bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the efficiency of mating in the sheep II. The effect of freedom of rams, paddock size, and age of ewes
Authors: Lindsay D. R. , Robinson T. J. 
Published: March 2009

A factorial experiment is described in which thirty-six aged and thirty-six maiden spayed crossbred ewes were used in four successive tests at intervals of 15 days in a study of factors affecting the detection of oestrus. Variates introduced into each test were: (a) freedom of rams (free or tethered); (b) size of mating paddock (17 acres or ⅕ acre); (c) age of ewe (maiden or aged); and (d) dose of oestrogen (oestradiol benzoate, ODB: 10·0, 15·6, 24·4 μg.).All ewes were primed with progesterone for 12 days prior to ODB injection and joining. The number of ewes detected in oestrus and the number and identity of rams which served each ewe were recorded.In the four successive tests 29, 33, 36 and 30 ewes were served.Significant main effects were: (a) freedom of rams—free 77, tethered, 51 (P < 0·001); (b) size of mating paddock—17 acres 49, ⅕ acre 79 (P < 0·001); (c) age of ewes—aged 57, maiden 71 (P < 0·05); and (d) dose of ODB—10·0 μg., 20; 15·6 μg., 41; 24·4 μg., 67 (P < 0·001).Significant interactions were: (a) test number × age (P = 0·01), and (b) test number × dose of ODB (P < 0·05). The number of maiden ewes served increased and that of aged ewes decreased withsuccessive tests. There was a barely significant ohange in the slope of the ODB D/R line.Ewes showed no obvious preference for tethered rams of any particular breed. There was a positive correlation between the performance of rams when free and tethered.
Some carcass characteristics of commercial quality cattle in Mexico
Authors: Butterworth M. H. , García E. , Aguirre E. L. 
Published: March 2009

SUMMARYLittle is known about the carcass characteristics of unimproved commercial (or ‘Criollo’) cattle although these still account for a large proportion of slaughter animals in Latin America.Data were collected from 52 commercial cattle in a commercial slaughterhouse in Monterrey, N.L. Mexico. They included carcass weight, length, total edible meat (carcass fat was negligible), total bone and eleven typical Mexican cuts whose anatomical relations are described. The age of the animals was judged according to dentition and data were stratified using this criterion for analysis. Variations in total edible meat, which averaged 77·4%, were almost entirely accounted for by differences in body weight. Data are presented to indicate amounts of various cuts in the carcasses and some significant differences were demonstrated in values for these cuts among age groups; possible explanations for this were discussed. Prediction equations were calculated to relate total edible meat with the selected cuts and carcass weight and it was found that carcass weight gave the best prediction of total edible meat and could also be used to predict expected weights of individual joints with reasonable accuracy.
Some effects of seed size and spacing on the yield and grading of two maincrop potato varieties: I. Final yield and its relationship to plant population
Authors: Wurr D. C. E. 
Published: March 2009

SUMMARYTwo experiments, which investigated the effect of three seed sizes and three withinrow spacings on the graded yield of the two early maincrop varieties Pentland Crown and Maris Piper, are described and the results discussed.Relationships were established between yields in various grades and stem population, and are used to explain the response of yield to changes in seed size and spacing. Comparisons between any two levels of the same treatment were affected by the size grade in which they were made. In addition, the tendency towards interactions between variety and seed size and between variety and spacing suggests that comparisons between varieties are affected by the populations at which these comparisons are made.
The metabolism of glucose, acetate, lipids and amino acids in lactating dairy cows
Authors: Bickerstaffe R. , Annison E. F. , Linzell J. L. 
Published: March 2009

