bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of gene effects in three wheat crosses
Authors: Singh S. , Singh R. B. 
Published: March 2009

SummaryThe joint scaling test of Cavalli (1952) and the six-parameter procedure of Jinks & Jones (1958) were applied to test the adequacy of the additive-dominance model and to estimate various main and interaction gene effects for five characters, namely, final plant height, ear length, number of spikelets per spike, number of grains per spike and yield per plant, in three wheat crosses (Kalyan Sona × Norteno 67, Norteno 67 × WL 212 and K. Sona × Moti). Goodness of fit of the model varied from cross to cross for the same character except for number of grains per spike and yield per plant for which the model was inadequate for all three crosses. The two methods were in complete agreement regarding the presence of epistasis in the material. Among the interaction parameters, the component [1] showed the greatest effect for most of the characters in all three crosses where there was evidence of epistasis.
A method of assessing cutaneous pigmentation in bovine skin
Authors: Yang S. H. 
Published: March 2009

1. Since the pigmentation of the skin cannot be assessed by visual examination of the hair or hide, a simple and convenient method of grading the cutaneous pigmentation of cattle based on the microscopic examination of skin sections has been described.2. The degree of cutaneous pigmentation of the skin of twenty body regions of three Ayrshire cows, two Ayrshire bull calves, two Sudanese Zebu bulls, one Sudanese Zebu cow and one Jamaican Zebu cow have been assessed by this method.3. The skin of the Zebu cattle was found to be much more heavily pigmented than that of the Ayrshire cattle.4. The dorsal and lateral regions of both the Zebu and the Ayrshire cattle were more pigmented than the ventral and leg regions.
Phenotypic and genetic associations between production characters and blood characters in sheep. Erythrocyte potassium levels and haemoglobin types in Peppin Merinos genetically different for clean fleece weight and crimp frequency
Authors: Evans J. V. , Moodie E. W. , Burr E. J. , Roberts J. , McGuirk B. J. , Barlow R. 
Published: March 2009

SummaryRed blood cell electrolyte levels and haemoglobin types have been determined in flocks of Peppin Merino sheep genetically different for clean fleece weight and crimp frequency. The flocks selected for high clean fleece weight or low crimp frequency had significantly higher mean erythrocyte potassium levels than did those flocks selected for low clean fleece weight or high crimp frequency, this difference was apparent in both haemoglobin AB and BB types. Erythrocyte potassium concentration was not correlated with either clean fleece weight or crimp frequency within flocks. The high clean fleece weight flock had a significantly higher gene frequency for high potassium than did the low clean fleece weight flock, while the high crimp frequency flock had a lower haemoglobin B gene frequency than the low crimp frequency flock.
Plasma concentrations of glucose and non-esterified fatty acids (N.E.F.A.) in the pregnant and lactating ewe and the effect of dietary restriction
Authors: Patterson D. S. P. , Burns K. N. , Cunningham N. F. , Hebert C. Nancy , Saba N. 
Published: March 2009

1. The effect of undernutrition on the levels of plasma glucose, N.E.F.A. and ketone bodies was observed in fourteen Suffolk-cross ewes late in pregnancy by comparing with data obtained on seven control ewes of comparable pregnancy status. An attempt is made to relate these changes with plasma triglyceride levels, liver fat deposition and plasma pigmentation.2. Evidence is presented which shows that while plasma glucose values are normally distributed, plasma N.E.F.A. levels show a positively skew distribution. This abnormality is corrected by transforming plasma N.E.F.A. values to their logarithms.
Ramularia beticola in sugar-beet seed crops in England
Authors: Byford W. J. 
Published: March 2009

SUMMARYRamularia beticola was prevalent in sugar-beet seed crops in Oxfordshire, Gloucestershire and Lincolnshire in July each year from 1966 to 1971, and defoliated some crops prematurely. It was scarce in Bedfordshire, Huntingdonshire and Essex, and this distribution could not be related to method of growing the crop or density of plant stand. A method is described for assessing leaf spot incidence in beet seed crops after bolting is complete. Fungicide sprays delayed disease development by ca. 2½ weeks.
Studies on feed intake and feed utilization by sheep I. Voluntary feed intake of dry, pregnant and lactating ewes
Authors: Hadjipieris G. , Holmes W. 
Published: March 2009

