bluuebunny/crossref_metadata_2025_split huggingface dataset:
The nutritive value of diets containing different proportions of grass and heather (Calluna vulgaris L. Hull) to sheep
Authors: Milne J. A. , Bagley L. 
Published: March 2009

SummaryFive levels of frozen grass and heather (Calluna vulgaris, L. Hull) which contained 85% of the current season's shoots, were offered to five castrated male Scottish Blackface sheep per level. The levels of grass were 0, 200, 400, 600 and 800 g D.M./day, and heather was offered ad libitum after the grass had been eaten. Both the grass and heather were harvested in September. Voluntary intakes of heather increased by 0·46 g/g of additional organic matter intake (OMI) of grass between the two lowest levels of grass, but at higher levels of grass there was a highly significant (P < 0·001) linear decrease in OMI of heather of 0·57 g/g additional OMI of grass.No associative effects of grass (OM digestibility 70%) and heather (OM digestibility 44%) on OM or neutral-detergent fibre digestibility could be demonstrated. Intakes of digestible OM and nitrogen balance increased in a positive and linear manner with the proportion of grass in the diet. To meet the nitrogen and energy requirements for maintenance of the sheep the diet would require to contain 50% of grass. These findings are discussed in relation to the nutrition of sheep grazing heather-dominant moorlands.
A comparison of the sown swards of perennial ryegrass S. 24 and Italian ryegrass RvP in a two-year lamb production system, with different breeds of sheep
Authors: Newton J. E. , Young N. E. , Orr R. J. 
Published: March 2009

SummaryA comparison was made between an intensive system of lamb production based on Italian ryegrass RvP and one based on perennial ryegrass S. 24, over 2 years, each at three stocking rates (14, 17, 20 ewes/ha). More grass was grown in the first year than in the second when the yield of RvP was particularly reduced. The ewes and lambs ate more RvP than S. 24 but there was no difference in lamb growth rate. The lambs grew faster at the low stocking rate from 0 to 18 weeks and from 0 to slaughter than at the medium and high stocking rates, in both years. Ewe intake and lamb growth rate were higher in the second year than the first. The Masham ewes with two lambs ate significantly more grass per unit of body weight than the Finnish Landrace × Scottish Halfbred and Finnish Landrace × Scottish Blackface ewes, and their lambs grew significantly faster. It was concluded that for an intensive system of lamb production from grass, S. 24 was more suitable than RvP.
Fat deposition in Hereford and Friesian steers: 3. Growth efficiency and fat mobilization
Authors: Truscott T. G. , Wood J. D. , Gregory N. G. , Hart I. C. 
Published: March 2009

SUMMARYFood utilization in relation to growth of body components, and fat mobilization and its hormonal control in vivo, were examined in 15 Hereford and 15 Friesian steers which were slaughtered at 20 months of age. Changes in body composition between 6 and 20 months were calculated from the body composition of these animals and from an additional four and two steers from each breed slaughtered at 6 and 13 months of age, respectively.The Friesians consumed more food overall (14%) and grew more rapidly (14%), but their intake in relation to metabolic body weight was not different from that of the Herefords. Although the Friesians deposited more protein in relation to lipid there was no breed difference in food conversion ratio, and maintenance requirement relative to empty-body weight0·75 was estimated to be 7% greater in the Friesians than the Herefords. Friesians therefore had a lower efficiency of conversion of food energy to body energy. It is speculated that the higher maintenance requirement of the Friesians was due to a faster rate of protein deposition and a higher proportion of visceral organs with an associated higher rate of protein turnover.Changes in plasma concentrations of free fatty acids (FFA), insulin, growth hormone (GH), adrenaline and noradrenaline were examined in response to fasting at 12 and 20 months of age. Inaddition plasma concentrations of glucose, thyroxine (T4) and triiodothyronine (T3) were measured at 20 months of age.At both ages, FFA concentration increased almost linearly with duration of fasting and was not different between breeds. It was therefore unrelated to fat partitioning and a poor index of breed differences in metabolic and body type. Within breeds, the rate at which FFA concentration increased during fasting was correlated with estimated maintenance requirement (r = 0·53). This suggests a different relationship between FFA utilization and maintenance requirement in the two breeds.During fasting at 12 months of age, Friesians had higher concentrations of plasma GH and noradrenaline. At 20 months of age they had higher concentiations of glucose, insulin and catecholamines. There was no obvious hormonal explanation for the observed differences in body composition or growth efficiency. Correlations between indices of fat partitioning and maintenance requirement were low, suggesting no direct link between the two traits.
Effects of eight factors on the growth and nutrient uptake of winter wheat and on the incidence of pests and diseases
Authors: Prew R. D. , Church B. M. , Dewar A. M. , Lacey J. , Penny A. , Plumb R. T. , Thorne Gillian N. , Todd A. D. , Williams T. D. 
Published: March 2009

