bluuebunny/crossref_metadata_2025 huggingface dataset:
A technique for determining the proportion of C3 and C4 species in plant samples using stable natural isotope's of carbon
Authors: Ludlow M. M. , Troughton J. H. , Jones R. J.
Published: March 2009

A technique is described which uses the ratio of the natural 12C and 13C isotopes of carbon to calculate the proportions of Calvin pathway (or C3) species and C4 dicarboxylic acid pathway (or C4) species in mixed samples of shoots, roots or seeds. Mean percentage of a particular component can be predicted to within ± 2% of actual values with average standard errors of less than 1% with two component mixtures under good conditions using threefold replication. The technique is particularly useful for estimating the proportion of C3 and C4 species in samples of visually indistinguishable, intermingled root systems from mixed field communities or from competition experiments. The proportion of C3 and C4 species in both oesophageal fistula and feed samples can be obtained using this technique, and it is proposed that data from fistula and pasture samples could be used to determine the extent to which animals selectively eat C3 or C4 species. The advantages and disadvantages of the technique are discussed.
The digestion of untreated and formaldehyde-treated soya-bean and rapeseed meals by cattle fed a basal silage diet
Authors: Rooke J. A. , Brookes I. M. , Armstrong D. G.
Published: March 2009

The effect of pretreating soya-bean and rapeseed meals with formaldehyde was studied. Soya-bean and rapeseed meals, both untreated and formaldehyde-treated, were fed to cattle receiving a basal diet of silage in a 4 × 4 latin square. Formaldehyde treatment of both meals significantly reduced apparent N digestibility. All four protein supplements increased the amounts of non-ammonia N and amino acid N entering the small intestine over those obtained when silage was fed alone. Formaldehyde treatment of the meals increased the amounts of non-ammonia N and amino acid N entering the small intestine; this effect was significant, however, for only the formaldehyde treatment of the soya-bean meal. The low efficiency of microbial N synthesis observed when silage was fed alone was increased by the inclusion of both of the soyabean meals in the diet but not by the inclusion of the rapeseed meals. Formaldehyde treatment reduced the apparent degradability of the soya-bean meal N, determined in vivo, from 0·90 for the untreated meal to 0·40 for the formaldehyde-treated meal; similarly the degradability of the untreated rapeseed meal was reduced from 0·77 to 0·41 by the formaldehyde treatment. The in sacco technique gave values for degradability for the protein supplements which ranked them in a similar manner as did the in vivo technique; however, for any one meal the in sacco value for degradability was lower than that determined in vivo.
A comparison of two methods of NaOH treatment of spring barley straw with untreated straw and hay
Authors: Smith T. , Siviter J. W. , Broster W. H.
Published: March 2009

Spring barley straw treated with NaOH, either chopped and ensiled or ground and pelleted, was compared with long untreated straw and hay, in mixed diets of compound and forage fed to yearling dairy heifers. Protein allowance and source were varied by the inclusion of either fishmeal, soya-bean meal or urea in the diet.

Growth rate was improved in two out of three trials by chopped ensiled straw treated with NaOH, compared with long untreated straw, and equalled that supported by hay. Dry-matter intake and digestibility were also improved, although rumen NH3-N concentrations were low. With ground pelleted straw treated with NaOH the effects were less decisive: growth rate was increased once and reduced once compared with long untreated straw, but dry-matter intake was substantially increased. Digestibility remained similar to that of long untreated straw, and was unchanged by rate of feeding. NaOH treatment resulted in small changes in molar proportions of VFA. Digestibility of hay fell when concentrates were added to the diet.

Fishmeal increased growth rate with all forms of straw and hay and was more efficient in this respect than either soya-bean meal or urea.
The effects of dietary phosphorus inadequacy during pregnancy and lactation on the voluntary intake and digestibility of oat straw by beef cows and the performance of their calves
Authors: Fishwick G. , Fraser J. , Hemingway R. G. , Parkins J. J. , Ritchie N. S.
Published: March 2009

Two groups of nine in-calf beef cows were given daily for the last 16 weeks of pregnancy and the first 6 weeks of lactation 1·35 increasing to 3·15 kg molassed sugarbeet pulp dry matter containing added urea together with oat strawad libitum. Additionally, one group of cows received supplementary dicalcium phosphate which increased their total phosphorus intake from about 12 to 28 g P/day.

In the absence of phosphorus supplementation, there was a marked and significant reduction in the concentration of phosphorus in the blood, and by the 4th week of lactation this was reflected in a decrease in radiographic density of the tail bones but not in a depletion of rib bone ash.

During pregnancy a severely reduced phosphorus intake did not reduce either calf birth weight or the digestibility and voluntary intake of straw. An inadequate phosphorus intake during lactation resulted in a significant decline in voluntary straw consumption and digestibility. There was an accompanying decrease in metabolizable energy intake from about 78 to 55 MJ/day, an increased weight loss in the cows and a depression in their milk yield such as to significantly reduce calf live-weight gain.

