bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical control of Heliothis armiger (Hubner) in sweet corn
Authors: Hamilton JT , Muirhead WA
Published: March 2005

Four trials were conducted at Griffith, New South Wales for the control of the corn ear worm, Heliothis armiger, in sweet corn. A screening trial, where sprays were applied at 50% silking and 7 days later, showed that the pyrethroids permethrin and fenvalerate were the most effective chemicals. The insecticides used (g active ingredient ha-1) and the percentage of cobs damaged in each treatment were as follows: permethrin 100- 15%; fenvalerate 100- 17%; methomyl 450-22%; sulprophos 720-25%; methomyl 340-30%; monocrotophos 800-33%; CGA 15324 750-34%; endosulfan 740-39%; acephate 750-39%; chlorpyrifos 750-55%. Permethrin and fenvalerate were also found to be effective at rates of 50 and 75 g a.i. ha-1. Applications during the tasselling and early silking stages were more effective than sprays during the later silking stages.
Growth and wool production of wethers and induced cryptorchids in a Poll Merino flock
Authors: Egan JP , Russell DW
Published: March 2005

Ram lambs in a Poll Merino flock were either castrated or made cryptorchid at about four weeks of age and then run together in the one flock until 31/2 years old, The induced cryptorchids were heavier than their wether flockmates at each shearing (P < 0.001), the relative superiority increasing with age, from 5.2% at weaner shearing to 16.7% at 6-tooth shearing. Greasy fleece weights were heavier in the cryptorchids at the 4- and 6-tooth shearings only, by 5.3% (P < 0.05) and 1 1.3% (P < 0.01 ), respectively. No differences in visual wool quality were observed between the two groups, and the only difference detected by measurement of midside samples was a lower clean scoured yield percentage in cryptorchid fleeces at 6-tooth shearing (69.9% compared with 74.9% for wethers : P < 0.001 ). This lower yield resulted in similar estimated clean fleece weights at the 6-tooth shearing, but cryptorchids cut more clean wool at 4-tooth (P < 0.05). Clean fleece weight per unit liveweight was significantly higheri (P < 0.05) in the wethers than in the cryptorchids, by 8.7% at the 4-tooth and 11.8% at the 6-tooth shearing. Fleece weight index, a measure of the efficiency of wool production, was similar for both groups at these last two shearings. The possible value of induced cryptorchids as an alternative to wethers for wool production is discussed in the light of these results.
The influence of calcium and phosphorus in prelayer diets and their interaction with sodium chloride and potassium sulfate in layer diets on egg production and shell quality in crossbred layers
Authors: Karunajeewa H , Fox M
Published: March 2005

In a 43x2 factorial experiment, 576 White Leghorn x Australorp pullets attaining 50% egg production at about 180 days of age were given from 22 to 26 weeks of age pre-layer diets with 10.4 or 25.8 g kg-1 calcium and 6.2 or 10.9 g kg-1 phosphorus. From 26 to 74 weeks of age these pullets were given layer diets with three levels (0, 1.5 and 7.0 g kg-1) of added sodium chloride and two levels (0 and 6.0 g kg-1) of added potassium sulfate. The calcium content of the pre-layer diet had no significant effect on feed intake, bodyweight gain or tibia-ash content between 22 and 26 weeks of age, or on egg production, egg weight, feed conversion efficiency and mortality in the subsequent laying phase. The higher level (25.8 g kg-1) of calcium improved (P<0.05) the shell quality of the first eggs laid and prevented a decline in shell quality due to excess sodium chloride (7.0 g kg-1) in the layer diet. A phosphorus level of 10.9 g kg-1 of the pre-layer diet reduced (P<0.05) feed intake, and in the subsequent laying phase both hen-housed egg production and efficiency of feed conversion were reduced (P<0.05). The adverse effect on feed conversion efficiency was alleviated by adding potassium sulfate to the diet. The level of phosphorus in the pre-layer diet had no significant effect on tibia-ash content or egg shell quality. The dietary level of sodium chloride had no significant effect on egg weight, feed intake and bodyweight gain. The inclusion of sodium chloride at a level of 7.0 g kg-1 diet tended to depress rate of lay by 2.0% and during the first half of the laying cycle, increased mortality by 12.5% (P<0.05) and reduced egg shell weight and thickness (P<0.05) in birds given pre-layer diets with a low calcium content. A daily intake of 137 to 139 mg of sodium per bird was not adequate for maintenance of egg production and efficiency of feed conversion in crossbred layers. The sodium requirement of a crossbred layer given a diet containing meat and bone meal is about 160 mg/day. The adverse effects due to either a low intake of sodium or a high level of sodium chloride in the diet were alleviated by the inclusion of 6.0 g kg-1 potassium sulfate in the diet. The inclusion of potassium sulfate (6.0 g kg-1) in the layer diet increased rate of lay by 2.1% (P<0.05).
Native pasture response to nitrogen and sulfur under two cutting frequencies on a cracking clay soil in southern Queensland
Authors: Scattini WJ
Published: March 2005