SUMMARYA multifactorial experiment sown to winter wheat cv. Hustler in autumn 1978 tested the effects of combinations of the following eight factors, each at two levels: drill type, sowing date, amount of nitrogen, division of nitrogen, irrigation, autumn pesticide (aldicarb), summer aphicide (pirimicarb), and fungicide (carbendazim, maneb and tridemorph).The mean grain yield of all plots was 9·7 t/ha and the best eight-plot treatment mean was 11·3 t/ha. The factors that had the greatest effect on yield were aphicide and fungicide, mainly from the control of Metopolophium dirhodum and Septoria spp. respectively. Both factors increased grain size and their effects were more than additive and greater with 250 than with 160 kg N/ha. Aphicide and fungicide also temporarily decreased the numbers of microbes on the developing ears. Autumn pesticide gave good control of aphids in the winter and some control in the summer: it also decreased nematode populations and slightly increased yields.Precision sowing compared with random distribution of seeds along the row had little effect on growth or yield. Sowing on 21 September compared with 13 October greatly increased growth early in the season but had less effect after anthesis; it was the only factor that increased yield when aphicide and fungicide were applied. There was negligible infection by barley yellow dwarf virus in crops sown on either date. The amount and division of N fertilizer affected N uptake early in the season and had small effects on the production and survival of tillers. Three N applications instead of one slightly increased grain yields but did not affect total N uptake by grains plus straw, which averaged 190 kg N/ha. The larger amount of N always increased N uptake but decreased yield in the absence of aphicide and fungicide. Irrigation slightly decreased yield despite prolonging the duration of green leaf area.
Comparative analysis of the growth, development and yield of three soya-bean varieties (Glycine max L.)
Authors: Tayo T. O. 
Published: March 2009

SUMMARYThe growth, development and yield of three soya-bean varieties, Hampton, Kent and CNS, were compared in two field experiments during 1974 and 1975 in Nigeria. The results, which were similar for both years, showed that the varieties differed significantly in the order Hampton > Kent > CNS for the development per plant of leaf area, number of branches, number of nodes, number of mature pods, number of seeds, pod and seed yields, husk dry weight and seed to husk ratio as well as seed yield per hectare. The differences between the varieties in seed yield could be genetic but leaf area development seems important as well. Hampton therefore appears to have the potential for high seed yield under the prevailing local conditions.
Performance of growing pigs fed dried microbial cells (Methylomonas methylotropha)
Authors: Whittemore C. T. , Moffat I. W. 
Published: March 2009

SUMMARYIn two experiments, 192 individually penned pigs were given diets containing 900 g barley/kg together with either 100 g dried microbial cells (DMC)/kg or 100 g white fish meal (WFM)/kg, and grown from 23 to 60 kg live weight. In Expt 1 rationing was by live weight and there was no difference between diets for feed used or live weight gained. In Expt 2, pigs were rationed by time and those fed diet DMC grew 15 g/day slower than those fed diet WFM, and their carcasses were of lower specific gravity.
Magnesium metabolism in the dairy cow. I. Metabolism on stall rations
Authors: Rook J. A. F. , Balch C. C. , Line C. 
Published: March 2009

