bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of artificial fibre bag technique for determining the dig estibility of feeds in the rumen
Authors: Mehrez A. Z. , Ørskov E. R. 
Published: March 2009

SUMMARYThe artificial fibre bag technique was evaluated for assessing the proportions of dietary D. M. and N which disappear in the rumen. The most important factor determining the variability in disappearance from bags incubated together was the sample size in relation to bag size. For incubation of 5 g air dry feed, a bag size of 17 ✗ 9 cm was found to be adequate. There were also variations in substrate disappearance between animals and between days of incubation. It was estimated that three sheep and the measurement of substrate disappearance twice were necessary in order to obtain acceptable repeatability.The technique was found to be satisfactory as a simple and rapid guide for measuring nutrients disappearance in the rumen such as protein degradation and carbohydrate fermentation. It has been used in subsequent work to measure the effect of features of the rumen environment, such as pH and NH3 concentration, on rate of fermentation.
Summer legume intercrop effects on yield and nitrogen economy of wheat in the succeeding season
Authors: Singh S. P. 
Published: March 2009

SUMMARYThe results of experiments conducted for 2 years in north-western India under irrigated conditions are described here. Wheat following legume intercrops gave increases in growth, yield attributes, yield and N uptake. Various legume intercrops such as groundnut, cow peas (both for fodder and grain) and greengram reduced the need of fertilizer nitrogen for wheat in the succeeding season by 30–84 kg/ha compared with sorghum.
A comparison of tissue weight distribution in Landrace, Hampshire and Duroc Jersey pigs
Authors: Goenaga P. R. , Carden A. E. 
Published: March 2009

SUMMARYThe carcasses of 20 Landrace, 20 Hampshire and 20 Duroc Jersey barrows were dissected in order to study the influence of the breed on tissue weight distribution.After weaning, at 56 days of age, the animals were allocated to individual pens and fed a standard diet containing 18% crude protein and 13 MJ ME/kg, until they reached their designated slaughter weight.The Landrace and Hampshire pigs were slaughtered between 60 and 115 kg and the Duroc Jersey ones between 40 and 115 kg live weight. The right half carcasses were completely dissected using strictly anatomical criteria. Individual muscles were classified into eight anatomical groups (Carden & Goenaga, 1977).The results were examined by covariance analyses utilizing the allometric equation. Carcass tissue composition was studied using the weight of the dissected side as covariate. When muscle: bone ratio was examined, the weight of total side muscle was used as the independent variable. The growth of different parts of a tissue relative to the corresponding whole tissue was studied.Concerning carcass composition, there were significant breed differences in muscle and fat contents and in the muscle:bone ratio.Breed differences were found in muscle distribution. The 6 values of muscle groups 1 (proximal hind limb), 2 (distal hind limb), 6 (distal forelimb) and 7 (muscles connecting forelimb to thorax) were statistically different as were the adjusted means of groups 3 (spinal column), 5 (proximal forelimb) and 8 (muscles connecting forelimb to neck and intrinsic muscles of neck and thorax).Significant differences were also found in bone weight distribution. Slope values of the tarsals, os coxae, scapula and sternum were statistically different. Adjusted means of tibia-fibula, sacrum, spinal column, radius-ulna, carpals and ribs were also significantly different.Finally, there were breed effects in the distribution of fat, the relative weight of subcutaneous and of intermuscular fat being statistically different.
The effects of genotype, sex and feeding regimen on pig carcass development: 1. Primary components, tissues and joints
Authors: Evans D. G. , Kempster A. J. 
Published: March 2009

