bluuebunny/crossref_metadata_2025_split huggingface dataset:
Results of an experiment at Rothamsted testing farmyard manure and N, P and K fertilizers on five arable crops I. Yields
Authors: Widdowson F. V. , Penny A. , Cooke G. W. 
Published: March 2009

1. A ‘reference plot’ rotation experiment was begun at Rothamsted in 1956 on a field where grass had grown for many years. The soil contained very little HCl-soluble P and K but much N. The soil had been acid, but was limed to pH 6·5 immediately before the experiment started; this pH has been maintained. Very small individual plots (0·00128 acre) were used and nearly all work was done by hand. The results showed that such small plots can be used to do complicated rotation experiments satisfactorily provided that all work is done carefully and movement of soil over plot boundaries is prevented.2. Responses to combinations of N, P and K fertilizers and farmyard manure (FYM) were measured on wheat, kale, barley, grass-clover ley, and potatoes grown in rotation. Two rates of N were tested. A strip of permanent grass had the same treatments as the arable crops.3. Winter wheat yielded most dry matter, but wheat yields were increased least, proportionally, by added nutrients. Potatoes gave the smallest yield without manure and responded most to nutrients, yields being increased almost sixfold by NPK fertilizer plus FYM. Kale, barley and grass-clover ley were intermediate in their unmanured yields and in their responses.4. All crops except the grass-clover ley responded to N; kale responded most and wheat least. Potatoes kale and barley responded roughly equally to P and needed this nutrient more than did wheat and the ley. Potatoes responded most to K, yields of wheat and clover ley were also small without K, but barley and kale needed K less. Interactions between nutrients were large with most crops, particularly with N on kale and K on potatoes, wheat and clover.5. FYM greatly increased yields of all crops but responses were less when fertilizers were also given. Potatoes responded most to FYM whether or not fertilizers were also used. FYM also caused large increases in yields of grass-clover ley, kale, and permanent grass.
Viability of axillary buds of white clover (Trifolium repens) in grazed pasture
Authors: Newton P. C. D. , Hay M. J. M. , Thomas V. J. , Dick H. B. 
Published: March 2009

SUMMARYStolon nodes of white clover were sampled monthly for 18 months from continuously grazed (set stocked) and rotationally grazed pastures in New Zealand. Both pastures were stocked at 22·5 ewes plus lambs/ha. Axillary buds were classified into viability categories using an incubation technique. On average, 54% of nodes had non-viable or dormant buds, 25% had axillary buds that were viable but non-active and 0·1% bore reproductive buds. Although 21% of buds emerged, only 8·5% of nodes bore live branches. Bud activity was strongly inhibited during the spring period of both years and this inhibition could not be removed by incubation.The greatest bud viability occurred at node 4 (from the apex) although 30–40% of the buds at this position were non-viable. This pattern of variation changed somewhat with season. Some viable buds were present at nodes more than 20 from the apex but these were of low vigour. Secondary stolons had different patterns of bud activity from those of primary stolons until they comprised more than 16 nodes.
Experiments on the effects of phosphate applied to a Buganda soil: III. A chemical study of the soil phosphate, the fate of fertilizer phosphate and the relationship with iron and aluminium
Authors: Le Mare P. H. 
Published: March 2009

SUMMARYSolubility products (pKsp) for iron and aluminium hydroxides and phosphates have been determined in a Buganda acid clay loam. Significantly greater values, i.e. lower solubility products occurred when determined at a soil:solution ratio of 0·4 than at 0–8. In the most acid soils, pH 4·8–5·0, values of pKsp) were consistent with the possibility that iron and aluminium concentrations were controlled by goethite and gibbsite. Above pH 5 the data indicated that these minerals were not effective. The maximum pKsp) value for iron phosphate was too small to be consistent with that for strengite, indicating that this mineral did not affect phosphate concentration in the soil; the maximum value for aluminium phosphate was consistent with that for variscite but the occurrence of this mineral cannot be deduced from the data. Triple superphosphate applied at 8 cwt per acre or less was converted within 2 years to a very insoluble form, having a solubility similar to that of variscite; with 16 cwt per acre the phosphate concentration was much greater than with the smaller dressings after this period and the soils appeared supersaturated with variscite.
Chemical composition and cold hardiness of the pith in marrow-stem kale
Authors: Thompson K. F. , Taylor J. P. 
Published: March 2009

