bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of white clover and fertilizer nitrogen on clover and grass leaf dimensions, percentage cover and numbers of leaves and tillers
Authors: Hollington P. A. , Wilman D. 
Published: March 2009

SummaryEffects of seven levels of N application and three seeds mixtures were studied on two sites for 4 years. One seeds mixture comprised perennial ryegrass (Lolium perenne L.) and two comprised perennial ryegrass with white olover (Trifolium repens L.). One site (Trefloyne) was 24 m above sea level on deep soil and the other (Pwllpeiran) was 328 m above sea level on relatively shallow soil. The plots were cut seven times per year.The application of N to swards without clover considerably increased the number of ryegrass tillers as well as increasing ryegrass leaf blade length and width and sheath length. At Trefloyne the presence of clover greatly reduced the number of ryegrass tillers, had a greater positive effect on grass sheath length, relative to its effect on blade length and width, than that obtained by applying fertilizer N to a sward without clover, and tended to reduce grass leaf length during the winter. At Pwllpeiran the clover was less competitive, but it still tended to have a greater effect on sheath length and a less positive effect on numbers of tillers, relative to its effect on blade length and width, than that obtained by applying fertilizer N to a sward without clover. The application of N to grassolover swards increased the size of grass leaves and the number of tillers, but did not increase clover leaflet size. The number of olover leaves in the sward was greatly reduced by fertilizer N at Pwllpeiran, but was not affected by fertilizer N at Trefloyne. Blanca white clover had larger leaves than Aberystwyth S.100, but S.100 appeared to compensate for this by producing rather more leaves. In respect of number of leaves, leaf dimensions and rate of leaf emergence, clover appeared more sensitive than ryegrass to the differences between the sites. The leaf dimensions of the clover varied more from one time of year to another, but not from one year to another, than those of the ryegrass. The number of leaves per unit area of ground varied more in clover than in grass from year to year and from one time of year to another. The rate of emergence of leaves was faster in clover (per marked stolon tip) than in grass (per tiller).
Fleece development and wool growth on the Romney lamb
Authors: Henderson A. E. 
Published: March 2009

The extent to which early environment affects wool production of Romney sheep was studied by means of measurement of skin growth, and of fibre numbers and dimensions, of lambs reared to 52 weeks on contrasting planes of nutrition.Measurement of skin growth revealed a series of gradients which generally conformed with growth and development principles. A great degree of individuality among animals in skin growth on various regions was expressed, and it was not possible to prove that plane of nutrition caused differential skin growth among regions.An initial low plane of nutrition had a retarding effect on fleece development and fibre growth, but it could not be decided whether there was a permanent effect on fibre numbers. It seems that this is of little practical importance, since a low plane of nutrition during the major part of the follicle development phase does not appear to impair subsequent unit area production, providing immediate nutrition is good.Examination of fibre attributes, and quantitative fibre growth characteristics on various regions of the body, showed a series of orderly gradients. Large differences existed between the body regions for quantitative production per unit area and this suggests a widely differing nutrient supply of various skin regions.The importance of immediate nutrition is emphasized. It appears that permanent effects of early environment on future productivity take the form of a lesser area on which wool is produced. The efficiency of the processes, apparently, is not affected.
The importance of vitamin B12for pig feeding
Authors: Dammers J. 
Published: March 2009

After it had become evident that vitamin B12can be considered as a part of the so-called ‘Animal Protein Factor’, several experiments with young fattening pigs have been carried out in the Netherlands. The purpose of these experiments was to gain experience as to the value of products rich in vitamin B12for pig feeding. In these trials 312 animals were used.The results can be summarized as follows:1. Substitution to a large extent of animal protein by vegetable protein in rations containing tho same total percentage of protein resulted in a retardation of growth.2. Addition of vitamin B12supplements to feed mixtures low in animal protein in this series of experiments generally gave better results than could be obtained without this addition. In the majority of cases, however, the results did not equal those of the groups which received rations containing the usual amount of animal protein.3. Vitamin B12can be considered as a component of the animal protein factor, but besides this there probably exist other factors which contribute to the special value of animal protein for young pigs.4. In circumstances such as prevail in the Netherlands, little benefit can be derived for pig fattening from the use of products rich in vitamin B12.
The effect of decreasing acidity on the solubility of calcium, magnesium and phosphorus in bran and certain pure salt solutions
Authors: Hill R. , Tyler C. 
Published: March 2009

