bluuebunny/crossref_metadata_2025_split huggingface dataset:
The grazing behaviour and free-water intake of East African shorthorned zebu heifers at Serere, Uganda
Authors: Wilson P. N. 
Published: March 2009

1. Results are presented which refer to the behaviour of twenty young East African shorthorned zebu heifers grazing a Chloris gayana ley at Serere Experiment Station in north-east Uganda. The heifers were studied for two trial periods, each of 72 hr. duration, one during the transitional season and one during the dry season.2. Five of the heifers were recorded individually, and the results showed a fair degree of variation in behaviour between heifers. The difference in total ruminating time between two heifers was statistically significant, but all other differences were nonsignificant.3. The day to day variation in behaviour was very small. There was no significant difference in the time spent engaged in any major activity between the 3 days of either trial.4. During the transitional period of the year between the wet and dry seasons, young heifers spent 8·6 hr. grazing (22·5% at night; 77·5% by day) and 7·0 hr. ruminating out of a 24 hr. period. During the dry season, the heifers spent 7·8 hr. grazing (25·2% at night; 74·8% by day) and 6·5 hr. ruminating. There were no other important differences in behaviour time between the two seasons.5. In the transitional season the grazing was divided into three distinct periods, two during the day and one at night. In the dry season the afternoon grazing period was divided by a short resting period into two parts, making four periods in every 24 hr. An average of 2 hr. were spent night-grazing in both seasons, and this night grazing was independent of moonlight.
The fleece of the Scottish Blackface sheep I. Seasonal changes in wool production and fleece structure
Authors: Doney J. M. , Smith W. F. 
Published: March 2009

1. Seasonal changes in wool production per unit area of unstretched skin, number of fibres of each type per unit area, ratio of fibre types, mean fibre weights, lengths and diameters and degree of medullation are given. The production cycle shows a peak in August and September and a trough in February and March, the weight of wool produced in the latter period being only 16% of that in the former. Approximately 80% of the fleece is produced in the 6 months from June to November (lambing ewes). Other components show similar trends.2. The production cycle does not entirely coincide with the nutritional cycle as estimated from bodyweight changes before late pregnancy. Whilst bodyweight increases from September to November wool production declines by about 25%.3. The winter drop in wool production per unit area is caused partly by a decrease in the mean weight of each fibre type (in turn made up of a decrease in both length and diameter) and partly by a 50% reduction in the number of active fine fibre follicles and a 100% reduction in active kemp follicles. There is no apparent change in the number of active coarse fibre follicles. The degree of medullation of both coarse and fine fibres declines substantially between December and May.
The effect of sodium and potassium fertilizer on the mineral composition of sugar beet
Authors: Adams S. N. 
Published: March 2009

Plants from salt and potash fertilizer trials at Bothamsted were harvested at intervals throughout the growing seasons of 1942 and 1943 and analysed for N, K, Na, Ca, Mg and Mn.The uptake of nutrients is discussed with respect to field methods of fertilizer application.Salt increased beet yield in both years, but it did not act by mobilizing soil potassium reserves and increasing the potassium status of the plant. Potash fertilizer, although increasing the potassium status of the plant, did not increase yield. Sodium and potassium were differently distributed in the plant. At harvest, only 6% of the plant's sodium content was in the root compared with 33% of the potassium. The potassium, but not the sodium content of the petiole, was higher than that of the lamina until the end of August. Sodium thus is a nutrient for beet and not a potassium substitute.
Studies of the effects of soil aggregate size on the emergence and growth of beet (Beta vulgaris L.) II. Leaf development
Authors: Hammerton John L. 
Published: March 2009

Seedling beet plants grown on a fine soil separate produced more and larger leaves than those grown on coarser separates. This result has been ascribed to the greater quantity of available water, and the better root-soil water contact, in the fine separate compared with the others. Difficulties of root establishment in the coarser separates may retard the start of leaf development relative to that in the fine separates. Soil separates also affected leaf number, in some experiments, through their effect on seedling emergence, in that rapid emergence gave seedlings a slightly longer period for leaf production.Fodder beet plants (variety Red Otofte) had a greater leaf number per plant at all counts than plants of any of the sugar-beet strains grown. Polyploid sugar-beet seedlings had larger leaves than diploid seedling.Nitrogen applications to the seed-bed did not stimulate leaf production. In one instance, heavy fertilizerdressingsretardedleafproduction,probably by an osmotic effect.
The response of pastures in Northern Ireland to N, P and K fertilizers and to animal slurries: III. Effects in experiments continued for either two or three years
Authors: Adams S. N. 
Published: March 2009