SUMMARYPercentages of soluble dry matter (S.D.M.), determined in expressed sap from the pith of kale stems by using a hand refractometer, were higher near the vascular bundles than in the centre of the pith and also varied from the top to the base of any one stem. Sampling errors were minimized by taking vertical borings midway between the vascular bundles and the pith centre and by taking two bores per stem (base and top). Inbred lines varied for mean S.D.M. Relative S.D.M. values for two inbred lines were maintained through wet and dry periods in the autumn, and values for fifty-eight inbred lines were significantly correlated in the successive years, one with a dry autumn and the other with a wet.S.D.M. values were positively and significantly correlated with dry-matter percentage (D.M.) of the pith and with total water soluble carbohydrates (W.S.C). Close correlations were also found between S.D.M. and resistance to cold damage, both in the field and in freezing cabinets for inbred lines of marrow-stem kale and for other cultivars of Brassica oleracea. Although there are some exceptions to these correlations, the rapid method for determining S.D.M. should be very useful in screening breeding material for cold resistance. The combination of high percentage digestibility of the dry matter of stems and improved winter-hardiness can be achieved by selecting in addition for low fibre content using penetrometer tests.
The use of biochemical parameters in controlling nutritional state in pregnant ewes, and the effect of undernourishment during pregnancy on lamb birth-weight
Authors: Russel A. J. F. , Doney J. M. , Reid R. L. 
Published: March 2009

1. Fifty-one Scottish Blackface ewes were divided into three groups and individually fed throughout the latter half of pregnancy: (I) in excess of nutrient requirements, (II) to produce a uniformly moderate degree of undernourishment during the last 6 weeks of pregnancy, and (III) to produce a uniformly severe degree of undernourishment during the last 6 weeks of pregnancy,2. The prescribed levels of undernourishment were maintained by weekly adjustments of feed intake based on plasma FFA levels (group II) and plasma ketone levels (group III). The use of the technique is discussed.3. Undernourishment during the latter half of pregnancy reduced birth weights of single and twin lambs after adjustment for weight of the dams to the same extent. In the moderately undernourished ewes the reduction was approximately 10%, and, in the severely undernourished ewes, approximately 25%.
The use of faecal nitrogen as an index for estimating the consumption of herbage by grazing animals
Authors: Arnold G. W. , Dudzinski M. L. 
Published: March 2009

Data from thirty-five digestibility trials with sheep in metabolism cages were used to investigate statistically the relationships between organic matter intake (I), faecal organic matter output (F), and the nitrogen concentration in faecal organic matter (N).The data fell easily into groups due to botanical or seasonal differences in the feed. These groups of data were homogeneous and provided highly significant linear equations of the forms I = bF + cFN and I = a + cFN. When compared these groups of data sometimes showed differences in slope, position or both. A quadratic expressionI = bF + cFN + dFN2was found to accommodate a majority of the data but to be less precise than I = a + cFN.A further expression incorporating N as an independent variable was also examined,I = a + cFN2 + eN.This expression, although far from being universally adequate, proved to be generally better than existing formulae. When applied to the data of Greenhalgh et. al. (1960), it substantially reduced heterogeneity between data for spring and data for summer pastures.Causes of variation in the relationship between organic-matter intake and nitrogen in faeces, and some of the hazards of extrapolation from empirical regression relations, are discussed.
The decline of a pea root eelworm (Heterodera göttingiana Liebscher) population in the absence of host plants
Authors: Moriarty F. 
Published: March 2009

1. The decline of a pea root eelworm (Heterodera göttingiana Liebscher) population, of which most eggs were formed in 1955, was measured annually from 1955 to 1958 in twenty-two microplots containing loamy sand, and measurements were continued in one of these microplots from 1960 to 1962.2. Sampling errors increased when egg populations were more than 4 years old.3. Two crop rotations (fallow, and maize, fallow, carrots) had no effect on decline rate from 1955 to 1958, nor did initial eelworm density.4. After 3 years the egg population was still 48% of that in 1955. Subsequently the population declined on average by more than 50% per annum. It is suggested that host crops should not be grown more than once every five years.5. Cysts declined more slowly, with a mean annual rate of 26%.6. A sharp decline in eggs during the first year followed by at least one year's relative quiescence may be general in Heterodera species; with H. göttingiana unexpected crop failures may be associated in part with the prolongation of this relative quiescence for more than 1 year.
Genetic aspects of appetite and feed choice in animals
Authors: Owen J. B. 
Published: March 2009