1. The precipitation of calcium, magnesium, phytate phosphorus, and non-phytate (chiefly phosphate) phosphorus has been determined in ‘hydrolysed’ and ‘unhydrolysed’ bran, with varying amounts of added calcium as calcium carbonate.2. It was found that calcium phytate was precipitated before non-phytate (chiefly phosphate), whatever level of calcium carbonate was added.3. Precipitation began and was more complete under more acid conditions when calcium and Ca: P ratio were high.4. Similar experiments have been carried out using salt solutions containing calcium and phytate, calcium and phosphate, and calcium, phytate, and phosphate. The results were similar in most cases to those of corresponding bran mixtures.5. The above results have been considered in relation to the precipitations which are likely to occur in the small intestine, and the possible effects of these precipitations on absorption are discussed.
Some further observations upon pigs reared in cold pens
Authors: Lucas I. A. M. 
Published: March 2009

The experiment reported here involved thirty-two pigs from birth to bacon weight. During the 9 weeks before weaning sixteen pigs were reared on damp cold floors in a cold building and sixteen were reared on dry cold floors in the same building. After weaning all the floors were kept dry.Before weaning four out of the sixteen pigs in each treatment died, but only one, which was in the wet cold floor group, was suspected of having a liver disease which has been described by Naftalin & Howie (1949). A greater incidence of this disease was expected to occur under the cold environmental conditions of the experiment.After weaning one deformed pig was killed and three other pigs were killed at 40 weeks old. The latter three all had the liver disease. There was evidence that the disease had developed after the pigs were weaned and this indicated that it cannot necessarily be prevented by the provision of dry conditions in a cold house. The growth curves of two of the three pigs fitted the hypothesis that the disease is associated with cold environmental conditions, but the growth curve of the third suggested that it might have contracted the disease during the summer when the minimum air temperature was 54° F.The possibility was discussed that the liver disease is caused by a virus or low nutritional status interacting with the effects of cold environmental conditions.The two pre-weaning treatments had no dissimilar effects upon the piglets' weaning weights, blood haemoglobin levels and appetites for solid food, nor did they have any differential effect upon the growth rates and efficiencies of conversion of food to flesh of the pigs which survived to bacon weight. The bacon carcasses from the pigs born and reared to weaning on wet cold floors were shorter and fatter than those from pigs born and reared on dry cold floors. No explanation could be offered for this difference in carcass conformation.The rates of heat loss from a constant temperature water-bath to an uninsulated concrete floor upon which pigs had not lain were halved by the provision of ½ in. depth of chopped straw bedding. They were also halved if the measurements were taken after pigs had recently been lying on the bare floor, and under these circumstances the provision of ½ in. depth of chopped straw bedding cut the heat losses even further.
Extracted herbage leaf protein for poultry feeding III. The digestibility of the residual product resulting from the extraction of herbage leaf protein
Authors: Hughes G. Pearson , Eyles Dudley E. 
Published: March 2009

1. A digestibility trial is described using sheep fed on the product remaining after herbage leaf-protein extraction.2. The material gave an analysis of 25.7% dry matter, 16.2% crude protein, 0.26% phosphorus, 1.26% potassium and 1.13% calcium.3. The animals showed no loss in body weight during the feeding period.4. The material was of low palatability, and the sheep consumed a maximum of 2½ lb. of dry matter per head daily.5. The average digestibility coefficient of the dry matter was 52.1% and that of the crude protein 67.6%.6. Nitrogen balance determinations indicated a sufficiency of protein in the feed.7. The material barely supplied sufficient potassium and was inadequate in its supply of phosphorus and calcium.
The nutrition of maize in sand culture I. The balance of nutrition with particular reference to the level of supply of nitrogen and phosphorus
Authors: Glover J. 
Published: March 2009

As part of the overall programme of research directed towards an understanding of fertilizer needs of crop plants in East Africa a study of the nutrition of maize in sand culture has been made.The purpose of the work was to study growth and yield in relation to changes in the proportion and concentration of the major nutrients, nitrogen, phosphorus and potassium, and if possible to relate the results to the field behaviour of the crop in fertilizer trials conducted by another section of this organization. Simultaneously studies of the uptake of nitrogen and phosphorus were also undertaken. These latter are discussed in the second paper of this series.This first paper deals only with growth, yield and nutrient content in relation to the nitrogen phosphorus balance, though the methods now to be described were common to all experiments.
Report on a further experiment to compare the fattening values, for beef cattle, of silage made from grass cut at different stages of growth, together with the results of some supplementary experiments
Authors: Dodsworth T. L. , Campbell W. H. McK. 
Published: March 2009

