bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experiments on the effects of phosphate applied to a Buganda soil: I. Pot experiments on the response curve
Authors: Le Mare P. H. 
Published: March 2009

SUMMARYIn a pot experiment providing for rapid growth of sorghum plants in the red clay loam soils of the Cotton Research Station, Namulonge, in the Buganda Province of Uganda, large yield increases were obtained from added phosphate. In an uncultivated soil which had carried undisturbed natural vegetation (Pennisetum purpureurn)for at least 10 years the response curve had negative curvature throughout. In an arable soil, yields without added phosphate were very poor and the response curve was sigmoid in form. With the arable soil, liming did not modify the form of the response curve for added phosphate but at the heaviest dressing lime decreased yield.
The influence of diluents and processing time after ejaculation on the revival of deep-frozen bull spermatozoa
Authors: Martin I. C. A. 
Published: March 2009

For highest revival rates in experiments on the deep-freezing of bull spermatozoa to – 79° C., a period of incubation of the undiluted semen at 30° C. did not eliminate the need for overnight equilibration at 5° C. The addition of 1·25% fructose or arabinose to the diluent improved revival rates of non-equilibrated spermatozoa but these rates still did not equal those of equilibrated spermatozoa.Glycerol apparently penetrated spermatozoa rapidly and spermatozoa survived in glycerol solutions as high as 2·0m if 0·1m buffered citrate was also present. Omission of the citrate solutions caused immediate death of the spermatozoa.A one-ninth replication of a 37 factorial experiment showed that, by all scoring criteria, 40° C. was superior to 0° C. as a thawing bath temperature. A diluent containing 8% (v/v) glycerol was superior to either 4% or 6% if activity of spermatozoa after thawing was the scoring criterion, but there was no difference in the percentage of spermatozoa stained by congo-red-nigrosin when frozen in diluents containing these levels of glycerol.In the range of tonicity 80, 100 and 120% (0·9% NaCl = 100% tonicity), using the diluent composed of a mixture of fructose and citrate, there were more motile spermatozoa than in buffered citrate or fructose alone. Increasing tonicity had an adverse effect on revival rates of spermatozoa in the buffered citrate diluent. Spermatozoa stored chilled at 5· C. for periods up to 36 hr. prior to freezing survived best in the mixture of fructose and citrate.The investigation of the equilibration phenomenon showed that an improvement in survival after deep-freezing occurred if diluted semen was stored for up to 12 hr. after dilution, but this was not dependent on the presence of glycerol in the diluent during this ageing process.
A study of the development of two varieties of maize at Ibadan, Nigeria
Authors: van Eijnatten C. L. M. 
Published: March 2009

The very fast development of maize plants at Ibadan, Nigeria, has been described and an attempt has been made to obtain a better understanding of their development with the aid of a growth analysis. Two varieties of maize have been studied, which, again during this experiment, proved to have a very different yielding performance, in spite of a rather similar vegetative development. It was shown that Lagos White, the local variety, produced approximately 2000 lb./acre and ES 2 3000 lb./acre.From approximately the ninth week onwards the ear starts rapid development, and the retention of a larger functional photosynthetic area by the introduced variety ES 2, from the eighth week onwards, seems to be the major factor controlling its higher production of dry matter in the latter part of development, when compared with Lagos White.On the average, n.a.r. had similar values in both varieties and had similar deviations at various stages of development; external or internal factors could not be separated. The l.a.r. indicated that, certainly in the latter part of development, ES 2 plants and Lagos White plants had a similar leaf area per gramme of dry matter; but ES 2 had more of both. This factor stresses the similarity of efficiency in both photosynthetic mechanisms.The l.a.r shows in clear terms the difference between the two varieties grown at equal spacing. The variety ES 2 still increased its leaf area with its additional laminae, when Lagos White, which had a more rapid loss of leaf by senescence, had come to a standstill. The more pronounced longevity of the photosynthetic area in ES 2 appears therefore the major determinant of the higher production of dry matter by this variety. The possible significance of variation in longevity of leaves had been pointed out already in 1929 by Boonstra, who found some evidence of an association of longevity of leaves and high yields in four varieties of oats.
The effect of time of irrigation on the growth and yield of transplanted rice plants (Oryza sativa L.)
Authors: Enyi B. A. C. 
Published: March 2009