The responses to fertilizers containing nitrogen (N) and sulfur (S) and to cutting frequency of native pasture containing black speargrass (Heteropogon contortus), forest bluegrass (Bothriochloa bladhii), and Queensland bluegrass (Dichanthium sericeum) were measured on a cracking clay soil derived from basalt. A factorial layout included N (as urea) at 0, 28, 56, 112 and 224 kg ha-1 year-1, superphosphate at 0 and 250 kg ha-1 year-1 plus potassium chloride at 0 and 125 kg ha-1 every second year and mowing every 3 and 6 weeks in summer from 1963-64 to 1969-70 inclusive. In order to investigate the effect of a possible S deficiency a split-plot design comprising five N and two S levels (0 and 67 kg ha-1 year-1) was superimposed in 1968-69 on those plots that did not receive superphosphate, and were cut every 6 weeks. A relation fitted for the N treatments that received superphosphate and were cut at weekly intervals from 1965-66 to 1969-70 indicated that yield depended on summer rainfall and on N through an interaction with rainfall. At high N levels, fertilizer containing superphosphate increased yield in most seasons through an interaction with N. The split-plot experiment showed that S was the element in the mixed fertilizer application responsible for pasture response. More frequent cutting reduced pasture yield (except for the first two summers because of experimental error) by 24% and N yields by 6%. N at rates above 56 kg ha-1 year-1 initially increased black speargrass basal area and later reduced it and the basal area of forest bluegrass at the highest N rate. The basal area of 'other species' was increased at higher N rates.
Effects of supplements of urea, molasses and sodium sulfate on the intake and liveweight of steers fed rice straw
Authors: McLennan SR , Wright GS , Blight GW
Published: March 2005

A pen feeding experiment was conducted in which steers were fed rice straw (0.68% nitrogen, 0.09% sulfur, dry matter basis) with urea alone; urea and molasses, or sodium sulfate; or all three supplements. The role of rice straw as a drought ration, and the effects of the supplements on intake and liveweight, were examined. Urea alone increased roughage organic matter intake by 14% (P=0.07) and total organic matter intake by 16% (P<0.05). Addition of molasses or sodium sulfate or both to the rice straw had no significant effect on intake (P>0.05). A urea supplement reduced liveweight loss from 149 to 86 g/head.d (P<0.05). In general, the small amounts of molasses and sodium sulfate had little effect on liveweight.
Bail-feeding of detergent in molasses for bloat control in dairy cows
Authors: Stockdale CR , Patterson IF
Published: March 2005

An experiment was done at Kyabram, In 1978, to develop a bail-feeding method of bloat control for dairy cows. The maximum concentrations of a number of detergents in molasses that were acceptable to more than 95% of 40 dairy cows were determined. These were 7, 39, 56 and 56% for the detergents Terics 18M10, 15A11, 12A23B acetate ester and 12A23B, respectively. Teric 12A23B was acceptable to at least 95% of cows on a routine basis at a concentration of 50% in molasses. This mixture prevented bloat: 99 instances of bloat were recorded among 22 cows receiving molasses alone compared with no bloat among a similar number of cows consuming a prophylactic dose of Teric 12A23B in molasses.
Nutritive value for lactating dairy cows of the pressed herbage remaining after the partial extraction of leaf juice
Authors: Stockdale CR , King KR , McKenzie DR
Published: March 2005

A series of six experiments compared the production of lactating dairy cows eating either fresh herbage or the pressed herbage remaining after the partial extraction of juice. Irrigated perennial pasture and irrigated lucerne (Medicago sativa) were used in different experiments. With forage-harvested pasture, extraction removed an average of 42.1 g of protein per kg dry matter (DM) of pasture processed. An average of 85% of the DM of the original fresh pasture was left as pressed pasture. The process lowered the in vitro digestibility, total nitrogen, and cell contents of the herbage, and raised the cell wall constituents. It also reduced herbage phosphorus, potassium, magnesium and sodium, but increased herbage calcium slightly. The milk yield of cows fed an equivalent DM intake of pressed residue was, on average, 6% lower than the milk yield of cows fed fresh pasture. The responses shown by the milk constituents were inconsistent. With lucerne, extraction removed an average of 95.9 g of protein from each kg of fresh herbage and an average of 74% of the lucerne was left as pressed lucerne. This reduced the quality of the pressed residue as determined by in vitro digestibility (5%), Kjeldahl nitrogen (19%) and neutral detergent fibre (27%). However, there was no significant loss of production for cows on the pressed herbage, although there were small differences. It is concluded that lucerne would appear to have the greater potential for a leaf protein extraction industry in the irrigated areas of the Goulburn Valley of Victoria.
Factors influencing the time required to shear Merino sheep and its importance as a breeding objective
Authors: McGuirk BJ , Ponzoni R , Atkins KD , Gilmour AR , Morley FHW , Maher L
Published: March 2005

Two sets of observations have been made on the time required to shear (TRS) Merino sheep. The first, in 1951, involved 98 rams and 75 ewes from one medium Peppin bloodline. Then, in 1975, TRS was recorded on 79 rams and 143 ewes from five different bloodlines, from a number of Merino strains. The effect of different production characters on TRS was estimated by least squares analysis, in models that included the effects of shearer, sex, bloodline (1975 only) and all first order interactions. In the 1951 data, TRS increased with increasing greasy fleece weight and with increasing skin fold in the rams (P <0.05). No production character had a significant effect on TRS in the ewes. In the 1975 data, TRS increased with increasing greasy fleece weight, skin fold, face cover and body weight in at least one sex, and when data from the two sexes were pooled (P <0.05). Skin fold and greasy fleece weight had the largest and most consistent effect. There were also significant differences between the bloodlines in TRS, which were found to be associated with differences between the bloodlines in skin fold, greasy fleece weight, and to a lesser extent, face cover. After studying the likely economic benefit of reducing TRS by selection, we concluded that under current economic situations, where any reduction in TRS would lower only the ancillary costs associated with shearing (shed hands, classing, etc.). TRS is not an important breeding objective for the Australian Merino wool industry.
Studies on the supplementary feeding of sheep consuming mulga (Acacia aneura). 5. The effect of cobalt and cottonseed meal supplementation
Authors: McMeniman NP , Niven DR , Crowther D , Gartner RJW , Murphy GM
Published: March 2005

