bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of temperature and relative humidity on the thermoregulatory responses of grouped and isolated neonate chicks
Authors: Misson B. H. 
Published: March 2009

SUMMARYMeasurements of O2 consumption (Vo2), CO2 production (VCO2) evaporative water loss and rectal temperature (Tr) have been made and metabolic heat production (H), evaporative heat loss (—E) and respiratory quotient (RQ) calculated with individual and groups of 1-day-old chicks at constant ambient temperatures (To) in the range 20—43 °C and 80 or 20% relative humidity (R.H.).Minimal metabolism (10·7 kJ/kgJ/h) occurred at 35 °C.One-day-old chicks act as heterotherms outside the zone of minimal metabolism since neither H nor —E are sufficiently developed mechanisms to maintain homeothermy.Huddling allows chicks to maintain a higher TT at a lower H per unit metabolic body size.Reducing E.H. from 80 to 20% raised the upper temperature survival limit (UTSL) from 41·5 to 43 °C.Panting was initiated when Ta = 38 °C and Tr was between 39·5 and 39·9 °C.
Nitrogen and dry-matter accumulation in high lysine and normal varieties of barley
Authors: Rhodes A. P. , Jenkins G. 
Published: March 2009

SUMMARYDry matter and Kjeldahl nitrogen estimations were made on the roots and shoots of the barley varieties Riso 1508, Hiproly and Maris Mink from the seedling stage to maturity under three nitrogen treatments. After heading, the shoots were further separated into ears and stems plus leaves. Total plant nitrogen uptake was greatest in the high lysine variety Riso 1508 and was associated with a greater production of dry matter. However, the proportion of total plant nitrogen and dry matter in the grain was highest in the variety Maris Mink and this effect increased with increasing nitrogen supply. The comparative efficiency of dry-matter production and nitrogen translocation of these varieties is discussed in relation to breeding barley of improved protein yield and quality.
Aflatoxin control in preharvest maize: effects of chitosan and two microbial agents
Authors: Cuero R. G. , Duffus E. , Osuji G. , Pettit R. 
Published: March 2009

SUMMARYGrowth and aflatoxin production ofAspergillus flavusin preharvest maize grown in Texas, USA in 1989 were determined after treatment with chitosan,Bacillus subtilisandTrichoderma harzianum. Individual or combined control treatments were applied at the milk stage of ear development, 48 h before or after kernel inoculation with an aflatoxigenic isolate ofA. flavus. Single and combined treatments reducedA. flavusgrowth and aflatoxin production. Toxin accumulation was significantly (P< 0·05) reduced, in some instances to non-detectable concentrations by single pretreatments. EitherB. subtilisor chitosan as independent treatments applied 48 h before inoculation withA. flavusinhibited aflatoxin production.
Growth of axillary buds of Brussels sprouts (Brassica oleraceavar.bullatasub var.gemmifera)
Authors: Wilcockson S. J. , Abuzeid A. E. 
Published: March 2009

SUMMARYIn 1984 and 1985, the growth of axillary buds of Brussels sprouts plants was studied at Cockle Park, Northumberland, UK. Bud growth commenced in late September or early October and continued at all nodes until the final harvest in December. Total bud yield increased at a broadly constant rate until late November but at a decreasing rate thereafter. Plants producedc.100 nodes with buds ≥ 5 mm diameter. The largest buds werec.40 mm diameter and 25 g fresh weight. Bud size increased from the base of the stem upwards to between the 20th and 40th nodes and then decreased towards the apex. Nodes 20–40 (20% of the total) producedc.40–45% of total bud yield. The size profile of leaves along the stem followed a similar pattern to the buds and the largest buds were in the axils of the largest leaves. There were close relationships between bud fresh weight and size,bud fresh weight and size, bud fresh weight and volume and log10bud fresh weight and log10bud size (r2≥ 0·995). The density of buds wasc.0·8 and bud fresh weight doubled for each 5 mm increase in bud diameter.Current photosynthesis of the leaf canopy was apparently the major source of assimilates for bud growth. A C14tracing experiment suggested that growth of individual buds was mainly supported by their subtending leaves. There was no evidence of re-translocation of dry matter from dying leaves or the stems to buds or of substantial production of dry matter by the buds themselves. Rates of bud photosynthesis were only about 10% of the rate of leaves. The continued increase in bud fresh weight and size at the lowest nodes when leaves were senescing rapidly and after they had abscissed was probably mainly the result of water uptake rather than dry matter accumulation.
Tropical crop and crop by-product additives can improve the quality of taro leaf (Colocasia esculenta) silage
Authors: Ash A. J. , Elliott R. 
Published: March 2009