Body composition in wild animals is regulated within a band that encompasses variations due to seasonal food supply and physiological state (e.g. that of the reproducing, lactating female and the growing juvenile). This body composition is characteristic of the genotype and is notable for the avoidance of obesity (Pitts & Bullard 1968). Urgent behavioural responses are also invoked to minimize weight loss. Figure 1 illustrates this homeostasis diagrammatically for the non-lactating, mature animal.In this integrated complex, both food intake (quantity) and diet choice (quality) play a major role in achieving the required balance between food-energy intake and ‘net output’ of energy in its various forms such as activity, growth, lactation and change in body reserves. The development of such a system, through evolution, to achieve optimum reproductive fitness in a given environment, is consistent with the theory of optimal foraging which is characteristic of many animals in the wild. Newman (1991) has used such an approach in modelling diet selection by sheep.Domesticated animals have inherited the complex genome of their progenitors, albeit modified in certain respects through natural and artificial selection, in their new circumstances. Many aspects of the physiology and behaviour of the domesticated animal still relate to the environment in which they evolved. For example Jensen & Redbo (1987) have demonstrated the complex nesting behaviour retained by the modern domestic pig, under free ranging conditions similar to those of its wild progenitor.Two major non-genetic factors have emerged as major influences on the appetite of domesticated animals and man in modern times.
Effect of varying seed rates and transplanting clonal tillers on the performance of rice under intermediate deepwater conditions (0–80 cm)
Authors: Sharma A. R. 
Published: March 2009

SUMMARYUnder intermediate deepwater conditions (0–80 cm) at Cuttack, India, direct sowing of the semi-tall rice variety Utkalprabha with 200–800 seeds/m2 produced similar yields in 1989 when heavy rainfall (105 mm) after sowing resulted in more than 50% germination, followed by the gradual accumulation of water in the field. However, in 1990, which was characterized by drought in the initial stages, leading to poor germination (35–40%), followed by a sudden accumulation of water, the crops sown at 200 seeds/m2 produced a significantly lower grain yield than those sown at higher seed rates. Higher seed rates increased plant height, tillers/m2 and panicles/m2 but the associated decrease in panicle weight resulted in similar grain yield production. There was no decrease in the yield of crops sown at all seed rates in 1989 and at > 400 seeds/m2 in 1990 when clonal tillers were removed after 60 days to transplant either the equivalent of or double the uprooted plot area. The loss due to decrease in panicles/m2 with the removal of clonal tillers was compensated for by the resulting increase in panicle weight. The crop planted from clonal tillers produced a significantly higher grain yield than that planted from seedlings of equivalent age raised in a nursery seed-bed with or without fertilizer application. Furthermore, the clonal-propagated crop tolerated simulated flash-flooding better at the early vegetative stage, measured by less tiller mortality and relatively higher dry matter production than in the crop raised from nursery seedlings. Therefore, planting with clonal tillers uprooted from a well-established direct-sown crop is recommended under excess water conditions.
The retention of certain minerals in pigs from birth to 90 kg live weight
Authors: Mudd A. J. , Smith W. C. , Armstrong D. G. 
Published: March 2009