1. Continuous waterlogging and 4 weeks' waterlogging immediately after transplanting produced plants with higher leaf and shoot numbers.2. There was no difference in the final shoot number between plants continuously waterlogged and those waterlogged for 4 weeks, immediately and 4 weeks after transplanting. The shoot mortality was higher in the continuously waterlogged plants and those waterlogged for 4 weeks immediately, 8 weeks and 12 weeks after transplanting than in those waterlogged for 4 weeks, 4 weeks after transplanting.3. Continuously waterlogged plants and those waterlogged for 4 weeks, 4 weeks after transplanting, were taller than those waterlogged for 4 weeks, immediately, 8 weeks and 12 weeks after transplanting.4. Leaf area per bucket, leaf area per shoot and per leaf lamina were higher in continuously waterlogged plants and those waterlogged for 4 weeks, 4 weeks after transplanting, than in those waterlogged for 4 weeks immediately, 8 weeks, and 12 weeks after transplanting.5. Continuous waterlogging and waterlogging for 4 weeks, 4 weeks after transplanting, increased the physiological age of the plants as evidenced by earlier ear emergence and grain ripeness.6. Fresh-weight yield, yield of grain and panicle were greater in continuously waterlogged plants and those waterlogged for 4 weeks, 4 weeks after transplanting, than in those waterlogged for 4 weeks immediately, 8 weeks and 12 weeks after transplanting.7. The critical period for waterlogging in the cultivation of the rice variety studied is 4 weeks after transplanting and waterlogging applied during this critical period for 4 weeks favours higher yield of grain than when applied for the same period earlier or later than this period. Where water supply is limited the plants should only be waterlogged at this period and the soil kept moist throughout the remaining growing period. However, where there is enough water to waterlog the plants for 8 weeks this should be started immediately after transplanting.
The efficiency of beef production in terms of carcass-weight increase as influenced by the ration concentration and the age of steers
Authors: Luitingh H. C. 
Published: March 2009

The carcass-weight increase of beef steers of various ages receiving fattening rations of different roughage: concentrate ratios was calculated by making use of the average dressing percentage of a control group slaughtered at the beginning of the experiment.It is shown that, in terms of t.d.n./100 lb. carcass-weight increase, which is probably the more accurate measure of efficiency, the 2-year-olds were better feed converters than the calves. When the criterion was t.d.n./100 lb. live-weight increase the calves were superior. Ration B (1 concentrates: 1 roughage) was utilized most efficiently in terms of calculated carcass-weight increase, followed in a descending order by the high-concentrate ration C and the high-roughage ration (ration A).The relationship of live-weight increase to carcass- weight increase as calculated is discussed. The proportion of live-weight gain laid down as carcass varied with age, growth rate and type of ration. This percentage variation ranged from 57% in slow-growing calves to 81% in fast-growing 3-year-olds. On the average, calves converted 61% of their live-weight gain into saleable carcass, the 2-year-olds 70·8% and the 3-year-olds 75·9%. The steers on the A (high roughage) ration converted 65·7% of live-weight gain into carcass, those on the C (high concentrate) ration 71·5% and those on the B (1 concentrate: 1 roughage) 69·2%. Reasons for these differences are discussed in terms of so-called differential growth.The live weights and carcass weights of steers were plotted and the regression equationwhereYis carcass weight andXis live weight, was derived. The correlation coefficientr= 0·98 and the slope of the curve indicated that for an increase of 1% in the live weight of the steers, the carcass weight increased by 1·13%.Several methods of expressing ‘efficiency of the fattening’ were applied to the data and the results are discussed. The methods were unanimous in selecting the steers on the B ration as the most efficient followed by those on ration C and the poorest were those on the A ration. Methods based on live-weight increase showed the calves, but those based on carcass-weight increase the 2-yearolds, as the most efficient. Results obtained by applying the Efficiency Quotient and Efficiency Index suggested that the older animals wero the more efficient. They differed from all other methods since these indicated that efficiency declined with age.Efficiency values calculated by different formulae vary and no efficiency index has yet been evolved that will embrace all the variable factors which may have an influence on the efficiency of growth and fattening.
The influence of dietary concentration of calcium and phosphorus on their retention in the body of the growing pig
Authors: Mudd A. J. , Smith W. C. , Armstrong D. G. 
Published: March 2009