SUMMARYThree factorial experiments made in 1969 on Northern Ireland pastures to measure effects upon yield and mineral content of 0, 180 and 360 kg N, 0, 30 or 60 kg P and 0, 150 or 300 kg K/ha/year, both with and without 1380001 slurry/ha, were continued on the same sites with the same treatments in 1970 and two of them were continued again in 1971.Responses to nitrogen in the second and third seasons were similar to those of the first season. There was no evidence that large nitrogen dressings plus slurry were causing nitrogen to accumulate in the soil.Repeated cutting of herbage given neither fertilizer potassium nor slurry was beginning to reduce both yield and the potassium content of the herbage in the second and third years. Giving fertilizer potassium prevented these losses, but the potassium in the slurries was less effective because it did not maintain the potassium content of the herbage. Reasons for, and implications of this effect are discussed.There was no evidence that soil phosphorus reserves were becoming depleted, when judged by the % P in herbage receiving neither fertilizer nor slurry even after the herbage had been cut and removed for two or three years. As there was no immediate need for fertilizer phosphorus, the P in the slurries, even though slower acting than that in mineral fertilizers, seemed suitable for maintaining the phosphorus status of these pasture soils.
Individuality and heritability of the blood composition of calves with particular reference to the selection of stock with improved growth potential
Authors: Rowlands G. J. , Payne J. M. , Dew Sally M. , Manston R. 
Published: March 2009

SUMMARYBlood samples, taken from each of 231 calves on three occasions at 9,10 and 11 weeks of age, were analysed for packed cell volume, blood glucose and Hb; and serum albumin, urea nitrogen, total protein, Ca, inorganic phosphate, Mg, K, Na and Cu. Differences in the blood composition for individual calves were demonstrated for all blood constituents (P < 0·01) with variations among calves proportionally largest for albumin and smallest for sodium. Concentrations of glucose, Hb and K were inherited (heritability estimates > 0·4).There were significant correlations (P < 0·001) between the calves' growth rates from 1 to 12 weeks and the concentrations of each of the blood constituents, glucose Hb, K, Na, albumin and inorganic phosphate; in the cases of Na and albumin, comparison of the blood analysis at 9–11 weeks with body weights at 6 and 9 months showed that these correlations persisted, and that by 9 months differences in concentrations of Na and albumin among individuals were associated with anaveragedifference of as much as 55 kg in body weight.The evidence that concentrations of certain blood constituents are both inherited and related to growth rate suggests that not only might calves be screened early in life for indications of rapid growth rate, but also that animals might be bred to have the blood characteristics indicative of this quality.
Distribution of red cell potassium and evidence of its genetic control in buffaloes
Authors: Sengupta B. P. 
Published: March 2009

SUMMARYDistribution of red cell potassium in buffaloes and its possible genetic control was investigated. The mean values of red cell K+ varied between 37 and 41 m-equiv/l in LK type animals and between 87 and 91 m-equiv/l in the HK type. Red cell K+ concentration within individual animals of either LK or HK type was fairly stable over successive samplings, whereas the same values among animals within a type varied rather widely. The inheritance of red cell K+ type in buffaloes appeared to be controlled by a single pair of genes. HK animals were homozygous for the recessive allele while LK animals represented the heterozygotes and also the homozygotes for the other allele. In addition, there was indication that the gene responsible for LK phenotypes might not be completely dominant over the recessive allele. The three populations of buffaloes examined were found to be in genetic equilibrium in respect of red cell K+ polymorphism. HK animals predominated in both the breeds, the frequency of the recessive gene (h) being 0·78 and 0·74 for the Murrah and Bhadawari breeds respectively.
Growth and yield of highland maize in Mexico
Authors: Goldsworthy P. R. , Colegrove M. 
Published: March 2009