SUMMARYDissection data for 1006 pig carcasses taken from the first 2 years of the Meat and Livestock Commission's (MLC) Commercial Pig Evaluation (CPE) were used to examine the relationships between carcass components and carcass weight over the growth period from 46 to 92 kg carcass weight. Alternative models were tested and parameters examined for different genotypes (pigs from different companies in CPE), sexes (barrows and gilts), feeding regimens (ad libitumand restricted feeding) and years.Generally, linear allometry provided an acceptable description of carcass development, although some curvilinearity was indicated for the head, kidneys, rump back joint, M. psoas and total dissected lean. Growth coefficients conformed to the generally accepted pattern of carcass development in pigs. Using linear allometry, proportional weight increases were comparable for all genotypes and sexes, but dissected fat increased relatively faster on the restricted feeding regimen.At a constant carcass weight of 66·5 kg, all tissue weights and the weights of primary components and most joints differed by genotype. The ratio of carcass lean weights for the two extreme genotypes was 1·04; comparable ratios for carcass fat weights were 1·13 (restricted-fed pigs) and 1·07 (ad libitum-fed pigs).Significant differences were recorded between sexes and between feeding regimens, largely reflecting differences in fatness. Some important year differences were also found.
Relationships between the number of stems produced by a potato seed tuber and its weight
Authors: Wurr D. C. E. , Morris G. E. L. 
Published: March 2009

SUMMARYThe relationships between the number of stems per tuber and tuber characters measured before planting were studied using a wide range of tuber weights of the varieties Désirée and Maris Piper. The effects of the storage temperature of the seed tubers and the site of growth on these relationships were then investigated over 3 years.Linear relationships between the numbers of stems per tuber and tuber weight accounted for more of the variation in numbers of stems than linear relationships established using tuber shape or sprout measurements. The linear relationships had positive slopes and intercepts, showing that small seed tubers produce more stems per unit weight than large seed tubers. There was little evidence of non-linear effects.On average over all treatments, using ten plant samples, single linear relationships between above-ground stems and tuber weight accounted for 64 % of the variation in above-ground stems with D6sire'e and 58 % with Maris Piper. When separate regression lines were fitted for each treatment the best models in each variety accounted for about 86 % of the variation in above-ground stems. The best model with Désirée had parallel lines showing that the advantage, in terms of stem production, of small seed over large seed increases in environments favouring stem development. The relationships for each treatment are used to show how the stem density established can vary when planting tubers at the recommended spacing.Seed tubers of comparable weight, planted at different sites, gave different numbers of stems suggesting that the optimum spacing may vary from one site to another.It is suggested that breeding varieties for yield stability might be aided by selectingfor low variation in the relationship between the number of stems per tuber and tuber weight.
Nutrient relations of winter wheat: 2. Movement of nutrients to the root and their uptake
Authors: Gregory P. J. , Crawford D. V. , McGowan M. 
Published: March 2009

SUMMARYThe purpose of this work was to determine the relative importance of mass flow and diffusion in supplying nutrients to wheat plants and to calculate nutrient uptake rates by roots (inflow). Winter wheat was grown in the field and measurements of plant Na, K, Ca, Mg, P, S and N contents, root length, plant water uptake and soil solution concentration made at regular intervals during growth. The apparent contribution of mass flow to plant uptake of nutrients between mid- April and mid-June was greater than the measured plant uptake for sodium, calcium, magnesium and sulphur (14, 9, 2 and 4 times respectively); however, only 50 % of the measured plant uptake of nitrogen and potassium and 5% of the phosphorus was supplied in this way. There were some 7 day periods when mass flow was able to supply the measured uptake of nitrogen and potassium, and it is possible that for these nutrients the importance of mass flow and diffusion may change during growth. Mean inflows (uptake in mol/cm root/sec) were calculated from sowing until mid- June. Inflow decreased for all nutrients from high initial values to low values during the winter and rose again in mid-April and May before falling in June. The increase in inflow in mid-April was concomitant with increased shoot growth but the precise factors controlling plant demand for nutrients and uptake in the field are still ill-defined.
Agronomic assessment of snap beans (Phaseolus vulgaris) in a warm-temperate semi-arid environment
Authors: Moss Q. I. , Muirhead W. A. 
Published: March 2009

