bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of rates and time of application of nitrogenous fertilizer on barley in south-east Scotland
Authors: Holmes J. C. , Gill W. D. , Rodger J. A. B. 
Published: March 2009

1. Two series of simple nitrogen manuring trials, one on level of sulphate of ammonia applied to the seedbed at twenty-two centres and the other on the time of top dressing with ‘Nitro-Chalk’ at nineteen centres, were conducted on commercial farms in south-east Scotland during 1954 to 1957.2. The optimum level of sulphate of ammonia varied with season and farm type. The optimum dressing was at least 0·9 cwt. N/acre in the dry season of 1955, and in the other years was estimated to be 0·9 cwt. N/acre on arable farms and about 0·-25–0·4 cwt. on ley rotation farms when the barley did not follow sheeped turnips. In the latter event no fertilizer was best.3. The nitrogen content of the grain increased little until after the 1 cwt. sulphate of ammonia level, although the optimum yield was not obtained in many experiments without some rise in the grain nitrogen content.
The influence of huddling and body size on the metabolic rate of the young pig
Authors: Mount L. E. 
Published: March 2009

1. The oxygen consumption of young pigs from 1 to 37 days of age has been measured in a closed circuit respiratory metabolism chamber, over the environmental temperature range 4–37° C.2. The values obtained for single pigs alone in the chamber have been compared with the results of measurements on groups of pigs 3–6 days of age taken together.3. It has been found that as environmental temperature falls below 30° C. and the grouped pigs huddle together, oxygen consumption per kg. for the group becomes smaller than values for single pigs of the same individual weight, and corresponds more with results from the larger single pig.4. Rectal temperature is maintained in pigs of the group at a lower energy cost than that required for the single pig, the saving in energy expenditure becoming proportionately greater as ambient temperature falls.5. These results are discussed in relation to body size and skin temperature.
Sweating in cattle VI. Density of sweat glands and its relationship with cutaneous evaporation
Authors: Taneja G. C. 
Published: March 2009

Two calves (Zebu × Australian Illawara Shorthorn and Shorthorn) of about 7–8 months of age were exposed to controlled atmospheric conditions. Cutaneous evaporation from the shoulder and belly areas of these calves was measured by the capsule method. Density of the sweat glands in the shoulder and belly areas of these calves was measured, using a biopsy punch. Density was estimated by counting the hair follicles.(1) The Zebu cross sweats more than the Shorthorn, at least from the shoulder area, and this is related to its higher sweat gland density as compared with that of the Shorthorn.(2) In the Zebu cross cutaneous evaporation from the shoulder area is greater than that of the belly and this is associated with the differences in the number of sweat glands.(3) In the Shorthorn cutaneous evaporation is the same from both shoulder and belly areas and the number of sweat glands in these regions is also the same.
Effects of time and rate of nitrogen application on tillering, ‘sharp eyespot’ (Rhizoctonia solani) and yield in winter wheat
Authors: Bremner P. M. 
Published: March 2009

SUMMARYVarious rates of nitrogen fertilizer were applied in early and late spring to two densities of winter wheat to examine their effects on grain yield and its components. A severe attack of ‘sharp eyespot’ (Rhizoctonia solani) allowed an assessment of the effects of the treatments on the incidence of this disease.The disease level was much higher where nitrogen was applied early and increased with increase in nitrogen up to 120 units applied; it was slightly higher at the higher density. Grain yield was slightly greater where nitrogen was applied late; early application gave more, but smaller, ears. Main shoots produced at least 70% of the grain in the high-density plots but less than 50% at the low density. Tillers appearing after early March contributed little to grain yield at the higher density but substantially at the lower one. Tillers produced after early April died without heading. In general, the chances of survival of a tiller diminished with delay in the time of its appearance, but some early tillers died while later ones survived and produced ears. The chances of survival of later tillers were greater at low density and high rates of nitrogen.
Dietary effects on beef composition: III. Weight, composition and potassium–40 content of fat-free muscles
Authors: Judge M. D. , Firth N. L. , Johnson H. R. , Kessler W. V. , Harrington R. B. , Garrigus R. R. 
Published: March 2009