SUMMARYThe growth and yield of five highland varieties of tropical maize were studied. Grain yields were between 4·7 and 8·8 t/ha. Crop growth rates (C) increased to a maximum of between 25 and 35 g/m2/day at silking and then declined. Grain growth rates (maximum 21 g/m2/day) exceeded current C during most of the grain-filling period.After silking, when C exceeded grain growth rate, dry matter accumulated in the stem and husk, resulting in an increase of from 200 to 600 g/m2. Later, as grain growth rate increased and exceeded current C, some of this accumulated material was incorporated into the grain, and stem weight decreased. A comparison of the dry weight changes after flowering in these varieties with those reported for a hybrid that yielded 12 t grain/ha indicates that the smaller yield of the Mexican varieties was associated with smaller grain growth rates and the incorporation into the grain of a smaller fraction of the dry weight produced after flowering. These results suggest that the capacity of the grain ‘sink’ to utilize assimilates limited yields in the tropical varieties.
Linear programming and the optimum carrying capacity of range under common use
Authors: Connolly J. 
Published: March 2009

SUMMARYThe common use of range by different types of animals may be more efficient than separate grazing by each type in that they may be complementary in their utilization of forage. Also, under certain pasture and range conditions the danger of permanent damage by over-grazing can be critical. This paper presents a method of assessing the optimum carrying capacity of range under single or common use subject to constraints on the level of utilization of forage plants. The joint optimum carrying capacity for the animal types may vary as the management objective varies between maximum profit, maximum animal gain or maximum utilization of forage, all subject to the same protection against over-grazing.
The constancy of the digested cell wall in grass
Authors: Moir K. W. 
Published: March 2009

SUMMARYThe quantity of in vitro digested cell wall was determined in the separated leaf and stem of Digitaria decumbens (pangola grass) fertilized at three different levels of nitrogen and cut after two different periods of regrowth. The treatment means ranged from 39·6 to 41·5 g digested cell wall per 100 g forage organic matter in leaf, and from 37·5 to 41·6 g in stem. For both leaf and stem the lowest mean amounts of digested cell wall were associated with the highest levels of fertilizer and the longer periods of regrowth. The results for nitrogen fertilizer were consistent with those from previous in vivo digestibility experiments, but when the effect of the total cell wall on digested cell wall was taken into account there were inconsistencies. The previous in vivo digestibility data were used in conjunction with the present results in support of a view that interpretation of digestibility data for grasses is best made by reference to a constant digested cell wall of 39·5 g/100 g forage organic matter.
Delayed nitrification and controlled recovery of aqueous ammonia injected under grass
Authors: Ashworth J. , Flint R. C. 
Published: March 2009

SUMMARYNitrification of aqueous ammonia, and its uptake by grass, are slower when the amount of NH3-N injected per unit length of slit is increased and as a result crop yield is spread more evenly over the growing season. Measurements of the amounts of NH4-, NO3- and NO2-N in the soil, made at intervals from February until October, and computed diagrams showing their distribution in soil under grass, are presented. We conclude that, at average current rates of application, most of the aqueous ammonia used for grass in England and Wales is probably not applied along the injection slit in sufficient quantity to allow it to persist throughout the summer.
Fat cell size in Pietrain and Large White pigs
Authors: Wood J. D. , Enser M. B. , Restall D. J. 
Published: March 2009

SUMMARYIn view of the dependence of fat metabolism on the size of fat cells and the lack of information describing the change in fat cell size which occurs during growth in pigs, an examination was made of the size of subcutaneous fat cells in Pietrain and Large White pigs of 30–95 kg live weight. A microscopic procedure was used and fat cell diameter was measured at two levels in the outer layer of shoulder fat and at two levels in the inner layer.In both breeds the rate at which cell diameter increased in size with live weight was greater in the inner layer than the outer layer. At all levels this rate of increase was greater in Pietrains. At the two levels in the inner layer the cells from Pietrains increased in size by 41% and 54% between 30 and 95 kg live weight and the cells from Large Whites increased in size by 23% and 36%. The result was that at 95 kg live weight both breeds had cells of similar size in the inner layer.Therefore in pigs of the same live weight, cell size varies, depending on the site at which the examination is made and the breed of pig. Even at constant cell size, however, the lipogenic capacity of the fat from different levels and different breeds must be different since the cells increase in size at different rates.
The transpiration of Mexipak wheat (Triticum aestiviumL.) in central Iraq
Authors: Al-Nakshabandi G. A. , Ismail H. N. 
Published: March 2009

