Weed Science Commons^™

Adoption Of Leucaena For Cattle Grazing In Australia, J H. Wildin

IGC Proceedings (1977-2023)

The tree legume Leucaena leucocephala is a high-quality cattle forage in many tropical countries. For the past 30 years, cat­tlemen have not planted leucaena despite conclusive evidence from small grazing experiments that it improved beef production and was suited to a large area of northern Australia. Seed of four cultivars was available in the 1960s. In 1968 cv. Peru, an ex­ cellent forage type, was planted in a 24-ha block specifically for seed production. But little of this seed was used in Australia. There were sev.eral probable reasons for the nonadoption of leucaena. Adverse publicity on the extreme effects of …

Advances In Pasture Research And Development In Santa Cruz, Bolivia, R T. Paterson, C R. Horrell

IGC Proceedings (1977-2023)

Cattle production is important in Santa Cruz but is low in productivity, due in part to low grazing value of natural pastures, particularly in the dry season. Other constraints to cattle production include low land values, poor management, high cost of in­puts, and relatively low product prices. This program is aimed at providing higher-quality, low-cost pastures for complemen­tary use within traditional grazing systems. Improved introduced species were identified for five agro-ecological zones, and commercial seed production of the following was encouraged: Petri guineagrass (Panicum maximum), Brachiaria decumbens, buf­felgrass (Cenchrus ciliaris), glycine (Neonotonia wightii, formerly Grycine wightii), Archer axillaris (Macroryloma axillare), …

Effect Of Sheep And Cattle Grazing On A Mixed Pasture Of Perennial Ryegrass, Kikuyu, And White Clover, G J. Goold

IGC Proceedings (1977-2023)

Mixed pastlkes of perennial ryegrass (Lolium perenne L. ), kikuyugrass (Pennisetum clandestinum Hochst. ), and white clover (Trifolium repens L.) are commonly found within warm-zone areas of New Zealand but are frequently disliked because of prob­lems associated with kikuyugrass dominance. A grazing experiment was conducted to provide basic information on the response of such swards to grazing by cattle and sheep. The pastures were rotationally grazed with young sheep or cattle at two stocking levels each year from 1970 to 1975, with stocking rates adjusted twice yearly according to seasonal pasture growth. The pastures grazed by cattle …

Influence Of Sward Structure Upon Herbage Intake Of Cattle Grazing A Perennial Ryegrass Sward, M H. Wade, Y.L P. Le Du

IGC Proceedings (1977-2023)

To examine the influence of structural distribution of herbage within a sward on intake by grazing animals, two swards of contrasting structure were established at two periods in the grazing season by either infrequent mowing (C) or hard sheep graz­ing (G) of a perennial ryegrass (Lolium perenne) pasture. The plots were then allowed to grow undisturbed for about 5 weeks before being grazed by young cattle for periods of 2 weeks at two levels of herbage allowance, 30 and 60 g dry matter/kg live weight/day, in July (1) and in September (2). Detailed measurements of sward structure were …

Use Of Principal-Component Analysis In Summarizing Nutritive And Analytical Characteristics Of Forages, O T. Stallcup, C J. Brown, Z B. Johnson, D L. Kreider, J O. York

IGC Proceedings (1977-2023)

Principal component analysis and other multivariate analyses have not been used extensively to analyze forage data. Our objective was the synthesis and summary of 98 digestion trials on forages using a principal-component analysis. The ten variables studied in all trials were dry matter (DM), crude protein (CP), digestible protein (DP), crude fiber (CF), ether extract (EE), nitrogen-free extract (NFE), ash (A), gross energy (GE), total digestible nutrients (TDN), and digestible energy (DE). Acid detergent fiber (ADF), acid detergent lignin (ADL), and cellulose (C) were summarized, in addition, for some forages. When data on thirteen variables in 24 hays were summarized, …

Nutritive Value Of Cattle Diets On Fertilized And Unfertilized Blue Grama Rangeland, J D. Wallace, F J. Cordova, G B. Donart, R D. Pieper