SUMMARYThe effects of several dietary regimens on the fat-free mass and the dry-matter, ash and potassium-40 content of selected bovine muscles were estimated. Muscle data from 104 half-sib Angus steers were secured at several stages of growth and after several feeding regimens. The results indicated that a hay diet, by comparison to a higher energy silage diet in the early feeding period (216–340 kg live weight), suppressed the fat-free weight, reduced the dry-matter content and increased the ash content of several muscles. These effects of early diet were reversed, however, when the animals were subsequently fed higher-energy rations and slaughtered at heavier weights (409 and 454 kg live weight). Data on potassium-40 gamma emissions by composite muscle samples confirmed the existence of age- or weight-associated decreases and suggested possible dietary influences on potassium levels in bovine muscles. The trends in these data indicated that low dietary energy (hay feeding) in the early feeding period delayed the decline in muscle potassium that normally accompanies maturation.
Biochemical appraisal of a milk diluent for semen
Authors: Friis Jakobsen K. , Mann T. 
Published: March 2009

1. A study was made of the effects of a milk diluent on bull, ram and boar spermatozoa. Respiration and fructolysis of spermatozoa were used as the two main criteria of sperm activity. The milk diluent was a standardized and commercially available milk product, consisting of sterilized and homogenized milk, supplemented with milk fat.2. The rate of oxygen uptake measured manometrically in the presence of air was increased by the addition of the milk diluent throughout the entire incubation period. Fructose utilization was assessed by the rate of lactic-acid production. The rate of the anaerobic lactic-acid formation was higher in the presence of the milk diluent during the later stages of incubation.3. The effect of the milk diluent on sperm respiration was most striking in experiments with the sperm-rich portion of boar ejaculate obtained by fractionated collection. A somewhat less marked effect was observed with bull semen, and in ram semen the effect was comparatively weak.
Reproductive rates and milk yield of Kenana cattle in Sudan
Authors: Alim K. A. 
Published: March 2009

An analysis has been made of the reproductive rates and milk yield of Kenana cattle in a closed dairy herd in Sudan.The average age at first calving was 38·4 months and calvings were most frequent between September and December.The average length of productive herd life of cows was 5·42 lactations.The average interval between successive calvings was 395 days, and this was influenced by years and age.The mean generation interval was 6·72 years.The average milk yield in 224 days was 338 gal. with a standard deviation of 152 gal.There was a close relationship between milk yield and lactation length; r = 0·866 ± 0·013.Milk yield increased by age until the fourth lactation when it was about 137% of the first lactation. The rate of increase in yield between first and second lactation was highest and amounted to 22%.Year of record had a pronounced effect on milk yield.Month of calving had a slight effect on milk yield.The repeatability estimates of single records milk yield, calving intervals, lactation periods and dry periods were 0·432 ± 0·046, 0·058 ± 0·059, 0·192 ± 0·058 and 0·069 ± 0·065, respectively.The increase in repeatability estimates between earlier and later successive milk yield records was accompanied by a decrease in the coefficients of variation of these records.The heritability of a single record milk yield was 0·239 ± 0·245.The rate of annual genetic superiority in milk yield of dams of cows and dams of bulls was found to be 0·74% of the herd average.
Relationship between levels of iodine and cyanogenetic glucoside in pasture and the productive performance of sheep
Authors: Flux D. S. , Butler G. W. , Rae A. L. , Brougham R. W. 
Published: March 2009

