bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling the field drying of hay
Authors: Thompson N.
Published: March 2009

The loss of moisture from swaths drying in the field has been investigated using bulk and multi-layer micrometeorological models of an idealized swath. The models produced almost identical results for the variations with time of the swaths' mean moisture contents but the multi-layer version showed in addition the results to be expected from tedding, and the effects of transpiring stubble and evaporation from an underlying moist soil surface on swath drying. The models reproduced in broad detail changes of swath moisture, including rain and dew intercepted by the swath, which had been observed in experiments on grass wilting. However, there appeared to be under-estimation of the rate at which the swath tissue absorbed moisture when the swath contained surface water. The bulk model reduces to a very simple formula when used with typical swath resistances, revealing the importance of both sunshine and vapour pressure deficit in promoting drying, and demonstrating the adverse effect of wind; the model lends itself to the routine classification from daily climatological data of days suitable for hay drying.
Eating and rumination behaviour in sheep given silage made from the fibrous residue of ladino clover
Authors: Fujihara T.
Published: March 2009

It appears that in ruminant animals one of the important effects of rumination is to decrease the particle size of the diet (Pearce & Moir, 1964; Gordon, 1968; Welch & Smith, 1969). This thesis is borne out by Gordon (1958) who showed that grinding a dried-grass diet markedly reduced rumination. Therefore, it is fair to assume that rumination behaviour is, at least in part, concerned with changing the physical properties of food, especially roughage, so that digestion and utilization are improved. Fujihara (1980) observed more efficient rumination in fresh-grass feeding than with hay in sheep given either fresh grass or hay alone, diets clearly differing in physical properties.
Photolysis and degradation of Thanite in cotton plants and artificial rumen
Authors: El-Sebae A. H. , Aal M. Abd El , Marei A. S. M. , Tantawy G.
Published: March 2009

Thin-layer chromatography and infra-red spectrosoopy were used to identify the components of technical Thanite. A method is developed for qualitative and quantitative determination using a gas liquid chromatograph (GLC) equipped with a flame ionization detector. Two major peaks, having retention times 1 and 5 min, were obtained. This was achieved using a glass column (15 × 0·3 cm), packed with diethylene glycol (1·5%) on chromosorb W, 60–80 mesh, at temperature range 70–170 °C. The results obtained by GLC showed that 33·7–55·8%, and 36·6–68·3% of the initial deposit of Thanite on cotton leaves degraded within 12 h from exposure to sunlight and ultraviolet irradiation respectively. One fifth of the initial deposit of Thanite on cotton leaves was lost after 24 h from spraying, then 70 % of the compound was dissipated after 3 days. Incubation of Thanite with rumen liquor at 39 °C for 24 h under anaerobic conditions resulted in degradation of 45–74% of the initial concentration.
The effects of light illuminance and wavelength on the growth of broiler chickens
Authors: Wathes C. M. , Spechter H. H. , Bray T. S.
Published: March 2009

The effects of light illuminance and wavelength on the growth of male and female broiler chickens from day-old to 8 weeks of age were studied.

Different coloured lights, at equal illuminance and peak wavelengths of 425, 525 and 610 nm and a broad-spectrum white light of median wavelength 560 nm had no significant effect on the growth rate or cumulative food intake of birds of either sex.

The performance of male broilers was unaffected by light of different illuminances, equal to 0·7, 3·0, 15·0 and 46·5 lux. The weight gain of female broilers, adjusted for food intake, was progressively depressed at illuminances above 3 lux.

There is probably no commercial advantage in using broad-spectrum white light at intensities above 3 lux.
Effect of water deprivation on urinary concentrations of creatinine and nitrogen in sheep
Authors: More T.
Published: March 2009

It has been reported that water deprivation reduces feed intake in Chokla sheep (Singh, More & Sahni, 1976; More & Sahni, 1978). Consequently, sheep production in terms of body weight, milk and lambs is also adversely affected (More & Sahni, 1980). However, no information is available on the metabolic aspects, particularly on urinary nitrogen and creatinine changes due to long-term intermittent watering. Creatinine is also used as a reference substance for evaluating urinary excretion rates of minerals (Field, 1964) and nitrogen (Powell, Plough & Baker, 1961) to avoid more laborious and time-consuming procedures, which also disturb animal behaviour and production (Langlands, 1966). The present paper attempts to examine the urinary concentration of total nitrogen, creatinine and their ratios; the ratios of potassium to creatinine and nitrogen are also considered.
Growth patterns in sheep: wool growth during weight loss and subsequent compensatory growth
Authors: Butler-Hogg B. W.
Published: March 2009

Wool growth rates (WGR) of individual sheep were measured by a patch-sampling technique, during periods of developmental growth, body-weight loss (which ranged from 21 to 34% of original body weight, at rates between 60 and 150g/day) and subsequent compensatory growth under ad libitum feeding.