In the first experiment designed to identify the deficiencies in mulga leaves, four groups of sheep were fed mulga and offered one of the following supplements; cobalt, sulfur, cobalt plus sulfur, and molasses. A fifth group acted as a control. All sheep received a phosphorus supplement. The cobalt supplement had no beneficial effect on liveweight or clean wool production. In contrast, the sulfur and molasses supplements significantly improved liveweight gain, clean wool production and sulfur balance. The liveweight and wool growth responses were more than twice as large in the sheep receiving a molasses supplement as in those receiving sulfur. In a second experiment, three groups of sheep on a diet of mulga leaves were supplemented with molasses and phosphorus and, in addition, two groups received 50 g/head.d of either formaldehyde treated or untreated cottonseed meal. Both cottonseed meal supplements significantly improved liveweight gain, but formaldehyde treatment of the meal had no additional effect. Under the conditions of the experiment rumen ammonia was a major limiting nutrient.
Nitrogen requirements of irrigated wheat on the Darling Downs
Authors: Strong WM
Published: March 2005

Eighteen fertilizer trials, each with five levels of nitrogen (N) and three levels of phosphorus (PI, were conducted on black earth soils of the Darling Downs to establish optimal economic rates of N fertilizer in commercial, irrigated wheat crops. The optimal economic rate of N with a fertilizer: wheat price ratio (kg N: kg grain) of 5:l, the yield response of 100 kg/ha of applied N, the yield without fertilizer, and the yield with fertilizer not limiting were calculated from derived yield response relations at each site. A multi-variate regression procedure was used to determine which soil or crop management factors significantly influenced the rate of N needed to optimize wheat yield. Delay in planting after June 1 and the level of residual mineral N in the soil at planting had strong negative effects on the response to fertilizer and the optimal rate of fertilizer required. The results indicate that yields of irrigated wheat may be below the economic optimum because of sub-optimal applications of N. Other soil and management factors such as available soil P and number of irrigations also affected grain yield. At 1 3 sites low protein wheat (< 1 1.4�1~) was produced with all but the highest two rates of N fertilizer and at two sites even the highest rate produced low protein wheat. The effect of N fertilizer applied at planting on grain protein concentration was changed by the yield response to the fertilizer application. Grain protein concentration was curvilinearly related (R2 = 0.81) to relative grain yield (yield as a proportion of the maximum yield); grain protein was at its minimum at a relative yield of 0.5. Although heavy rates of N fertilizer at planting increased grain protein concentration on a few sites, usually these applications led to an inefficient use of N fertilizer; apparent incorporation of fertilizer N into grain decreased with increasing rate of fertilizer.
Yield response of bananas to trickle irrigation
Authors: Trochoulias T , Murison RD
Published: March 2005

Supplementary trickle irrigation applied twice a week by single microtube at replacement rates of 0 (control), 20, 40, 60, 80, 100 and 120% of Class A pan evaporation (El from 1970 to 1976 increased bunch weight significantly (P= 0.02) above 40% E. Treatment 60% E gave a bunch weight of 27.6 kg compared with 25.7 for the control. The control, 20 and 40% treatments did not affect hand number from 1970 to 1976 while all other treatments increased hand number by 0.3 hands each year. Means of treatments over all years for fingers showed an annual increase of 4.6,4.0,5.8 and 5.0 fingers for 60,80,100 and 12O0Io treatments, respectively. Gravimetric sampling in 1974 showed the control plot had a lower water potential than other plots. There was little change in water potential in any of the other treatments. There was a significant linear decrease in water potential with increase in radius from the emitter. Root distribution studies showed that about 70% of the root systems in all treatments were concentrated in the upper 40 cm of soil. Forty per cent of the total root system was confined to a square, 60 x 60 cm, close to the base of the plant. Thus trickle irrigation with an emitter positioned near the base of the plant and a slow flow rate (3 litres/h) would reach most of the root system. Four out of the six years of the experiment were very wet (greater than 1700 mm rainfall). Only 29% of the total water over the 6 years in the 60% E treatment was provided by trickle irrigation. This experiment showed that 60% of Class A pan evaporation can be used as a reliable guide for the trickle irrigation of bananas on the East coast of Australia with free draining soils.
Sheep movement on slatted floors
Authors: Hutson GD
Published: March 2005

The effect of three factors on the movement of sheep on raised, slatted floors was tested: 1. light intensity below the floor - dark, medium, or bright; 2. alignment of battens - across or along the direction of movement; and 3. race width - 0.5 m or 1.5 m wide. Light intensity did not affect movement across the battens, but sheep were hesitant to move along the battens at medium and bright light intensities in 0.5 m wide races and at bright light intensities in 1.5 m wide races. In a Y-maze sheep showed no significant preference for moving on any of the four floor and light combinations used in six tests, but when the data were pooled, sheep showed a significant preference for moving across the direction of the battens, regardless of the light intensity below. These results suggest that movement of sheep through a shearing shed might be improved by covering the sides of the shed to exclude light from beneath the floor and by ensuring that the battens are always aligned across the direction of sheep movement.
Production by wethers fed oats, wheat, and lupins, with dry annual pasture in north-eastern Victoria
Authors: Kenney PA
Published: March 2005