SUMMARYThe production of green beans was studied in sowings made from December to February, September to February, and from October to February in three seasons, and over six oonsecutive seasons for a mid-season sowing.With September-October sowing the rate of emergence was slow, and establishment sometimes poor. Possible virus disease, and the lack of continuity of setting pods resulting from cool weather, were problems. Good yields were obtained from midseason sowings (31 October-18 December), up to 19·6 t/ha, with good yields for late sowings up to 13·9 t/ha in ^he first three seasons. In another three seasons mid-season sowings (late November-early December) resulted in poor yield due to periods of hot weather (> 35 °C max.) prior to and during flowering.There was a relationship between quality and yield. The greatest yield and best quality green pods were obtained when conditions favoured rapid growth and rapid setting of pods, and when there was a high rate of pod maturation.For yield of dry seed the early sowings were best, 3·6 and 2·8 t/ha in two seasons. A total of 460 mm of water was required for the first six sowings, but fell to 360 mm for the mid-February sowing (rainfall plus irrigation).Although it was possible to grow beans over a 9-month period the January and early February sowings appeared to be the least risk prone with the present cultivars.
Establishment and growth of sugar beet as affected by seed treatment and fluid drilling
Authors: Longden P. C. , Johnson M. G. , Darby R. J. , Salter P. J. 
Published: March 2009

SUMMARYSeed treatments and methods of sowing sugar beet were tested in the laboratory and in field trials in 1975, 1976 and 1977 on a range of soil types including a sand, several loams and a peat.‘Advancing’ the seed by controlled imbibition of water followed by drying before sowing, gave 2–3 % more emergence. Seedlings appeared 3–4 days earlier and were up to 50 % heavier at the four to six leaf stage, but by final harvest yields of sugar per unit area were similar from advanced and untreated seed. ‘Priming’ in osmotic solutions of salts or polyethylene glycol, to bring all seeds to the point of germination, before drying back and sowing gave inconsistent effects in the field with emergence percentage frequently being below that of the control. Steeping seed in water, aimed at removing germination inhibitors, improved germination and reduced the time to, and duration of, germination when tested in the laboratory but gave poorer results than the untreated control in the field. ‘Chitting’ the seed in the laboratory greatly improved emergence characteristics but treatment effects in the field were very variable. Chitted seeds were sown in carrier gels in the field to try to protect the radicles from damage but seedling establishment was no better from fluid drilling than from normal dry seed sown ‘raw’ or pelleted in clay, even when only chitted seeds were put into the fluid. Possible reasons for this are discussed.Fluid-drilled seeds consistently gave quicker emergence and larger seedlings. Even when these were 30–50 % heavier, differences had usually become negligible by the end of the average 230 days long growing season, so that sugar yields were not consistently affected by the treatments tested.
Comparison of the action of rumen bacteria on cell walls fromEragrostis tef
Authors: Jane Morris E. , Van Gylswyk N. O. 
Published: March 2009

SUMMARYA selection of the hemicellulose-utilizing rumen bacteria isolated by Henning (1979) were partially characterized. These and a number of other cellulolytic organisms were incubatedin vitrowith teff (Eragrostis tef) cell walls, and the extent of solubilization and utilization by the bacteria of individual cell wall sugars was determined. Results were compared with the action of the bacteria on isolated xylan and cellulose.The cellulolytic rumen bacteria solubilized more of both cellulosic and hemicellulosic sugars in the cell wall than the non-cellulolytic organisms. Bacteria which were unable to solubilize isolated cellulose could also degrade very little of the cell wall cellulose, and this appeared to limit the amount of cell wall hemicellulose which could be attacked.There was no direct relationship between the extent of degradation of isolated xylan and solubilization of cell wall hemicellulose, but those xylanolytic organisms which produced freely diffusible enzymes (as evidenced by production of clearings in 3 % xylan-agar) were more effective in attacking the cell wall than those which did not.Examination of thin sections in the electron microscope showed no relationship between attachment of bacteria to the cell walls and ability to degrade them.
Fat cell synthesis in pigs assessed after administration of tritiated thymidine in vivo
Authors: Kirtland Janet , Gurr M. I. 
Published: March 2009