SUMMARYA method of preparation of the whole bodies of pigs, suitable for the analyses of their mineral contents, has been described. Two litters of pigs were slaughtered at birth and another two at 8 weeks of age and each pig was analysed for whole body content, of Ca, P, Mg, Na, K and Cl. From another litter of pigs a gilt and castrated male were slaughtered at 23, 41, 54 and 90 kg live weight and their bodies analysed for the same elements. The data were used to derive a series of regression equations relating mineral contents to empty body weight for pigs at birth, 8 weeks of age and from 23 kg to 90 kg live weight. The regression coefficients, which provide a measure of the amount of a particular mineral retained in g/kg increase in empty body weight were, for pigs at birth Ca, 7·9; P, 6·3; Mg, 0·3; Na, 1·5; K, 1·9; Cl, 4·8; for pigs at eight weeks of age, Ca, 13·3; P, 7·4; Mg, 0·5; Na, 1·6; K, 2·3; Cl, 1·7; and for pigs from 23–90 kg live weight Mg, 0·4; Na, 1·3; K, 2·0; Cl, 1·1. For the older pigs Ca and P retentions (g/kg increase in empty body weight) ranged from 13·5 (Ca) and 7·6 (P) at 23 kg empty body weight to 4·3 (Ca) and 1·0 (P) at 90 kg empty body weight.
The concentration of minerals in the blood of genetically diverse groups of sheep. III. Correlations among calcium, phosphorus, magnesium, potassium, sodium, chlorine, and copper concentration
Authors: Wiener Gerald , Field A. C. 
Published: March 2009

SUMMARYTwo sets of correlations among blood mineral concentrations were calculated (1) those attributable to the effects of various factors (breed, age, lambing performance, etc.) and (2) those remaining (residual) when the effects of such factors had been removed as sources of variation in mineral concentration (the equivalent of correlations within subclasses).Correlations arising from breed differences in mineral concentrations were highest for Ca.P (– 0·81), Ca.Cu (0·83) and P.Cu (–0·95). Correlations consequent on changes with the age of the sheep were most marked for Ca.Mg (0·97, P < 0·01) and Cu.K (–0·92, P < 0·05) and approximately 0·8 (P < 0·1) for Ca.K, P.Mg, P.K and K.C1.Residual correlations were all below 0–2 (although seven of the twenty-one were statistically significant, P < 0·05) suggesting that within subclasses most of the variation in the concentration of anyjone mineral was independent of that in the other minerals. Simple and partial correlations were very similar in magnitude suggesting that the associations found between pairs of minerals were not attributable to joint co-variance with any of the other five minerals.As the sheep grew older, changes in the concentrations of Ca, P and Mg were significantly correlated with the increases in live weight. Within subclasses, differences among the sheep in live weight were significantly (P < 0·05) and positively correlated with differences in the concentrations of Ca (r, 0·11), Mg (0·13) and Cu (0·11).
Levels of first winter feeding in relation to performance of Cheviot hill ewes: VI. Life-time production form the hill
Authors: Gunn R. G. 
Published: March 2009

SUMMARYThe effects of different levels of first-winter nutrition over 3 years were studied on the subsequent life-time production from the hill of groups of North and South Country Cheviot ewe hoggs (sheep between 6 months and 1½12 years).Lamb production was examined in terms of the percentage of lambs born and reared per ewe alive at each lambing and was expressed as a mean of five lamb crops. An overall measure of flock life-time production was calculated from the data on lamb production. This was the total number of lambs weaned at a mean 15 weeks in each treatment group over five lamb crops expressed as the mean per experimental animal alive at 6 months.All productive components were analysed for differences between breeds, treatments, and weight-classes, i.e. those animals above or below average weight at 6 months.There were no significant treatment differences in life-time production, although the treatment groups showed different trends with increasing age. Higher production in early life following higher levels of first-winter nutrition was associated with less efficient later production and poorer ewe survival in a hard hill environment.It is concluded that improvement in first-winter nutrition above that available on the hill is undesirable and uneconomic without equal improvement in adult nutrition.
Lipid composition of lymph and blood plasma of the cow
Authors: Leat W. M. F. , Hall J. G. 
Published: March 2009