There was a ‘lag phase’ of about 30 days before WGR appeared to be affected by changes in direction of the animals' growth paths.

During body-weight loss WGR declined about 300% more than the percentage change in body weight, with the duration of nutritional stress exerting a greater influence than the rate of body-weight loss.

During compensatory growth in body weight, the relationship between WGR and rate of body-weight change was initially negative. Sheep required between 11 and 14 weeks to reach the WGR of 21 g/day found during developmental growth. Compensatory growth of wool did not occur.

Duration of the nutritional stress, rather than its severity (as indicated by rate of body-weight loss), was the more important determinant of the time taken for the sheep to regain normal levels of wool growth after the commencement of ad libitum feeding.
The analysis of data from germination tests
Authors: Hunter E. A. , Glasbey C. A. , Naylor R. E. L.
Published: March 2009

The development of statistically sound methods of summarizing the results from germination tests appears to have been neglected. This paper reviews the literature critically, proposes the use of maximum likelihood techniques to summarize such data and develops an appropriate routine, available as a computer program ‘DISTGERM’.
The effect of different proportions of protein and antibiotic in the diet on reproductive performance of indigenous pigs in Nigeria
Authors: Ilori J. O.
Published: March 2009

One hundred and twelve indigenous gilts and sows were used in two trials to study the effects of strepcillin (a mixture of streptomycin and penicillin) at 0, 25, 50, 75 and 100 g/t feed in a basal 15% protein diet and strepcillin at 0, 25, and 50g/t feed in rations containing 12, 15 and 18% protein, on the reproductive performance of pigs.

Reproductive performance in terms of sow net gain in weight through the reproductive cycle, average birth weight of live pigs per litter and number of pigs weaned per litter were significantly affected by antibiotic levels. The dietary level of 50 g antibiotic/t feed gave the highest reproductive performance though at higher levels no adverse effects on reproductive performance were obtained.

Reproductive performance of pigs was significantly influenced by protein and antibiotic levels. A significant interaction between antibiotic and protein levels was obtained for weight loss in sows at parturition and lactation, net gain in weight through the reproductive cycle, total and live pigs farrowed per litter.
The effect of plane of nutrition on the body composition of two breeds of wearier sheep fed a high protein diet
Authors: Searle T. W. , Graham N. McC. , Donnelly J. B.
Published: March 2009

Corriedale and Dorset Horn castrate male (wether) lambs reared at pasture were weaned at 19 kg live weight (LW), brought indoors and fed a high protein diet such that half of each group grew at ca. 200 g/day and the other half at ca. 100 g/day. Animals were slaughtered at 25 and 30 kg LW and chemical composition (protein, fat, energy, water and ash) of the body determined. The relationship between each body component and shorn empty-body weight was examined by regression analysis.

Within levels of feeding the results were similar in the two breeds. When comparisons were made between feeding levels, the slower-growing animals contained more fat, energy and ash than the faster-growing group, less water, but similar amounts of protein at any given empty-body weight.
Intake and digestion of formaldehyde-treated red clover silages offered to calves either alone or with a urea supplement
Authors: Kaiser A. G. , Osbourn D. F. , England P.
Published: March 2009

In a 3 × 3 latin-square design experiment, 12 British Friesian steer calves with rumen cannulae were offered three red clover silages to appetite, either alone or with a urea supplement of 18.9 g/kg total dietary dry matter (D.M.). The silages were prepared from a second cut of red clover using additives of 2·11 formic acid/t fresh crop together with formaldehyde at 0, 31 or 123 g/kg crude protein (CP) in the crop.