The long period of phosphorus inadequacy did not affect the subsequent satisfactory reproductive performance of the cows when both groups were transferred to grass and mated with a bull.
The germination of excreted kikuyu grass seed in cattle dung pats
Authors: Wilson G. P. M. , Hennessy D. W.
Published: March 2009

The quantity of seed ingested and excreted by penned cattle from offerings of freshly cut kikuyu grass (Pennisetum clandestinum cv. Whittet) was measured during the autumn at Grafton, N.S.W. A mean 101·6 g of whole seed was ingested per head per day, of which 22·9% was excreted. During 18 weeks, seedlings emerged from every dung pat formed from collected faeces. The number of seedlings represented 3·45% of the whole seed ingested. The loss of covering structures from the seed during passage through the alimentary tract apparently reduced the 21–day germinability.
Follicle population in Black Bengal goats
Authors: Khan M. A. Bari , Talukdar A. H.
Published: March 2009

Many authors have studied the follicle population in sheep and goats with a view to establishing a scientific basis for the breeding of sheep and goats with improved wool.

Pant & Kapri (1966) examined skin samples from five Gaddis, ten Angoras seven F1S, eight first back crosses to Angora, four second back crosses to Angora and eight goats produced by inter se mating of the second back crosses and recorded the S/P ratio as 0·019, 6·55, 5·58, 6·25, 8·30 and 6·78 in the six types respectively. Das, Mitra & Nayudamma (1963) mentioned that the percentage of coarse hairs was about 35 in Indian goats. According to CLRI (1963) the density of hairs in Calcutta Black Bengal goats varies between 9000 and 13000/in.2 of the skin surface area and coarse hairs constituted about 28% of the total hairs. Ryder (1966) mentioned that the S/P ratio in Australian goats ranged from less than 5/1 to 7/1. He also noted the S/P value in Scottish goats as 3/1–5/1 and that in female Toggen-burg goats as 2·5/1–3·9/1. Sar & Calhoun (1966) reported that in Common American goats, three to six secondary follicles were associated with the trio of primary hair follicles. According to Burns (1965) the S/P ratio of Nigerian goats was 4/1. Margolena (1966) reported that in Texas and South African Angora does the primary follicles comprised about 9–14% of the total number of follicles. The purpose of this present investigation is to provide basic information on the S/P follicle ratio in Bangladesh Black Bengal goats.
Studies in grazing management. VII. The influence of strip grazing versus controlled free grazing on milk yield, milk composition, and pasture utilization
Authors: Arnold G. W. , Holmes W.
Published: March 2009

1. Experiments were carried out in 1956 and 1957 in which milking cows were grazed at the same stocking rate, either on strip grazing or on free grazing. The cows followed balanced Latin Square designs.

2. The pastures were liberally fertilized, either with NPK fertilizer (202 lb. N, 202 lb. P2O5, 252 lb. K2O per acre in 1956 and 80% of these quantities in 1957), or with PK fertilizers (269 lb. P2O5 and 269 lb. K2O in 1956 and 80% of these quantities in 1957), and a subsidiary comparison of the effect of nitrogenous fertilizers was made in 1956.

3. At the end of the main experiment in 1956 a study of the effect of straw offered to the grazing cows was made. No supplement other than straw was offered.

4. The results in both years showed no difference in milk yield per cow due to treatments, nor in 1956 was milk yield or milk composition affected by grazing treatment, fertilizer treatment or the provision of straw.

5. In both years the live-weight gain per cow was less with free grazing. In 1956 the provision of straw increased the rate of live-weight gain. It is suggested that these differences are mainly due to gut fill.
Further studies of the rate of passage of food through the alimentary tract of pigs
Authors: Castle Elizabeth J. , Castle M. E.
Published: March 2009

1. Four replicated experiments were made to determine the rate of passage of meal through the alimentary tract of pigs on different feeding treatments. In each experiment stained meal was used and the results were expressed by means of excretion curves. From these, mean retention times (R values) were calculated. All the curves were of a similar sigmoid shape.

2. A significant inverse relationship was found between the mean retention time and the total weight (meal plus water) of the ration. This relationship was found when (a) the weight of meal was constant and the weight of water was varied, (b) the weight of water was constant and the weight of meal was varied, and (c) the total combined weight of meal and water (at the same ratio) was varied.

3. The digestibility of the dry matter and crudec protein in Exps. 1–3 was not altered greatly as a result of the different feeding treatments.

4. In Exp. 4, similar rates of passage were found in pigs fed on the two rations of widely different digestibilities.

5. The dry-matter content of the faeces of the pigs was remarkably constant over a wide range of water and food intakes when using the same meal.
Fowl semen as collected by the massage method
Authors: Lake P. E.
Published: March 2009

1. The reflex ejaculation responses of cocks to lumbar massage have been examined, and some basic reactions described. A list of the crude fluid components obtained by the massage technique of semen collection is given.

2. From these observations, and a chemical test on the contents of the hen's vagina after natural and artificial insemination, it was deduced that the normal ejaculate of the cock is composed mainly of contents from the vasa deferentia, with some secretions from the mucosal glands of the vascular bodies and lymph folds. The blood plasma transudate sometimes expelled into the semen is obtained as a result of compression of the terminal organs during the collection procedure.