IGC Proceedings (1977-2023)

Low levels of nitrogen (N) fertilization can substantia1ly increase forage production on native rangeland if adequate precipita­tion is available. The objective of this study was to_ compare nutritive value of diets selected by Hereford steers grazing unfer­tilized and N-fertilized (45 kg N/ha) rangeland in south central New Mexico. The study area consisted of two adjacent pastures of approximately 60 ha each, containing comparable areas ofbottomland, upland, and hillside sites. Stocking rates were 4.8 and 2.4 ha/yearling steer for control and N-fertilized pastures, respectively. Dietary samples were collected from esophageally fistulated steers (average weight 308 kg) during early, middle, and late …

Diet Selection By Cattle On Tropical Pastures In Northern Australia, B Walker, M T. Rutherford, P C. Whiteman

IGC Proceedings (1977-2023)

Diet selection by steers in northern Australia on a continuously grazed pasture of Setaria sphacelata var. sericea (Kazungula), Macroptilium atropurpureum (siratro), and Stylosanthes guianensis var. guianensis (Schofield) was studied. The pasture treatment that supported the highest annual weight gains (254 kg/steer) in a stocking-rate experiment had 1.7 steers/ha. Mean annual rain-fall was 1,490 mm, with 70 % falling from December to March. Monthly average temperatures are highest in December (30 .1 °C) and lowest in July (11. 9°C). Pastures were sampled in 1973 (seven 3-day periods) and 1975-1976 (six 3-day periods) with three esophageal fistulated steers. Extrusa samples were analyzed …

Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo

IGC Proceedings (1977-2023)

Measurable energy storage on grassland ecosystems was examined for 5 years at the Fujinita site under the same rotation pro­gram with two grazing intensities. Daily global solar radiation and photosynthetic active radiation were measured as the energy sources in the ecosystem. Primary production by pasture plants and amount grazed by cattle were estimated by the biomass dif­ferences inside and outside of protection cages. For the estimation of energy produced or stored by plants or cattle, calorific values were examined for dominant plant species at the Fujinita site. Seasonal changes in digestibility were investigated to ascertain the energy of herbage digested …

Evolution Of Selection Techniques In Breeding For Bloat-Safe Alfalfa, B P. Goplen, R E. Howarth, G L. Lees, W Majak, J P. Fay, K J. Cheng

IGC Proceedings (1977-2023)

This report summarizes the Canadian breeding program to develop a bloat-safe alfalfa (Medicago sativa L.). This program has experienced an evolution of selection methods in attempting to identify bloat-safe alfalfa genotypes. In chronological order, the methods involved selection for fraction I (18S) protein, soluble proteins, foam volume, tannins (flavolans), saponins, initial rate of digestion (IRD), sonication, purified enzymes, gas production, and leaching. Although soluble herbage protein is correlated with the occurrence of pasture bloat, we have experienced slow progress in a selection program to reduce soluble-protein concentration in alfalfa. We have found that foam volume is not correlated with …

Leucaena - A Permanent Dry Season Forage In Australia, J H. Wildin

IGC Proceedings (1977-2023)

Leucaena (Leucaena Jeucocephala) can play an important role in alleviating the general low pasture quality during the dry season. Extensive commercial use of leucaena for cattle grazing commenced in central Queensland in 1980 when the grazing management of this tree legume was modified to suit Australian beef producers. Plantings increased from 30 ha in 1979 to 3000 ha in central Queensland by February 1985. This rapid expansion can be attributed to beef producers being more aware ofleucaena management and benefits based on several commercial successes. Mimosine toxicity has not been a problem when cattle have access to tree …

Forest Grazing In Taiwan, M D. Huang, K J. Chen, Y J. Wu, J C. Yang

IGC Proceedings (1977-2023)

Due to the shortage of man-power in rural regions, forest grazing was tested as an alternative to eliminate the noxious plants dispersed on the timber plantations in Taiwan. Tree growth was not affected, when Hereford heifers were introduced to 4-year-old Taiwania cryptomerioides plantations(at 1,600 m altitude). Although indigenous water buffaloes were less tolerant to heat than the European cattle( Hereford and Holstein), they were able to show moderate body weight gain in the tough forest environment. Partial blood profiles obtained from buffaloes and cattle gave the same conclusion.