SUMMARYThe nutritive value of taro leaf (Colocasia esculenta) silage, with or without various crop or crop byproducts as additives, was evaluated in two experiments in Western Samoa in 1988 and 1989. In Experiment 1, laboratory silos were used to assess the quality of eight taro leaf silages which were either ensiled fresh or wilted overnight. Taro leaf ensiled alone was poorly preserved with a pH of 5·4 and high concentrations of ammonia-N and volatile fatty acids. In contrast, silages with crop byproduct additives rich in water soluble carbohydrates (WSC), mainly molasses, ripe banana or papaya pulp, were of high quality with pH levels ofc. 4 and low concentrations of volatiles. Copra meal, although low in WSC, was able to produce a satisfactory silage when added to taro leaf through its ability to restrict fermentation.Despite only a small increase (14·2%) in silage dry matter (DM) content, wilting of taro leaves resulted in silage of significantly higher quality than that made from fresh leaves. Most of the benefit of wilting was attributed to better fermentation conditions rather than a restricted fermentation.Two of the better silages from Experiment 1, taro/molasses and taro/banana, were prepared on a larger scale in earth pits and fed to goats in a second experiment. Both silages were highly palatable and digestible; DM intakes of 47 and 63 g/kg W0·75per day and organic matter digestibilities of 69·0 and 74·9% were recorded for the banana and molasses silages, respectively.It was concluded that taro leaf is a suitable forage for ensilage, and when combined with additives rich in WSC, a forage of high nutritive value can be produced.
Use of bovine somatotropin in the tropics: the effect of sometribove on milk production of Bos indicus, dairy crossbred and Bos taurus cows in Zimbabwe
Authors: Phipps R. H. , Madakadze C. , Mutsvangwa T. , Hard D. L. , Kerchove G. De 
Published: March 2009

SUMMARYTwenty-four Bos indicus cows of the Mashona/Nkone breeds, 36 dairy crossbreds (Mashona/ Nkone x Friesian), 48 Holsteins, 42 Friesians and 25 Jerseys were used to study the effect on milk production of sometribove (500 mg), a prolonged release formulation of bovine somatotropin (BST). BST was administered at 14-day intervals by subcutaneous injections into the ischio-rectal fossa which lies lateral to and on either side of the anus (tailhead). With the exception of the Bos indicus cows, which received seven injections of BST, all other treated cows received eight.The administration of BST to Bos indicus cows, significantly (P < 0·05) increased milk yield from 0·45 to 1·75 kg/cow per day, and extended lactation. These effects combined to increase total milk production during the 14-week trial from 226 kg for the control group to 993 kg for the group treated with BST. With dairy crossbreds the use of BST significantly (P < 0·01) increased milk yield from 8·6 to 11·0 kg/cow per day. Milk composition for Bos indicus and dairy crossbreds wasunaffected by the administration of BSTBST significantly (P < 0·05) increased milk yield in Jersey (+ 2·9 kg/day), Friesian (+ 3·6 kg/day) and Holstein (+ 2·7 kg/day) cows. Bodycondition of treated cows tended to be slightly lower than that of the control cows at the end of treatment.Cows remained in excellent health throughout all the trials. Farmers commented on how easy the injection was to give in the tailhead site, and on the complete absence of any adverse injection site reaction.
Distribution, transformations and recovery of urinary sulphur and sources of plant-available soil sulphur in irrigated pasture soil–plant systems treated with35sulphur-labelled urine
Authors: Nguyen M. L. , Goh K. M. 
Published: March 2009