SUMMARYThree gilts and three castrated males weighing 23 kg live weight were given four semi-synthetic diets containing increasing amounts of Ca and P. The Ca and P contents (% dry basis) and Ca:P ratios for the four diets were A, 0·30, 0·38, 1:1·27; B, 0·58, 0·68, 1:1·17; C, 0·94, 1·13, l:l·20; D, 1·16, 1·47, 1:1·27. Each animal was slaughtered at 41 kg live weight and the whole body contents of Ca and P determined. Six pigs were slaughtered at 23 kg live weight and their bodies also analysed for Ca and P contents. Dietary concentration of Ca and P did not influence rate or efficiency of live weight gain nor carcass characteristics. Net retention of Ca and P increased with increasing dietary concentration of these elements. Analyses of isolated femurs suggested that optimal mineralization of the bone was associated with a net retention of 8·2 g Ca/kg live weight gain. The data were used to calculate a value of 32·9 mg/kg live weight/day for the endogenous loss of Ca in pigs of 23–41 kg body weight. The values have been used to compute a mineral requirement of dietary calcium which is in excellent agreement with that derived from estimates in the literature.
Some wool follicle characteristics in crossbreds between Egyptian coarse wool sheep and long and fine-wool breeds
Authors: Ragab M. T. , Marai I. F. M. 
Published: March 2009

SUMMARYInternal and external follicle diameters of both primary and secondary follicles of Texel x Ossimi and Merino x Barki ewes were greater, at birth, than those in either respective parent breed; the density of primary follicles at birth was less in the cross-breds than in the parental breeds, for both crosses. There was a greater increase of follicle diameter with age in the Egyptian breeds, and mean follicle diameters of the crossbreds were intermediate between those of parent breeds at ages of 3–6 months and above.Grading up Ossimi sheep with the Caucasian Merino resulted in progressive decrease of mean internal follicle diameter. The F2, with more merino blood, had a greater frequency of the smallest diameter follicles than had the F1.
Growth of cross-bred Dorset Horn lambs from East African Blackheaded Sheep
Authors: Trail J. C. M. , Sacker G. D. 
Published: March 2009

SUMMARYThe growth of ½ ⅝, and ¾ bred Dorset Horn lambs was examined in Western Uganda. These were produced by mating Dorset Horn rams with East African Blackheaded, ¼ bred Dorset and 1/2 bred Dorset females respectively.The influence of type of birth (single or twin) was maximum at the end of the main 2-month suckling period and progressively decreased to 11 months of age. The influence of maternal age did not decline as lambs grew older. Dorset ewes, ¼ and ½-bred, had superior milking capabilities, as measured by lamb growth at 2 months of age, to indigenous ewes. Lambs, ⅝ and ¾-bred, were 26 % heavier than ½-bred lambs at 2 months of age, and as all three types grew at the same rate from 2 to 11 months, ⅝- and ¾-bred lambs retained this initial advantage.
Statistical research on the fate of dietary mineral elements in dry and lactating cows: I. Calcium
Authors: Paquay R. , Lomba F. , Lousse A. , Bienfet V. 
Published: March 2009