1. The results are reported of a series of 8-day magnesium metabolism trials carried out with milking cows fed a variety of typical winter stall rations.2. Twelve cows fed a standard ration of 15 lb. hay plus 12 lb. of a concentrate mixture containing 3 parts dredge corn, 1 part bran, 1 part decorticated groundnut meal and 1 lb./cwt. Churn 105 minerals, showed variations in the proportion of the feed magnesium excreted in the faeces of from 66·53 to 76·98%, probably reflecting individual differences in the capacity of animals to absorb magnesium.3. Wide differences in the utilization of the magnesium in typical winter rations were observed. Mean values, with a standard error, obtained for the proportion of the feed magnesium excreted in the faeces with various types of ration were as follows: hay plus concentrates, 71·48 ± 0·94; hay plus proprietary dairy cubes, 62·15 ± 2·73%; hay, proprietary dairy cubes plus decorticated groundnut meal, 91·98 ± 1·93%; hay, silage (1) plus concentrates, 79·53 ± 0·99%; hay, silage (2) plus concentrates, 74·07 ± 4·24%; hay, mangolds plus concentrates, 74·28 ± 5·91%.
Hairiness in wool and a method for selection based on the nature of the fibres and the distribution of halo hairs of the lamb's tail
Authors: Labban F. M. 
Published: March 2009

Hairiness in wool of Suffolk sheep as a fault was found to be associated with other defects like coarseness of wool fibres, hairiness of the britch, and the occurrence of pigmented fibres. The presence of these various defects was studied in the lamb's tail at docking time, and subsequently evaluated and correlated with the fleece.The tails were graded according to the nature of the fibres and the spread of halo hairs from the tip to the base into four principal grades which by further subgrading could be made into seven grades. The results were as follows:(1) There was wide variability in grades of tails within each flock.(2) Average grade of tails followed in general the mean quality of the adult fleece.(3) When Border Leicester were crossed with Welsh Mountain the tails of the two reciprocal crosses were found to be of hairy type of tail and nearly like the Welsh Mountain type.(4) The percentage of coloured tails in the least hairy grades was found to be inversely related to the quality of the tail grade and indirectly to the fleece quality.(5) The diameter of the wool fibres on the base of the tail is highly correlated with the diameter of fibres from the britch regions or mean fibre diameter from four regions of the body (mid-shoulder, midside, hip and britch).(6) The mean diameter of the wool fibres obtained from four different parts of the tail was correlated with those of the britch regions only.(7) The diameter and variability of fibres increased from shoulder to britch in the body and from base to tip in the tails.(8) The britch and tails of two groups of sheep, one group characterized by coarse and the other by fine britch and tail wool, were studied histologically. There were significant or highly significant differences in the following characteristics in the britch of the two groups: (a) total number of follicles, (b) primary follicles with no medulla, (c) total number of secondary follicles, (d) secondaries with no medulla, (e) secondaries with large medulla. The only type of follicle where a significant difference was found in the tail was in the number of secondary follicles with no medulla.
Nutrient relations of winter wheat:3. Nitrogen uptake, photosynthesis of flag leaves and translocation of nitrogen to grain
Authors: Gregory P. J. , Marshall B. , Biscoe P. V. 
Published: March 2009

SUMMARYTwo years with contrasting weather, 1976 and 1977, were used to investigate the effects of nitrogen fertilizer on the uptake of nitrogen by crops of winter wheat and on the rate of photosynthesis of flag leaves. The studies involved a number of crops which received various amounts of nitrogen fertilizer at various stages of growth. Weekly measurements were made of the amount of nitrogen in the crops and its distribution within the plant, while a mobile gas exchange system measured the photosynthesis of individual flag leaves.While the treatments imposed in 1976 resulted in different concentrations of nitrogen in the flag leaves, the maximum rate of photosynthesis and its efficiency in dull light were both unaffected when leaves of the same age were compared. The 2 years gave contrasting results in terms of the amounts of nitrogen taken up during grain growth: in the very dry summer of 1976 it could account for only 25% of the nitrogen in the ear at harvest while in 1977 it could account for almost 50%. These different amounts of translocation to the grain were accompanied by different photosynthetic behaviours of the flag leaves and our analysis shows that, in all treatments, the maximum rate of photosynthesis after anthesis was related to the fractional loss of nitrogen from the leaves.The implications of these results for farming practice and for techniques used to investigate the effects of nitrogen on photosynthesis are discussed.
The relations between the main shoot and tillers in barley plants
Authors: Kirby E. J. M. , Jones H. G. 
Published: March 2009