Effects Of Fluidized Bed Combustion Residue Application To Reclaimed Mine Land On Yield And Composition Of Forage And Performance Of Grazing Steers, K O. Smedley, J P. Fontenot, V G. Allen, H D. Perry, O L. Bennett

IGC Proceedings (1977-2023)

Fluidized bed combustion residue (FBCR), a waste product resulting from the addition of limestone to coal prior to combustion, is high in sulfur (S) and has approximately 50% of the neutralizing capacity of limestone. Research was conducted to study effects of repeated applications of FBCR to pastures on forage yield and composition, and on performance and health of grazing cattle. Three treatments were applied in three replicated .81 ha pastures located on acidic reclaimed land which had been previously mined by mountain top removal. Treatments were control, dolomitic limestone (3380 kg/ha) and FBCR (6760 kg/ha), applied in split applications. Pastures …

The Effect Of The Species, Stage Of Maturity And Level Of Intake Of Grass On The Efficiency Of Microbial Protein Synthesis In The Rumen Of Cattle, F J. Hart, Jane Leibholz

IGC Proceedings (1977-2023)

This study was undertaken because there is a paucity of information in the literature on the efficiency of microbial protein synthesis in the rumen of cattle when grass is fed as the sole diet. There is also little experimental data available on the factors which affect the efficiency of microbial protein synthesis. The work involved feeding six rumen fistulated Friesian steers with three species of grass which were harvested at various tages of maturity. In addition each maturity of forage was fed at three 15levels of orp5 nic matter ( OM) intake.

as sampled at the omasum and microbial protein …

Mixed Animal Species Grazing Under Temperate And Semi-Arid Conditions, T Nolan, J Connolly, L M. Guillon, C Sall, K Dieye, K Dieye, H Guerin

IGC Proceedings (1977-2023)

Mixed grazing has been practiced for a long time, under a variety of climatic conditions, combinations of animal species and grazing managements (Nolan and Connolly, 1977). They suggested that although mixed grazing research progress was impeded by difficulties associated with the increased number of variables involved it offered greater opportunity to improve resource use. The purpose of this paper is to present results from recent research carried out under temperate and semi-arid conditions related to individual animal and per unit area outputs, animal/vegetation relationships and complemetary patterns of grazing behavious in relation to more efficient and balanced use of vegetation …

Legume Pasture Units For Supplementing Cattle Grazing Rangeland Under Traditional Production Systems In The Nigerian Subhumid Zone, R.R Von Kaufmann, M.A Mohamed Saleem

IGC Proceedings (1977-2023)

The subhumid zone occupies approximately 20 % of West Africa and 50 % percent of Nigeria, subsaharan Africa's most populous country. It is characterised by receiv��ng between 900 and 1500 mm of annual precipitation and havmg between 170 and 280 growing days per annum. Although the zone h��s high agricultural potential it has been avoided by both c1;1ltiva!ors and pastoralists until recently mainly due to po��r s01l f��rtlhty and the endemic cattle disease, tryponosormas1s, earned by tsetse flies. Now increasing settlement of people is leading to ecological changes that are permitting the perma��en�� residei:ce of ruminant livestock. Clearing ofland for …

Effect Of Repeated Applications Of Fluidized Bed Combustion Residue To Reclaimed Surface Mined Pastures, M A. Cochran, J P. Fontenot, H D. Perry, V G. Allen

IGC Proceedings (1977-2023)

