bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nutrition in relation to reproduction in sows
Authors: Hafez E. S. E. 
Published: March 2009

Gilts of the ‘Palouse’ breed were divided into two groups; one group was full fed from weaning to 1501b. and the other group was fed 70% of full feeding. After six generations, one-half of the pigs in each group were shifted to the other plane of nutrition, thus forming four groups: high-high (HH), low-high (LH), low-low (LL) and high-low (HL). F10 gilts were slaughtered 38 or 100 days post-coitum to study reproductive and prenatal phenomena.1. Ten successive generations of controlled feeding had no significant effect on: length of Fallopian tubes, weight of corpus luteum, percentage of implantation, number of viable foetuses, foetus weight, weight of placental membranes, volume of placental fluids or embryonic mortality.2. There were significant differences between the high and low planes of nutrition in: weight of pituitary, thyroid and adrenals, weaning weight, puberty weight, puberty weight to birth weight, puberty weight to weaning weight and puberty age. The effect of six generations of controlled feeding was not maintained when the plane of nutrition was changed from high to low or low to high.3. The frequency of silent heat and the number of services per conception was lower in the low planes than in the high planes.4. Ova migration occurred in both directions in 41% of the gilts; one to four ova migrated. The foetal sex ratio ranged from 4:0 to 1:7 with an average of 1:1. The sexes were unevenly distributed in the horns.5. Foetus weight at 38 or 100 days post-coitum was not affected by plane of nutrition or sequence in the uterine horn.6. Within-litter variations were highest in the volume of allantoic fluid followed in order by variations in weight of placental membranes and then the amniotic fluid and foetus.7. Foetal mortality was not related to sequence in the uterine horn or the number of implantations.8. There seemed to be two peaks of early prenatal mortality, one at implantation and another at the onset of organo-genesis.
Establishment Studies. I. The effect on spring oats of undersowing with a one-year ley
Authors: Charles Allen H. 
Published: March 2009

A field experiment was carried out to study the effect on spring oats of undersowing with broad red clover, Italian rye-grass and a mixture of both. Two levels of nitrogen were used, namely, no nitrogen and 3 cwt. per acre of ‘Nitro-Chalk’.1. Oat shoot weight was reduced by undersowing, Italian rye-grass having a greater effect than red clover, particularly where nitrogen was applied.2. In the absence of nitrogenous fertilizer undersowing did not reduce oat plant height, but where nitrogen had been given, Italian rye-grass either alone or in a mixture with the clover, reduced the height; the legume alone had no effect.3. Undersowing generally reduced the number of oat panicles. Italian rye-grass had no effect when nitrogen was not applied, but a marked reduction was observed when nitrogen was applied. The legume had the greater influence where nitrogen was not applied.4. Red clover increased the number of whorls, and the number of single-grained spikelets per panicle. Grass sown alone or with clover reduced the number of single-grained spikelets per head.5. The total number of grains per panicle, 1000 grain weight, percentage husk and the percentage of saleable grain were not influenced by undersowing.6. No lodging occurred but there was an indication that resistance to bending of the straw was affected by undersowing with Italian rye-grass.7. Seeding herbage under the oats had a bigger influence on the yield of straw than grain. Italian rye-grass sown alone or with clover reduced the yield of straw where nitrogen had been applied. The legume alone had no effect. Grain yields showed a similar trend.8. Yield and percentage crude protein in the straw were reduced by Italian rye-grass alone or in a mixture with clover when nitrogen was applied, but there was no effect where nitrogen was withheld. The grass had a greater effect than red clover while a mixture of both was intermediate to the legume and grass sown separately. Italian rye-grass greatly reduced the recovery of applied nitrogen by the cereal.9. The percentage moisture in the oat sheaves was increased by undersown herbage and red clover had a bigger influence than the grass. The application of nitrogen reduced the bulk of clover under the cereal and its adverse influence on the harvesting of the oats. In the absence of undersowing, nitrogen had no effect on the percentage moisture in the sheaves.
Studies of the skeleton of the sheep. IV. The effects and interactions of dietary supplements of calcium, phosphorus, cod-liver oil and energy, as starch, on the skeleton of growing blackface wethers
Authors: Benzie D. , Boyne A. W. , Dalgarno A. C. , Duckworth J. , Hill R. , Walker D. M. 
Published: March 2009

1. A factorial experiment on wether hoggs was carried out to examine the effects on bone growth and composition and on blood composition of four dietary factors. The factors were extra calcium, phosphorus, vitamin D, and energy in the form of starch, and each was fed in all possible combinations, so that there were sixteen dietary treatment groups in all. Each group consisted of three animals.2. Serum calcium and blood inorganic phosphorus concentrations were determined monthly, and radiographs of most parts of the skeleton were taken at the beginning and end of the experiment. After about 6 months on the experimental diets the animals were killed and the ash weights and percentage of ash of different parts of the skeleton and of the whole skeleton were determined. Live-weight changes and food intakes were also measured.
The grazing preferences of cattle and sheep
Authors: Cowlishaw S. J. , Alder F. E. 
Published: March 2009