The control silage was well preserved, as indicated by a low content of volatile fatty acids and ammonia N. Formaldehyde treatment generally restricted silage fermentation, although there was an increase in the content of butyric acid at the intermediate level of application, and an increase in 2, 3-butanediol content at the high level of application. A decline in ammonia-N content and an increase in insoluble-N content, with increasing level of formaldehyde application, indicated that formaldehyde had been effective in reducing protein degradation in the silages.

Formaldehyde treatment depressed intake, the apparent digestibility of D.M., organic matter (OM), N, cellulose and energy, and N retention, the effect being particularly evident at the high level of application. Behavioural observations showed an increase in eating time on the formaldehyde-treated silages. Urea supplementation increased intake of the formaldehyde-treated silages, but did not influence intake of the control silage, and increased N retention on all silage diets. Apart from an improvement in apparent N digestibility, urea supplementation did not influence the digestibility of other dietary components.

Within the rumen, formaldehyde treatment reduced ammonia-N concentration and the molar proportions of propionate and butyrate, and increased the molar proportion of acetate. The rate of D.M. and cellulose disappearance from treatment silages suspended in the rumen in nylon bags was reduced by formaldehyde treatment, the effect being most evident at the high level of formaldehyde application. A similar effect on rate of D.M. disappearance was observed when the control silage was placed in nylon bags, indicating that the adverse effect of formaldehyde was probably due to an effect on the rumen environment. Urea supplementation increased rumen ammonia-N concentrations, although this effect was not as great on the high formaldehyde silage, and increased the rate of D.M. and cellulose disappearance from silage in nylon bags.

It appears that the lower intake and the poorer utilization of dietary N on the high formaldehyde silage may have been due to a reduction in the rate of digestion within the rumen. While there was some response to urea supplementation, it could not restore the apparent rate of digestion in the rumen to levels observed on the control diet. Hence, factors other than the supply of rumen-degradable N in the diet must have been responsible for the depression of digestion within the rumen.
Utilization of proteins from milk and raw or acid-treated Toprina yeast by newly born ruminant lambs and growing rats
Authors: Soliman H. S. , Ørskov E. R. , Davies N. T. , McDonald I.
Published: March 2009

Four experiments were carried out to study the possibility of replacing milk proteins for lambs with Toprina yeast (G) grown on hydrocarbons. In Expt 1 the effect of replacing all the milk protein with Toprina was studied in the presence of milk fat or a mixture of lard and coconut fat. In Expt 2 the maximum level of Toprina yeast that could be used was studied. In Expt 3 the effect of treatment of the yeast with acid on the digestion of Toprina proteins in the small intestine of pre-ruminant lambs (fitted with re-entrant cannulae in the terminal ileum) was examined. In Expt 4 the effect of the supplementation of acid-treated yeasts with tryptophane and methionine was studied using growing rats.

The results of Expt 1 showed that lambs given milk diets grew faster (145 v. 80g/day) and converted feed more efficiently than those given Toprina yeast. Apparent digestibility of nitrogen of skim milk was higher (93%) than that of Toprina yeast (84%). The poorest results were obtained from lambs given lard and coconut as the source of fat and Toprina yeast as the source of protein. In Expt 2 it was found that progressively replacing the casein protein by yeast protein (0, 33, 67 and 100%) resulted in a linear reduction in daily live-weight gain, feed conversion and nutrient digestibility, but at 33% replacement of milk protein any effect on lamb performance appeared to be small. In Expt 3 the flow rates of dry matter, nitrogen and its fractions (soluble and insoluble in water) and fats were highest with the raw yeast, intermediate with acid-treated yeasts and lowest with skim milk. Apparent digestibility of nitrogen up to the ileal cannula was 67, 77 and 88% for raw yeast, acid-treated yeast and skim milk respectively.

In Expt 4, raw yeast supplemented with methionine was found to be as good a protein source as casein for growing rats. The supplementation of acid-treated yeasts with tryptophane did not improve rat performance, but supplementation with methionine increased growth rate and improved efficiency of feed and protein utilization. Acid hydrolysis of yeast also improved its nutritive value, but the full improvement was only obtained when the diet was supplemented with methionine.