This paper describes an experiment designed to test the goitrogenic effect of white clover (Trifolium repensL) in ewe lambs grown and taken through a complete reproductive cycle. The sheep were setstocked on four pastures made up of perennial ryegrass and short-rotation rye-grass, both alone and together with cyanogenetic white clover. Since these species differ in iodine content when grown on the same soil, there were probably differences in dietary iodine intake of the sheep in the four groups. Half the animals in each group were injected intramuscularly with an iodinated poppy-seed oil to serve as an iodine depot.At slaughter, 19 months from the commencement of the experiment, thyroid weights indicated a goitrogenic action in the non-injected ewes grazing short-rotation rye-grass and white clover and to a lesser extent in the non-injected ewes grazing perennial rye-grass and white clover. There was evidence of a slight goitrogenic action in noninjected ewes grazing perennial rye-grass. The thyroids of non-injected ewes had similar iodine contents, lying within the range of 0·23–0·29% of the dry weight.In injected ewes, the total iodine content of the serum was three to four times higher than with non-injected ewes and the iodine content of the thyroids was three times greater. All injected ewes had thyroids of normal weight.No effects of iodine supplementation on growth, reproduction or wool production were found.Lambs born to the ewes in the fifteenth month of the experiment were slaughtered when 3–5 months old, the age varying with pasture treatment. Thyroid weights indicated a goitrogenic effect from the clover-containing pastures.
Alteration of porcine skeletal muscle myoglobin by the environment
Authors: Thomasf N. W. , Judge M. D. 
Published: March 2009

SUMMARYAnimals reared in constant ambient temperatures had significantly more skeletal muscle myoglobin than those reared in alternating temperature environments when the humidity was moderate or high. These differences did not exist when humidity levels were low. Comparisons ofthe effect of humidity level in constant ambient temperatures revealed high myoglobin in pigs subjected to moderate as compared to low humidity at 27°C, but humidity effects were nonexistent when the ambient temperature was 21 or 32° C. It is postulated that animals reared in alternating temperatures experienced intermittent and persistent development of tissue hypoxia and, asa consequence, had reduced aerobic metabolic pathways in muscle as compared to animals rearedinconstant ambient temperatures.
Studies on the adaptability of three breeds of sheep to a tropical environment modified by altitude I. The annual fluctuation in body temperature and body temperature increase between 6.30 a.m. and 12.30 p.m.
Authors: Symington R. B. 
Published: March 2009

Early morning and midday body temperatures of rams and ewes of three breeds of sheep were measured once weekly for a period of 10 months in Northern Rhodesia and 12 months in Southern Rhodesia.1. In all breeds seasonal fluctuations in body temperature were due to concurrent fluctuations in ambient air temperature.2. Mean annual body temperatures were: Merino 102·2° F.; Persian 101·7° F. and Native 101·7° F. Wool and hair breeds differed considerably in their early morning temperatures and in their body temperature increases from 6.30 a.m. to 12.30 p.m. Mean annual values for these measurements were Merino 101·73 and 1·92° F.; Persian 100·81 and 1·83° F.; Native 100·73 and 1–92° F. At all times Merinos showed markedly greater uniformity of body temperature than either hair breed. There was no evidence to show that the thermoregulatory mechanisms of these animals had been stressed unduly.3. Sex had no consistent effect on body temperature or on rise in body temperature.In general, lactating ewes showed a significantly higher initial body temperature than either empty or pregnant ewes, but the respective heat tolerances as measured by body temperature increase did not differ appreciably. Body temperature differed little in empty and pregnant ewes.4. Although the youngest group of ewes in each breed showed the highest early morning temperature, there was no evidence that heat tolerance was less in young than in old animals.5. Black-coated Native ewes had higher initial body temperatures and a smaller body temperature increase during the summer months in Southern Rhodesia than brown or broken-coloured Native ewes. These effects were due to differences in coat density rather than to differences in coat colour or skin pigmentation.6. In all breeds the magnitude of the diurnal and annual variation in body temperature was different in Northern and Southern Rhodesia. Differences were largely of climatic origin but low plane of nutrition in Southern Rhodesia possibly reduced critical body temperature and impaired thermoregulatory ability.
The effect of microdoses of ionizing radiation on poultry ontogenesis
Authors: Kushner H. F. , Dobrynina A. Ya. , Kostin I. G. , Zubareva L. A. , Samoletov A. I. , Salganik M. G. 
Published: March 2009

An insignificant short-term increase in the natural dose of ionizing radiation during the embryogenesis period is beneficial not only for the embryonic development of the chicks, but also for their postembryonic growth and development as well as the egg production of the pullets.Irradiation of incubated eggs with microdoses of radioactive radiations is another possibility for the utilization of atomic energy bringing about an improvement in the economically useful properties of poultry.
The effect of changing plant density on floral initiation and development of barley (cv. Sultan)
Authors: Leakey R. R. B. 
Published: March 2009