1. The feed intake of four dry and of twenty pregnant and lactating ewes has been measured. Hay and dried grass cubes alone or in combination were studied on indoor conditions by direct measurement of intake and digestibility while the intake on grazing was measured by the chromic oxide-faecal nitrogen method.2. For dry sheep, hay (61% O.M. digestibility) limited intake to 780 g. D.O.M./day and with added grass cubes there was a steady increase so that intake with cubes alone (although their apparent O.M. digestibility was 56%) was 1140 g. B.O.M./day. Pregnant ewes showed similar intakes and only with ewes carrying twins and triplets was there a slight decline in intake with advancing pregnancy.3. The digestibilities of the diets were similar for pregnant, and lactating ewes.
Digesta flow and mineral absorption in lambs before and after weaning
Authors: Dillon Jane , Scott D. 
Published: March 2009

SummaryFour young lambs fitted with cannulas at the pylorus and at the ileo-caecal junction were used to study the effects of weaning on digesta flow and mineral absorption. Prior to weaning when milk alone was fed the small intestine was the major site for dry matter disappearance and for the absorption of Ca, P, Na and K. Both the small and the large intestine were, however, important sites for Mg absorption at this time.After weaning, when the lambs were fed a concentrate diet, at least two-thirds of the digested dry matter disappeared within the reticulo-rumen. The small intestine, however, still remained the major site for the absorption of Ca, P, Na and K. Most Mg absorption, in contrast, now occurred anterior to the pylorus and it would appear that the move from hindgut to foregut as a site for Mg absorption was directly associated with the introduction of dry feed and the development of fermentative digestion within the reticulo-rumen.Both before and after weaning the faeces was the major route for the excretion of Ca surplus to requirement and the faeces also became increasingly important as a pathway for P and Mg excretion once dry feed was given. The urine, in contrast, was consistently the major pathway for the excretion of Na and K.
Influence of environment and heredity on the shape of lactation curves in Sahiwal cows
Authors: Rao M. K. , Sundaresan D. 
Published: March 2009

SummaryThe shape of the lactation curve of Sahiwal cows was estimated by fitting a gamma function to 2034 lactations made by 681 cows at two farms in Indo-Gangetic plains of Northern India. The persistency of lactation yield was estimated by three methods: P1, the coefficient of variation among weekly yields; P2, ratio of lactation yield to peak yield, and P3, from the gamma function.The gamma function fitted to the weekly yields explained 75·9% of the variation. A least-squares analysis of different traits associated with lactation curve shape indicated significant influence of parity, period and season of calving on the lactation curve. The lactation yield, peak yield and daily yield up to the peak were highest for winter calvers, while persistency was highest for monsoon calvers. The milk yield traits showed an increase up to the second or third lactation, while the persistency decreased from the first to eighth lactation with increase in parity order. The lactation curve was also more flat in the first lactation than later. The lactation yield and persistency increased with increase in age at calving independent of parity order. The lactation yield, peak yield, persistency and daily yield up to the peak were positively correlated with service period, lactation length and calving interval.The heritability and repeatability estimates of different traits, genetic and phenotypic correlations of lactation milk yield with different persistency measures indicated that P2 is a better measure of persistency. The peak yield could be used as a criterion of selection in early lactation to bring about improvement in lactation yield and persistency.
The effect of triamcinolone on glucose metabolism in ketotic sheep
Authors: Ford E. J. H. , Evans Joan 
Published: March 2009

SUMMARYThe withdrawal of food from Clun Forest ewes pregnant with twins produced signs of pregnancy toxaemia accompanied by a significant decrease in the concentration of glucose, a significant increase in the concentration of ketones, non-esterified fatty acids (NEFA) and 3-hydroxybutyrate in plasma and a significant decrease in total entry rate and irreversible loss of glucose. A single intramuscular injection of 0·05 or 0·2 mg/kg of triamcinolone acetonide had no significant effect on the concentration of glucose, ketones or 3-hydroxybutyrate in plasma or on the total entry, irreversible loss or recycling of glucose in ketotic or in normal pregnant sheep. The low dose had a significant effect on the concentration of NEFA in plasma. Recovery from the clinical signs was slow after either dose of steroid but appeared to be hastened by the onset of parturition which was more rapid after the higher dose.
Influence of phosphorus and potassium on forage yields in relation to fertilization and stage of harvest of an oat companion crop
Authors: Hamilton Herman A. 
Published: March 2009