SUMMARYA field plot experiment of 271 days duration was conducted on New Zealand irrigated pastures, commencing in the summer (January) 1988, on a Templeton silt loam soil (Udic Ustochrept) by applying35sulphur (35S)-labelled urine (250 μCi/g S with 1300 μg S/ml) to field plots (600 × 600 mm) at a rate equivalent to that normally occurring in sheep urine patches (150 ml/0·03 m2) to investigate the distribution, transformations and recovery of urinary S in pasture soil–plant systems and sources of plant-available soil S as influenced by the available soil moisture at the time of urine application and varying amounts of applied irrigation water. Results obtained showed thatc.55–90% of35S-labelled urine was incorporated into soil sulphate (SO42−), ester SO42− and carbon (C)-bonded S fractions within the major plant rooting zone (0–300 mm), as early as 27 days after urine application. Hydriodic acid (Hl)-reducible and C-bonded soil S fractions showed no consistent trend of incorporation. On day 271, labelled-S was found in soil SO42−, Hl-reducible S and C-bonded S fractions to a soil depth of 500 mm, indicating that not only SO42− but also organic S fractions from soils and35S-labelled urine were leached beyond the major rooting zone. A large proportion (c.59–75%) of35S-labelled urine was not recovered in pasture soil–plant systems over a 271-day period, presumably due to leaching losses beyond the 0–300 mm soil depth. This estimated leaching loss was comparable to that (75%) predicted using the S model developed by the New Zealand Ministry of Agriculture. The recovery of urinary S in soil–plant systems over a 271-day period was not affected by different amounts of irrigation water applied 7 days after urine application to soil at either 50 or 75% available water holding capacity (AWHC). However, significantly lower S recovery occurred when urinary S was applied to the soil at 25% AWHC than at field capacity, suggesting that urinary S applied at field capacity might not have sufficient time to be adsorbed by soil particles, enter soil micropores or be immobilized by soil micro-organisms. Both soil ester SO42− and calcium phosphate-extractable soil S in urine-treated soils were found to be major S sources for pasture S uptake. Labelled S from35S-labelled urine accounted forc.12–47% of total S in pasture herbage.
The effects of seed size, autumn nitrogen and plant population density on the response to delayed sowing in winter oil-seed rape (Brassica napus)
Authors: Mendham N. J. , Shipway P. A. , Scott R. K. 
Published: March 2009

SUMMARYThe aim of the experiments reported here was to investigate the possibility of minimizing yield losses due to late sowing by increasing leaf area and radiation interception during the pre-flowering period. The use of large seed did increase leaf area, radiation interception and crop weight at flowering. Normally this would be expected to lead to increased yield of late sowings, but hot, dry conditions severely affected all crops during seed growth. Applying fertilizer nitrogen in the seed bed boosted pre-flowering growth of early but not late sowings, probably because low temperatures prevented a response in the latter. Increasing plant population density did improve leaf cover and radiation interception until just before flowering, but leaf canopies in late-sown, low density crops were then able to expand more and function for longer owing to less shading by flowers and pods. Seed retention was improved and, even with as few as 8 plants/m3 in 1973–4, a worthwhile yield was still obtained.
The pH and nutrient status of agricultural soils in England and Wales 1969–83
Authors: Church B. M. , Skinner R. J. 
Published: March 2009

SUMMARYA representative soil sampling survey of arable and grassland fields in England and Wales between 1969 and 1983 is described.The results show that of the rotationally cropped area 29% was below pH 6·5, and of the continuous grassland 46% was below pH 6·0. Levels of P and K were satisfactory except that 15% of grassland soils were low for P.Data obtained by re-sampling the same fields at intervals of 5 years show that changes in the proportions of crops grown at different levels of pH and nutrients have been small. There has been some increase in the proportion of continuous grassland at lower pH, but the proportions of soils with low P and K have tended to decrease.
Oestrus detection by mounts received in Friesian × Bunaji and Bunaji heifers
Authors: Johnson A. O. , Oni O. O. 
Published: March 2009

SUMMARYBehavioural oestrus was studied using 32 Friesian × Bunaji and 29 Bunaji heifers standing for mounts by either vasectomized bulls or heifer herdmates. The study was conducted from 06.00 to 12.00 h and from 13.00 to 18.00 h local time for 96 days. All the 61 heifers showedoestrus. The mounts received by the heifers ranged from 68 to 170, being few between the first 24 days but increasing later. A total of 171 oestrous cycles were recorded, 85·4% of which had a mean oestrous cycle length (± S.E.) of 22·6 ± 0·9 days, while the average duration of oestrus (± S.E.) was 5·9 ± 0·2 h. Results showed significant differences between the mounts made by the teasers as well as mounts received by the heifer groups (both P = 0·01), but the teaser x heifer group interaction was not significant (P > 0·05). As all the heifers showed oestrus at least once, observation for oestrus between 06.00 and 18.00 hwould be reliable for supporting an artificial insemination scheme in the Guinea Savannah of Nigeria.
The dynamics of nitrogen uptake and its remobilization during the growth of sugar beet
Authors: Armstrong M. J. , Milford G. F. J. , Pocock T. O. , Last P. J. , Day W. 
Published: March 2009