SUMMARYThe actual transpiration of Mexipak wheat (Triticum aestiviumL.) was determined by the inflow-outflow method and by soil moisture determination by the use of a neutron probe and gravimetrically. Three irrigation treatments were used during the 1969 season, wet, medium and dry. Amounts of water given were 370, 310 and 255 mm for wet, medium and dry treatments respectively. One irrigation treatment was used during the 1971 and 1972 seasons in which 620 and 700 mm of water respectively was given. However, during the 1973 season, two wet irrigation treatments of 560 and 670 mm of water were used. Values ofEtmeasured by different methods were closely related. Seasonal averages ofEtwere 2·55, 1·99 and 1·62 mm/day for wet, medium and dry treatments respectively. The empirical coefficient (f = Et/Eo) under wet treatment, was found to be higher than that given by Penman (1956) for short grasses and higher than that obtained by Boumanset al.(1963) for wheat and barley in Iraq. The empirical coefficientKbin the Blaney-Criddle formula was less than the value given by Blaney & Criddle (1950) for an arid climate and less than the value obtained by Boumanset al.(1963) for wheat in Iraq. The water use efficiency for grain production was greater under dry than under wet treatment.
The relationship between productivity and some components of canopy structure in ryegrass (Lolium spp.): IV. Canopy characters and their relationship with sward yields in some intra population selections
Authors: Rhodes I. 
Published: March 2009

SUMMARYStudies were carried out to measure the productivity of selections for extreme expression of the various components of canopy structure from within six Lolium populations of contrasting morphology.Considerable variation existed for all canopy characters within each base population and this was reflected in the difference between the high and low selections.In the first harvest year productivity was closely positively correlated with leaf length. Although some significant differences in yield occurred between selections for other characters, no general pattern was evident as with leaf length. Within the base populations differences in yield occurred between selections of similar leaf length, emphasizing the role of other physiological factors in controlling yield.In general, dry-matter production was greater in the first harvest year than in the second harvest year. In the second year the long-leaved selections from L. multiflorum and L. multiflorum × L. perenne continued to produce greater yields than their respective short-leaved selections and base populations, but no such differences were evident in L. perenne S. 23 and S. 23 × Ba 6280. Whilst long-leaved selections from the former group were as persistent, or even more persistent than their base populations, the long-leaved selections from L. perenne S. 23 and S. 23 × Ba 6280 showed a lower persistency. Similarly, whilst erect tiller selections from L. multiflorum and L. multiflorum × L. perenne were as or more persistent than their base populations, the three L. perenne erect tiller selections exhibited reduced persistency.The plant breeding implications of these results are discussed.
The utilization of maize silage for intensive beef production: I. The effect of level and source of supplementary nitrogen on the utilization of maize silage by cattle of different ages
Authors: Thomas C. , Wilkinson J. M. , Tayler J. C. 
Published: March 2009