1. The effects on forage yields as a result of the interaction between fertilizer management and stage of harvesting an oat companion crop were studied under the climatic conditions of northern Ontario.2. Grain yields as well as silage yields were increased on the application of 400 lb. 4–24–12 per acre. Fertilization of the corffipanion crop seeded with a- hay mixture resulted in first- and secondyear yields that were significantly greater than those obtained without fertilization of the companion crop.3. By harvesting oats at the silage stage rather than as mature grain only the succeeding firstyear hay yields were significantly greater on the application of additional phosphorus and potassium.
Relating the nitrogen fertilizer needs of winter wheat crops to the soil's mineral nitrogen. Influence of the downward movement of nitrate during winter and spring
Authors: Addiscott T. M. , Darby R. J. 
Published: March 2009

SUMMARYOptimum applications of N fertilizer, Nopt have been related successfully to the amount of mineral N in the soil, Nmin in some parts of Europe but not always in the UK. If there is a body of mineral N, QN, that ultimately lessens the need for N fertilizer, it will not remain constant in its amount or its position. Mineralization will add to QN, while the nitrate component of QN will be leached downwards.Also, part of QN will be taken up into the crop where it will continue to lessen the need for fertilizer N but will be safe from leaching. A computer model was used to simulate these processes for 23 experiments, covering five sites and five years, in which N opt had been estimated. From these simulations we derived trial values of QN that took account of mineral N to a series of depths on a series of dates. For each date we used the trial values to find the depth for which Nopt was best correlated with QN andassumed that this was the depth, dL, of the lower boundary of QN on that date. Thus dL was a collective value for all 23 experiments. The value of dLincreased throughout the winter and the spring and was very closely related to the cumulative average drainage through 0·5 m soil at Rothamsted. By 15 April, dL, was 1·66 m, a depth that was compatible with observations by others that winter wheat can remove mineral N to a depth of at least 1·5 m. We inferred two likely reasons why Nmin may fail as a predictor of Nopt in the UK: insufficient depth of sampling, and too wide a spread of sampling dates. The values of Nopt were shown to be related satisfactorily to the values of QN computed, without any measurements of mineral N, for appropriate depths on single dates.
Effect of cocoa pod ash on the growth of maize
Authors: Adu-Dapaah H. K. , Cobbina J. , Asare E. O. 
Published: March 2009

SUMMARYPot and field experiments were conducted at the Faculty of Agriculture Arable Crops Farm, Kumasi, Ghana during the major rainy season to compare the agronomic efficiency of potassium in cocoa pod ash with that of muriate of potash and to determine the optimum rate of application of cocoa pod ash to maize (Zea mays L. cv. La Posta). Results from the two experiments indicated that the application of 90 kg N/ha and 67 kg P2 O5/ha did not increase shoot dry matter (DM) yield over the control. However, significant increases in DM yield over the control were obtained when N and P were applied together with 56 kg K2O/ha, demonstrating the complementarity of the major nutrient elements N, P and K. Shoot and root DM increased with increasing application of cocoa pod ash. Application of 140 kg/ha cocoa pod as (equivalent to 56 kg K2O/ha) produced the same DM and shoot potassium yields as 56 kg K2O/ha as muriate of potash. The optimum rate of application of cocoa pod ash was 280 kg/ha (112 kg K2O/ha).
Natural sucking performance and age of weaning in zebu cattle (Bos indicus)
Authors: Reinhardt V. , Reinhardt Annie 
Published: March 2009

SUMMARYSucking behaviour and age of weaning were investigated in a herd of East African zebu cattle in which all calves born had been retained for several years. Suckling rates were compared at different periods of the 24 h cycle and found to be less at night than during any day-time period. The highest rates of suckling took place in the early morning and in the late afternoon. The early morning suckling was triggered by the dawn. During both night and day, suckling was irregular and bouts were presumably due to sympathetic induction because a high proportion of the calves was suckled on each occasion. The total sucking time and the number of bouts varied significantly in inverse relation to age of the calf but the duration of a sucking bout was constant at 8 min and independent of age. There was an average of 4·8 sucking bouts within 24 h giving a total duration of 38 min. Sucking behaviour did not exhibit sex-specific differences. The average age of natural weaning was 10 months but there was a marked sex difference. Female calves were prevented by their mothers from sucking after an average age of 8·8 months but male calves continued to be suckled for a further 2·5 months and were weaned at an average age of 11·3 months.
Effect of leaf position and plant age on the translocation of 14C-assimilates in onion
Authors: Khan A. A. 
Published: March 2009