It is concluded that yeast protein can provide only about one third of the protein in milk replacers for lambs; prehydrolysis of the yeast may help to increase this proportion without reduction in animal performance.
The utilization of the dietary energy of pangola and setaria by young growing beef cattle
Authors: Tudor G. D. , Minson D. J.
Published: March 2009

The net energy values for growth and fattening of two artificially dried tropical grasses-, pangola (Digitaria decumbens) and setaria (S. sphacelata var. sericea cv. Nandi), of similar estimated metabolizable energy content (8·07 and 7·96 MJ/kg D.M.) were determined with cattle using a slaughter technique. Growing cattle with a mean initial weight of 175 kg were given equal quantities of dry matter of the two grasses at each of three planes of nutrition above maintenance for a period of 152 days.

The initial energy, fat and protein content of the total body of the 24 test animals was estimated from regressions relating fasted live weight to theśe components, derived from 12 similar cattle slaughtered at the beginning of the feeding period. The final energy, fat and protein content of the test animals was determined directly by chemical analysis. The metabolizable energy (ME) content of the grasses was estimated from the level of digestible energy (DE) determined with eight cattle, assuming that ME = 0·815 DE.

The cattle fed pangola gained more live weight, empty-body weight, fat, protein and energy than animals fed similar quantities of setaria. The net energy value for growth and fattening (NEf) was determined using regressions relating energy retention to the quantity of dry matter eaten. NEf in MJ/kg dry matter was 2·27 for pangola and 1·31 for setaria.

Efficiency of utilization of ME for growth and fattening (kf) was.27·7% for pangola and 16·9% for setaria. These values for tropical grasses are lower than any values reported for temperate pasture species. Thus the lower efficiency of utilization of ME may cause the lower production of cattle which graze tropical grasses.

It was concluded that as the kf values of different tropical grasses are not constant, kf values should be measured on a wider range of tropical grasses so that this factor can be taken into account when evaluating grasses in animal production systems.
Winter survival and spring growth of white clover cultivars at an upland site in northern England
Authors: Haycock R. , Ollerenshaw J. H.
Published: March 2009

One of the major limitations of white clover in Britain is the delay in commencement of spring growth compared with companion grasses (Williams, 1970) and the delay is further increased. by the resulting competitive disadvantage (Davies & Young, 1967; Spedding & Diekmahns, 1972). Thus there is a need to increase growth of white clover at low temperatures particularly in the uplands where the season is short (Ollerenshaw & Baker, 1981). However, the work of Cooper (1964) suggests that increased spring growth rate will be detrimental to survival. Small-leaved cultivars, e.g. S.184, have been favoured for upland use because they are well able to survive. This paper presents a study of the survival and early spring growth of 13 commercial varieties of white clover. Early spring growth was described by the increase in numbers of leaves per growing point and lamina length. The density of growing points was not recorded as previous field studies (Haycock, 1980, 1981; Davies & Evans, 1982) showed this variable to be of minor importance in spring yield increase.
On the analysis of replacement series diallel experiments
Authors: Sinclair D. F. , Gleeson A. C.
Published: March 2009

The analysis of plant competition experiments in which all possible pairs ofpgenotypes are grown in replacement series is discussed. Two methods of analyses, using models of de Wit (1960) and Gleeson & McGilchrist (1980), are compared. The two approaches, which are shown to be linked algebraically, complement each other in terms of agronomic interpretation.
The estimation of energy expenditure from heart rate measurements in working oxen and buffalo
Authors: Richards J. I. , Lawrence P. R.
Published: March 2009

The heart rates and corresponding energy expenditure of adult Brahman cattle (Bos indicus) and water buffalo (Bubalus bubalis) were measured whilst they were standing, walking at speeds of up to 1 m/sec and pulling loads of up to 50 kg for periods of 1–2 h/day. Correlations of heart rate with energy expenditure showed a positive linear relationship within species although a distinct difference was exhibited between species. However, when heart rate and energy expenditure were expressed relative to their respective resting values (RHR and REE respectively), the results for all animals fitted the same line:

REE = 2·251 RHR – 0·954 (r = 0·93; n = 49).