SUMMARYSamples of prefemoral, thoracic and intestinal duct lymph have been collected under acute conditions from three cows grazing pasture and the lipid composition compared with that of plasma.The concentration of lipids in peripheral lymph was 16–36% of that found in plasma; the fatty acid compositions of peripheral lymph lipids were similar to those of plasma.Of the fatty acids present in intestinal and thoracic lymph 86 and 76% were esterified as triglycerides, 10 and 13% as phospholipids and 3 and 5% as cholesterol esters, respectively. Saturated and mono-unsaturated fatty acids were preferentially esterified as triglycerides whereas di- and tri-unsaturated acids were associated more with phospholipids. The content of di- and tri-unsaturated fatty acids was greater in the triglycerides and phospholipids derived from the intestine than in those found in plasma.The di- and tri-unsaturated fatty acids in intestinal and thoracic lymph were transported mainly in the form of triglycerides (45–62%) and phospholipids (21–33%). Cholesterol esters were quantitatively of minor importance in the transport of these fatty acids in lymph. The intestine does not appear to play any major role in the formation of the high concentration of cholesterol ‘linolenate’ found in bovine plasma.The process of lipid digestion in the cow appears to be similar to that found in sheep.
The influence of intake of dietary energy in pregnancy and lactation upon sow productivity
Authors: Elsley F. W. H. , MacPherson R. M. , McDonald I. 
Published: March 2009

SUMMARYFifty-two Large White gilts, arranged in thirteen groups of four litter sisters, were allocated at mating to one of four treatment groups. These treatments, arranged as a 2 × 2 factorial, allowed daily energy intakes in pregnancy of 8·3 Meal (H(e)) or 5·2 Meal (L(e)) and of average daily intake during lactation of 20 Meal (h(e)) or 13·8 Meal (m(e)). Daily intakes of protein, minerals and vitamins were similar for all treatments. There were no consistent differences in health or breeding regularity between the treatments.The H(e) sows had a net gain in pregnancy 22 kg greater than the L(e) sows. Feeding the higher level in lactation (h(e) resulted in a reduced sow weight loss during lactation of 20, 12 and 10 kg in the first, second and third parities respectively, as compared with the m(e) sows. There were no consistent effects on the numbers of pigs born apart from the first litter in which L(e) sows produced significantly larger litters at birth. The higher energy intakes in pregnancy and lactation led to very similar increases in the weights of the piglets, of the order of 0.1 kg at birth, 0.4 kg at 3 weeks of age, and 1.1 kg at 8 weeks of age. Sowsgiven the same overall energy intake throughout their reproductive life (H(e) m(e), L(e) h(e)) at the end of the third litter had similar live weights and had produced a similar total weight of weaned pigs. The practical implications of these results are discussed.
The effects of different levels of food intake on fattening pigs in the humid tropics
Authors: Houghton T. R. , Buttbrworth M. H. , King D. , Goodyear R. 
Published: March 2009

1.Two experiments were carried out to investigate the possibility of sustaining good growth rates and high feed conversion efficiency on restricted levels of feed under conditions of high temperature and humidity.2. Large White pigs were used over the weight ranges 50-90 lb. and 90-160 lb. live weight.3. In Exp. 1, three groups each of eight pigs were fed on three planes, high, medium and low, the aim being to restrict energy intake while providing adequate protein intake for good growth. In Exp. 2, two groups each of eight pigs were fed on the medium plane from 50-90 lb. live weight and thereafter one group remained on the medium plane, while the other was fed a very low plane. The very low plane consisted of a daily feed allowance of 31b. 4oz. from 90 to 1601b. live weight. All the pigs were individually fed.
A study of the composition of Clun Forest ewe's milk
Authors: Ashton W. M. , Owen J. B. , Ingleton Jean W. 
Published: March 2009

Little information is available on the composition of the milk of British breeds of sheep under conditions prevailing in this country.1. This paper presents results of the analysis of milk from 46 Clun Forest ewes suckling lambs during 1961 and 1962. Three groups of ewes were used, two of which grazed while a third was fed indoors. Milk samples were obtained by handmilking one quarter while the lamb sucked the
other, after a period of 5 hours during which suckling was prevented by means of udder covers.
Studies on lucerne and lucerne-grass leys V. Plant population studies with lucerne
Authors: Jarvis R. H. 
Published: March 2009

1. An experiment designed to investigate the growth and yield of lucerne over a wide range of plant populations is described and the results discussed.2. The mean yields of lucerne per plant were fitted to three different equations relating yield per plant to plant population, and the ‘goodness-of-fit’ of these equations was compared.3. As plant population increased, the yield of lucerne per acre increased very rapidly up to a certain level, but further increases in plant population led to much smaller increments in yield. It is argued from theoretical considerations that the yield per acre would reach a maximum only when the plant population is infinite.