Factors affecting the grazing habits of ruminants are discussed in relation to the attractiveness and nutritive value of herbages and the observed preferences of cattle and sheep at different times.Methods of measuring stock preferences are considered and it is concluded that, while frequent eye estimates of the quantity of each species appear to provide an adequate method, continuous observations and herbage sampling are useful adjuncts to it.The results of five experiments are given. Four were carried out in 3 years' winter grazing and one on spring, summer and autumn grazing over 2 years. In the latter experiment herbage samples were chemically analysed and a relationship with the observed preferences was calculated.In the winter grazing trials the greener grasses tended to be selected first, i.e. timothy, white clover, rough-stalked meadow grass, perennial and Italian rye-grass. Cocksfoot, Phalaris, red fescue and meadow fescue were not generally relished. Meadow foxtail, smooth-stalked meadow grass, tall fescue and sometimes the different varieties of rye-grass and timothy varied in rank from year to year as a result of differential frost damage and fungal attacks.In the summer grazing trials lucerne and white clover were found palatable in all the 1956 trials; in 1957 lucerne remained so, but white clover was less well liked, especially in June and July. The amount of grass growing with the clover seemed to affect attractiveness, mixtures being preferred to either species by itself. Meadow fescue and timothy were always ranked high, perennial rye-grass and cocksfoot usually next. Agrostis and red fescue were lowest. For the grasses, preference rank was positively correlated in 1957 with water-soluble dry matter, water-soluble ash, water-soluble carbohydrate and negatively correlated with lignin content.Results are compared with those of other investigators and they show a marked degree of similarity. Variability in the data for sheep is possibly due to limitations in technique. The results for sheep and for cattle are compared; and it was generally found that cattle were fonder of meadow fescue than sheep, and less fond of cocksfoot.Stock appear to graze those plants which will most readily supply their requirements for salts and energy (carbohydrates). Factors like dung, fungal attack, accessibility, density and toughness may interfere with this relationship.
The morphology of bovine sweat glands and the effect of heat on the sweat glands of the Ayrshire calf
Authors: Findlay J. D. , Jenkinson D. McEwan 
Published: March 2009

1. The normal sweat glands of twenty-eight calves, nineteen live adult cattle and eighteen slaughtered cattle from temperate breeds were examined. In every animal the lumen of the sweat glands contained a fluid-like material.2. It appeared on examination and rough measurement that the size of the sweat glands taken from animals after slaughter was smaller than that of the glands taken from live animals even when the same sampling technique was used for both.3. The sweat glands of sixteen calves were examined before and at intervals after the animals had been subjected to a hot environment. The glands were always seen full of a fluid-like material.4. It is concluded that if the calf sweat gland is stimulated by heat stress it must function either (a) by simple diffusion through the sweat gland wall and hence to the skin surface, or (b) by a secretory process not involving degeneration of the glandular epithelium. It is probable that at least part of the contents of the lumen of the sweat glands is derived from the epithelium by a process of active secretion.
Observations on the grazing behaviour of lactating dairy cattle in a sub-tropical environment
Authors: Holder J. M. 
Published: March 2009

1. Three trials are reported in which the grazing behaviour of separate groups of cows, one receiving supplementary food, either as conserved roughage, concentrate or fodder crop, was observed over 24 hr. periods. A fourth trial, assessing the effect of summer temperatures on unshaded milking cows, is briefly described.2. In trials 1 and 2 the stall feeding of either conserved roughage or concentrate reduced grazing as compared with unsupplemented cows by approximately 10%.3. Allowing access to a fresh ‘strip’ of a fodder crop at a set time each day, whilst not altering total grazing time, very markedly altered periodicity of grazing. Cows delayed grazing up to 3 hr. whilst awaiting a fresh ‘strip’.4. Environmental temperatures up to 87° F. did not alter total grazing time as compared with grazing time when temperature reached a maximum of only 70° F.5. The value of supplementary feeding of dairy cattle at pasture, at least where the intake of pasture is sufficient for maintenance and a low level of production, appears to be open to question.
The uptake of radioactive strontium by crops under field conditions in the United Kingdom
Authors: Milbourn G. M. 
Published: March 2009