SUMMARYStatistical analyses were carried out on the data obtained under strictly controlled conditions in metabolism stalls with 41 different rations fed to 127 adult non-pregnant dry cows, and with 14 other different rations fed to 35 adult non-pregnant lactating cows that had calved 2–6 months earlier and whose daily milk production ranged from 11 to 20 kg. The authors have calculated and studied the correlations between faecal and urinary calcium losses, calcium excretion in the milk, digestible calcium, and calcium balance, and the 75 other nutritive factors which were analysed for each of the 55 above-mentioned experimental diets. The results showed that calcium metabolism is regulated in the digestive tract, and the fact that the lactation calcium requirements increase at the same time as the amounts of digestible calcium and the calcium balance corroborates this statement. But except for this endogenous factor of resorption, the fate of the dietary calcium does not depend on the ingested amounts but on the nature itself of the components of the diets and their proportions in the diets. Cereals, and especially barley, have from this point of view a particular beneficial effect. These factors act on the absorption of calcium and thus directly on the balance, since the daily urinary excretion of calcium is generally small and independent. It has also been demonstrated that the balance is not inevitably negative in cows with a daily milk production of 11–20kg, and that a careful composition of the rations should enable one to equilibrate it.The other nutritive factors do not work on calcium utilization, but a close parallel exists between digestibility, urinary excretion and balance of both calcium and magnesium.
Copper sulphate and antibiotics as feed additives for early weaned pigs
Authors: Livingstone R. M. , Livingston D. M. S. 
Published: March 2009

SUMMARYCitric acid and three antibiotic-type substances—zinc bacitracin, tylosin and formosulphathiazole—were included in dry-meal diets for early weaned pigs up to 20 kg live weight. Two experiments were carried out and in each copper sulphate as 0.1 % of the diet was tested.In the first experiment the diets were supplemented with citric acid, copper sulphate or both citric acid and copper. The pigs given the diet containing both citric acid and copper tended to have the greatest daily live-weight gains and there was a similar trend in favour of the diet containing copper sulphate alone, but these advantages did not reach significance.In the second experiment diets with or without copper sulphate were supplemented with either Zinc Bacitracin, Tylosin or formosulphathiazole. All three ‘antibiotics’ had beneficial effects on rates of gain and feed-conversion efficiency, resulting in average. increases of 15% and 10% respectively. Copper sulphate did not improve the performance of the pigs when included in the basal diet with or without an ‘antibiotic’ and there was no interaction between the copper supplement and any of the other supplements.The performance of the pigs after 20 kg live weight under standard conditions showed little evidence in these experiments that the beneficial effects of feed additive use before this weight persisted during growth to 90 kg live weight or that any of the major measures of carcass quality were affected by the early treatment.
Some effects of wintering yearling beef cattle on different planes of nutrition: I. Live-weight gain, food consumption and body measurement changes during the winter period and the subsequent grazing period
Authors: Lawrence T. L. J. , Pearce J. 
Published: March 2009

An experiment is described in which the growth rate and conformation changes of cattle subjected to different levels of nutrition during their yearling winter, and then re-alimentated on grass, were studied.For this purpose thirty-six Sussex x Shorthorn steers between 38 and 52 weeks of age were randomly distributed on the basis of live weight into three groups, each of twelve animals.
The productivity of five grass species at six levels of compound fertilizer application II. Crude-protein production
Authors: Henderson J. L. , Edwards R. S. , Hammerton J. L. 
Published: March 2009

1. Data on the crude-protein content and crudeprotein production of five grass species (each sown with white clover) over the period 1954–56, at six levels of compound fertilizer application, are reported. Perennial rye-grass (S. 101), meadow fescue (S. 215), timothy (S. 48), cocksfoot (S. 26) and bent (N.Z. Browntop) were sown in 1953 at appropriate seed rates, each with 2 lb./acre S. 100 white clover. The fertilizer treatments were 0, 1, 3, 5, 7 and 9 cwt./ acre of a compound of composition 10% N, 4%P2O5, 9·5% K2O applied in the early spring of each of the years 1954–56. The swards were cut three times a year in 1954 and 1956, but only two cuts were possible in 1955.2. Bent mixtures had a higher crude-protein content than any other mixture in all years and (with one exception) at every cut within years. Differences between other mixtures were smaller and often erratic, though timothy invariably had the lowest crude-protein content at the second cut and cocksfoot at the third. Application of the fertilizer raised the crude-protein level of the herbage at the first cut, but depressed it in subsequent cuts.3. The bent mixture gave the highest yield of crude-protein per acre followed by the timothy mixture, while the lowest yield was produced by the perennial rye-grass mixture. The bent mixture differed from all others in its distribution of crudeprotein production over the season, producing less at the first cuts and more at the second and third cuts. This reflects its pattern of production of dry-matter. Response to spring application of fertilizer in terms of crude-protein yield declined rapidly from cut to cut. Over the whole period of the experiment 1 cwt./acre/ annum of fertilizer containing 10% N gave a response of about 0·5 cwt. crude-protein/annum.
Variation in efficiency of food utilization in twin calves I. Individual variation and age trends in efficiency
Authors: Taylor C. S. , Watson J. H. , Young G. B. 
Published: March 2009