SUMMARYThe uptake and distribution of N were examined in a series of sugar-beet crops grown on different sites (Broom's Barn, Suffolk and Trefloyne, Dyfed) or with 0 (No) or 125 kg N/ha (N125) between 1978 and 1982. Depletion of soil N was followed in some years. Initial rates of N uptake in spring for the N125 crops at Broom's Barn ranged from 2·3 kg/ha per day in 1980 to 5·8 kg/ha per day in 1981 and 1982 and at Trefloyne from 4·7 kg/ha per day in 1980 to 5·4 kg/ha per day in 1979. The initial phase of N uptake in No crops was shorter and at Broom's Barn the rate ranged from 1·6 kg/ha per day in 1979 to 5·1 kg/ha per day in 1982. Crops with high initial uptake rates had somewhat greater shoot N concentrations. There was no relation between the initial uptake rates or the total N uptake and the amounts of mineral N in the soil at the start of rapid growth in June. Simulations of early crop growth coupled with analysis of changes in the total N in the crop-plus-soil system showed that the rate of N uptake by the N125 crops was regulated by crop demand for N as determined by growth rate in 4 of the years and by soil supply in the 5th. The analysis of the crop-plus-soil N also showed that substantial losses of N occurred when the crop was actively growing in June and July in 1979 and 1980 due to excessive rainfall following early irrigations. There were serious consequences for N uptake, N concentration in developing leaves and the overall growth of these crops.N uptake rates in autumn ranged from no net uptake in 1979 and 1980 to 0·6 kg/ha per day in the other 3 years at Broom's Barn and 1·0 kg/ha per day at Trefloyne. Large amounts of N were remobilized from the shoot to sustain the growth of the storage root in years when uptakes from the soil in autumn were small. Remobilized N represented 80, 50 and 30% of the net increase in storage-root N between the end of August and harvest in 1979, 1980 and 1981 respectively. The amounts remobilized from shoots ranged from 8 to 18 kg N/ha and may therefore also represent a source of amino-N impurities in harvested beet. An analysis of N in individual leaves showed that remobilized N probably originated from leaf protein and that remobilization started at full expansion rather than at the onset of leaf senescence, which was often many weeks later.
Statistical analysis of two-dimensional variation in variety yield trials
Authors: Kempton R. A. , Seraphin J. C. , Sword A. M. 
Published: March 2009

SUMMARYMethods of adjustment for two-dimensional spatial heterogeneity of grain yield were investigated for 224 UK cereal trials. The methods used row and column ‘block’ analysis of plot yields and neighbour analysis based on first differences of plot yields. In 36% of trial analyses for block models and 30% for neighbour models the average variance of variety differences was reduced by more than 10% compared with the better of the one-dimensional row or column models. Compared with complete blocks, 2-D block analysis had a mean efficiency of 153% whereas the conventional 1-D block analysis (by rows) had a mean efficiency of 127%. Similarly, 2-D neighbour analysis had a mean efficiency of 159% whereas the 1-D analysis had a mean efficiency of 137%. Recently, general statistical methods have been developed for two-dimensional design and analysis; their wider use should lead to major gains in the precision of variety trials.
The course of fertilizer nitrogen uptake by rainfed sugarcane in Mauritius
Authors: Kwong K. F. Ng Kee , Deville J. 
Published: March 2009

SUMMARYThe patterns of N uptake and dry matter synthesis by sugarcane (Saccharum hybrid spp.) were studied at four locations in Mauritius with 15N–labelled ammonium sulphate (100 kg N/ha) applied either in a single dressing in September or in two split applications in September and the following February. More than 80% of the total N recovered at harvest (100–120 kgN/ha) was absorbed by the sugarcane during an active uptake period from October to January. Split application prolonged this active N uptake until April only and had no effect on dry matter accumulation. While total Nabsorbed by above-ground sugarcane showed no decline over time, 10–20 kg N/ha of the 15N–labelled N was lost from the green tops even when the N was applied on two occasions. The fertilizer N losses from above-ground sugarcane were, however, not evident when fertilizer N recovery with time was studied by the difference method. In view of the observed losses of fertilizer N from the aerial parts of sugarcane, measurement of fertilizer N recovery at harvest by the N isotope dilution technique underestimates fertilizer N uptake by sugarcane and attributes too large a fraction of N loss to denitrification/volatilization of NH3.
Changes in soil properties of a newly-cleared Ultisol due to establishment of hedgerow species in alley cropping systems
Authors: Hulugalle N. R. , Ndi J. N. 
Published: March 2009