SUMMARYThe aims of this work were to determine the feasibility of using the incorporation of radio-labelled thymidine into fat cell DNAin vivoas an index of cell division in the adipose tissue of young pigs, and to distinguish between the processes of new cell synthesis and the ‘filling’ of existing ‘empty’ cells.Five Large White pigs were given tritiated thymidine as follows: two animals were injected at 2 days of age, two at 9 days of age and one at 40 days of age. The animals were killed at different times after the injection and adipose tissue was removed from various sites. The tissue was separated, using collagenase, into ‘fat cell’ and ‘stromal cell’ fractions. The specific (radio)activity of DNA isolated from each fraction was measured.Fat cell synthesis occurred rapidly in pigs aged between 2 and 40 days of age. It appeared that by 40 days of age the rate of synthesis declined in backfat such that the filling of pre-existing empty fat cells became a more important contributor to the increased mass of adipose tissue than the filling of newly synthesized cells.
Using Suffolk sheep for improving lamb production from subtropical Egyptian sheep
Authors: Aboul A. M. , el-Shobokshy A. S. , Gabr M. G. 
Published: March 2009

SUMMARYThe performance of Suffolk cross-bred ewe lambs produced either by Suffolk crossbred ewes, 70–90% Suffolk (HS), or by Ossimi ewes, 35–45% Suffolk (LS), was investigated. Forty-three ewe lambs from both groups were available, and were given two different levels of feeding.The LS ewe lambs showed, insignificantly, better growth performance than the HS group, and breed group differences increased with age. They also reached puberty earlier (305·4v.334·6 days for the HS ewe lambs). Using the HS breeding rams rather than the imported Suffolk ones, for improving lamb production from the local sheep flocks, is recommended.The LS ewe lambs started their first breeding season 18 days earlier, and ended 34 days later, than the HS ewe lambs. Both cross-bred groups showed clear anoestrous periods of 225·4 and 202·2 days, respectively. The onset of their second breeding season was similar, on average 29 August. These figures are close to those of the purebred Suffolk ewes, and far away from the nonseasonal local parents.
Growth pattern and its effect on feed utilization of sheep
Authors: Murray D. M. , Slezacek Olga 
Published: March 2009

SUMMARYThe effect of three different growth patterns from 15 to 40 kg live weight on the feed utilization of lambs was studied. The treatments were: high (H) ad-libitum feed intake, low (L) restricted feed intake and high-maintenance-high (HMH) ad-libitum feed intake from 15 to 25 kg followed by a 50-day period during which live weight was maintained constant, which in turn was followed by ad-libitum feeding. Animals were individually penned and fed a pelleted lucerne chaff-cereal grain mixture. Intakes of pellets were converted to digestible organic matter (DOM) using the results of in-vitro digestion studies. Two animals were killed at the start of the experiment (15 kg) and the remaining 27 animals (nine in each treatment) were killed at common live weights of 25, 30, 35 and 40 kg.A marked reduction was observed during weight stasis at 25 kg in the amount of DOM required daily by the HMH animals to maintain live weight. Despite marked compensatory growth by the HMH animals which were rehabilitated after the period of weight stasis, DOM intakes were similar in both these HMH animals and a corresponding number of H animals over identical live-weight ranges.Differences between treatments were found in DOM intake per unit live-weight gain (H < HMH < L), empty body-weight gain (H = HMH < L) and carcass weight gain (H < HMH = L) from 15 kg until slaughter. DOM intake was utilized more efficiently for gains of all these components by HMH animals during compensatory growth compared with H animals over the same live-weight ranges.DOM intakes were related to energy gains in the carcass both for all animals in each treatment from 15 kg until slaughter, and for the H and HMH animals which were killed at 30, 35 and 40 kg from 25 kg. Comparisons of these data showed treatment differences in the efficiency of DOM conversion to carcass energy (H > HMH > L) and that DOM was utilized no more efficiently by HMH animals during compensatory growth than by H animals over identical live-weight ranges.It is concluded that the increased efficiency of utilization of DOM for carcass gain during compensatory growth was due to changes in carcass composition during the period of weight stasis.
The effect of row orientation, date and latitude on light absorption by row crops
Authors: Mutsaers H. J. W. 
Published: March 2009