Reclaimed surface mined land is potentially valuable for use as pasture, but its low fertility limits its use without soil amend­ment (Armiger et al., 1976). The usual acidic nature of these soils may result in mineral deficiencies and toxicities in forage (Vogel, 1981). Fluidized bed combustion residue (FBCR) is the residue from combustion of coal with limestone mixed in a jet air stream in coal-burning power plants (Fennelly, 1984). The procedure is used to trap pollutants such as sulfur dioxide, nitrogen oxides, and volatile elements that would normally be emitted into the atmosphere. The FBCR retains about 50 % of …

Near Infrared Reflectance Spectroscopy For Estimation Of Digestible Organic Matter Intake And Body Weight Gain, H Lippke, F E. Barton Ii, W R. Ocumpaugh

IGC Proceedings (1977-2023)

High correlations have been reported between data from near infrared reflectance spectroscopy (NIRS) and the protein and fiber contents, as well as the intake and digestibility, of forages (Norris et al., 1976). The finding in some studies that sample sets for calibration and unknown samples should be restricted to relatively narrow populations (Marten et al., 1983) has limited the usefulness of NIRS. However, in experiments with legumes, correlations with NIRS data were almost as good across species as among species (Marten et al., 1984). The experiment reported here was conducted to discover quantitative relationships between NIRS spectra and chemical composition, …

Integration Of Wildlife And Cattle On Communal Lands In Kangwane, South Africa, M Stalmans, A Van Wyk, M T. Mentis

IGC Proceedings (1977-2023)

The feasibility of integrating wildlife with the current livestock husbandry on communal lands in KaNgwane was investigated. Present stocking rates were 3 times the recommended figure for production farming. This fitted predictions based on the Jones-Sandland model for populations where the major consideration is maximum number of animals rather than high productivity. The integration of game was seen as a means to increase economic output, while spreading benefits from the use of natural resources to the community at large and establishing a form of ecologically sustainable land use. The active involvement of the community in the planning process and their …

Cattle And Wildlife Ranching In The Zimbabwe Midlands: Are They Economically Compatible?, Urs P. Kreuter, John P. Workman

IGC Proceedings (1977-2023)

Thirty-five Midlands ranches earning revenue from beef caltle, wildlife, or both during 1989-90 were surveyed to determine their financial and economic· profitability. Market prices were used to calculate financial profit, and opportunity costs were used to estimate economic profit of each operation. Under current market conditions, only mixed ranches produced positive financial profits, Economic profits were significantly higher than financial profits for all three types of operation. This implies that they all faced production disincentives due to government policy interventions. However, there were no significant differences between the economic profits of the three types of operations and none of them …

Major Beef Production Gains From Commercial Rain-Fed Leucaena-Grass Pastures In Central Queensland, Australia, J H. Wildin

IGC Proceedings (1977-2023)

Commercial leucnena-grass pastures in central Queensland increased from 24 ha in 1979 to about 20 000 ha in 1992. Since 1986 the exotic leucaena psyllid devastated leucaena (Leucaena leucocepliala) production along the humid coastal areas but not in the subcoastal plantings where the hot dry atmosphere controls the psyllid populations. The introduced rumen bacteria to detoxify DHP has enhanced the performance of cattle grazing leucaena. Unfertilised rain-fed leucaena-grass pastutes with leucaena rows 5-10 m apart have given annual steer live-weight gains of more than 250 kg consistently at stocking rates around 1-1.5 ha/steer. One cattleman with about 500 …

Mixed-Species Grazing In The Highland Sourveld Of South Africa: An Evaluation Of Animal Production Potential, M B. Hardy, N M. Tainton

IGC Proceedings (1977-2023)

The effects of mixed-species grazing, at 5 cattle to sheep ratios all at the same stocking rale, on individual animal mass change/ ha mass change/ Ila were monitored for 2 grazing seasons, The ratios were balanced in terms of animal units which equate the expected intake of cattle and sheep. The study was conducted on a humid grasslands in which the herbage characteristically loses quality as Jt mature1. Mass gains of individual cattle were higher when the cattle grazed 10ge1her with the sheep than when they grazed alone. This was ascribed to increasing herbage availability as the ratio of cattle …