SUMMARYBarley plants normally produce some tillers which die at an early stage, without bearing an ear. To investigate the proposition that these non-ear-bearing tillers may be wasteful of plant resources, two experiments were made in which the effect of tiller growth on the growth and final size of the main shoot was assessed. In one experiment, tillers were removed at a very early stage when they were a few mm long, or later when they were just emerging from the subtending leaf sheath. In the other experiment the main shoot was removed from the embryo and the size of the coleoptile tiller which grew in its absence was measured.Tiller removal affected the growth and final size of the main shoot. Leaves emerged more quickly on the main shoot of the detillered plants and were bigger and sometimes more in number. The main shoot of the detillered plants was heavier and it bore a greater weight of grain because the ear had more and heavier grains. In the experiments where the main shoot was removed the coleoptile tiller produced more leaves, which emerged more rapidly and it bore more grains than the coleoptile tiller of the intact plants.It is concluded that tillers, during their initiation and early growth, compete with the main shoot for a limited supply of resources, thus reducing the size of the main shoot. As some of the resources of the plant are used to produce tillers which die at an early stage and make no contribution to the final grain yield, it appears that they should be regarded as wasteful and that their production may reduce the final grain yield. The physiology of the initiation, growth and early death of these non-ear-bearing tillers requires further investigation.
Competition studies in diploid and tetraploid varieties of Lolium perenne: 1. The influence of density and proportion of sowing
Authors: Norrington-Davies J. , Harries J. H. 
Published: March 2009

SUMMARYTwo varieties of Lolium perenne, the diploid Hora and the tetraploid Terhoy were sown either as a pure stand or as a binary mixture on to the surface of multipots filled with a standard John Innes compost. Density of sowing was varied over the range of 16, 24, 36, 50 and 100 seeds/pot. There were four replicates. The pattern of germination was followed over a period of 14 days when it was found that (i) the varieties did not differ in their germination when grown alone, but in mixtures the diploid was slower to germinate than the tetraploid, (ii) as the density of sowing per pot was increased, the mean germination time (MGT) was increased, and (iii) the final germination of both verities decreased with increasing density.In a second experiment the same procedures were followed as before but seed of each variety was sown either as a pure stand or in a mixture of varying proportion as follows: 100:0, 75:25, 50:50, 25:75, 0:100.The results showed that (i) the diploid had the fastest MGT whilst the mixture values showed no significant variation, and (ii) the final germination percentage of the diploid decreased relative to its pure stand value as its proportion in mixtures decreased, whilst the tetraploid under the same circumstances increased relative to its pure stand value.It is suggested that differences such as those found could be explained by the presence of germination inhibitors in the seed coats of the two ryegrass varieties.
Food-intake level in some Romney Marsh ewes and follicle-group development in their progeny
Authors: Wildman A. B. 
Published: March 2009

1. An experiment was carried out in which twelve Romney Marsh ewes were separated into two groups, one kept on a high plane of food intake and one on a low plane during pregnancy and lactation. Skin and wool samples were taken from the progeny at birth and weaning; the ratio Sf/Pf was determined for these ages as well as the proportion of follicles of various kinds and in different phases of activity. The results are compared with those of Ryder from an earlier experiment with Cheviots.2. Differences in food intake of ewes of the order described affected live weight at weaning, but did not significantly affect the differentiation and development of secondary follicles in the foetus nor their number at weaning.3. Lambs in the low-plane group shed secondary fibres at 12 months old much more than those which had been in the high-plane group.4. A partial association of variation in birth Sf/Pf with variation in birth weight was demonstrated, but more than half the variation in this ratio is not accounted for in this way, and the same applies to the variation in birth S/P of the Cheviots in Ryder's earlier experiment. It is suggested that variations in foetal environment and in the early post-natal period affect the rate at which the secondary follicle population in a lamb develops towards its mature genetic maximum.
The performance of sheep with differing haemoglobin and potassium blood types
Authors: King J. W. B. , Evans J. V. , Harris H. , Warren F. L. 
Published: March 2009