SUMMARYSpecialized techniques, previously used in surgically prepared goats, which simultaneously measure udder metabolism (arteriovenous difference of milk precursors x udder blood flow) and the whole body turnover of the milk precursors, have been successfully transferred to dairy cows. Methods of obtaining representative samples of arterial and mammary venous blood and of measuring udder blood flow are described.The rates of entry into the circulation, as determined by isotope dilution, of glucose, acetate and plasma free fatty acids were 3·3–4·0, 1·7–2·1 and 0·5 kg/day respectively. Acetate and glucose contributed 32–50 and 4–11% respectively of the total CO2output by the animal.Measurement of the uptake of precursors of milk constituents and their transfer into milk showed that there were substantial arteriovenous differences of glucose, acetate, triglyceride and β-hydroxybutyrate which were not significantly different between breeds or related to milk yield. Isotopic and balance data confirm that glucose is the main precursor of lactose and that the oxidation and transfer of glucose into lactose accounted for 69–98% of the glucose entry rate. As in the goat, plasma triglycerides and blood acetate accounted for 35–80% and 25–50% of the milk triglycerides respectively. Propionate was extracted from plasma but the uptake was only about 8% of the value for acetate.There was no net arteriovenous difference of phospholipids, cholesterol esters or free fatty acids, but the fall in specific radioactivity of free fatty acids across the mammary gland indicated there was an exchange of free fatty acids between plasma and mammary tissue. In agreement with previous findings, acetate contributed to all the milk fatty acids up to a chain length of C14and part of the C16fatty acid. Plasma triglycerides contributed to the remainder of the C16 fatty acid and all the milk fatty acids with a chain length of C18or higher.In contrast to the lactating goat, cow plasma contained very few chylomicrons. The majority of the triglycerides taken up by the udder were derived from the lowdensity lipoprotein fraction.The essential amino acids were extracted from blood in amounts sufficient to account for the essential amino acids secreted into milk protein. Although the plasma level of methionine was low, 52–72% of the material reaching the mammary gland was taken up. The uptake of arginine was far in excess of the requirement for milk protein synthesis.
The effect of certain seed treatments on dormancy and emergence in groundnuts
Authors: Nur I. M. , Gasim A. A. E. 
Published: March 2009

SUMMARYTwo experiments were made in each of the seasons 1971/72 and 1972/73 to determine the effect of seed treatment on groundnut emergence.In one of the experiments, groundnut seed germinated at a faster rate when the seed was dressed with Aldrex T at 2·2 g/kg of seed.In the other experiment, no difference in emergence was found between varieties whether planting was on the same day as shelling or 12 weeks after shelling.
The effect of winter and spring sowing on the grain composition of oat varieties
Authors: Welch R. W. 
Published: March 2009

SUMMARYSix spring varieties of oats were sown in a glasshouse in winter and in spring. The grain was analysed for oil, protein and kernel content and 1000-grain weight, and the maturation period was measured.Oil content varied from 2·4 to 7·9% and protein content from 7·9 to 16·3%. Varietal differences in oil content between varieties were recognized and these were maintained at both sowing dates.Winter sowing, in comparison with spring sowing, resulted in an increase in oil and kernel content and 1000-grain weight, and a decrease in protein content. The increased oil content was partly due to increased kernel content, while the decrease in protein content was partly due to changes in 1000-grain weight.The maturation period was not affected by sowing date, but was positively correlated with oil content. Oil and protein content were not negatively correlated, and there were indications that it may be possible to select varieties which will produce grain high in both oil and protein.
The ‘teat order’ of suckling pigs: II. Fighting during suckling and the effects of clipping the eye teeth
Authors: Fraser D. 
Published: March 2009

SUMMARYThe development of stable suckling order, the incidence of fighting when suckling, weight gain during the suckling period, and the severity of facial wounding were studied with litters of piglets in which the canine and lateral incisor teeth were either clipped at birth or left intact. Facial wounding was largely confined to litters with unclipped teeth. Severity of wounding correlated with the observed incidence of fighting on the udder (P<0·01); and both wounding and fighting were more common among litters comprising a large number of piglets (P<0·05). When the effect of litter size was taken into account, there were no substantial differences in weight gain to 3 weeks between piglets with high and low scores for facial wounding, nor between clipped and unclipped litters. Piglets which habitually occupied the most anterior or most posterior teats had less facial wounding than middle-suckling piglets, and showed greater consistency in teat choice. No gross differences between clipped and unclipped litters were observed in the development of stable suckling order during the first week of life. It is concluded that the ‘eye’ teeth, although used in disputes over teat choice, have little influence on the frequency of such disputes or on the original development of stable suckling order.
Response of cotton to water and nitrogen in a tropical environment: II. Date of last watering and rate of application of nitrogen fertilizer
Authors: Hearn A. B. 
Published: March 2009