Efficiency of food utilization from 2 to 18 weeks of age has been examined in 12 MZ and 7 DZ pairs of twin calves fed standard rations. Mean efficiency reached a maximum at about 6 weeks of age; weaning brought about a rapid decline followed by a recovery. Animals became more alike in efficiency as their ages increased.Those animals least efficient shortly after birth were most adversely affected by weaning, although they tended to be relatively more efficient when fully established on either milk or solid food.Relative to the fairly closely replicated age-efficiency trends of identical twins, different pairs followed different trends. These trends, which primarily reflected the variable success with which the calves adapted to new diets, were subject to some genetic control.
The use of hexoestrol for beef production from zebu cattle under ranch conditions in Tanganyika
Authors: Hutchison H. G. , Robb J. M. 
Published: March 2009

1. Three groups of twenty, 3½ to 4-year-old zebu steers, replicated four times in each quarter of the year, were used to examine the effects of 30 and 45 mg. hexoestrol implants on their beef production, under ranch conditions in Tanganyika.2. Significant advantages in mean live-weight gains of 20·8–47·3 lb. for 30 mg., and 9·8–47·3 lb. for 45 mg., were obtained when treated at any time of the year; but during the dry-season implantation is contra-indicated as initial response is adverse although followed by pronounced recovery when pasture conditions improve.3. There was no significant difference between dosage rates in growth response, but on smaller steers, and as the pasture deteriorated, 45 mg. showed signs of being excessive.4. Duration of significant response was about 3 months during the period of adequate grazing, but was delayed to 5 months, and probably longer, during the dry season.5. Steers were slaughtered 6–9 months after implantation and at that time showed: no significant difference in dressing percentage, shrinkage in store, proportion of bone, or carcass grade; there was significantly less fat, and more lean, but increased proportion of moisture in the muscle accounted for the extra proportion of lean in the sample joints.Treated carcasses were significantly longer by 1·0% and highly significantly larger in circumference of hind quarter by 2·0%.
Establishment studies VI. The effect of method of establishment on long-term leys in the first harvest
Authors: Charles A. H. 
Published: March 2009

1. The method of establishment markedly affected the yield of red clover in the first harvest year, the highest yield being obtained when a cover crop was used, in the absence of which red clover yield was reduced by frequent grazing during establishment. White clover made little growth in the first harvest year; the yield was best without a cover crop under frequent grazing during establishment.2. Nitrogen applied in the seed bed did not affect the growth of red clover in the first harvest year, but depressed the white clover under infrequent defoliation without a cover crop. There was no significant effect under the other management.3. The total yield of red and white clovers was lower, when sown with the rapidly establishing ryegrass or ryegrass-dominant general-purpose mixtures, than with cocksfoot or timothy mixtures. Weed growth, although not prominent, was far greater in the timothy and cocksfoot swards than in those based on ryegrass.4. A close parallel existed between the growth of red clover and the dry matter and yield of crude protein. The highest figures were recorded when management during establishment had favoured the growth of the red clover.5. Nitrogen applied in the seed bed reduced the percentage of crude protein in all mixtures in the spring and autumn grazings, and in the hay crop of the first harvest year. Management which encouraged the growth of red clover increased the crude protein percentage of herbage in the spring and autumn, but depressed it in the aftermath cut.6. A number of interactions occurred when the relative yields of dry matter and crude protein of mixtures in the first harvest year were modified by treatments applied during establishment. There are significant indications that the method of establishment is a factor to be considered in evaluating various mixtures.