SUMMARYIndividual leaf blades of onion plants were treated with 14CO2 57, 71, 93 and 112 days after transplanting. The distribution of labelled translocates was determined 24 h after labelling. The older the plant the more of 14C-assimilate left the source leaf; 112 days after transplanting, leaves 1–7 all exported more than 70% with leaf 7 showing a maximum export of 93 % of the fixed carbon. In the early stages of the development, the leaves, pseudostem and the bulbs were the major sinks in decreasing order. But the bulbs became the dominant sink at 71 days and at 112 days the bulbs almost monopolized the import of the radiocarbon, with 90 % of the exported 14carbon being recovered from them. The bulbs received their 14carbon supply from all the leaves but particularly the basal and middle region leaves. Roots were a weak sink and received their 14carbon supply only from basal leaves. The stem and mature leaf blades were unimportant sinks throughout the life of the plant.
Controlled environment composting for mushroom cultivation: substrates based on wheat and barley straw and deep litter poultry manure
Authors: Noble R. , Gaze R. H. 
Published: March 2009

SummarySubstrates for mushroom cultivation were prepared, following a 2 day mixing and blending process, in bulk tunnels under a controlled temperature regime using forced ventilation. The temperature regime was based on a conventional bulk tunnel composting process, i.e. pasteurization at 60 °C for 6 h, followed by a conditioning phase at 47 °C until the substrate was clear of ammonia. With the exception of ammonia, which increased with increasing compost nitrogen content, this process did not result in strong odours. The substrates were ready for inoculation with mushroom ‘spawn’ 7–12 days after the initial mixing of the compost ingredients. Increasing the compost nitrogen content from 1·1 to 2·5% of the dry matter by increasing the quantity of deep litter poultry manure added to straw in the ingredients resulted in a greater subsequent yield of mushrooms. Further increases in the substrate nitrogen content resulted in prolonged tunnel processing times, substrate desiccation, incomplete clearance of ammonia from the substrate and subsequently low or no mushroom yields. Substrate bulk density at the time of spawning decreased with increasing nitrogen content, but was increased by chopping the straw ingredient. Mushroom yields from composts prepared with barley straw were significantly lower than those from wheat straw composts, at equivalent nitrogen contents. Supplementation of prepared substrates with the proprietary protein-rich ingredient, Betamyl 1000, increased yields by 13·6%.
Effects of condensed tannins inLotus pedunculatuson its nutritive value for sheep. 2. Nitrogenous aspects
Authors: Waghorn G. C. , Shelton I. D. , McNabb W. C. , McCutcheon S. N. 
Published: March 2009

SummaryFourteen young wether sheep were fed freshly cutLotus pedunculatusas a sole diet to examine the effects of condensed tannins (CT; 55 g/kg lotus DM) on nitrogenous aspects of digestion. The experiment was carried out indoors at Palmerston North, New Zealand over 32 days with one group of sheep receiving an intraruminal infusion of polyethylene glycol (PEG; 100 g/day) to preferentially bind CT (PEG group) so that the lotus was essentially ‘CT-free'. The other sheep, not given PEG, were termed the ‘Tannin’ group.The principal effects of CT were to increase the flow of feed nitrogen (N) to the abomasum despite a 12% reduction in DM intake of the Tannin sheep. Rumen microbial N turnover rate was slower in Tannin animals than in those receiving PEG (1·86v. 2·63/day) but microbial N flux to the abomasum was similar in both treatments. The proportion of N intake disappearing from the rumen was lower in Tannin (0·13) than in PEG sheep (0·26) and the N digestibility was 0·67 and 0·81 for the respective treatments (P <0·001).The beneficial effects of CT in reducing rumen degradation of feed protein were negated in part by a reduction in fractional absorption of amino acids (AA) from the small intestine. Fractional absorption of essential AA was 0·66 in Tannin and 0·79 in PEG sheep; values for non-essential AA were 0'59 in Tannin and 0·73 in PEG groups. Amino acid concentrations in blood were similar for both groups, but Tannin sheep had lower plasma urea concentrations, a more rapid plasma urea turnover rate and a higher irreversible loss than those receiving PEG. Growth hormone concentrations in plasma were similar for both treatments.
Soil-plant nitrogen dynamics following incorporation of a mature rye cover crop in a lettuce production system
Authors: Wyland L. J. , Jackson L. E. , Schulbach K. F. 
Published: March 2009