More importantly, the relative heart rate and actual energy expenditure per unit metabolic body weight (EEW) for all animals fitted a common line:

EEW = 24·94 RHR – 16·25 (r = 0·91; n = 49),

where EEW is in watts/kg0·75 and RHR = heart rate of the working animal/heart rate at rest. This assessment of the energy expenditure from measurement of heart rate and live weight thus allows a prediction to be made of the energy requirements of working draught cattle under field conditions.
The significance of the thickness of cattle skin
Authors: Dowling D. F.
Published: March 2009

The skin is thin at birth. Seasonal variations and changes in the plane of nutrition affect the skin thickness. The differences in skin thickness between breeds of both B. taurus and B. indicus species, are highly significant. Both thin and relatively thick hides may be associated with any combination of milk and beef, early and late maturity, temperate and tropical type cattle.
Nitrogen metabolism of cattle in East Africa:I. The problem and the experimental procedure
Authors: Livingston H. G. , Payne W. J. A. , Friend M. T.
Published: March 2009

The difficulties in the semi-arid regions of East Africa where cattle exist during the dry season on forage with a very low nitrogen content is discussed
Heat tolerance in Southern Rhodesian sheep fed on a maintenance diet
Authors: Quartermain A. R.
Published: March 2009

1. Heat tolerance in nine hair-coated wethers on a maintenance diet was studied during the hottest period of the year near Salisbury, Southern Rhodesia.
Studies on the muscless of meat animals:V. Inter- and intra-litter differences in the composition of Longissimus dorsi muscles from pigs
Authors: Lawrie R. A. , Gatherum D. P.
Published: March 2009

1. The percentage of intramuscular fat (and its iodine number), of moisture (fat-free), and of total, myofibrillar, sarcoplasmic, stroma and non-protein nitrogens in lumbar 1. dorsi muscles, and their ultimate pH, fibre diameter, cross-sectional area and weight (both absolutely and as a percentage of the total musculature) were determined at bacon weight in two male and two female litter-mate pigs from each of four pure-bred sows mated with one boar of the same breed. Such data were obtained for pigs of Large White, Landrace and Welsh breeds.
Studies on growth and symbiotic nitrogen fixation of Rhizobium of Vigna radiata under stress conditions
Authors: Rai R. , Prasad V.
Published: March 2009

One fast-growing acid-producing Rhizobium strain 995 of Vigna radiata was screened for growth behaviour in acid, saline and alkaline media. It grew well in yeast-extract mannitol broth of wide pH range as well as varying concentrations of NaCl, Na2SO4 and MnCl2. Variation in nodulation and N2-fixation efficiency occurred on different varieties of green gram, while strain characteristics were not affected by soil stress.
Factors causing small curds in cauliflower crops
Authors: Crisp P.
Published: March 2009

Vigorous cauliflower plants sometimes bear abnormally small curds, yet this common problem has received little recognition or attention from research workers. Curd size is often reduced towards the end of the harvesting period of a crop, and this is more marked if environmental conditions reduce mean curd size and lengthen the time to maturity. Small late curds may be a consequence of their slow growth rather than their late initiation. Cultivars differ in their tendency to produce plants with late maturity and small curds. This may not be due to genetic differences within cultivars. Moreover, breeding to eliminate or reduce this condition may not be possible without affecting overall maturity time and curd size.
Inoculation of white clover with different strains of Rhizobium trifolii on a mineral hill soil
Authors: Mytton L. R. , Hughes D. M.
Published: March 2009

S.184 white clover was established on an unimproved brown earth hill pasture using both surface seeding techniques and conventional cultivation. Inoculation with selected Rhizobium trifolii improved clover dry-matter production by 0·017 t/ha on the cultivated trial in the establishment year and by 0·13 t/ha in the first harvest year. On the uncultivated site, clover dry-matter production was increased 1·88 t/ha by the best inoculation treatment in the first harvest year and 1·01 t/ha in the second harvest year. Rhizobium strains differed in their ability to promote clover growth. Clover yields were substantially better on the uncultivated than on the cultivated trial. The implications of the results for hill land pasture improvement are discussed.
Effect of irrigation on reproductive efficiency of bunch and spreading types of groundnut (Arachis hypogaea L.)
Authors: Bhatia V. S. , Bhargava S. C. , Sinha S. K.
Published: March 2009