3. Points emerging from the observations on ejaculation, and the search for the normal constituents of semen are discussed.
Heritability and combining ability of vegetative and phenological characters of winged beans (Psophocarpus tetragonolobus (L.) D.C.)
Authors: Erskine W.
Published: March 2009

The variability generated in a diallel cross between seven genotypes for vegetative and phenological characters was studied in the F1 and F2 generations in lowland Papua New Guinea. The mean narrow-sense heritability values of mean leaf size and leaf area index at flowering were 88·0 and 78·5%. The parental values of these characters gave good predictability of the performance of the parents in hybrid combination. For mean number of leaves per plant at flowering, environmental effects were of major importance, and consequently selection between crosses for number of leaves is considered futile. There was a large genotype ˣ environment interaction for time to first flower. The role of various environmental factors in causing the interaction for flowering is discussed.
The effect of drought on the water use and yield of two spring wheat genotypes
Authors: Innes P. , Blackwell R. D.
Published: March 2009

Automatic plot covers were used in a study of the effects of drought on the yield and water use of two spring wheat genotypes. The experiment tested the effects of drought at different stages of growth on yield and yield components. There was complete control over the water supplied to the plots, and a fully irrigated control treatment was included.

The yields of the two genotypes were similar under fully irrigated conditions, but the yield components differed: Highbury had more grains per ear and TW 269/9/3/4 more ears per unit ground area and a higher mean grain mass. An early drought, which began 4 weeks before anthesis, caused a reduction in number of grains per ear in Highbury, which was outyielded by TW 269. Late drought also reduced yields differentially, reducing mean grain mass, and hence grain yield, more in TW 269 than in Highbury. Total shoot dry matter and grain yield were found generally to increase as water use increased. The average water use efficiency was found to depend upon the genotype and treatment.
The effect of different levels of nutrition at two stages of the lactation on milk production and live-weight change in Friesian cows and heifers
Authors: Strickland M. J. , Broster W. H.
Published: March 2009

Over the 4 years 1965–8, a total of 105 mature Friesian cows and 84 Friesian heifers were fed various levels of nutrition at two stages of the lactation to study the effect on milk production. The experiments were carried out over a whole lactation at four Experimental Husbandry Farms, Boxworth, Bridget's, Great House and Trawsgoed. There were three treatment levels in early lactation (weeks 3–10) comprising 5·9, 7·8 or 9·8 kg D.M./day of concentrates for mature cows and 1·6 kg D.M./day less at each level for the heifers. In mid-lactation (weeks 12–18) the two lower levels of concentrates were fed arranged factorially with early-lactation levels. A basal forage ration usually of hay was fed to provide 85% of the basal maintenance requirements. During the remainder of the lactation all animals received the same level of nutrition. In addition to the pre-determined feed treatments, one further group of animals in each block was fed according to the milk production in the preceding week.

Overall an increase in level of nutrition in early lactation produced a regular increase in milk production from successive increments with adult cows but only for the first increment with heifers. Raising feed level in mid-lactation increased milk production for all animals. There were considerable residual effects from early-lactation feeding but these were less with mid-lactation feeding. These same effects were also noted with yields of solids-not-fat and to a less extent in milk fat production.

The experimental results indicated not only the mean effects of treatments but more important the interaction with individual animals. Study of the response of individual animals indicated that the effects of level of feeding varied in proportion to the potential of the cow. The presentation of mean results can therefore be misleading. The potential of a cow was indicated by milk production in the immediate post-calving period. This period could be used both in experimental designs for selecting animals in the allocation to experimental treatments and also in the practical context for rationing individuals or groups of cattle.

The absolute plane of nutrition related to the potential of the animal was the most important factor in determining the efficiency of utilization of feed for milk production.
The biometry of lactation
Authors: Wood P. D. P.
Published: March 2009

A consideration of input-output relationships relating energy intake to its probable utilization for growth, condition and lactation by dairy cows leads to a series of equations describing observable responses. Energy is expressed in terms of units of milk equivalent, common to all equations, and the lactation curve, yn = anò e−cn is shown to be capable of biological interpretation, having regard to the subordinate equations from which it is derived. This expression relates milk production yn during a time interval n through the parameters a, b and c. The validity of the steps by which the function is developed is examined by reference to published work.
Analysis of growth and tuber yield in sweet potato (Ipomoea batatas) cultivars
Authors: Enyi B. A. C.
Published: March 2009

Growth and tuber yield of local sweet potato cultivars were compared during the 1974 and 1975 growing seasons. Three cultivars significantly outyielded the others. The cultivar effect was associated with differences in individual tuber weight, rate of bulking and percentage of total dry matter diverted into the vine or stem. Mean crop growth rate (C) and percentage of total dry matter diverted into the tubers were greater in the higher yielding cultivars and there was positive and significant correlation between Cand final total dry weight. Leaf area duration (D) was greater in 1975 than in 1974 but the differences between cultivars in D was not consistent. Higher yielding cultivars had significantly greater tuber/leaf ratio than the other cultivars.