1. Field experiments are described in which the absorption of radioactive strontium by rye-grass and lucerne has been investigated during 1958 on five soil types which represent a range in exchangeable soil calcium content. 89Sr was applied as a spray to both arable land and to established pasture.2. Absorption was reduced by a factor of up to 4 in rye-grass (shallow rooted) following ploughing to 11 in. compared with leaving the contamination on the soil surface. These results are compared with those obtained in an earlier series of experiments in 1957.3. The ratio of 89Sr to calcium was highest in crops grown on soil low in calcium (2 m-equiv. Ca per 100 g. extracted with N-ammonium acetate).4. The addition of lime reduced absorption of 89Sr from the soil only when the exchangeable soil calcium content was relatively low. Some effect was observed in soils containing 7–8 m-equiv. Ca/100 g., a considerably larger one in a soil containing 2 m-equiv.5. Only small differences occurred in the ratio of 89Sr to calcium between lucerne and rye-grass. This comparison was not made beyond the first 6 months of growth.6. Experiments carried out with established pastures on four soil types indicate that 89Sr is more readily absorbed from the ‘plant-base’ than after incorporation with soil. Ploughing and reseeding may reduce the ratio of 89Sr to calcium in herbage by a factor of up to 4. This effect may be greater on mature swards.7. The liming of contaminated swards reduces the ratio of 89Sr to calcium in herbage by a factor of 2 to 3 regardless of the calcium content of the soil, and liming followed by ploughing and reseeding by a factor of 3 to 7.
A chemical study of soft fat in cross-bred pigs
Authors: Lea C. H. , Swoboda P. A. T. , Gatherum D. P. 
Published: March 2009

SUMMARYIodine values, melting (slip) points and fatty acid analyses for back (‘bung’) and perinephric (kidney) fats from 114 pure and cross-bred pigs are reported.In most cases the effects of breed were small, but half-Hampshire crosses showed a high proportion of pigs producing abnormally soft and highly unsaturated fats, though others were normal.Although a general correlation existed between iodine value and melting-point the relationship broke down in some cases, and the ratio of monoene to saturated fatty acids of carbon chain length 16 and 18 is suggested as a better chemical index of softness due to causes other than dietary lipid.
Soil phosphate values in relation to phosphate supply to plants from some Nigerian soils
Authors: Bache B. W. , Rogers N. E. 
Published: March 2009

SUMMARYPhosphate uptake and dry-matter yield from unfertilized pots and relative yield (ratio of unfertilized to fertilized yield) of Rhodes grass were used as plant indices of P supply from twenty-four soil samples from long-term manurial trials in Nigeria. Although measurements of the soil P quantity factor were generally the more important, intensity measurements also made a highly significant independent contribution to the P supply. Inorganic P (a quantity measure) combined with the log of P concentration in a saturation water extract (an intensity measure) gave a multiple correlation coefficient of R = 0·954*** with relative yield, accounting for 91% of its variation. The best single measure was resin-extractable P, which gave r =0·930*** for correlation with relative yield. Organic P did not appear to contribute to plant growth.
The response of seven barley varieties to inoculation in the field with different isolates of Cercosporella herpotrichoides Fron
Authors: Davies J. M. L. , Jones D. Gabeth 
Published: March 2009

SUMMARYSeven commercial barley varieties were inoculated with mycelial suspensions of different isolates of Gescosporella herpotrichoides. There were significant varietal differences in eyespot susceptibility. There were significant differences between isolates which originated from both wheat and barley. The yield of the varieties was reduced between 30 and 50% depending upon the isolate used. Significant interactions between isolates and varieties were found for the incidence of disease, its effect on tiller number and upon total yield.
Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude III. The response of mature and young rams to a thermal burden induced by exercise
Authors: Symington R. B. 
Published: March 2009

Mature and young Merino, Persian and Native rams were compelled to run 1 mile in 10–12 min. The response to the thermal burden induced by this exercise was measured in terms of body and skin temperatures, rate of respiration and length and temperature of the scrotum.1. Marked increases were recorded in every body response immediately after the exercise. Body, skin and scrotal temperatures returned to normal within 2 hr. but respiratory rate remained elevated for a further 4 hr.2. There were breed differences in the initial and subsequent measurement of every response. At 7.0 a.m. when there was no thermal stress body temperatures and rates of respiration were: Merino 102·9° F.; 3·-6 cyc./min. Persian 101·4° F.; 23·8 cyc./min. Native 102·1° F.; 28·9 cyc./min. Merino rams had the greatest ability to combat rising ambient temperature, Native rams the least. Persian rams recuperated quickest after exercise, Native rams slowest. The different responses of wool and hair breeds were apparently due to their coats. Merino fleece stabilized body temperature, did not aggravate the effects of exercise unduly and did not greatly hamper elimination of heat from the body after exercise.3. In all breeds respiratory evaporation was the principal thermolytic process. Rate of respiration was a sensitive indicator of thermal stress but it could not be used as an index of heat tolerance because the associated changes in respiratory volume were not known.4. Age was seldom of significant importance to determine response to thermal burden. In general young rams were affected less adversely by exercise and more adversely by rising ambient temperature than were mature rams. These differential effects were probably due to leggy conformation, low live weight and physical fitness in young rams on one hand, and incomplete development of the thermoregulatory system on the other.5. Increase in scrotal pendulance was related inversely to ability to maintain normal body temperature.6. In view of the influence of age and body conformation on the response to exercise it was questioned whether comparable heat tolerance indices could be obtained by this method.
Nitrogen studies in a coffee soil I. Seasonal trends of natural soil nitrate and ammonia in relation to crop growth, soil moisture and rainfall
Authors: Robinson J. B. D. 
Published: March 2009