SUMMARYFifty-four British Friesian castrated male calves, initially 3, 6 or 9 months of age (107, 180 and 249 kg initial live weight, respectively), were individually fed for 83 days on maize silage (27·9% dry matter (D.M.), 10·7% crude protein in D.M.), offeredad libitum. Silage was offered either alone or supplemented with cobs of dried lucerne (21% of total D.M. intake). Three levels of urea (0, 1 and 2% of silage D.M.) were added to the silage before feeding.Total D.M. intakes averaged 23·0, 23·4 and 21·6 g/kg live weight (LW) for the 3-, 6- and 9-month-old animals, respectively. Addition of urea increased silage intake by 11% in the 6-month-old group but there was little effect in the 3- and 9-month-old groups. Lucerne supplementation reduced silage D.M. intake from 22·0 to 18·4 g/kg LW (P< 0·001) and increased total D.M. intake by 1·4 g/kg LW (P< 0·001).Live-weight gain (LWG) of the cattle fed on silage alone increased (P< 0·001) with increasing age of animal. The main effect of urea was to elevate (P< 0·001) LWG from an average of 0·79 (no urea) to 0·94 kg/head/day (2% urea). However, it appeared that most of this effect was confined to the 6-month-old group. The effect of lucerne on LWG decreased with increasing age of animal (P< 0·001). Inclusion of lucerne in the diet significantly reduced the response to urea (P< 0·05).Feed conversion efficiency (LWG/100 Mcal DE intake) decreased (P< 0·01) with increasing age of animal but increased with urea addition from an average of 4·7 (no urea) to 5·3 kg LWG/100 Meal DE intake (2% urea). The response to lucerne supplementation in terms of efficiency was greatest in the 3-month-old group and thereafter declined markedly with increasing age of animal.The results of this experiment indicated that cattle older than 6 months of age (180 kg LW) could achieve a rate of growth of 1·0 kg/head/day on maize silage supplemented solely with urea, but that younger animals required supplementary lucerne to support a high rate of live-weight gain.
The feeding value of mixtures of alkali-treated straw and grass silage
Authors: Terry R. A. , Spooner M. C. , Osbourn D. F. 
Published: March 2009

SUMMARYThe digestibility and intake by sheep of a neutral mixture of alkali-treated straw and grass silage was compared with an all-silage diet, mixtures of treated straw and silage adjusted to pH of 4 and 10 and with mixtures of untreated straw and silage. Treatment of the straw with alkali increased the digestibility of the organic matter from 46% to 68%. The daily intake of dry matter and digestible organic matter of the neutral, treated-straw/silage mixture was 24·1 and 15·0 compared with 14·7 and 8·8 g/kg live weight for the untreated straw/silage mixture. The sheep when fed ad libitum ate more of the neutral mixture than they did of the mixtures made acid (pH 4·0) and alkaline (pH 10·0) or of the grass silage although the differences were not significant. Calves were fed similar diets of grass silage, a neutral mixture of treated straw and silage and treated straw and grass silage offered without premixing. The calves offered the neutral mixture ate 16·0% more dry matter and 14·5% more organic matter than did the calves offered either silage alone or the unmixed diet and gained live weight at the rate of 0·42 kg/head/day compared with 0·44 for the silage alone and 0·37 for the unmixed diet.
Methods of analysis of a competition diallel in Italian ryegrass with varying mixture proportions
Authors: Wright A. J. 
Published: March 2009

SUMMARYTwo methods of analysis of variance of experiments involving diallel arrangements of binary mixtures and monocultures where the former are each represented by a linear replacement series (de Wit, 1960) to detect mean quadratic and quartic patterns among the monocultures and different mixture types, and array differences with respect to linear, quadratic, cubic and quartic effects are given. These are applied to data from an experiment on Italian ryegrass where the four varieties 1145 and S. 22 (diploid), IG2 and Tetila (tetraploid) are mixed in the proportions 75:25, 50:50 and 25:75.Significant mean quadratic effects for D.M. yield at certain harvests are due to higher yields from monocultures than mixtures, and a mean quartic effect at one harvest reflects a lower yield from 75:25 mixtures than 50:50 mixtures or monocultures. Array differences for linear and quadratic effects are largely a property of the ploidy contrast. Specific mixture effects were recognized for two varietal combinations, mixtures between the two tetraploid varieties showing some yield depression, and those between the two commercial varieties (RvP and Tetila) a considerable increase. No meaningful significant effects were detected for in vitro digestibility.Further analysis of total D.M. yield by means of the regression of array covariance (Wr) on to array variance (Vr) show, as expected, a closer relationship of Wr and Vr with the non-recurrent component at a frequency of 75% than at 50% or 25%, but the significant departure of the slope from unity is interpreted as evidence that no reliable information as to the relative competitive abilities of the varieties can be obtained from these statistics. Examination of the de Wit replacement graphs strongly suggests a ranking of competitive ability which accords with the known morphology of the varieties.