Bulking rate and tuber weight were positively correlated with tuber yield, while the percentage of total dry matter diverted into the vine was negatively correlated with tuber yield.
The pre-natal development of skin follicles in Mouflon (Ovis musimon) × Soay, Soay and Shetland sheep
Authors: Ryder M. L.
Published: March 2009

Skin was examined from a total of 70 lambs obtained at the foetal age of 75, 90, 100, 120 and 135 days. The rate of follicle development was not greatly dissimilar from that previously described in improved breeds. The Shetland showed least difference from improved breeds, and the Mouflon x Soay was most retarded, but the pure Soay foetuses were closer to the Shetlands than to the Mouflon cross-breds.
In vivoinhibition by specific lipids of ethanol production from glucose by the yeastTorulopsis glabrata
Authors: White R. W.
Published: March 2009

The production of toxic levels of ethanol in the stomachs of neonatal ruminants resulting from fermentation of glucose by resident yeasts occurs only in the absence of fat from the diet. Daily levels of ethanol and numbers of viable yeast were measured on samples of stomach contents for 21-day periods. Milk fat was shown to control the ethanol production in lambs and calves (but notin vitroin culture), the quantitative nature of this control was demonstrated by experiments with cream using lambs. Nine dietary fats in commercial use homogenized in fat-free milk, a commercial catering ‘milk’, and an intravenous lipid feed were all tested in lamb-feeding experiments, compared with whole and separated milk, and an inert oily hydrocarbon, liquid paraffin.
The drifting of honey-bees
Authors: Free J. B.
Published: March 2009

1. Most of the bees which drift do so during their orientation flights and before they become regular foragers.

2. Bees emerging in August and September drift less than those emerging earlier in the year.

3. Drifting varies considerably in different circumstances, and may be extensive.

4. Drones drift two to three times as frequently as workers.

5. An individual bee is more likely to drift from a small to a large colony than vice versa, but the greater number of bees flying from the large colonies may result in a net gain in bees by the smaller ones.

6. When hives are arranged in repetitive patterns, bees drift to hives occupying similar positions in the pattern to their own. When hives are arranged in rows, bees from the centre colonies drift more than those at the end, resulting in the latter colonies gaining numerically. In some circumstances, more bees drift to hives in one direction than in the opposite direction.

7. Facing hives in different directions and painting them different colours considerably reduces drifting, the facing of hives in different directions being of the greater significance.
The relation between respiratory rate and heart rate in the calf subjected to severe heat stress
Authors: Bianca W.
Published: March 2009

1. In experiments on three calves it was shown that, under severe heat stress, the respiratory rate at first rapidly rose from 88 to a maximum of 218 respirations/min. and then fell to 167 respirations/min., while breathing at first became shallower and then deeper.

2. During the phase in which breathing became faster and shallower (panting), the heart rate rose at a mean rate of 13 beats/min. for each degree centigrade increase in rectal temperature. During the phase in which breathing became slower and deeper (‘second-phase breathing’) the mean rate of rise in heart rate was 50 beats/min. for each degree increase in rectal temperature.

3. The changes in respiratory rate and in heart rate occurred at mean rectal temperatures of 40·6 and 41·0° C., respectively, and, on average, the change in respiratory rate preceded that in heart rate by 8 min.

4. It is concluded that second-phase breathing was the cause of the steep increase in heart rate.

5. The steep increase in heart rate is discussed in relation to heat production of the respiratory muscles.
Water relations of winter wheat: 4. Hydraulic resistance and capacitance in the soil-plant system
Authors: Wallace J. S. , Biscoe P. V.
Published: March 2009

A simple model is presented which can account for the hysteresis observed in the relationship between leaf water potential (χ1) and water flow per stem (Q) in winter wheat. Using this model the total hydraulic resistance (R) and capacitance (C) of the soil-plant system were estimated from measured diurnal changes in χ1 and Q. Daily mean values of R were constant when the soil water potential (χ1) was above – 0·6 MPa, but R increased by about 40% when the soil dried to – 1·5 MPa. R also appeared to vary during the day, increasing in the afternoon and evening.

The results of experiments on the recovery of χ1 in plants from which transpiration was prevented suggested that the major resistance to flow was in the soil-root system and that it was an increase in this resistance which gave rise to the overall increase in R as the soil dried.

There was substantial variation in the estimates of hydraulic capacitance (C) and no systematic diurnal or seasonal trend was evident. Despite the variation in C the mean value for the season, 8 x 10-7 m3/MPa, predicted realistic changes in plant water storage. Estimates of the components of C indicated that the major capacitance was located in the soil-root complex. More information is needed about the components of R and C, particularly those in the soil-root system.
Effect of soil acidity factors on nodulation, active iron content of nodules and relative efficiency of symbiotic N2-fixation by mutant strains of Lens esculenta Rhizobium
Authors: Rai R. , Prasad V.
Published: March 2009

Nitrosoguanidine-induced acid-tolerant mutants S1 and M1 of Lens esculenta Rhizobium leguminosarum were used for nodulation and symbiotic N2-fixation in acid soils having different pH and associated factors of acidity. The range of soil pH and associated acidity factors in which nodulation and N2-fixation responded varied, depending on mutant strains. However, strain M1 was more responsive and effective than S1. Antagonistic effect of Mn to Fe was found when the active Fe2+ and total Mn were determined in fresh nodules.
Response of pigeon pea (Cajanus cajan (L.) Millsp.) to plant density and phosphorus fertilizer under dryland conditions
Authors: Ahlawat I. P. S. , Saraf C. S.
Published: March 2009