1. The general seasonal trends of top-soil nitrate and ammonia-N, and growth of the coffee tree are described for conditions of both soil and climate which are representative of a large proportion of the coffee-producing area in Kenya.2. When rainfall is heavy and persistent at the beginning of a rains period soil nitrate-N levels decrease rapidly, partly because of leaching losses and partly through uptake by the crop. Under conditions of rainfall and cropping similar to those described for the first half of 1954, the flush of nitrate-N in the early part of the rains will not be detected under field conditions. When the onset of the rainfall season is more gentle and substantial water movement through the upper part of the soil profile does not take place, for example, Short Rains, 1954, nitrate-N values do not decrease rapidly and there is indirect evidence of the stimulatory effect of this type of rainfall on nitrate-N formation in a remoistened field soil.3. Rapid and substantial build-up of nitrate-N is shown to take place during intervening dry weather between the rainfall periods. This is particularly marked in the top 6 in. of the soil profile and is attributed to nitrate-N formation in the absence of leaching losses; to a decreased rate of uptake by the coffee tree in the absence of vigorous growth and to the physical movement of nitrate-N upwards into the top-soil.It may be inferred from the results that alternate periods of rain and sunshine, rather than continuous heavy rain, will favour high soil nitrate-N levels and a more satisfactory nitrogen nutrition of the coffee tree.4. During periods of very low soil moisture ammonia-N builds up in the dry top-soil.5. The sharp peak and rapid decline in the rate of coffee growth during the Long Rains period coincides with very low soil nitrate-N values although climatologically conditions for continued growth are still excellent. This suggests that low available soil nitrate -N may be at least partially responsible for this early and rapid decline in the growth rate.6. In the light of observed trends in nitrate-N and coffee growth the timing of fertilizer nitrogen application to mature coffee has been altered. During the Long Rains split applications are recommended with the particular object of maintaining a supply of readily available nitrate-N in the soil. An additional and supplementary fertilizer nitrogen application is also suggested in the Short Rains period.
The indirect estimation of the digestibility of pasture herbage II. Regressions of digestibility on faecal nitrogen concentration; their determination in continuous digestibility trials and the effect of various factors on their accuracy
Authors: Greenhalgh J. F. D. , Corbett J. L. , McDonald I. 
Published: March 2009

1. A mixed sward was divided into two areas receiving high (H) or low (L) levels of fertilizer nitrogen, and on two occasions, in spring and summer, herbage cut from each area was given to three steers in a continuous digestibility trial lasting 45 days. Digestibility and faecal nitrogen concentration were measured for each animal for each 24 hr. period, and equations relating these variables were calculated for each trial from the unit 24 hr. observations and from averages over three animals and over successive 2-, 3-, 5- and 9-day periods.2. In the two spring trials herbage digestibility remained constant for the first 12 days and then declined by about 0·4 units per day. In the summer trials digestibility declined throughout by 0—25 units per day. The nitrogen content of the herbage was consistently 25% higher for treatment H, and declined steadily throughout each trial.3. Both season of cutting and fertilizer treatment had a significant effect on the faecal index regressions obtained. Equations calculated from average values for three animals and 3 days predicted digestibility coefficients from 3% faecal nitrogen as follows: equation (1) spring H, 76·5; (2) spring L, 77·5; (3)summer H, 71·8; (4) summer L, 72·8.4. The joint residual standard deviation for equations (1) to (4) had the low value of ± 0·90 units of digestibility, indicating that ‘single-sward’ regressions are considerably more accurate than those embracing a great variety of herbages. Even greater accuracy was obtained when digestibility and faecal nitrogen concentrations were measured for periods longer than 3 days; in general, residual variance varied inversely with period length. Using values for individual animals in the regressions increased the residual variance slightly, but because differences between animals in the digestibility-faecal nitrogen relationship were small and generally nonsignificant, the increase was by a factor of the order of 1·6, not 3.5. Standard errors of prediction were calculated, although there is evidence to suggest that these underestimate the error of digestibility coefficients predicted for free-grazing animals. It is concluded that faecal index regressions are accurate enough for measuring digestibility per se in grazing experiments. In the measurement of herbage consumption, however, the experimental error is likely to be high, partly because indigestibility is the factor required to be predicted, but mainly because of large differences in appetite among similarly treated animals.