SummaryBarley plants were grown at low, high, increasing and decreasing densities in an attempt to manipulate the environment. The effects on tiller production and development were measured.Increasing density with time had less effect than decreasing it. Tiller number was the most plastic character, tiller production being earlier in those plants which emerged into low density, being delayed or inhibited in other treatments. The number of spikelets/ear and the length of the inflorescence were found to be less stable characters than the stage of ear development. Percentage spikelet survival showed a downward trend, with increasing density stress.
An assessment of the energy requirements of the pregnant ewe using plasma free fatty acid concentrations
Authors: Robinson J. J. , Fraser C. , Bennett C. 
Published: March 2009

SummaryAn experiment was conducted in which 57 North Country Cheviot ewes, bearing variable foetal loads, were offered different amounts of feed intake during the latter half of gestation. Plasma free fatty acid (FFA) concentrations were estimated at 10-day intervals during the last 55 days of gestation. From the relationship between FFA concentration, energy intake, lamb birth weight and ewe body weight, estimates of the energy requirements of the pregnant ewe were predicted.The additional metabolizable energy (ME) intake above maternal maintenance required to prevent elevation of plasma FFA concentrations above a predetermined basal level 5 days pre-partum was calculated as 335 kcal/kg lamb birth weight.The results obtained from the use of plasma FFA concentrations in assessing the energy requirements of the pregnant ewe are discussed in relation to those obtained by other methods.
Studies on the Northern Rhodesia Hyparrhenia veld Part II. Seasonal milk production using natural veld
Authors: Smith C. A. 
Published: March 2009

A description is given of a double change-over, grazing trial designed to test the value of Hyparrhenia veld grazing for milk production during the rains.Three feeds were offered to lactating cows, and the effects of qualitative differences between the feeds were measured on milk yields. The treatments were:
Environmental temperature and the energy metabolism and heat emission of steers
Authors: Blaxter K. L. , Wainman F. W. 
Published: March 2009

1. The energy metabolism and heat emission of two steers was determined at the maintenance level of nutrition in an environment of – 5, 5, 15, 25 and 35° C. and at a submaintenance level of nutrition in environments of – 5 and 19° C.2. Shivering was observed at temperatures of – 5 and + 5° C. in both animals. Respiratory distress occurred at 35° C. being more severe in one animal than in the other. The animals stood for longer periods at the extreme temperatures.3. The digestibility of food increased slightly as environmental temperature increased. Losses of energy as methane and in urine did not change in response to environmental temperature.
The effect of time of application of phosphate and potash on sugar beet
Authors: Adams S. N. 
Published: March 2009

1. Twenty-nine experiments on sugar beet in 1957–59 compared ploughing-down of phosphate and potash in the previous autumn with spring application before the seed-bed preparations.2. On average, spring application gave a higher yield of sugar and tops than ploughing-down, both in the wet summers of 1957 and 1958 and in the dry summer of 1959.
Competition between natural populations of Dactylis glomerata
Authors: Eagles C. F. , Williams D. H. 
Published: March 2009

SummaryThe competitive abilities of two natural populations of Dactylis glomeratafrom Norway and Portugal were studied under three controlled environments, 7 °C with an 8 h photoperiod, 20 °C with a 16 h photoperiod, and 30 °C with a 16 h photoperiod. The temperature and daylength treatments affected both the growth habits and the relative competitive abilities of the populations. At 7 °C, 8 h photoperiod the Norwegian population became prostrate and was suppressed in mixed culture compared with its performance in monoculture, and an increased specific leaf area indicated competition for light. At 30 °C, 16 h photoperiod the Norwegian population was more erect than the Portuguese, and more aggressive, with a better performance in mixed culture than in monoculture. The performance of the Portuguese population was not affected significantly either by culture or by environment. At 20 °C, 16 h photoperiod, however, the Portuguese population was suppressed, while the Norwegian population performed better in mixed than in monoculture. This yield increase of the Norwegian population was greater than the decrease of the Portuguese population, and so the mixed culture yielded significantly more than the mean of its component monocultures, whereas at 7 and 30 °C the mixed culture yielded no more than the mean of its monocultures. The physiological basis of these competitive effects is discussed.
Infertile bulls versus steers: III. Carcass characteristics
Authors: Price M. A. 
Published: March 2009