Field studies were made for 2 years on a sandy loam soil under dryland conditions of north-west India with three pigeon-pea varieties in relation to plant density and the application of phosphate fertilizer. Varieties Pusa Ageti and P4785 with better developed root system and profuse nodulation had higher grain and stalk yield, and higher N and P yield than Prabhat. Root and shoot growth and root nodulation were adversely affected with increasing plant densities in the range 50 × 103 and 150 × 103 plants/ha. Stalk and total N and P yield increased with increasing plant density. Plant density of 117 × 103 plants/ha produced maximum grain yield of 1·53 t/ha. Phosphorus fertilizer promoted root and shoot growth, intensity and volume of nodulation and increased grain, stalk, N and P yield. The effect of plant density on grain yield was more pronounced in the presence of phosphate fertilizer. The economic optimum rate of P ranged between 22·1 and 23·1 kg/ha under different plant densities.
The effects of gibberellic acid upon growth habit and heading in late-flowering red clover (Trifolium pratense L.)
Authors: Stoddart J. L.
Published: March 2009

The response of S. 123 extra-late-flowering red clover in the year of sowing to three sprayings of gibberellic acid (GA) given at 28-day intervals is described. Plants in both soil and vermiculite cultures were used.

1. The first effects, noticeable in the basal rosette, were an increase in petiole length and a parallel increase in leaf area.

2. Fewer stems were formed on the treated plants but their thickness and the number and length of the internodes were increased.

3. Secondary branching was not significantly increased but the GA-treated plants produced a large number of tertiary branches from axillary buds on the secondary branches. Tertiary branching was not frequent in the control plants.

4. Cauline leaves showed an increased length/breadth ratio at each node with treatment, elongation tending to be most marked at those nodes where leaf formation coincided with GA sprayings. Leaf thickness was also increased by GA treatment.

5. Treated plants produced nearly 80% more heads, and flowering after GA treatment was up to 14 days earlier than the control.
The value of calcium nitrate for spring-sown cereals
Authors: Widdowson F. V. , Penny A. , Williams R. J. B. , Cooke G. W.
Published: March 2009

1. Seven experiments on spring barley and five on spring wheat carried out in 1955–7 compared dressings of ammonium sulphate and calcium nitrate applied to the seedbeds at 0·3 and 0·6 cwt. N/acre. The fertilizers were tested both when broadcast and when drilled with the seed.

2. Consistently higher yields of barley were produced by drilling than by broadcasting ammonium sulphate. Drilling calcium nitrate at 0·3 cwt. N/acre was superior to broadcasting for barley but when applied with the seed at 0·6 cwt. N/acre this fertilizer retarded germination and early growth and gave smaller yields than were obtained by broadcasting. Broadcast dressings of both fertilizers gave higher yields of wheat than combine-drilled dressings. There is a considerable risk of fertilizer ‘scorch’ when compound fertilizers containing all their nitrogen in nitrate form are combine-drilled at rates sufficient for maximum yield. This risk may be discounted when adequate rain follows drilling but the check to germination may be sufficient to reduce yields in dry springs, on light soils, and on badly prepared seedbeds. Fertilizers containing all their nitrogen in ammonium form appear to be quite safe at the rates of dressing tested in this work.

3. Calcium nitrate and ammonium sulphate gave similar yields and nitrogen contents of both crops when the fertilizers were broadcast on the seedbed. Nitrates applied at sowing-time to cereals grown in the drier parts of the country do not appear to be leached out of the root-zone before they can be taken up by crops.
Counting blood cells of chickens
Authors: Chubb L. G. , Rowell J. G.
Published: March 2009

1. Six methods of diluting chicken's blood prior to counting erythrocytes and leucocytes in haemacytometers have been studied. No difficulty is found in recognizing erythrocytes. The most satisfactory method of counting leucocytes was the method described by Natt & Herrick (1952) in which the diluent contains methyl violet. Formulae are given which enable standard errors of estimates to be calculated.

2. Three methods of staining blood smears for the differentiation of the various leucocytes have been studied. The method using Leishman's stain appeared to result in good differentiation and was simple to use. However, an experiment to study sampling errors has shown that there may be considerable differences between observers in the percentages of lymphocytes and heterophils when the latter are high, showing that the estimates of these quantities may be biassed. These differences may have been caused by a tendency for heterophils to concentrate to the edges of the smears and for the observers to select different fields for their counts.

3. Although blood counts varied only slightly during the day, there were considerable differences from day to day. The average erythrocyte count for ten chickens fluctuated between about 2·9 and 3·5 millions per mm.3 during the first 3 weeks after hatching and was more steady for the next 4 weeks at about 2·9 millions per mm.3. The average leucocyte count rose from about 10,000 to 35,000 per mm.3 during the first 7 weeks of life, the rate of increase being greatest when the chickens were youngest; the rise was mainly due to a rise in the number of lymphocytes.