1. A feeding trial is described including four groups of cattle fed on grades I, II and III silages and on swedes, straw and oats respectively.2. The live-weight gains made are recorded, together with the rate of dry-matter intake.3. The efficiency of the dry matter of the diets was calculated.4. All three grades of silage produced a significantly greater rate of fattening than swedes plus straw and oats. There was no significant difference between the fattening values of the three grades of silage.5. The dressing percentages found for 100 silagefed and 71 swede-fed cattle are given. The swedefed cattle yielded a greater average dressing percentage.6. It is suggested that the higher dressing percentage found for root-fed cattle as compared with silage-fed cattle can be attributed to the more rapid elimination of dietary water from the body in rootfed cattle.7. An animal behaviour study is described, the time spent by cattle on the four diets, eating, cudding and lying down, being determined.8. Cattle fed on grass silage spent longer on feeding plus cudding than swede-fed cattle.9. An experiment is described designed to determine the effect of the dry-matter percentage of the diet on the dry-matter intake of ruminants.10. The results indicate that when ruminants are subsisting on a diet consisting solely of succulents, the dry-matter intake is depressed when the dry-matter percentage of the diet falls.
The effect of environmental temperature and humidity on the rectal temperature of calves
Authors: Beakley W. R. , Findlay J. D. 
Published: March 2009

1. The rectal temperatures of three 4-month-old Ayrshire bull calves were measured in individual 6 hr. daily exposures to 15, 20, 25, 30, 35 and 40° C. dry-bulb temperature at low humidity (17 mg./l. absolute humidity) and to 30, 35 and 40° C. at high humidity (7 mg./l. saturation deficit). The experiments on each animal lasted 45 consecutive days and consisted of five replications of these nine environmental conditions. Measurements of rectal temperature were made every 5 min.2. The rectal temperatures of the animals rose with increasing environmental temperature and humidity.
The effect of environmental temperature and humidity on the skin temperature of Ayrshire calves
Authors: Beakley W. R. , Findlay J. D. 
Published: March 2009

1. The skin temperatures at each of eight positions on the trunks of three 4-month-old Ayrshire bull calves were measured at 5 min. intervals in individual 6 hr. daily exposures to dry-bulb temperatures of 15, 20, 25, 30, 35 and 40° C. at 17 mg./l. absolute humidity, and 30, 35 and 40° C. at 7 mg./l. saturation deficit in a modified form of Latin square arrangement of environmental temperature. The schedule of experiments on each calf lasted 45 consecutive days and consisted of five replications of each of the nine environmental conditions.2. The skin temperatures of the calves all rose with increasing environmental temperature, humidity and time of exposure.
The nutritive value of herring ‘alkali-reduction’ meal for chicks
Authors: Carpenter K. J. , Duckworth J. 
Published: March 2009

1. Herring ‘alkali-reduction’ meal—a by-product from the alkali process of herring oil extraction—has been tested as a protein supplement for chicks.2. At high levels of feeding it was toxic.3. At low levels of feeding its nutritive value was low compared with other fish meals.4. The method of manufacture of reduction meal destroys vitamin B12and cystine, but supplementation of the material with vitamin B12and cystine did not greatly enhance its feeding value.
Studies on the soluble nitrogen content of dried samples of grass silage
Authors: John A. , Barnett G. , Miller T. B. 
Published: March 2009

1. The relationship between the soluble nitrogen content (soluble nitrogen/total nitrogen) of samples of dried silage and the pH of the corresponding wet samples has been investigated. It has been shown that a relationship exists between the two, and that when Ns/Nd is high the pH is low and vice versa. Moreover, the product Ns/Nd × d.m. is also related to the pH.2. Again it has been shown that the ratio Ns/Nd bears a relationship to the digestibility of the silage as measured by the Wedemeyer Method in the laboratory. The potential usefulness of the ratio in this connexion is being further investigated.
Field nitrates in Gezira soil
Authors: Jewitt T. N. 
Published: March 2009

The results of two sets of soil nitrate measurements on the three-course rotation plots at the Gezira Research Farm are described. The first set is a long-continued series taken over 21 years; it shows for the first foot samples that there is a distinct tendency for nitrates to be depressed during the rainy season, this tendency being more marked in the more open rotations. This is ascribed to washing down of nitrates. The second set of measurements shows accumulations in the second foot and a distribution consistent with downward movement.In the Sudan Gezira the yields of irrigated cotton are positively correlated with the amount of rainfall in the 6 weeks before sowing. It follows from the work described here that this is not due to increased nitrate in the top foot of soil at sowing time.The sampling of this experiment for nitrate was started by my predecessor, H. Greene, and continued by O. W. Snow. The field experiment itself has been conducted by the Plant Physiology Section of the Research Division of the Ministry of Agriculture.
The effect of undernutrition before calving on the quantity and composition of milk produced by two-year-old heifers
Authors: Flux D. S. 
Published: March 2009