Evaluation Of Brachiaria Decumbens And Brachiaria Brizantha Under Grazing, V.P B. Euclides, A H. Zimmer, M P. Oliveria

IGC Proceedings (1977-2023)

A 3-year grazing trial was conducted in Brazil, to relate changes in sward characteristics of B. decumbens and B. brizantha to animal live-weight gain (LWG). Three 1.5-ha paddocks of each grass species were stocked continuously with 3 steers, and additional grazers were added or removed as required to ensure similar grazing pressure in each treatment. Despite similar (P>0.85) annual average daily gains (ADO) of steers grazing both species, the ADO of steers grazing B. brizantha pasture was significantly (P<0.05) higher during the wet season, and significantly (P<0.05) lower in the dry period, when compared with those on B. decumbens. Annual LWG per area of both species were also similar (P>0.85). The best predictor of ADO was …

Effects Of Grain Supplement For Steers Grazing Stargrass Pastures On Subsequent Feedlot Gains And Carcass Characteristics, G.M.J Horton, W D. Pitman, E M. Hodges

IGC Proceedings (1977-2023)

Performance of steers (181 kg) grazing slargrass pastures was evaluated al 2 levels of grain supplementation in comparison with unsupplemenled cattle and with steers in drylot fed a high-roughage diet. Supplements during the 140-day winter period were fed at 1.0 (moderate) and 1.5% body weight (BW)lday (high), followed by 0.40 kg (moderate) and 0.5% BW/day (high) during the 98-day spring grazing period. Gains during a subsequent 100-dny, high-energy feeding period and resulting carcass characteristics were also compared. Gains during !he grazing period did not differ between !he 2 levels of supplement. Daily rate of gain of unsupplemented cattle (0.44 kg) …

Cattle Growth And Diet Responses To Legume And Phosphorus Supply, C P. Miller, R E. Hendricksen

IGC Proceedings (1977-2023)

Phosphorus was supplied to oversown pastures and steers grazing them, as supplement or as 3 rates of fertiliser over 2 years. Dry­season live-weight change was related to fertiliser rate and legume availability, with live-weight losses on unfertilised pastures, gains on moderately fertilised pasture and maintenance on low-fertilised pasture. Supplement had no effect. Wet-season live-weight gain was increased through fertiliser effects on legume availability and consumption (total response was 42 kg/steer) and through P supplement effects on phosphorus intake (total response was 34 kg/ steer). These and related studies have allowed rational and economical P management of oversown pasture systems in …

Increasing Cool-Season Production From Irrigated Leucaena Leucocephala, D Pratchett, S Petty

IGC Proceedings (1977-2023)

Annual live-weight gains of cattle grazing irrigated Leucaena leucocephala in the ORIA (Ord River Irrigation Area) average 0.7 5 kg/day al a stocking rate of 7.5 animals/ha. During the dry season the cooler temperatures reduce the growth rate of leucaena and live­weight gains are reduced lo about 0.5 kg/day. To date growth rates have been maintained by reducing stocking rates but a continuous supply of stock is now required to meet the demands of a local abattoir in the ORIA. During the cooler period a supplement of 1.5 kg maize/animal/day plus hay increased the live-weight gain of cattle to 0.75 …

Winter Grazing Rough Fescue Grasslands With And Without Preconditioning On Annual Pasture, W D. Willms, L M. Rode, B S. Freeze

IGC Proceedings (1977-2023)

Winter grazing of the fescue prairie is desirable to reduce the cost of feeding preserved forages and to conserving the native prairie. Rough fescue (Festuca campestris Rydb,), the dominant and most productive forage species in the foothills region, is highly sensitive to summer grazing but tolerates grazing while dormant. Since the forage quality declines after senescence, and the energy requirements increase in winter, this study was made to determine the feasibility of winter gmzing pregnant Hereford cows with and without preconditioning on annual pasture. The study, replicated over a 4-year period {n=4), used a 2x2 factorial design representing native …