4. There were also considerable differences in blood counts between chickens even though environmental and genetic conditions were standardized as far as possible.
The effect of copper therapy on the growth rate and blood composition of young growing cattle
Authors: Givens D. I. , Hopkins J. R. , Brown Marjorie E. , Walsh W. A.
Published: March 2009

A total of 187 animals (mainly Friesian dairy heifers) on nine farms in Wharfedale, Nidderdale, Calderdale and the Vale of York were weighed, condition scored and blood sampled on three occasions during the grazing season 1977. On each site, half of the animals each received two injections of a Cu preparation (200 mg Cu total), one in May and one in July. Herbage samples were taken in May, July and September.

Despite the fact that many animals started the experiment with low blood total Cu concentrations, growth rates during the experimental period were all satisfactory (lowest mean value 0·70 kg/day) with a significant increase due to treatment being observed on only one site. The Cu treatment, however, had a significant effect on blood and plasma total Cu values with the treatment either increasing the level to normal in animals which had started with low values, or maintaining the value in animals starting with near normal concentrations. On certain sites, animals in the untreated group ended the experiment with very low blood and plasma total Cu values (0·02–0·03 mg/100 ml). To prevent the possibility of a Co deficiency on some sites interfering with the experiment, all animals received a Co bullet initially. Despite these, concentrations of vitamin B12 in serum samples taken during and at the end of the experiment were low by present interpretation. This suggests either that Co bullets were an ineffective treatment or that the present interpretation of serum vitamin B12 concentration in bovines is incorrect.

The calculated concentrations of available Cu estimated from herbage analysis indicated that on most sites the value was below the optimum for the growing cattle under study. The results of the experiment suggest that even when blood Cu values and herbage available Cu values are low a growth response to Cu injections may not occur over the course of a grazing season.
The effects of selection for number of ears on the yield and water economy of winter wheat
Authors: Innes P. , Blackwell R. D. , Austin R. B. , Ford Margaret A.
Published: March 2009

Selections for high (H) and low (L) number of ears were made from crosses between three pairs of winter wheat varieties. By the F5 generation there were consistent, heritable differences between H and L selections in each cross. In an irrigated trial the H lines outyielded the L lines even in one experiment where compensatory increases occurred in the weight of grain per ear of the L lines. Drought for the 5 weeks before an thesis reduced the final number of ears of the H lines by 14% but did not affect the final number of ears of the L lines. This reduction in the final number of ears of H lines resulted in them being outyielded by L lines by 8%. Drought from anthesis to maturity did not significantly reduce grain yields of either H or L lines below their values under full irrigation.

When fully irrigated, the evapotranspiration of H and L lines from 1 April until maturity was approximately 360 mm. The drought before anthesis reduced water use to about 320 mm, there being no difference between selections in total water use by the crops during this period. However, the L lines extracted significantly more water from the soil below a depth of 0.9 m during this drought than the H lines, and this appeared to make the L lines less susceptible to drought at this stage. Water use by the crop during the late drought could not be reliably estimated because by this time water was being extracted from below the level of the neutron probe access tubes.

It is concluded that in an environment where a pre-anthesis drought is unlikely to occur, varieties with high ear-bearing capacity may give the best yields. Selection for types showing a limited tillering capacity may prove to be an effective compromise in regions with erratic rainfall where pre-anthesis droughts can occur.
Cultivation systems for spring barley with special reference to direct drilling (1971–1974)
Authors: Hodgson D. R. , Proud J. R. , Browne S.
Published: March 2009

Five cultivation systems for spring-sown barley were tested on a clay to sandy-clay loam for 4 years and their cumulative effects on soil and crop measured. Four primary cultivations in the autumn, shallow (7·5 cm), medium (15 cm) and deep (23 cm) tine cultivation and mouldboard ploughing (23 cm deep) followed in spring by secondary cultivations and sowing, were compared with direct drilling seed into uncultivated soil after controlling weeds with herbicides. At the same rates of seed and fertilizer for all systems, direct drilling and shallow cultivation yielded significantly less grain than deeper tillage in the second year only; over 4 years the differences in mean yield were small and non-significant. In terms of crop output per unit of implement net energy (estimated) direct drilling was eight times more efficient than ploughing.

Direct drilling and shallow cultivation caused concentration gradients of ‘available’ phosphorus and potassium to form in the top soil. Soil strength and to a lesser extent bulk density were greater without than with cultivation but these changes had only a relatively small effect on root distribution in the profile. In untilled soil the proportion of the root system was less in the surface 2·5–12·5 cm and greater in the 12·5–32·5 cm horizon than in shallow or deep tilled soil.