An experiment was conducted at Rutherglen Research Institute in autumn 1979 to evaluate various grain supplements for the fattening of 18-month-old Merino wethers intended for the live export market. All sheep had mature, dry pasture, harvested during mid summer, freely on offer. This herbage contained 9% crude protein and was 47% digestible. Wheat, oats or lupins were fed as supplements at 0, 180, 360, 540 g/head.d and ad libitum. Mixed grain rations were also studied: lupins were fed at 0, 90, 180 and 270 g/head.d with either wheat or oats ad libitum. Wethers were fed these rations for nine weeks and fasted liveweight, wool growth, and body condition score were measured. Animals were then slaughtered and carcases weighed. Animal performance was positively related to the rate of grain intake. Ad libitum intakes of wheat and oats were low - 450 and 520 g/head.d respectively, and only maintained liveweights. in contrast, lupins fed ad libitum were consumed at 650 g/head.d, which resulted in significant increases in live and carcase weight - 4 kg and 3.8 kg respectively. Pasture intake was reduced by one third with all ad libitum grain rations. The addition of lupins at 180 g/head.d to wheat or oats increased the ad libitum intakes of the cereal grains to 550 and 650 g/head.d, respectively, with associated liveweight gains of 1.0 and 4.5 kg for the nine week period. Intake of cereal grains was generally low compared with that in other published reports; but all rations containing more than 10% lupins showed promise as supplements for fattening wethers.
Evaluation of legumes for use in short-term leys and natural pastures on the northern slopes of New South Wales
Authors: Archer KA
Published: March 2005

A range of temperate legumes was evaluated for winter and spring production for use as either short-term ley pastures, or, when sown from the air, as introduced species into natural pastures on the higher northern slopes of New South Wales. The species were evaluated with and without the annual application of a compound phosphorus and sulfur fertilizer in four experiments from 1975 to 1978. Haifa white clover (Trifolium repens cv. Haifa) was generally the most productive and persistent species with dry matter production in winter and spring ranging from 21 30 to 3600 kg/ha when sown into prepared seedbeds. In natural pastures with applied fertilizer, yields of Haifa ranged from 100 kg/ha in a dry year to 5000 kg/ha. Other persistent species in both ley and natural pastures were Namoi woolly pod vetch (Vicia dasycarpa cv. Namoi) (1110-3520 kg/ha and 470-3350 kg/ha, respectively) and Hunter River lucerne (Medicago sativa cv. Hunter River) (1290-2500 kg/ha and 480-2350 kg/ha, respectively). These were the only species to establish themselves satisfactorily in the natural pastures. Other species that showed good potential for ley pastures were Hamua red clover (T. pratense cv. Grasslands Hamua), Clare subterranean clover (T. subterraneum cv. Clare) and Kondinin rose clover (T. hirtum cv. Kondinin), but further evaluation of these legumes is required. The barrel medics were productive in their establishment year averaging 2560 kg/ha dry matter but mean yields in subsequent years were less than 100 kg/ha due to poor regeneration. The natural pastures needed fertilizer to ensure adequate levels of production from the sown legumes. In the ley pastures, a response occurred only in the second year of one experiment. The natural species did not respond to fertilizer. It is concluded that Haifa white clover, woolly pod vetch and lucerne offer significant potential for use in both ley and natural pastures on the north-western slopes
Moisture regimes of a cracking clay soil under furrow irrigated cotton
Authors: Chan KY , Hodgson AS
Published: March 2005

The moisture regimes of a self-mulching cracking grey clay under furrow irrigation in the Namoi Valley, New South Wales, were measured during the 1979-80 cotton season. A moisture profile of 0.1 9 g/g down to at least 150 cm depth was observed at permanent wilting point of the cotton plants. Five weeks later, further drying of the profile to 0.14 g/g (- 80 bars) at 150 cm had occurred, probably by evaporation through the cracks. The maximum storage capacity of the soil for available water to 1 50 cm depth was 19.5 cm of water. However, only 10.9 cm of this was replenished by furrow irrigation after 48 h of redistribution. The discrepancy was explained in terms of the rapid sealing of cracks due to slaking and swelling of the soil, which limited the wetting front to about 80 cm depth. Poor aeration prevailed in the soil after every furrow irrigation because a region of very low air-filled porosity (<5%) was created in the wetted subsoil.
Laboratory estimates of the nutritive value of some herbaceous native legumes
Authors: Cohen RDH , Wilson GPM
Published: March 2005