Groundnuts are mostly grown during the rainy season (kharif) in India. Most of the cultivation is without irrigation. Consequently the crop experiences water deficits of different intensities and durations, depending upon the rainfall distribution. Yields are poor under such conditions. In other leguminous species irrigation at flowering usually improves yield, if the pod development period coincides with a break in rainfall or water deficit (Khanna-Chopra, Koundal & Sinha, 1980). Thus, an understanding of reproductive behaviour and reproductive efficiency could be helpful in adjusting planting to coincide with favourable agroclimatic conditions. Alternatively, this understanding could help in scheduling irrigation.
The design and conduct of experiments to measure animal and herbage production responses to fertilizer nitrogen under cutting and grazing managements
Authors: Large R. V. , Cobby J. M. , Baker R. D.
Published: March 2009

Two experiments were conducted to provide information on the precision of herbage sampling, the degree of replication and the logistics of managing rotational and continuous grazing experiments. In a third experiment the possibility of estimating herbage growth, during the rotational grazing of paddocks for 4 days, by linear extrapolation of measured growth estimates made during the interval between grazings was investigated. A fourth experiment was then conducted to investigate animal and herbage production responses to nitrogen applied at five levels over the range 80–900 kg N/ha with three replicates per treatment.

Results from Expts 1 and 2 showed that similar precision could be obtained under both rotational and continuous systems of grazing with the same number of replicates and samples of herbage. There was little advantage in having more than three replicates and four samples per paddock or two replicates and eight samples per paddock. Under continuous grazing a 3-weekly sampling and movement of exclosure cages was indicated. It was also found, from Expt 3 that, under rotational grazing, linear extrapolation of growth from 0–24 days did not reflect growth to 28 days in a consistent manner. Six animals per treatment, permanently in the paddocks, proved adequate for the estimation of live-weight gain.

Experiment 4 confirmed that response curves could be fitted with an acceptable degree of precision if there was one low, one very high, and two intermediate levels of nitrogen. Adjustment of the number of animals to maintain sward height at between 5 and 7 cm ensured similar sward conditions and rates of live-weight gain across all treatments.

The problems associated with the measurement of herbage production under grazing are discussed.
Seasonal influences in milk production in Friesian-Bunaji crosses in northern Nigeria
Authors: Alhassan W. S. , Buvanendran V. , Ehoche O. W.
Published: March 2009

It has been found from controlled environment studies that high temperatures lead todepressions in milk production (Johnson, 1965; Hafez, 1968; McDowell, 1972). Under outdoor situations where all climatic variables may act simultaneously on the animal, responses may vary from the classical chamber studies.
Growth patterns in sheep: changes in the chemical composition of the empty body and its constituent parts during weight loss and compensatory growth
Authors: Butler-Hogg B. W.
Published: March 2009

Chemical compositional (protein, fat, ash and water) changes in the fleece-free empty body, carcass, viscera and ‘remainder’ components of Corriedale wether sheep were measured by serial slaughter of animals following five different growth paths.

The composition of sheep, after losing up to 34% of body weight over 18 weeks at 125 g/day, was significantly different from a continuously growing control group at the same body weight, but the actual differences in the weights of tissues were small. At the end of weight loss all treatment sheep contained more fat and protein, and less water than controls.

The different growth paths followed during weight loss led to differences in the proportions of protein, fat, ash and water lost and to differences between the three body components in the relative contribution made by each.

The periods of weight loss led to changes in the relative growth coefficients for chemical constituents during realimentation, particularly those of fat and ash which were reduced, and of water which was increased.

The response to realimentation differed between body components, particularly the carcass and viscera. Above the body weight at which weight loss was imposed the realimented sheep did not differ in chemical composition from the continuously ad libitum fed controls when compared at the same weight.
Oestrous and ovarian activities of Finn-cross ewes during the post-partum and the seasonal anoestrous periods
Authors: Amir D. , Rosenberg Miriam , Schindler H.
Published: March 2009

The seasonal and post-partum oestrus occurrence and ovarian activity, assessed by the plasma progesterone concentrations, were studied in Finn-cross ewes following autumn and winter lambings.

The last seasonal oestrous cycle was followed by a silent ovulation in C0% of the Finn × Awassi ewes. Silent ovulations during midanoestrus occurred in 50% of the ewes, and in 90% of the animals a silent ovulation preceded the normal resumption of the seasonal sexual activity.