SUMMARYFour rates of nitrogen fertilizer, three dates for the last application of water, and two varieties were combined factorially in two experiments in successive years. Leaf water potential was measured. There were large yield responses to water and nitrogen; in both cases the response in number of bolls was relatively twice as great as that in boll weight. Because one effect of nitrogen was to prolong the setting of bolls, which required continued watering for its full expression, there was an interaction between the nitrogen and water treatments which affected number of bolls, and thus yield. Deltapine 16 yielded more than Acala 1517BRI and responded more to nitrogen than did Acala 1517BRI. Heavy nitrogen rates decreased the initial rates of boll setting of Acala. Weekly picks of open bolls showed that, with early cessation of water and with the lightest rate of nitrogen, the boll weight decreased in the fourth and subsequent picks. This effect of nitrogen was more marked in Acala. These responses were analysed into the components of boll weight and are discussed in relation to the timing of the development of the bolls in order to explore the physiological implications. Nitrogen and water delayed harvest by prolonging effective flowering, by increasing boll maturation period, and by increasing the number of defoliant sprays required.
A note on the effect of genotype, density and row width on the yield and quality of forage maize
Authors: Phipps R. H. 
Published: March 2009

SUMMARYThe results are presented from a factorial experiment on the effects of genotype (Julia, Inra 200 and Caldera 535), density (4·9, 11·0 and 16·7 plants/m2) and row width (70 and 35 cm) on the quantity and quality of maize produced 136 days after emergence.The later maturing the variety, the higher was the dry matter yield, but the lower was the dry matter percentage. There was little advantage in favour of the high density when compared with the medium density, while row width did not markedly affect the production character measured. Both density and variety significantly influenced the ripe ear. The dried grain/ear for the low, medium and high densities was 111, 89 and 74 g respectively. However, at the highest density nitrogen content, dry matter digestibility and digestible organic matter in the dry matter were all slightly reduced. With the exception of magnesium, the mineral contents showed similar trends.
Studies on the Carbon and nitrogen cycles in the Soil. IV. Natural and artificial humic acids
Authors: Toit M. M. S. Du , Page H. J. 
Published: March 2009

The preparation of natural humic acids from soil, peat (Dopplerite) and “Adco,” and of artificial “humic” acids from sucrose, cellulose, dextrose and glycine (Maillard), furfural, hydroquinone and lignin, and their purification is described.Their elementary composition and their behaviour under conductometric titration with ammonia have been studied. The artificial products from sucrose and furfural did not behave as acids, but all the natural products, and the artificial products from cellulose, hydroquinone and lignin possessed the properties of colloidal acids.Preliminary investigations into the “humification” of furfural and ω-hydroxymethyl furfural, and into the interaction of dextrose with amino bodies, are described.
The effect of dietary energy concentration on protein utilization during late pregnancy in ewes
Authors: Guada J. A. , Robinson J. J. , Fraser C. 
Published: March 2009

