Plant Pathology Commons^™

Agronomic And Silage Quality Traits Of Winter Cereals, M K. Siefers, K K. Bolsen

IGC Proceedings (1977-2023)

Agronomic and silage quality traits were examined for 12 winter cereals harvested at two stages of maturity. Forage dry matter (DM) yields were higher at the mid-dough than the early-heading stage. Post 90 barley (Hordeum L.) had the highest whole-plant DM yield at the early-heading stage, and Presto triticale (X Triticosecale Wittmack) had the highest yield at the mid-dough stage. Newton wheat (Triticum aestivum L.) had the lowest whole-plant DM yield at both stages of maturity. Both crude protein (CP) and ash contents were higher for the early-heading than the mid-dough cereals. All 24 silages were of relatively …

Estimating Forage Quality Losses During Field Drying, D M. Brown, A G. Barr, D M. Smith

IGC Proceedings (1977-2023)

The objective of this study was to determine how well changes in forage quality could be simulated during field drying for hay. Measurements of moisture content and three quality components were made during eight drying periods over three years. Samples were taken from forage swaths at one to four day intervals during drying period. Changes in total dry matter and its constituents were calculated from the measured/simulated changes in quality components. Comparison of simulated and measured changes were made for total losses and cumulative changes during each drying period. The simulated total dry matter losses were within the error limits …

Mineral Intake And Utilization By Dairy Cows Offered Grass Fertilized With Different Levels Of Nitrogen, H Valk, A M. Van Vuuren

IGC Proceedings (1977-2023)

In four zero-grazing experiments, the effects ofN fertilizer (450 to 300 to 150 kg/ha/yr) on intake and utilization of some grass minerals (Ca, P and Mg), were investigated. Grass was offered ad lib to 12 cows per N treatment. A reduction in N fertilizer resulted in lower mean contents and intakes of Ca and Mg while P content and intake increased in late summer/autumn. The output of these minerals in milk and urine was relatively low. Therefore, a reduced intake of Ca and Mg resulted in a lower faecal output of these minerals. The ratio between intake and requirement varied …

Performance Of Grazing Bull Calves Supplemented With Increasing Levels Of Ruminally Undegradable Portein, J R. Kawas, O Osmin, J Hernandez, R Leal, F Garza, J L. Danelon

IGC Proceedings (1977-2023)

The objective of this study was to determine the effect of increasing levels of ruminally undegradable protein (ECP) on the performance of bull calves grazing Coastcross-1 Bermudagrass during the dry season. One hundred and twelve Zebu-Brown Swiss bull calves weighing an average of 265 kg, were randomly assigned to four treatment groups in a completely random design. Calves received a self-feeding supplement (1 kg) with 40% crude protein (CP) and 31, 38, 44, or 52% ECP. During a 96-day preliminary phase without supplementation, weight gains of the four treatment groups ranged from 0.357 to 0.394 kg/day. A linear (P<0.0 I) response of calf weight gain was observed with an increase in ECP of the supplement (0.668, 0.672, 0.823 and 0.893 kg/day, respectively). Plasma urea concentration was reduced (P<0.05) from 17.8 to 9.85 mg/di with the highest level ofECP, which may reflect a reduced supply of NH -N for ruminal bacteria.

Relationships Between Rumen Degradability And Cell Wall- Binding Ferulic Acid Ethers In Various Forage Crops, M Goto

IGC Proceedings (1977-2023)

Ether-linked ferulic acid was determined in whole straw, plant parts and specific tissue cell walls of five barley (Hordium vulgare L.) cultivars and in sorghum stalks (Sorghum bicolor Moench x Sorghum sudanense Stapf) with five different growth and maturation stages and was related to their dry matter degradability (DMD) and extent of alkali-labile substitution at 0-5 arabinose residues previously determined.

The Energetic Utilization Of Forages In Fresh And Dried Condition By Ruminants, W Jentsch

IGC Proceedings (1977-2023)

The influence of dehydration of forages on digestibility and energy utilization was measured by indirect calorimetry in respiration chambers with adult wether sheep as a model for ruminants. Comparisons were carried out between fresh and carefully dried forages (experiment 1) and between fresh and not only carefully but also severely dried forages (experiment 2). Careful drying caused no change, but severe drying decreased energy and especially crude protein digestibility. There were no differences in utilization of metabolizable energy between fresh and carefully or severely dried forages.