The first post-partum oestrus occurred within C0 days after October lambings in about 90% of the ewes. Silent ovulations before the first post-partum oestrus were evident in 70% of the recycling ewes.

It is suggested that breeding ewes with ovarian activity after oestrus induction during anoestrous periods might increase the reproductive performance of the flock in a frequent lambing system.
Water use by winter wheat as affected by soil management
Authors: Goss M. J. , Howse K. R. , Vaughan-Williams Judith M. , Ward M. A. , Jenkins W.
Published: March 2009

In each of the years from September 1977 to July 1982 winter wheat was grown on one or more of three clay soil sites (clay content 35–55%) in Oxfordshire where the climate is close to the average for the area of England growing winter cereals.

The effects on crop water use of different soil management practices, including ploughing, direct drilling and subsoil drainage, are compared. Cultivation treatment had little effect on the maximum depth of water extraction, which on average in these clay soils was 1·54 m below the soil surface. Maximum soil water deficit was also little affected by cultivation; the maximum recorded value was 186±7·6 mm. Subsoil drainage increased the maximum depth of water extraction by approximately 15 cm and the maximum soil water deficit by about 17 mm.

Generally soil management had little effect on either total water use by the crop which was found to be close to the potential evaporation estimated by the method of Penman, or water use efficiency which for these crops was about 52 kg/ha par mm water used.

Results are discussed in relation to limitations to potential yield.
Combining-ability analysis in cotton for agronomic characters, fruiting efficiency, photosynthesis and bollworm resistance
Authors: Bhardwaj H. L. , Weaver J. B.
Published: March 2009

Heterosis and combining abilities for yield, bollworm resistance, fruiting efficiency and photosynthesis were studied in a five-parent diallel involving cotton (Gossypium hirsutum) strains differing in their resistance to the bollworm complex (Heliothis zea and H. virescens).Substantial magnitudes of useful heterosis (over the commercial cultivar ‘Coker 304’) were observed for yield and other agronomic characters. Useful heterosis for yield ranged from 1 to 32·7%. The highest yielding hybrid was Coker 304 × PD 695. The strain PD 695 is moderately resistant to bollworms.

All the hybrids having at least one resistant strain as their parent suffered less damage from bollworms than Coker 304. The resistant strains (BW 76–31, PD 695 andred leaf cotton) had desirable general combining ability (GCA) effects for bollworm damage. Relative yield (yield without protection expressed as percentage of yield with protection) was used as a measure of bollworm resistance. The high gossypol strain BW 76–31 had desirable GCA effects for relative yield, bollworm damage to buds, number of live worms and for bolls per plant. The fruiting efficiencies and photosynthetic rates of some bollworm-resistant strains were similar to those of a high-yielding, moderately susceptible cultivar.

Combining-ability analysis indicated BW 76–31 to be a desirable parent for use in hybridization programmes for improving agronomic performance, fruiting efficiency, photosynthetic rate and bollworm resistance. It was also observed that bollworm-resistant cottons do not always have lower fruiting efficiencies and photosynthetic rates and it might be possible to combine this resistance with high yields.
Time of Sowing and the Yield of Winter Barley
Authors: Green C. F. , Furmston D. T. , Ivins J. D.
Published: March 2009

During three growing seasons (1980–3) the influence of sowing date (early September to mid-November) on the yield of winter barley (cv. Igri) was assessed. Delaying sowing resulted in a linear decrease in maximum grain yield at a rate of 0·43 % for every day sowing was delayed. Advancing the date of sowing increased the duration of preanthesis development, increased the level of tillering and hence ear density at harvest. Yield was linearly related to the resultant higher number of grains.
Vegetative growth of winter barley in relation to environmental conditions and grain yield
Authors: Ramos J. M. , del Moral L. F. Garcia , Recalde L.
Published: March 2009

The object of this study was to investigate the vegetative growth in six barley varieties grown in southern Spain (Granada) during 1979, 1980 and 1981. The results showed that crop dry weight (CDW) was dependent on environmental factors (mean temperature, rain, and radiation) which were the determinants of the two CDW components, leaf area index (LAI) and leaf area ratio (LAR). However, the effects of these climatic factors on crop growth rate (CGR) and on its components, mean leaf area index () and net assimilation rate (NAR), were partially obscured by ontogenetic drift. In addition, a highly significant relationship was demonstrated between CDW (when the LAI reaches its maximum value) and grain yield. This suggests that the pre-anthesis period has a great influence in the determination of grain yield variation in hot, dry areas, where photosynthesis is very limited after ear emergence.
Drought resistance of hard wheat cultivars measured by a rapid chlorophyll fluorescence test
Authors: Havaux M. , Lannoye R.
Published: March 2009