SUMMARYFrom 62 days of gestation to parturition, 20 Finnish Landrace x Dorset Horn ewes were each offered one of four diets with roughage to concentrate ratios of 20:80; 40:60; 60:40 and 80:20, at daily metabolizable energy and digestible crude protein intakes of 490 kJ and 3·55 g/kg W0·75respectively. Plasma concentration of free fatty acids, glucose and urea were determined weekly, and nitrogen balance and digestibility trials were carried out at 70–80 and 130–140 days of gestation.On all treatments the concentration of plasma free fatty acids increased during pregnancy from approximately 200–600 μ-equiv./l and the concentration of glucose and urea decreased by approximately 25%.Digestibility coefficients for dry matter and organic matter increased from 58 to 68% and from 60 to 70% respectively as the proportion of concentrates in the diet increased and were not affected by stage of gestation. The apparent digestibility of nitrogen was not affected by the energy concentration of the diet.Between mid and late gestation there was a mean increase in daily nitrogen retention of 2·5 g and an improvement in the efficiency of nitrogen utilization of 19 percentage units.Nitrogen retention and the efficiency with which the apparently digested nitrogen intake was retained increased as the dietary energy concentration was increased. The mean daily increases in nitrogen retention were 0·0135 and 0·0039 g for each percentage unit increase in the concentrate portion of the diet at mid and late gestation respectively. The corresponding values for the improvement in the efficiency of nitrogen utilization were 0·13 and 0·10%.
Nitrogen, phosphorus and potassium fertilizers for potatoes in Cyprus
Authors: Krentos V. D. , Orphanos P. I. 
Published: March 2009

SUMMARYA number of experiments to test the effects of N and P fertilizers and a few testing K fertilizer were carried out mainly with Arran Banner and Up-to-Date potatoes in the major potato-growing area of Cyprus (Kokkinoohoria). The optimum nitrogen rate, all applied at planting in January-February, was 60–120 kg N/ha with yields reaching 50 t/ha. Phosphorus increased yields in only 4 out of 21 trials. In two of these cases the soil contained 8 mg bicarbonate-extractable P/kg soil or less. In the other two cases the soil contained 34 and 56 mg P/kg but irrigation was erratic. In only one experiment where soil potassium was depleted to 222 mg exchangeable K/kg through continuous cropping with irrigated crops, without potassium fertilizer, was a clear response to K fertilizer obtained; this, however, is the first response to K fertilizer by any crop reported in a plain area of Cyprus.Concentration of NO2·N in the petiole of the first mature leaf from the top sampled at 80 days from planting under the 120 kg N/ha rate, beyond which seldom were yields increased, was about 0·5%. In the only experiment where a response to K was obtained, concentration of K in entire leaves sampled as above was about 2·5%.It is argued that since growers in this area have used heavy dressings of P and K over recent years, they will seldom get any benefit from applying more than a maintenance dose of 70 kg P and 150 kg K/ha to the potato crop. It is suggested that since in semiarid regions leaching is limited, soil tests of NO3content can aid farmers in choosing the optimum amount of N fertilizer for each crop.
The engulfment and digestion of mixed rumen bacteria and individual bacterial species by single and mixed species of rumen ciliate protozoa grownin vivo
Authors: Coleman G. S. , Sandford Deborah C. 
Published: March 2009

SUMMARYFive species of rumen ciliate protozoa, isolated from sheep in which they were the only ciliate protozoon, and mixed rumen ciliates were incubated with labelled bacteria and the rate of uptake and digestion of the bacteria was followed. Evidence is presented that mixed rumen bacteria labelled by incubation with14C-isoleucine,14C-guanine or35S-sulphate were engulfed more rapidly by the protozoa than those labelled with14C-glucose but that, withEntodiniumspp. at least, this apparent lower rate of uptake was associated with an increased rate of digestion. The rate of uptake of mixed rumen bacteria (at 109/ml) varied from 230 to 2670 bacteria/protozoon per hour, depending on the protozoal species, and increased with increasing bacterial population density. Starvation of the protozoa decreased the initial rate of uptake of bacteria by up to 60% and the length of time over which the protozoa would engulf bacteria.Entodiniumspp. andEpidinium ecaudatum caudatumengulfed fewer bacteria when these bacteria were prepared from the same sheep as the protozoa than when they were prepared from sheep with no or other protozoal populations. Of the protozoa tested, onlyEntodiniumspp. and the mixed large rumen protozoa digested mixed rumen bacteria,Eremoplastron bovisandEpidinium ecaudatum caudatumbeing inactive. It is suggested that previous estimates of the rate of uptake and digestion of bacteria based on studiesin vitrowere too high.The non-rumen bacteriaEschericfoia coliandKlebsiella aerogenesand the rumen bacteriumMegasphaera elsdeniiwere not or only poorly taken up by the protozoa.Entodiniumspp. selectively engulfed bacteria of rumen origin and digested two cellulolytic bacteria rapidly. In contrast,Eremplastron bovisengulfed these cellulolytio bacteria more slowly than other bacteria.Entodiniumspp. and the large rumen protozoa digested more bacterial species than the other protozoa butButyrivibrio fibrisolvenswas digested more rapidly than other bacteria by all the protozoa.
Inverse relationship between concentration of progesterone and nutrition in ewes
Authors: Williams A. H. , Cumming I. A. 
Published: March 2009