SummaryThe carcass characteristics of a total of 43 infertile bulls were oompared with those of 42 steers from five independent trials. In most cases there was no significant difference between the bulls and the steers for dressing percentage, or fleshing index. Bulls were generally found to have greater hide percentages than steers, the difference being very highly significant (P < 0·001) in one of the trials and significant (P < 0·05) in another. Eye musole area expressed relative to caroass weight was greater in the bulls, the difference being significant (P < 0·05) in three of the trials. The depth of fat over the eye musole and the hind to fore-quarter weight ratio were greater in the steer carcasses. Head weights were found to be significantly greater (P < 0·05) and caul and kidney fat weights less (P < 0·05) in bulls than in steers in the one trial where these parameters could be measured.Carcass composition was estimated by the three-rib sample joint teohnique in four of the trials, and in these the bulls had a greater percentage of bone and muscle, but a lower peroentage of fat than the steers, the differences being significant in most oases. In the fifth trial composition was estimated by half carcass dissection. This, too, showed bulls to have a greater percentage of bone and muscle and a lower percentage of fat, the differences being highly significant (P < 0·01) and very highly significant (P < 0·001) respectively. On a fat-corrected basis the estimated retail value of the carcasses favoured the bulls by about $20.00 each.The studies, conducted over a range of nutritional conditions, showed that non-castration favoured muscle growth while suppressing fat deposition, and that this advantage was more pronounced when growth rates were high.
Longevity of ram sperm in various diluents and at different dilution rates
Authors: Schindler H. , Amir D. 
Published: March 2009

The effect of various diluents and different dilution rates on the maintenance of motility of ram sperm during storage at 4° C. was tested. Their efficiency was determined by half-life periods and total survival times of the sperm.A yolk-glycine-citrate diluent maintained sperm motility for a longer period than did yolk—fructose—phosphate, yolk-citrate, cow's milk and ewe's milk, with or without yolk. This diluent has the advantage that the sperm is clearly visible under the microscope, and no sedimentation of any component occurs.A modified IVT diluent prolonged the total life span of the sperm, but caused a faster motility decline in the first part of the storage period.
The effect of pattern of protein intake and level of energy intake on the performance and nitrogen utilization of the ewe
Authors: Robinson J. J. , Fraser C. , Corse Elizabeth L. , Gill J. C. 
Published: March 2009

SUMMARYAn experiment was carried out in which each of thirty-six ewes was offered one of six dietary treatments from the 30th to the 140th day of gestation. The treatments supplied two levels of metabolizable energy (ME) intake (128 and 116 kcal/kg W0.75/day) each at three patterns of protein intake, namely equal increments at 22 day intervals, equal decrements at the same intervals and a constant daily intake throughout. The protein intake patterns supplied a mean daily intake of digestible crude protein of 3·74 g/kg W0.75/day. Nitrogen balances were carried out on four ewes from each dietary treatment during the last 10 days of each 22 day period.Thirteen ewes randomly distributed on all dietary treatments were barren. Mean rate of live-weight gain in the pregnant ewes was 123 g/day compared with 66 g/day in the non-pregnant ewes and was not significantly affected by treatments. Lamb birth weights adjusted to the basis of twins were 3·83, 4·02 and 3·56 kg for the increasing, constant and decreasing patterns of protein intake respectively.Within patterns of protein intake there were no significant differences in nitrogen retention between pregnant and non-pregnant ewes until after 90 days of gestation. Thereafter retention increased in the pregnant ewes offered the constant and increasing patterns of crude protein and remained constant in the non-pregnant ewes. During the same period the retention of both pregnant and non-pregnant ewes on the decreasing pattern decreased.The effects of both energy and protein intake on nitrogen retention in early and late pregnancy were assessed by multiple regression analysis. The results are discussed in relation to other recent findings.