Forty-four accessions of herbaceous native legumes from the genera Glycine and Galactia were grown in a glasshouse in a soil-sand-nutrient mixture that contained adequate phosphorus, potassium, calcium, magnesium, sulfur and molybdenum for plant growth. They were grown as individual plants with four replications of each. All plants were cut to soil level on August 18; regrowth was cut on October 7, November 22 and December 30 (harvests 1,2 and 3). The herbage was dried and analysed for nitrogen (g N/kg OM), phosphorus (g P/kg OM) and organic matter digestibility (% OMD). There were significant differences between the accessions for values of dry matter yield (P<0.001), nitrogen content (P<0.01), phosphorus content (P<0.001) and OMD (P<0.05). The mean nitrogen content declined at each harvest (40.6,33.7 and 31.7 g N/kg OM, respectively; P<0.05) and OMD of the herbage at harvest 3 was less than that at 1 and 2 (70.4, 71.1 and 67.6%, respectively; P<0.05). Herbage from harvest 1 had significantly greater P values than that from harvests 2 and 3 (4.7,4.2 and 4.4 g P/kg OM; P< 0.05). Plant yield was correlated with both nitrogen yield (r = 0.98; P<0.001) and phosphorus yield (r = 0.93; P<0.01) but not with OMD. Nitrogen content and digestibility were correlated (r = 0.48; P<0.01) but neither attribute was significantly correlated with phosphorus content. Samples of native herbaceous legumes belonging to the genera Desmodium and Kennedia and of some exotic legumes were collected from a nursery and analysed for N, P and OMD. The N and P values of all these legumes were in the range 31.9-39.2 g N/kg OM and 3.0-4.1 g P/kg OM, and compared favourably with those of the legumes grown in the glasshouse. The OMD of the exotic legumes (range 61.3-85.2%) compared favourably with those of the native legumes grown in the glasshouse but the natives Desmodium spp. and Kennedia spp. (range 26.7-35.4%) were very much lower than the Glycine spp. and Galactia spp.
Poor nodulation of lupins and tropical legumes in northern New South Wales
Authors: Philpotts H
Published: March 2005

Nodulation problems with tropical legumes and lupins in northern New South Wales appeared due to the inoculant's failure to establish itself around the seedling root, and were more severe with direct drilling. The cause of this was investigated in a number of laboratory, glasshouse and field experiments. Krasnozem soils were found to be more inhibitory than three other types, but this did not appear related to pH or manganese content. Raising the pH of krasnozem soil with lime did not improve survival of rhizobia unless the soil was autoclaved. Soil extracts suppressed multiplication in sterile nutrient sand except when micro-filtered, but a greater increase occurred with no extract. Extracts of both carpet grass and kikuyu depressed nodulation of glycine (Neonotonia wightii) but only the carpet grass extract adversely affected Siratro (Macroptilium atropurpureum). Root washings of the two grasses restricted multiplication of Rhizobium lupini, kikuyu having the greater effect. Lupin seedlings growing in the presence of kikuyu roots had fewer rhizobia in the root zone and were less well nodulated except when inoculated at a high rate. The susceptibility of WU425 and the clover strain TA1 appears not to differ and the host plant (lupin or clover) did not influence rhizobium numbers in the rhizosphere. In the field both the number of rhizobia in the root zone of lupins and the percentage of plants nodulated, increased with increasing rate of inoculation. The results indicate that suppression is due to both micro-organisms and a heat labile chemical factor.
Production responses in selenium supplemented sheep in northern New South Wales. 2. Liveweight gain, wool production and reproductive performance in young Merino ewes given selenium and copper supplements
Authors: Wilkins JF , Kilgour RJ , Gleeson AC , Cox RJ , Geddes SJ , Simpson IH
Published: March 2005

Young Merino ewes on five commercial properties in northern New South Wales were supplemented with selenium and their production was compared with untreated flock mates. They were studied from weaning till first lambing at about two years of age. Treatments of 5 mg selenium were given orally every six weeks for approximately 12 months. Copper treatments were also included to test for a possible concurrent deficiency or interaction with selenium. There were significant responses to selenium in liveweight in four of the five flocks and in wool production in two of the flocks at both shearings. Reproductive performance at first mating was also significantly better in two flocks. There were no beneficial effects of copper treatment nor were there any significant interactions with selenium treatment in any aspect of production measured.
Control of goitre in lambs by injection of ewes with iodized poppy seed oil
Authors: Statham M , Koen TB
Published: March 2005

The value of a single injection of 1 ml of iodized poppy seed oil in ewes was examined to prevent goitre in their lambs in an iodine deficient area in northern Tasmania. Control of goitre was achieved for only two years as assessed by thyroidal radio-iodine uptake in the ewe and histological changes in the lamb's thyroid. On a group basis the slope of the radio-iodine uptake curve in ewes was found to give an accurate reflection of the animals' iodine status as shown by the lambs' thyroid histology. The treatment had no effect on liveweight gain or fleece growth in lambs, but in the year after the treatment the ewes had a 6% increase in fleece weight.
Effect of late application of nitrogen on the yield and protein content of wheat
Authors: Strong WM
Published: March 2005

On the Darling Downs the growth and yield of a semi-dwarf wheat (cv. Oxley) under supplementary irrigation was increased by the application of up to 400 kg/ha of nitrogen (N) at planting. Nitrogen at 50 or 100 kg/ha applied at the boot stage to supplement 100 kg/ha applied at planting increased grain yield by 459 and 478 kg/ha, respectively. However, yields were still below those where all the N was applied at planting. In contrast, supplementary N (0, 25, 50 or 100 kg/ha) at flowering or after flowering generally did not increase grain yield. One exception to this was where only 50 kg/ha was applied at planting; an additional 100 kg/ha at flowering increased grain yield by 602 kg/ha. Applied at planting, more than 200 kg/ha of N was needed to produce premium grade wheat (i.e. protein content above 11.4%). To achieve this protein content where 100 kg/ha had been applied at planting an additional 100 kg/ha was needed at the boot stage or 50 kg/ha at flowering. Applied after flowering, up to 100 kg/ha of additional N produced wheat of a protein content too low to attract a premium payment. A similar quantity of N was assimilated whether the entire N application was applied at planting or where the application was split between planting and boot or flowering. Less N was assimilated when the application was split between planting and after flowering. More N was assimilated from soil than from foliar applications at the boot stage. Soil and foliar applications were equally effective at flowering in increasing the amount of N assimilated as well as the grain protein content. However, after flowering foliar application was the more effective method. The application of N at flowering to increase the protein content of this semi-dwarf cultivar is not an attractive commercial practice. The price ratio of premium to Australian Standard White wheat in recent years (<1.071 ) is less than that needed (1.0954-1.3013) to justify splitting the N application to lift grain protein content above 11.4% at the expense of yield.
Growth and yield studies of Lupinus angustifolius and L. albus in Victoria
Authors: Boundy KA , Reeves TG , Brooke HD
Published: March 2005