Six pairs of 2-year-old monozygous twin heifers were used to determine the effect of underfeeding for 10 weeks prior to calving. Those which had been well fed before calving produced more milk than their sisters which had been poorly fed.There was no effect on milk or butterfat composition, probably because none of the animals lost much weight after calving.The effect of the treatment differed markedly between twin pairs, the maximum difference in milk yield being 2866 lb., the minimum 135 lb., and the mean 1057 lb. for 270 days' lactation.The ratios of between-twin-pair to within-twin-pair variance for butterfat, total protein and lactose percentages of the milk were as follows:
Some effects of dietary crude fibre on live-weight gains and carcass conformation of pigs
Authors: Coey W. E. , Robinson K. L. 
Published: March 2009

1. The results of six trials have been examined in which pigs received rations with contrasting levels of crude fibre. The contents of crude fibre ranged from 3½ to 11½% and were related to a variety of basal diets.2. The main object of the trials was to study the effect of increased levels of dietary crude fibre on carcass conformation, under conditions where there was no disparity in rate of live -weight gain between the pigs receiving the higher and the lower level of fibre. Thus pigs on the high-fibre diets received extra food in order to equalize the intake of digestible nutrients.3. The results indicate that a rise in the level of dietary crude fibre was accompanied by a fall in the killing-out percentage, and hence by lower carcass weights. This effect was produced even by comparatively small changes, such as a rise from 3½% crude fibre to about 5% crude fibre. The results also show that carcass weight was positively correlated with back-fat thickness to a marked degree.4. It is evident that raising the level of crude fibre in the food caused a change in the distribution of live-weight gains, so that when at the same slaughter weights, the high-fibre pigs had lighter carcasses and heavier offal than their low-fibre counterparts. Consequently the high-fibre pigs also had thinner back-fats, and they would tend to grade better under carcass grading systems based on backfat measurements and biased towards thin back-fats.5. It is suggested that these effects are likely to be produced even in pigs considerably advanced in fattening, and that in younger pigs the drawback of retardation in rate of live-weight gain may also be encountered. Thus the use of high-fibre diets in self-feeding systems, as a corrective against over-fatness, may not normally be the best means of attaining this objective under commercial conditions.
Studies of grazing behaviour in relation to grassland management: III. Rotational compared with continuous grazing
Authors: Hancock John , McMeekan C. P. 
Published: March 2009

1. A series of observations on the grazing behaviour of identical twin cattle on two contrasting systems of pasture management—rotationally and continuously grazed—is described.2. The rotationally grazed cows averaged only 11 min. (day/cow) shorter feeding time and 18 min. shorter ruminating time than their continuously grazed co-twins. The total time they spent in work was thus 29 min. shorter.3. While the average differences in total work over the whole trial was not great, the continuously grazed cows worked for appreciably longer daily periods at the time of seasonal feed shortage during which time the rotationally grazed cows were buffered by their pasture diet being supplemented with silage.4. The differences in grazing behaviour between the cows of the two treatments, together with the magnitude of the seasonal variations which occurred in both groups, indicated that dairy cows attempt to maintain a stable production in the face of adverse pasture conditions by increasing their feeding time.5. Previous conclusions based on observations of uniformly treated twins regarding the importance of heredity in the determination of grazing behaviour were fully confirmed.
Small plots and automatic rain shelters: a field appraisal
Authors: Legg B. J. , Day W. , Brown N. J. , Smith G. J. 
Published: March 2009

SUMMARYTwo rain shelters, each covering an area of 210 m2, have been built at Rothamsted for use in tillage experiments and drought experiments. Each shelter automatically moves over the experimental area when rain starts, and moves away when rain stops; thus all rain is kept off, but other aspects of the microclimate are little affected. Small experimental plots were used, and, except in the 0·5 m strips at the plot edges, the height and yield of a barley crop were uniform. Irrigation water to some plots was labelled with tritium; when applied to very dry plots, a measurable proportion of this water moved laterally by more than 1·0 m. However, the total quantity of water transferring between adjacent plots was not large enough to inconvenience the tillage or drought experiments.
The feeding and mating behaviour of pollen beetles (Meligethes aeneus Fab.) and seed weevils (Ceutorhynchus assimilis Payk.) on oil-seed rape (Brassica napus L.)
Authors: Williams Ingrid H. , Free J. B. 
Published: March 2009

SUMMARYDuring the early period of infestation of winter rape, pollen beetles and seed weevils were mainly feeding and attaining sexual maturity. Before a crop flowered pollen beetles fed on buds but only some of those which they had perforated to obtain pollen dropped off. When flowering started adults obtained pollen from flowers rather than from buds. They laid their eggs in the buds but not in the flowers. Larvae moved from flower to flower up the raceme and caused no damage. Probably many podless stalks have been wrongly attributed to pollen beetle damage.Overwintered seed weevils caused no damage by feeding on rape pods. New generation seed weevils caused some loss of seed weight and viability when feeding on pods of spring rape; this is probably unimportant on a field scale.Pollen beetles and seed weevils mated from mid-May until the emergence of new generation adults; these did not mate before hibernating.