Breeding To Reduce Susceptibility To Bloat In Dairy Cattle, C A. Morris, R J. Wilkins

IGC Proceedings (1977-2023)

An experiment with Friesian x Jersey cross cattle was established in 1972 at Ruakura, in order to select in 2 closed herds for high (HS) or low (LS) susceptibility to pasture bloat. By the 1990 calf crop, there was a difference in adjusted bloat score between herds of 0.94 units (1.93 genetic standard deviations). The repeatability and heritability of a single bloat score were 0.13+0.02, and 0.12+0.06, with a heritability of 0.52+0.22 for mean bloat score. Annual death rates from bloat have averaged 2.6% in the HS herd and 0.8% in the LS herd (0% in the LS herd for …

Effect Of Tiller Endophyte Infection Frequency And Nitrogen Fertilizer Rate Of Tall Fescue On Steer Performance Over Nine Seasons Of Grazing, J A. Stuedemann, S R. Wilkinson, D P. Belesky, F N. Thompson, D L. Breedlove, D M. Hildreth, H Ciordia, A H. Parks, C S. Hoveland, J Huang

IGC Proceedings (1977-2023)

Acremonium coenopliialium-infected tall fescue (Festuca arrundinacea Schreb.) is associated with animal health problems including reduced ,veight gains. Twelve 0.7 ha paddocks were used to study Kentucky- 31 tall fescue at low (LE=25%) or high (HE::58%) tiller endophyte (E) infection frequencies and fertilised with either 134 (LN) or 336, kg nitrogen/ha/year (HN) in a 22 factorial arrangement of treatments. Yearling Angus steers grazed under put-and-take management from April or May through late July or early August in each of nine years. In all except one year, ADG was lower (P<0.0769 to P<0.0018) on HE than LE. In 4 of 9 years, HN lowered (P<0.0821 to P<0.0003) ADG compared to LN. In only 2 of 9 years was there an NxE interaction (P<0,0537), the interactions expressing opposite effects when comparing the 2 years. In all but 3 years there was a linear (P<0.0606 to P<0.0019) relationship between endophyte infection rate and ADG. In only 1 of 9 years were quadratic effects significant (P<0.0407). Endophyte infestation consistently lowered steer AOG in a linear fashion with N effects less distinct,

Hay Supplementation And Stocking Rate Effects On Live Weight Gain Of Steers Grazing Rye And Ryegrass, Susan E. Sladden, David I. Bransby

IGC Proceedings (1977-2023)

The objective of this study was to evaluate continuous ad lib. supplementation of hay as a means of compensating for the uneven growth distribution of rye (Secale cereale) and ryegrass pastures (Lolium multiflorum) grazed by steers in the south-eastern USA. Pastures were continuously grazed by 230 to 270 kg steers at stocking rates of 2.5, 3.1, 4.1 and 4.9 head/ha with and without hay supplementation for 2 grazing seasons. On average, average daily live-weight gain (ADO) at the highest stocking rate (4.9 steers/ha) was 0.47 kg higher (P<0.01) when hay supplement was provided. Although not significant, in both years ADO tended to be higher for h_ay supplementation even at low stocking rates .

Seasonal Herbage Intake Of Once-Bred Heifers, A A. Khadem, S T. Morris, W J. Parker, R W. Purchas, S N. Mccutcheon

IGC Proceedings (1977-2023)

Once-bred heifer (ODH) beef production systems, which are new to New Zealand, involve mating heifers at 15 months of age to cnlve as 2-year-olds and then slaughtering the heifers (at less than 30 months of age) as prime beef. Never-pregnant, pregnant and lactating Hereford x Friesian heifers were used in 4 experiments. There were no significant differences between pregnant (days 260-270 of pregnancy) and never-pregnant heifers in their herbage organic matter intake (OMI), ingestive behaviour or daily live-weight gain (LWG) when a restricted pasture allowance of 7 kg DM/head/day was offered. Heifers at days 50-60 of lactation and never-pregnant heifers …