The effect of serial planting on dry matter production, leaf area, grain yield and yield components cf Lupinus angustifoiius (cvv. Uniwhite, Uniharvest and Unicrop) and L. albus (cv. Ultra) was investigated in field plots at Rutherglen in 1973 and 1974. Delayed planting reduced dry matter production of all cultivars, and leaf area for Ultra. Differences in dry matter partitioning were observed between the late flowering Uniharvest, and the early flowering Unicrop and Ultra. In Uniharvest, delayed plantings resulted in a greater proportion of total dry matter being produced during the flowering phase, whereas the reverse was true for Unicrop and Ultra. The later flowering cultivars showed marked grain yield and yield component reduction with later sowing. Yields were reduced by 160.6 kg/ha and 222.5 kg/ha for each week's delay in sowing Uniharvest and Uniwhite, respectively. This effect was offset in the early flowering cultivars by greater development of lateral branches. In addition, when Unicrop and Ultra were planted in April, pod and flower abortion on the main stem resulted from low temperatures at flowering time. Optimum sowing time was early April for Uniwhite and Uniharvest, and early May for Unicrop and Ultra. Excellent vegetative growth under ideal moisture conditions highlighted the poor harvest indices of lupins and the scope for genetic improvement in the genus.
Initial and medium-term responses of white clover to three sulfur fertilizers on a basaltic soil
Authors: McLaughlin BD , Holford ICR
Published: March 2005

The short and medium-term effects of three sulfur fertilizers on white clover pasture were measured on a sulfur-deficient basaltic soil in the Northern Tablelands of New South Wales between 1976 and 1979. The treatments were a single application of elemental sulfur, gypsum, and sulfur-fortified superphosphate (SF45) at 0, 20, 40, and 80 kg S/ha and three annual applications of elemental sulfur and gypsum at 0, 10, 20 and 30 kg S/ha. Gypsum and SF45 gave the largest effects in the first year, and elemental sulfur and SF45 caused the largest residual effects in the third year. A single application of 20 kg S/ha gave near maximum yields over the three year period provided that most of the sulfur was supplied in the elemental form. However, to achieve maximum yields in the first year about 20% of the sulfur was required as sulfate. Likewise maximum yields in the third year required a fresh application of 10 sulfate S/ha. The relatively large residual effect of gypsum was attributed to the slow-leaching soil, and the resistance of the coarse textured elemental sulfur (65% >0.5mm) to leaching by the high summer rainfall.
Milk yields from feeding maize silage and meat-and-bone meal to Friesian cows grazing a tropical grass and legume pasture
Authors: Davison TM , Marschke RJ , Brown GW
Published: March 2005

Twenty Friesian cows in mid-lactation were used in a 2x2 factorial experiment to determine the responses in milk yield, milk composition and liveweight to maize silage supplement (3 kg dry matter/cow.d, or free access during the day) with or without a meat-and-bone meal supplement (5 silage: 1 meat-and-bone meal, on a dry matter basis). Cows grazed green panic (Panicum maximum var. trichoglume) and glycine (Neonotonia wightii cv. Tinaroo) mixed pastures at 2.5 cowslha. Experimental treatments were maintained for eight weeks after which cows grazed as one group on unsupplemented pasture for a further eight weeks. Milk yields averaged 14.7 and 16.0 kg/cow.d for the low and high silage levels (P < 0.01), and 15.8 and 14.8 kg/cow.d with and without meat-and-bone meal (P < 0.05). There was a residual effect of 1.2 kg milk/cow.d (P < 0.05) for eight weeks after the experimental period from feeding silage at the high level. Feeding meat-and-bone meal reduced milk fat percentage from 3.61 to 3.30% (P< 0.05). Protein yield and the short-chain fatty acid (C4-C16) content of milk fat were increased by increasing the level of intake of silage (P < 0.01), while feeding meat-and-bone meal increased protein yield (P < 0.05), but decreased the short-chain fatty acid content of milk fat (P < 0.05). Cows lost an average of 15.2 kg liveweight at the low silage level and gained 6.7 kg at the high silage level (P< 0.01) over the eight weeks of experimental feeding.
Effect of the liveweight of caged sheep on the digestibility of grasses fed ad libitum
Authors: Minson DJ , Ratcliff D
Published: March 2005