SUMMARYMean progesterone concentrations were measured in the peripheral plasmas of Merino and Border Leicester × Merino ewes which were fed from day 2 to day 16 after mating on rations designed to provide twice maintenance (2 M), maintenance (M) and one quarter maintenance (¼ M) of food requirements. Mean plasma progesterone concentrations were consistently higher in the ¼ ewes than in the M or 2 M ewes whether they had two corpora lutea (CL) and two embryos surviving or one CL with either one embryo surviving or no embryo surviving, and tended to be lower in the 2 M than M ewes. It is concluded that there is an inverse relationship between levels of nutrition and progesterone within an oestrous cycle in ewes.
The effect of maleic hydrazide and chlorocholine chloride on the growth, seed yield components and seed yield of S.23 ryegrass
Authors: Hebblethwaite P. D. , Burbidge A. 
Published: March 2009

SummaryThe effects of maleic hydrazide (MH) and chlorocholine chloride (CCC) on S. 23 perennial ryegrass grown for seed were investigated in a series of field experiments from 1972 to 1974. MH significantly decreased straw length and lodging, but also decreased all yield components, seed yield and germination percentage. All growth stages and harvest date were delayed and the seed production mechanism impaired. CCC had little effect on length of fertile tillers or lodging but seed yield was increased in 1972 and 1973 when the chemical was applied at spikelet initiation. In 1972 an increase in 1000-grain weight and in 1973 small but insignificant increases in numbers of fertile tillers and seeds per spikelet were responsible. This chemical had no visible effects on the growth and development of the crop or on germination percentage of the seed.
Breeding for protein percentage and seed weight in Phaseolus vulgaris L.
Authors: Polignano G. B. 
Published: March 2009

SUMMARYThree successive generations (parents, F1, F2) and backcrosses of the common bean (Phaseolus vulgaris L.) hybrid between the cultivars Swedish Brown and Seafarer were used in this study.The investigation has concentrated on assessing the relationship between the seed weight per plant and the protein percentage of the seed. Protein percentage showed a higher estimated heritability and a greater stability over environments than seed weight.Partial dominance for low percentage protein and low seed weight was noted. Negative and low regression coefficients between these two characters was also observed.SDS-gel electrophoresis was used to examine the variation in banding patterns of total seed polypeptides and their stability over environments.
The effect of sowing date, seed rate and nitrogen fertilizer on the growth and yield of Isbagol (Plantago ovata F)
Authors: Randhawa G. S. , Sahota T. S. , Bains D. S. , Mahajan V. P. 
Published: March 2009

SummaryAn experiment to study the effect of sowing time (21 October, 5 November, 20 November, 5 December and 20 December), seed rate (5, 7·5 and 10 kg/ha) and application of nitrogen fertilizer (0, 20, 40 and 60 kg N/ha) was conducted at the Punjab Agricultural University, Ludhiana, on a loamy sand soil during the winter seasons of 1974–5 and 1975–6. The delay in sowing from 21 October to 20 December produced shorter plants with fewer spikes. The crop sown on 21 October using 7·5 or 10 kg seed/ha and supplied with 20 or 40 kg N/ha gave better yield than those of later sowings.