SUMMARYWinter non-leguminous cover crops are included in crop rotations to decrease nitrate (NO3-N) leaching and increase soil organic matter. This study examined the effect of incorporating a mature cover crop on subsequent N transformations. A field trial containing a winter cover crop of Merced rye and a fallow control was established in December 1991 in Salinas, California. The rye was grown for 16 weeks, so that plants had headed and were senescing, resulting in residue which was difficult to incorporate and slow to decompose. Frequent sampling of the surface soil (0–15 cm) showed that net mineralizable N (anaerobic incubation) rapidly increased, then decreased shortly after tillage in both treatments, but that sustained increases in net mineralizable N and microbial biomass N in the cover-cropped soils did not occur until after irrigation, 20 days after incorporation. Soil NO3-N was significantly reduced compared to winter-fallow soil at that time. A15N experiment examined the fate of N fertilizer, applied in cylinders at a rate of 12 kg15N/ha at lettuce planting, and measured in the soil, microbial biomass and lettuce plants after 32 days. In the cover-cropped soil, 59% of the15N was recovered in the microbial biomass, compared to 21% in the winter-bare soil. The dry weight, total N and15N content of the lettuce in the cover-cropped cylinders were significantly lower; 28 v. 39% of applied15N was recovered in the lettuce in the cover-cropped and winter-bare soils, respectively. At harvest, the N content of the lettuce in the cover-cropped soil remained lower, and microbial biomass N was higher than in winter-bare soils. These data indicate that delayed cover crop incorporation resulted in net microbial immobilization which extended into the period of high crop demand and reduced N availability to the crop.
Growth, morphology and nutritive quality of shaded Stenotaphrum secundatum, Axonopus compressus and Pennisetum clandestinum
Authors: Samarakoon S. P. , Wilson J. R. , Shelton H. M. 
Published: March 2009

SUMMARYThe response to shade in growth and nutritive quality of buffalo grass (Stenotaphrum secundatum) was compared with that of two other stoloniferous grasses, mat grass (Axonopus compressus) and kikuyu grass (Pennisetum clandestinum). The grasses were grown outdoors in Brisbane, Australia, in soil in pots over two growing seasons in 1985/86. Treatments in the first season (Expt 1) were shading at 0 (full sun), 42, 59 and 68% with moderate N (two spaced applications of 50 kg/ha) and, in the second season (Expt 2), 0 and 59% shade with high (50 kg/ha every 2 weeks) and low (5 kg/ha every 2 weeks) N.Unusually for tropical grasses, the top yield of all species was higher under shade than in full sun, except for S. secundatum at high N in Expt 2. S. secundatum and A. compressusshowed an increase in top yield up to 68% shading whereas P. clandestinum reached a maximum at 42% shading. Shade increased shoot:root ratio and specific leaf area in all species but had little effect on leaf:stem ratio and the proportion of dead material in the tops. Stubble yield (stem bases and stolons) was reduced under shade but to a much smaller extent than root yield. S. secundatum and A. compressus had similar morphological characteristics. Their yield was lower than that of P. clandestinum in Expt 1 (autumn growth) but was similar to that of P. clandestinum in Expt 2 (summer growth). These grasses had a higher leaf:stem ratio and lower proportion of dead material in tops than P. clandestinum.Shade generally increased herbage nutritive value through an increase in N concentration and drymatter digestibility. The latter response was somewhat variable and mostly small (1–3% units). Under shade, the general trend was towards a decrease in total nonstructural carbohydrates, cell-wall content and insoluble ash, and an increase in lignin content. A. compressus was higher in digestibility and soluble carbohydrates than the other grasses.S. secundatum was not clearly superior in response to shade and its nutritive quality was lower than that of A. compressus.