SUMMARYThis study was initiated to evaluate the short-term (< 3 years) ability of some selected acid-soil adapted hedgerow species when planted in alley cropping systems to improve soil properties in a newly-cleared Ultisol (Typic Kandiudult) of southern Cameroon, 1990–92. The hedgerow species selected were Senna (Senna spectabilis), Flemingia (Flemingia congesta)and Acioa (Acioa barterii). A non-alley-cropped control was also included in the trial. The greatest quantities of prunings, and hence, mulch were produced by Senna and Flemingia. Exchangeable Ca, effective CEC and water infiltration were greatly increased in the alleys of plots where either Flemingia or Senna had been planted within 2·5 years of hedgerow establishment. The large amounts of mulch produced by Senna and Flemingia did, however, result in soil temperatures greater than those of the control or Acioa plotsc.1 year after application of the prunings as mulch. Root growth of Senna in the subsoil was significantly greater than that of either Acioa of Flemingia, but that of cassava was reduced by alley cropping with all three hedgerow species. Compared to the control or alley cropping with Acioa, maize and cassava yields were greater when alley cropped with either Flemingia or Senna hedgerows.
Comparison of meal and pellets for growing pigs fed either in troughs or off the floor
Authors: Braude R. , Rowell J. G. 
Published: March 2009

A co-ordinated trial has been carried out with fattening pigs at nineteen centres to compare the effects of the following methods of preparing and presenting the feed: (1) meal fed in the trough; (2) cubes fed in the trough; (3) meal fed off the floor; (4) cubes fed off the floor.Pigs fed meal off the floor had substantially worse growth rate and feed conversion than pigs on any of the other three treatments, probably because of feed wastage. With trough feeding, pigs fed cubes had slightly better growth rate and feed conversion than pigs fed meal. When the feed was given as cubes, there was little to choose between trough feeding and feeding off the floor. Faster growing pigs were slightly fatter and had slightly smaller eye muscles.
Critical concentrations of potassium in cotton (Gossypium hirsutum)
Authors: Singh D. , Brar M. S. , Brar A. S. 
Published: March 2009

SUMMARYPotassium concentrations in various plant parts of cotton (Gossypium hirsutum L.) at different growth stages were determined in field experiments in Punjab, India, in 1987, for plots fertilized at sowing and flowering, and these were compared with the final seed cotton yield. The optimum time of sampling for predicting relative yield depends on the time of K fertilizer application: if applied at sowing, plants should be sampled before the peak flowering stage (70 days after sowing, DAS); if applied at flowering (50 DAS), plants should be sampled 90–115 DAS. Critical K concentrations (% K. in dry matter) in the plant parts measured at different growth stages were 3·26 in the petioles of the third leaf from the top at flower initiation; 0·69 and 0·90 in blades and petioles of a lower leaf (first or second healthy leaf from the bottom of plant) respectively, and 2·60 in the petioles of the third leaf (young, fully mature leaf from the top of the plant) at peak flowering stage; 0·85 in blades of the third leaf, 0·53 and 0·50 in blades and petioles of a lower leaf, respectively, at the boll development stage; 0·70 and 2·85 in blades and petioles of the third leaf and 0·68 in petioles of a lower leaf at boll opening stage.
Maternal undernutrition during mid-pregnancy in sheep: variable effects on placental growth
Authors: McCrabb G. J. , Egan A. R. , Hosking B. J. 
Published: March 2009

SUMMARYThe effect of maternal undernutrition between the 30th and 96th day of pregnancy on placental growth in single-bearing ewes was determined separately in two experiments in consecutive years (1986 and 1987) at Mount Derrimut Field Station, Deer Park, Australia. In the first experiment, placental growth measured on the 96th day of pregnancy was reduced (473 v. 596 g) by maternal undernutrition, while in the second, placental growth was increased (600 v. 496 g). Foetal weight and its linear dimensions on the 96th day of pregnancy were not significantly affected by maternal u dernutrition in either experiment. The only significant difference in the animals and experimental conditions between the two studies was the liveweight of the ewes at mating, which wasc. 10 kg higher in the second experiment compared with the first (P< 0·01). Body condition score and the change in condition score during the respective nutritional treatments were not significantly different between the two experiments. The results suggest that maternal liveweight, possibly body reserves not quantifiable by condition score, protects and even enhances placental growth during a period of maternal undernutrition.