk production occurred when lolitrem B levels were low (spring 1994) and when cows did not show clinical staggers (summer 1996). Other chemicals or agronomic factors could be important determinants of the milk production responses.


Use Of Willows (Salix Spp) As Drought Fodder For Sheep, S K. Oppong, P D. Kemp, G B. Douglas, B T. Bulloch Jun 2024

Use Of Willows (Salix Spp) As Drought Fodder For Sheep, S K. Oppong, P D. Kemp, G B. Douglas, B T. Bulloch

IGC Proceedings (1993-2023)

The effects of cutting height and harvesting times on the forage yield, yield components and quality of Tangoio hybrid willow and Kinuyanagi willow were examined, to evaluate these willows as drought fodder for sheep. Tangoio (3.8 tDM/ha) outyielded Kinuyanagi (3 tDM/ha) in edible forage production and provided reasonable quality fodder (nitrogen content of 2.0 % and digestibility of 65 -69 %). The high edible forage yield of the willows relative to pasture (0.8 tDM/ha) during January and April showed that they provided potentially valuable supplements to pasture production. The willows, especially Tangoio, are recommended for use as maintenance fodder for …