To determine the effect of liveweight on the digestibility of dry matter, 29 grass cuts were each fed ad libitum to between five and ten sheep of the same age. In the complete experiment 255 different sheep were used. All 255 observations were used to calculate regressions relating digestibility to liveweight for each of the 29 grasses. When the data were divided into four digestibility groups (< 50, 50-55, 55-60, > 60%) the regression coefficient for grasses with a digestibility less than 50% was 0.373 (P < 0.01). The regression coefficient for the other three groups varied between -0.080 and 0.049 (P> 0.05). The data were also analysed by comparing the results obtained with the heaviest and lightest sheep on each of the 29 cuts. When the 29 cuts were divided into four groups, as described above, there was no significant difference in mean digestibility between heaviest and lightest groups for feeds having a digestibility greater than 50%. For cuts with less than 50% digestibility the heaviest sheep digested the grass 4.2 percentage units more efficiently than the lightest sheep (P < 0.05). There were no significant differences in the level of feed residues. It was concluded from both methods of analysis that any effect of liveweight on the digestive efficiency of sheep is limited to forages with a dry matter digestibility less than 50%.
Effect of artificial wind on sheep movement along indoor races
Authors: Hutson GD , van Mourik SC
Published: March 2005

The effect of artificial wind on sheep movement along indoor races was tested in two experiments. In experiment 1 a large wind machine was used to produce wind speeds of 0, 5, 10, 15, 21, 23 and 25 km/h. The test sheep were aligned in a starting pen to face the wind. Sheep entered both narrow and wide races faster when there was a wind, but there were no significant differences between the various wind speeds. Once sheep were moving along the race neither wind nor absence of wind affected rate of movement. In experiment 2 the wind machine was used with test sheep randomly orientated in the starting pen. As a control, the noise produced by the machine at each wind speed was recorded and played back through speakers at the end of the race. Wind speed had no effect on sheep movement out of the pen and along the race. It was concluded that an artificial wind can be used to attract sheep to enter a race if they are facing into it, but wind does not stimulate sheep to change orientation in order to move.
Factors influencing fleece rot in sheep
Authors: Lipson M , Hilton RA , Watts JE , Merritt GC
Published: March 2005

Fleece samples were collected from 15 susceptible and 15 resistant sheep from 14 flocks in four States. All flocks had a high incidence of fleece rot. Each sample was examined for wax and suint contents, suint pH, cohtent of non-wool insoluble protein (insoluble nitrogen), water uptake and coefficient of variation of fibre diameter. Average contents of suint and insoluble nitrogen were significantly higher in the susceptible animals from 11 and 10, respectively, of the 14 flocks. Water uptake and suint pH were significantly higher in eight and seven flocks, respectively, while coefficient of variation of fibre diameter and wool yield were each significantly higher in six flocks. Wax to suint ratio could differentiate susceptible and resistant sheep in nine flocks but this is due almost entirely to the effect of suint content. Thus, in any selection program, within a flock there should be little need to estimate wax, as suint on its own should suffice. A rapid method for estimation of suint is now available, which should be useful in the identification of sheep resistant to fleece rot.
Performance of grazed creeping-rooted lucernes on two soils in central Queensland
Authors: Gramshaw D , Bishop HG , Ludke DH
Published: March 2005

The creeping-rooted lucernes (Medicago falcata x M. sativa), cv. Walkabout and breeder's line ECRS 1, were compared with M. sativa cvv. Hunter River and Siro Peruvian for persistence and production under dryland conditions on alluvial and solonetz soils at Biloela and Theodore in central Queensland. The lucernes were sown with green panic (Panicum maximum var trichoglume cv. Petrie) and were grazed intermittently by cattle. Established lucerne populations were similar on each soil, but varied among lines in the range 25-55 plants/m2, with creeping-rooted lucernes having the lowest. Persistence on the two soils differed markedly; after two years, populations had decreased to between 7-22 plants/m2 on the alluvial whereas less than 3 plants/m2 remained on the solonetz. Survival of both creeping-rooted lines was inferior to that of Hunter River on both soils, but only significantly (P < 0.01) so on the alluvial soil. Dry matter yields from the creeping-rooted lines on the solonetz soil during the first year were similar and averaged 2.6 t/ha, compared with Hunter River, 3.4 t/ha, and Siro Peruvian, 6 t/ha.
The relation between wheat yield and early damage of roots by cereal cyst nematode
Authors: Simon A , Rovira AD
Published: March 2005

A survey of 14 farmers' fields in the Northern Adelaide Plains in 1978 showed that cereal cyst nematode (Heterodera avenae Woll.) was the major factor limiting wheat yields, with a relation of r = -0.86 (P < 0.001) between damage to wheat roots at the seedling stage and grain yield. None of the 12 physical and chemical properties of the soils measured was related to cereal cyst nematode damage or grain yield. Samples taken from experimental plots with similar soil and climate showed a build up of H. avenae after four successive wheat crops and highly significant negative correlations between the damage to seminal roots by H. avenae, dry weight at flowering, and grain yield. A highly significant positive correlation of 0.84 existed between the damage to the seminal roots and the number of females (white cysts) on the roots at flowering.
Nutrient status of apple trees in two productive orchards in Tasmania
Authors: Graley AM
Published: March 2005

The nutrient status of apple trees was assessed in two productive orchards on different soils in southern Tasmania. The concentration of nitrogen, phosphorus, potassium, calcium, and magnesium in leaf samples was determined over three growing seasons, once in the first year and at three-weekly intervals in the second and third years. Comparisons were made with overseas standards of sufficiency in the elements, and relations were sought with apple yields and tree growths. For most of the elements there was a period of relative stability in concentration towards the latter half of the growing season (late January-early February). The representative concentration of all elements, estimated during this period, declined only slightly in the successive years but remained at sufficient levels, even though growth of the trees and apple yields increased greatly. A moderately high concentration of potassium in the leaves of a number of trees appeared to be associated with a depressed yield of the apples, apparently because it lowered the concentration of magnesium in the leaves.
Genetic relations among five lines of Stylosanthes guianensis
Authors: Sumberg JE , Miles JW
Published: March 2005