Effect Of Variation In The Quality Of Forage Maize Silage In Ireland On Forage Intake And On Milk Production Of Dairy Cows, J J. Fitzgeald

IGC Proceedings (1977-2023)

In three experiments maize silages which varied in quality, i.e. starch content and dry matter digestibility (DMD) replaced a high proportion (60-67%) of grass silage in the diet of cows in early or mid-lactation. In each experiment the forages were supplemented with concentrates (4 or 6 kg/cow/day). Replacing high quality grass silages (DMD 750 g/kg) with high quality maize silages (starch 219 or 355 g/kg DM, DMD 694 or 754 g/kg) significantly increased forage intake, milk yield, milk protein concentration and the yield of fat and protein (Experiments 1 and 3). Replacing grass silage with a low starch maize silage …

Minerals In Forages Of Southern Italy Relate To Climate And Harvest Time Effects, G Convertini, D Ferri

IGC Proceedings (1977-2023)

Three cultivars of Alfalfa (Ascolana, Bresaola L 202 and Canè) in the Apulian “Tavoliere” (southern Italy) environment were studied. The effects of three water levels (watering of 1000 m3 ha-1 after each cut; 500 m3 ha-1 as above and another water supply with the same volume when the plant reached wilting conditions; with watering of 300 m3 ha-1 every 8 days to assure continuous water availability) and two cutting times (flower bud and 50% of flowering) were investigated. The cultivars showed a different mineral composition only for quantities not for qualities. The mineral composition of three cultivars were similarly influenced …

Foliar Supplementation Of Minerals To Prevent Calcium And Magnesium Deficiencies In Dairy Cows, G F. Wilson, W J. Courtney

IGC Proceedings (1977-2023)

The objectives of this study were to examine the possibility of reducing the incidence of calcium and magnesium deficiencies in cows by feeding anionic salts and by manipulating the mineral concentrations in pastures with foliar sprays during late pregnancy. Cows provided with a mineral supplement of magnesium chloride and ammonium sulphate before calving produced more milk solids and experienced less health problems. The foliar application of anionic salts, with and without sodium chloride, altered the cation balance in pastures grown on 6 different soils.

Genetic Variation In Perennial Ryegrass For Volatile Fatty Acid Production In Rumen Fluid, H.J P. Marvin, E N. Van Loo, O Dolstra, C.H A. Snijders, D Reheul, J W. Cone

IGC Proceedings (1977-2023)

In perennial ryegrass genetic variation was shown not only for in vitro organic matter degradation (OMD) in rumen fluid and neutral detergent fibre content (NDF) but also for production of volatile fatty acids (VFAs) upon in vitro incubation in rumen fluid. The correlations among concentrations of VFAs in the incubation fluid were high. OMD and NDF, on the other hand, were poorly correlated to the VFA concentrations.

Characterization Of Legume And Grass Residues Following In Vitro And In Sacco Ruminal Digestion, D.J R. Cherney, J H. Cherney, A H. Davidson

IGC Proceedings (1977-2023)

Objectives were to characterize the influence of forage species and maturity on dry matter degradation. Averaged across maturities, alfalfa and red clover were lower in NDF content (39 and 30% NDF, respectively) than reed canarygrass and timothy (59 and 54% NDF, respectively). The NDF of the DM residues in grass remained relatively unchanged over time, while NDF of the DM residue in legume increased rapidly for 9 h before becoming relatively constant. Alfalfa incubated in vitro (42% NDF) compared to reed canarygrass (58% NDF) contained more ND soluble material (39% vs. 25%), and more pepsin soluble material (22 vs. 18%). …

Potassium Accumulation In Perennial Cool-Season Grass Forage, J H. Cherney, D.J R. Cherney

IGC Proceedings (1977-2023)

Perennial grasses are well adapted to the northern U.S.A. and Canada, but the potassium (K) content of grass forage is a major concern in regard to dairy cattle nutrition. Our goal was to identify factors influencing potassium content of grasses, so that a grass management strategy for controlling potassium content could be formulated. Separate experiments were conducted with several perennial coolseason grass species and varieties. Nitrogen fertilization and harvest management also were evaluated. Aside from the obvious positive effect on K concentration caused by commercial K fertilizer or by animal manure application, K concentration was influenced by grass species, grass …

Influence Of Different Cutting Frequencies And Fertilization On Grass Silage Quality, U Wyss, R Vogel

IGC Proceedings (1977-2023)

The influence of different cutting frequencies and fertilization on dry matter yield, botanical composition, nutrient concentration and fermentation quality of grass silage was investigated. Altogether four treatments were compared; two 5-cut-treatnents with two different fertilizer levels, one 3-cut-treatment with fertilizer and one 2-cuttreatment without fertilizer. In the 5-cut-treatments the double fertilizer amount produced a 10% higher dry matter yield and also a higher proportion of grasses. The fermentation quality of these silages was mostly good, especially in autumn when the high nitrate content improved the quality. The 3- cut and 2-cut-variants showed a higher grass proportion, a higher crude fibre …

Seasonal Changes In Forage Quality Of C3 Grasses On Sagebrush Grassland, H F. Mayland, G E. Shewmaker

IGC Proceedings (1977-2023)

Annual and perennial grasses growing in the semiarid, west-central North American continent mature by early to midsummer. Forage mineral concentrations in these C-3 grasses decrease curvilinearly as the season advances from day of year (DOY) 75 to 300. Total digestible dry matter (TDDM) and digestible cell wall (DCW) decrease linearly with DOY while neutral detergent fiber (NDF) increases curvilinearly. By midsummer; energy, N, P, and Zn usually become deficient for ruminant nutrition.