1. Records of sheep with differing haemoglobin and potassium blood types were examined in a large flock of Scottish Blackface sheep.2. Differences in reproductive performance, which would be subject to natural selection, and in growth rate, fleece characteristics, etc., which would be subject to artificial selection, were sought as an explanation for the gene frequencies observed in different breeds.3. No significant differences were found in any weights or measurements.4. The number of lambs produced by different types of ewe did not differ significantly, although there was some suggestion that haemoglobin heterozygotes produce a larger number of lambs at weaning.5. Study of the equilibrium of the population, however, showed that any heterozygote advantage, if it exists at all, can only be small.
A study of growth in swards of timothy and meadow fescue. I. Uninterrupted growth
Authors: Langer R. H. M. 
Published: March 2009

1. Swards of S. 48 timothy and S. 215 meadow fescue growing alone or together were sampled at intervals of 3 weeks throughout the season. The number and weight of leaves, stems and ears were determined, and leaf area was estimated.2. Despite high rainfall, the total number of tillers in both species declined from the beginning of the experiment until early July, but increased again from then onwards until the original complement had been approximately restored. The number of leaves failed to show a corresponding increase in the autumn because each tiller carried fewer leaves than earlier in the year.3. In the spring total dry weight increased more rapidly in meadow fescue than in timothy which in turn out-yielded meadow fescue later in the season. Both species attained their greatest dry weight soon after ear emergence, a period which was marked by considerable crop growth and relative growth rates.4. Leaf area index reached a maximum before total dry weight had increased to its highest level, but then declined in both species. Meadow fescue differed from timothy by producing a second crop of foliage after the summer with a leaf area index of about 7. This second rise appeared to be due mainly to increased leaf size in contrast to timothy whose leaves became progressively smaller towards the end of the season.5. The differences in growth between the species discussed with reference to their dates of ear emergence which in this experiment differed by about 6 weeks.
Variability of yields in cereal variety × fungicide trials
Authors: Mycroft Hilary 
Published: March 2009

SUMMARYYield variability of spring barley and winter wheat varieties is investigated in National Institute of Agricultural Botany trials sown to assess the influence on varieties of fungicide treatment. The extent of the variation in relative variety performance due to years and centres is estimated for untreated and treated yields and for yield response to fungicide. The consequences for the design of future trials systems are considered.
The effects of breed, breeding system and other factors on lamb mortality: 2. Factors influencing the incidence of delayed birth, dystokia, congenital defects and miscellaneous causes of early death
Authors: Woolliams Carol , Wiener G. , Macleod N. S. M. 
Published: March 2009

SUMMARYThe incidence of a number of causes of death of lambs around the time of birth was examined in relation to breed, inbreeding, birth weight, birth type, sex of lamb, week of birth and parity. Data were from a grazing flock on an upland farm over a 6-year period. The breeds were the Scottish Blackface, Cheviot, and Welsh Mountain and the crosses among them. Each breed and cross was maintained at five levels of inbreeding ranging from zero to 59% inbreeding coefficient.The incidence of delayed birth varied significantly among the breeds and crosses with the Welsh having the lowest incidence. Compared with the pure breeds the crosses showed a lower incidence of both delayed birth and preparturient deaths, but significantly only for the latter.Dystokia was classified according to whether it arose from the relative dimensions of lamb and dam or from malpresentation. For both types the heaviest lambs had the highest incidence but the association with birth weight was much stronger for dystokia involving dimensions. Breed variation was not significant, but cross-breds had the highest frequency for the dimensions category and the lowest for malpresentation. Singles were at greater risk than twins as were lambs born to a first parity.Congenital defects as a cause of death were divided into six categories. Only skeletal defects varied significantly among breeds and the incidence increased with inbreeding, but crosses of inbred lines did not have the lowest frequency. For congenital defects overall and for hydrocephalus and hydronephrosis in particular, line crosses (noninbred) had the lowest incidence and 25% inbred lambs the highest, the frequency declining with further inbreeding. None of the other factors considered affected variation in the incidence of any of these defects to a significant extent.Liver rupture and brain haemorrhage were most frequent in heavy lambs, singles and lambs born to a first parity dam.