Genetic relations among five lines of Stylosanthes guianensis were studied by means of a diallel cross. Two parents each of S. guianensis var. guianensis and of the 'tardio' group of var. guianensis, plus one parent of var. intermedia (cv. Oxley) were crossed in all combinations. Pollen fertility, seed set, and shoot length of F1 hybrids were used to measure genetic relations. Pollen fertility of the var. guianensis x tardio hybrids did not differ from pollen fertility of var. guianensis x var. guianensis and tardio x tardio hybrids. Fertility of hybrids of Oxley was considerably lower than that of hybrids of var. guianensis and tardio parents. While parents were found to differ in seed set, the data provided no evidence of a reduction in seed set in hybrids due to incompatibility between the var. guianensis and tardio accessions. No seeds were harvested from hybrids of Oxley. Heterosis for shoot lenqth was observed in all crosses between var. guianensis and tardio parents,- while only one of four hybrids of Oxley exceeded mid-parent shoot length.
Effect of parent material, natural available soil boron, and applied boron and lime on the growth and chemical composition of lucerne on some acidic soils of the Central Tablelands of New South Wales
Authors: Haddad KS , Kaldor CJ
Published: March 2005

Fifteen acidic soils (0-1 5 cm), three from each of the five main parent materials in the Central Tablelands of New South Wales, were collected for a glasshouse experiment. The hot water soluble boron content of these soils and some other related soil properties were measured. Boron at nil and 1.5 �g/g air-dried soil and lime at nil and 670 �g/g air-dried soil in a factorial combination were applied to the soils. The effects of the treatments on the performance of lucerne (Medicago sativa cv. Hunter River) grown on these soils were studied. Boron application tended to increase the production of lucerne dry matter on sandstone, shale and slate, and granitic soils, but not on basaltic or alluvial soils. Also, it increased the boron concentration in the leaves of lucerne grown in all soils and consequently, reduced the calcium to boron ratio. The boron levels that produced 90% of the maximum yield and below which boron deficiency symptoms were manifested by the plants, were 0.34 �g/g in air-dried soil and 25 �g/g in oven-dried leaves. There was a linear correlation (r = 0.98) between the hot water soluble boron content of the untreated soils and the boron concentration in the leaves. The hot water soluble boron content of the soils derived from sandstone, shale and slate, and granite was much lower than the basaltic or alluvial soils and were nearly equal to or below the determined critical level. Although liming had the tendency to induce the symptoms of boron deficiency, the effect of lime was greater than boron in increasing the yield. The role of lime in eliminating the problems of these acidic soils and hence promoting the yield of lucerne is discussed.
Current requirements of copper for pasture and sheep production on sandy soils in the upper south-east of South Australia
Authors: Hannam RJ , Judson GJ , Reuter DJ , McLaren LD , McFarlane JD
Published: March 2005

The current requirement of copper for optimum growth of pasture, and production and health of sheep on the sandy soils of the upper south-east regions of South Australia was investigated in three consecutive years at three sites each of which had previously been treated once with copper. In a glasshouse study copper applied to virgin soil, obtained from areas next to the sites, increased the growth of subterranean clover. Dry matter production of herbage grown in enclosures on developed soil that had received copper 14-23 years earlier did not respond to additional applications of copper fertilizer. The concentration of copper in grazed herbage, where no additional copper was applied, was usually greater than 6 mg/kg dry matter. Sheep liveweight and greasy wool production were not increased by subcutaneous injections of copper at any site and the concentrations of copper in blood plasma and liver of untreated sheep were consistently greater than those associated with copper inadequacy in sheep. Also the copper treatments did not affect the fibre diameter or copper concentrations of the fleeces, and steely wool was not observed. We concluded that a copper dressing of 2 kg/ha to these soils provides adequate copper for pasture and sheep production for at least 23 years and that repeated dressings are unwarranted.
The effect of potassium and nitrogen fertilizers on the yield, fruit quality and leaf analysis of Imperial mandarins
Authors: Chapman JC
Published: March 2005

A potassium and nitrogen nutrition trial with Imperial mandarins was conducted for four years at Gayndah in south-eastern Queensland with the following results. Annual applications of 0.5 or 2.0 kg potassium/tree increased average yields by 12.3 and 22.2%, respectively, over those of the nil control, which yielded an average of 163 kg fruit/tree.year. Fruit diameter and rind thickness were also increased and fruit colour development was hastened by the applied potassium. Average leaf levels of potassium resulting from the 0,0.5 and 2.0 kg treatments were 0.85, 0.93, and 1.35% in non-fruiting terminals and 0.40, 0.44 and 0.77% in fruiting terminals. The potassium levels in non-fruiting terminals fluctuated from year to year in an inverse pattern to the alternate yield pattern whereas the levels in fruiting terminals remained stable. With an annual application of 0.4 kg nitrogen/tree average leaf nitrogen levels were 2.83% in non-fruiting terminals and 2.32% in fruiting terminals. At 0.7 kg nitrogen/tree both these figures were increased by 0.11% but there was no effect on yield or fruit quality. When the nitrogen was applied in two dressings in winter, yield was 9% greater than when the same quantity was applied in spring-summer.