Nitrogen Fertilizer Effects Upon Silage Composition And Quality Of Lolium Multiflorum, L., E M. Viviani Rossi, L M. Gutierrez, E Moreno, A Mazzanti

IGC Proceedings (1977-2023)

The objective of this study was to determine the ensiling properties of ryegrass (Lolium multiflorum L) fertilized with different doses of nitrogen. A pure ryegrass pasture was sown in March 1994 and six N doses (0, 50, 100, 150, 200 and 250 kg N.ha-1) were applied in August 1994. The lots were harvested 60 days after fertilization. The harvested material was chopped and stored for about 60 days in 5 l Polyvinyl chloride (PVC) laboratory silos, and replicated 3 times. Values of DM, IVDMD, TN, NDF, WSC, pH, NH3-N and Sol-N were determined. A completely randomized design was applied, …

Protein Degradability Effect And Supplementation Level On Pasture Utilization, A.V M. Franco, P De Andrade, G L. Franco

IGC Proceedings (1977-2023)

The objective was to determine the effect of protein degradability and supplement level on forage degradation. Steers fistulated were utilizated in brachiaria (Brachiaria brizantha) pasture. A randomized block design was used with a control treatment and supplements according to a factorial scheme combining low, medium and high protein degradability with supplementation levels: low, medium and high analysed as principal treatments and incubation time as splitplot by SAS. Nylon bags were incubated at 4; 8; 12; 24; 48; 72; 96 and 120 hours to determine DM, CP and NDF degradation. There was no effect (P>0.05) of protein degradability …

Breeding To Improve Yield And Quality In Napiergrass, Y K. Cheng, C S. Chen

IGC Proceedings (1977-2023)

The breeding program has been conducted to improve the production and quality of napiergrass by crossing with related species or intraspecies. CV. TLG2 with high yields and water soluble carbohydrates have been selected and released. It produced 20% more forage yields and water soluble carbohydrates than cultivar, CV. A146 and persisted well at least for five years. Good silage was obtained when the CV. TLG2 was harvested at the right time. Milking ability is improved by use of silage and/or green chopping whole year round.

Use Of Nir To Estimate Nitrogen Degradability Of Forage, R Agneeseens, P Dardenne, Ph Lecomte

IGC Proceedings (1977-2023)

Near infra red spectrometry (NIRS) is commonly used to characterise animal feeds at the level of their intrinsic composition (dry matter, protein, fat, fiber) as well of their digestibility (Dardenne et al.,1991). The use of new systems in the evaluation of the protein value has induced the necessity to determine parameters such as the theoretical ruminal degradability of nitrogen (DT).

The definition of this criterion necessitates the implementation of the nylon bag technique which is time consuming and costly and is reserved to reference laboratories. An alternative to this technique, based on an enzymatic hydrolysis of the proteinic content, has …

Energetic Feed Value Of Grassland Products In Ruminants, A Chudy

IGC Proceedings (1977-2023)

A method for calculating the energetic feed value, based on the digestible nutrients and on the relations of the utilisation of the energy of the nutrients (carbohydrates = 100) for ATP syntheses is described. This relative scale is a nominal feed value (NFV). It characterises the ATP potential of the feedstuffs and is therefore equivalent to the efficiency of utilisation of the feed energy in the catabolic metabolism (non-thermal maintenance, muscular work (movement)) and energy costs for syntheses as well as the productive performance as energy retention in animal products. Therefore this scale secures a precise precognition of the animal …

Forage Productivity Evaluation And Geographic Information Systems In Temperate Semi-Arid Agro-Ecosystem, H Salinas, R Ramirez, J Zegbe, G Medina, R A. Martinez

IGC Proceedings (1977-2023)

700,000 ha of the temperate semi-arid area of Zacatecas state are grown with rainfed crops. Low productivity is obtained from these crops: 350 kg/ha of beans grain and 500 kg/ha of corn grain. This state is characterized by a wide range of topographic and climatic values. A need for alternative crops led to establishment of a trial to evaluate rainfed forages, and to know in what range these could be located. Geographic information systems were used to find out the potential area of the species. Results indicated that sorghum presented a higher yield (5822 kgDM/ha) than sorghum x sudan (5460), …