SUMMARYA model study of light absorption by rectangular hedgerows with different row orientations was made.The effect of row orientation on daily light absorption is greatest around 25° latitude. North–south orientation gives highest absorption for most of the year near the equator. At higher latitudes, up to 55°, absorption is highest with N–S orientation during the summer months and with E–W orientations for the rest of the year, but the magnitude of the difference between orientations decreases with increasing latitude. From 65° upwards, E–W orientation gives highest absorption all the year round, but the difference among orientations is minor. The effect of orientation will be smaller as cloudiness is greater.The results of this study are wholly consistent with yield differences due to different orientations, reported in the literature.
The interaction between environment and level of feeding for pigs from weaning to bacon weight
Authors: Lucas I. A. M. , Calder A. F. C. 
Published: March 2009

1. The rates of growth and efficiencies of food conversion between 45 and 100 lb. live weight of pigs kept to a low plane of feeding were most adversely affected during the winter months by bad housing conditions, wherein the average air temperature was 43° F. On the other hand, this bad housing had no adverse effect upon pigs of a similar size kept to a high plane of feeding.2. The summer season, with consequently higher environmental temperatures in both good and bad piggeries, only had a significantly beneficial effect upon the rates and efficiencies of growth of pigs of 45–100 lb. live weight kept to a low plane of feeding in a bad piggery. Any effects upon the growth of pigs of similar size kept to a high plane of feeding in either a good or bad piggery or to a low plane of feeding in a good piggery did not approach statistical significance.3. There was probably some environmental factor other than air temperature or relative humidity which had a beneficial effect on the growth of the pigs kept to a low plane of feeding in the good piggery.4. It was observed, but not proved, that pigs of 100–200 lb. live weight kept to a high plane of feeding grew rather more efficiently in the bad house than in the good house, despite the higher environmental temperatures in the good house.5. During the growth period between 45 and 100 lb. live weight the efficiency of food conversion, expressed in pounds t.d.n. required per pound liveweight increase, was better in the well-housed pigs kept to the low plane of feeding than in the highplane pigs housed in either piggery.6. During the growth period between 100 and 200 lb. live weight the efficiency of food conversion of the well-housed low-plane pigs was significantly better than that for the well-housed high-plane pigs, but was not significantly better than the efficiency of food conversion of the high-plane pigs from the bad piggery.
Slaughter losses and yield of Wiltshire bacon
Authors: King J. W. B. 
Published: March 2009

A study has been made of variations in the shrinkage from the live pig to the carcass and from the carcass to the side of Wiltshire bacon. Most of the variation occurs at the first stage when the losses have a variance of 17·67 lb. compared with only 4·59 lb. and the second stage. Similarly, breed differences were found at the first stage, Wessex and Essex pigs giving 1·1 and 2·7 lb. more carcass respectively than the Large White pigs, but not at the second stage. On the other hand, differences between litter groups were found at both stages.Correlations made between carcass measurements and yield of carcass and bacon were generally found to be small and positive. Antagonisms were indicated between quantity and quality of bacon, in particular by positive correlations between thickness of back-fat and weight of carcass, and between a desirable proportion of cuts and losses on slaughter. The problem of deciding the relative attention which should be paid to various carcass characteristics is discussed and the need for an index of total carcass merit is pointed out.