Mean nitrogen uptake by the crop in the third and fourth seasons was least in direct - drilled barley probably due to lower rates of mineralization of soil nitrogen in compacted than tilled soil. It was deduced that for spring barley the ‘yield plateau’ was the same for each system but that optimal rates of nitrogen would be higher for crops in untilled than tilled soils.
Inheritance of resistance to cow-pea weevil (Callosobruchus maculatus, Fabr.)
Authors: Fatunla T. , Badaru K.
Published: March 2009

Four bruchid-susceptible and four bruchid-resistant cow-pea cultivars were crossed to produce 16 F1s and their reciprocals. From each cross, six generations, P1, P2, F1, F2, BC1, BC2, were obtained. Each cross was fitted to the additive-dominance model. Estimates of additive and dominance variances were obtained from the half and full sib analyses of the F1s and their reciprocals respectively. It was demonstrated that resistance to cow-pea weevils has additive, dominance and maternal components.
The relationship between post-parturient fatty liver and blood composition in dairy cows
Authors: Reid I. M. , Rowlands G. J. , Dew A. M. , Collins R. A. , Roberts C. J. , Manston R.
Published: March 2009

The blood composition of 45 cows with more than 20% fat in the liver (moderate fatty liver) was compared with that of 83 cows with less than 20% fat in the liver (mild fatty liver). The cows were sampled at 1 week after calving and were from three Friesian and one Guernsey herds. Blood concentrations of non-esterified fatty acids, bilirubin and aspartate amino-transferase were significantly elevated in cows with more than 20% in the liver whereas concentrations of glucose, cholesterol, albumin and magnesium were all significantly reduced. Blood samples from cows in two of the herds were analysed for ammonia, insulin and D(-)3-hydroxybutyrate. Cows with moderate fatty liver in these two herds had significantly lower insulin concentrations and higher D(-)3-hydroxybutyrate concentrations than those with mild fatty liver. Using an equation based on blood concentrations of non-esterified fatty acids, glucose and aspartate aminotransferase it was possible to assign correctly three out of four cows to either the mild or moderate fatty liver groups.
The relationship between total seasonal rainfall and yield of maize in the Kenya highlands
Authors: Glover J.
Published: March 2009

A study of the climate within the maize-growing areas of the West Rift area of the Kenya Highlands showed that rainfall is the major meteorological variable.

A further investigation showed that average yields of maize in subdistricts within the region are markedly affected by changes in seasonal rainfall and are apparently unaffected by large changes in acreage planted from year to year over a period of eleven years.
The significance of grading-up in the Ayrshire cattle population of Great Britain
Authors: Wiener G.
Published: March 2009

The grading-up system, in the Ayrshire Cattle breed, whereby the descendants of non-pedigree cows enter the registered (Herd Book) population, is studied principally from three aspects: (1) its numerical importance in the population; (2) the breeding structure of herds practising grading-up, and (3) the possible genetic effect of grading-up on milk and fat yield.

Cows at various stages of grading-up are noted in an Appendix to the Herd Book. The numerical importance of the grading-up system has varied with the rate of expansion of the breed as a whole—being greatest during the most rapid expansion—but, at all times, Appendix cows have had more registered female offspring than have pedigree cows. The volume of grading-up was regulated by the number of cows in Appendix B. Some 6% of the pedigree females registered in the last 30 years have Appendix A mothers and a further 5% or so owe their existence to grading-up during the last 30 years.

On average, the proportion of herds registering bulls is not greatly different among the herds which grade-up and those which do not. Similarly, the ratio of males to pedigree females registered was about the same in both types of herd. None-theless, there appears to be considerable selection against Appendix animals in the ancestry of bulls compared with cows, and none of the large bullbreeding studs appear to pursue a grading-up policy. A greater proportion of Ayrshire herds were grading-up in Scotland than in England.

Entry into Appendix B of the Herd Book is confined to cows reaching a qualifying yield. The daughters (A) of these B cows mated to unselected pedigree bulls were found to yield significantly more in their first lactation (36 gal. milk and 14 lb. butterfat) than contemporary pedigree Ayrshire heifers in the same Scottish milk recorded herds in 1955. Part, if not all, of this superiority is thought to be genetic.
The effect of dietary intake of calcium and phosphorus on the absorption and excretion of phosphorus in chimaera-derived sheep
Authors: Field A. C. , Kamphues J. , Woolliams J. A.
Published: March 2009

The effect of ratios of calcium to phosphorus in the diet (varying from 0·6 to 3·6) on the absorption and excretion of P was investigated with four sets of 9-month-old chimaera-derived triplets. A pelleted cereal-based diet supplemented to contain 1·5, 3·1 or 6·2 g P/kg D.M. and 3·4 or 5·4 g Ca/kg D.M. was used in a factorial design.

The additional Ca in the diet reduced the efficiency of absorption of the P supplements in the diet by 0·18 ± 0·04.

The efficiencies of absorption of total P were very similar within but markedly different between (P < 0·001) sets of triplets, the mean values being 0·62, 0·74, 0·82 and 0·84. The fractional absorption of inorganic P alone showed the same ranking and the mean values were 0·47, 0·67, 0·85 and 0·92. These differences between triplets support the view that the individual differences in P metabolism have a genetic basis. The mean absorbability of P in the basic diet (0·77) and in the P supplements (0·73) were similar.

The pattern of excretion of absorbed P between the faecal and urinary route of excretion varied between the sets of triplets; as P intake increased, the additional absorbed P was excreted in faeces by one set, in urine by another and in faeces and urine by two sets. The relative importance of the faecal route was dependent upon the fractional absorption of P secreted into the gut.
Response of wheat cultivars to dates of sowing under dryland conditions
Authors: De R. , Saran G. , Turkhede B. B. , Lal R. B. , Singh R. K. , Giri G.
Published: March 2009

Field experiments made for 4 years between 1976–7 and 1979–80 in a semi-arid environment of north-west India showed that the productivity of dryland unirrigated wheat can be increased considerably by adjusting the date of sowing to conducive atmospheric temperatures. Sowing in the middle of November when daily mean temperatures ranged between 19 and 21 °C produced yields ranging between 2·6and 3·5t/ha (averaged over the 4 years) compared with 1·4–3·3 t/ha obtained from the crop sown by mid-October when the daily mean temperature ranged between 24 and 26 °C. The tall cultivar C 306, a derivative of winter x spring wheat cross, could withstand sowing at higher temperatures (mid-October) more than the spring wheats. High temperatures prevailing during the seedling stage of spring wheats shortened their vegetative growth and initiated early differentiation. Night temperatures above 13 °C coupled with day temperatures of 33–35 °C in the last fortnight of October adversely affected the tillering of spring wheats sown on 15 October and produced smaller spikes with few fertile spikelets.
Compensatory growth and yield of pigeon pea (Cajanus cajan) following pod removal at different stages of reproductive growth
Authors: Tayo T. O.
Published: March 2009

All the pods on pigeon-pea plants were removed after 1, 2 or 3 weeks of flowering in a pot experiment and in one field trial, in order to evaluate the compensatory ability of the crop under humid tropical conditions.

Pod removal after 1 or 2 weeks of flowering led to an immediate significantly higher vegetative development and dry-matter accumulation compared with the control. Subsequent flowering led to greater pod production and pod yield than the control with seed yield increased by 21 and 50%, respectively, in the pot experiment while pod removal after 1 week of flowering increased seed yield by 15% in the field. The removal of pods after 3 weeks of flowering was detrimental to subsequent pod development and seed yield which was decreased by 56 and 34% in the pot and field experiments, respectively.

It would seem that the loss of pods produced soon after flowering starts, before active pod filling begins, can be tolerated by pigeon peas, whereas the loss of fully elongated and actively filling pods would significantly reduce seed yield in the crop.
Endocrine relationships in the induction of oestrus and ovulation in the anoestrous ewe
Authors: Robinson T. J.
Published: March 2009

1. A total of forty-two Suffolk cross-bred and 230 stud Romney Marsh ewes were used in four experiments in which pregnant mare serum gonadotrophin (p.m.s.) was used in various combinations with progesterone and oestrogen in attempts to induce fertile mating in anoestrus.

2. Groups of six Suffolk cross-bred ewes were injected with 1000 i.u. p.m.s. after pretreatment, commencing 4 days earlier, with 75 mg. progesterone administered in one of four different ways. Six twice-daily injections in oil resulted in oestrus in five ewes in each of two groups treated. Single injections in oil solution, aqueous suspension, and benzyl alcohol emulsion resulted in oestrus in two, nil, and four ewes, respectively. All were served within 48 hr. of injection of p.m.s.

3. Ovulation was observed in five of six crossbred ewes which received six twice-daily injections of progesterone in oil, without subsequent injection of p.m.s. Three were served.

4. Divided injections of progesterone commencing 4 days before 750–1000 i.u. p.m.s. failed to induce a satisfactory oestrous response in Romney Marsh ewes. An increase to 7 days in the duration of progesterone stimulation resulted in oestrus in all of eighteen ewes treated.

5. The injection of a benzyl alcohol emulsion containing 75 or 150 mg. progesterone, given as a single dose 4 or 7 days before 750 i.u. p.m.s., failed to induce a satisfactory oestrous response. Of seventy-two ewes treated, only seven were served.

6. Lambing results were most unsatisfactory when progesterone-p.m.s. treatment was followed by artificial insemination. Of 144 Romneys inseminated, only twelve lambed. Successful pregnancy appeared unrelated to the type of treatment or the occurrence of oestrus.

7. On the basis of the oestrous responses observed after the injection of a variety of combinations of oestrogen, progesterone, and p.m.s., and by reference to quantitative data on progesterone-oestrogen relationships in oestrous behaviour in the spayed ewe, it is concluded that the developing follicle of the Romney Marsh ewe produces an amount of oestrogen approximately equivalent, in its physiological activity, to a single injection in oil of about 20 μg. oestradiol benzoate.
The achievement of very high yields of potatoes in the U.K.
Authors: Evans S. A. , Neild J. R. A.
Published: March 2009

Crops of potatoes grown on 0·2–0·3 ha in each of the years 1971–8 at Stockbridge House Experimental Horticulture Station achieved total tuber yields of 70–94 t/ha. Yield was determined by the period and rate of tuber growth. The observed period of growth varied from 96 to 132 days and the rate from 0·55 to 0·90 t/ha/day. Rate of growth had the greater influence on variability of yield between the years. The number of tubers produced per unit area had little influence on their total weight, but had marked effect on their size. Adequate water supply was essential for very high yields. Experiments indicated that current recommendations for potash fertilizer can be adequate but that nitrogen and phosphate fertilizer use may need to be enhanced for very high yields. For high yields, the number of seeds planted per hectare may need to be higher than normally recommended in order to avoid the production of large tubers unsuitable for the ware market.