Disks of hard wheat (Triticum durumDesf.) leaves subjected to rapid desiccation over 4 h showed noticeable changes in the shape of thein vivochlorophyll fluorescence induction curves. In drought-sensitive varieties (such as Claridoc), water stress resulted in a strong inhibition of the slow fluorescence induction transients. In particular, the fluorescence quenching rate was markedly decreased in water-stressed leaf disks. In contrast, leaves of drought-resistant varieties (such as Aouedj) showed only minor changes in chlorophyll fluorescence. The results of this investigation suggest that the slow transient of thein vivochlorophyll fluorescence induction phenomenon may provide a simple method for selecting drought-tolerant wheats.
The effect of rate of application of nitrogen fertilizer on soil copper uptake by barley under unirrigated conditions
Authors: Tiwari R. C. , Adinarayana J.
Published: March 2009

Field experiments were conducted on four barley cultivars (two hulled and two hullless) grown under unirrigated conditions in Varanasi, India, to observe the effect of rate of application of nitrogen on copper concentration and uptake in plants and soils. The copper concentration in both plants and soil decreased with age of crop because of the dilution effect of more vegetative growth. Varieties did not differ in copper concentration of plants but increasing application of nitrogen decreased copper concentration in the plants. Since the hulled varieties yielded more than the hull-less ones, they removed more copper from the soil. Similarly yield was increased linearly by the application of N fertilizer and this led to a linear increase in depletion of available copper.
The influence of sowing rate and row spacing on the plant density and yield of red beet
Authors: Benjamin L. R. , Sutherland R. A. , Senior D.
Published: March 2009

Three experiments examined the effects of sowing rate and between-row spacing on the plant density and yield of red beet.

The proportion of seeds which produced mature plants decreased when the mean distance to the nearest neighbour was less than 5 cm. In these experiments, this distance was governed by within-row spacing. Thus, plots with narrow-spaced rows achieved a higher plant density than those with wide-spaced rows, when sown with the same weight of seed.

Total yield of beet per unit area decreased with increasing plant density. Maximum yields per unit area of small beet were achieved at high plant densities, whereas maximum yields of large beet were achieved at low plant densities. The effect of between-row spacing on yield was much smaller than that of density, and was important only for crops harvested early. Shoot yield per unit area was measured in two experiments and was not affected by row spacing in either. Shoot yield was not affected by plant density in one experiment, but, in the other, tended to a maximum value with increasing plant density.
Observations on the vitamin metabolism of the common fowl IV. Free and combined riboflavin in the magnum and liver of the laying hen fed a diet high in riboflavin
Authors: Bolton W.
Published: March 2009

1. The partition of riboflavin into free vitamin, flavinmononucleotide and flavin-adenine-dinucleotide in the livers and magnums of laying hens fed a diet rich in riboflavin has been determined.

2. Free riboflavin in the liver amounted to 4·3% of the total vitamin, and it is concluded that this tissue does not play any part in the day-to-day metabolism of riboflavin secretion in the albumen.

3. The average amount of free riboflavin in the magnum is 45% of the total vitamin. As an egg passes through the organ, the amount decreases; this decrease is equal to the amount secreted in the albumen of the egg.

4. It is suggested that riboflavin accumulates in the blood while an egg is in the magnum, and in the magnum in the intervals between the passage of eggs, and that the riboflavin in the albumen is secreted at the same time as the albumen.
The chemical composition of the pre-sperm fraction of bull ejaculate obtained by electrical stimulation
Authors: Lutwak-Mann C. , Rowson L. B. A.
Published: March 2009

1. Semen was collected from bulls by means of the electro-ejaculation method developed by Thibaultet al.(1948).

2. A copious sperm-free fraction of the ejaculate, produced in the early phase of stimulation, was examined for its chemical composition.

3. This secretion was found to have a low protein content, but its chloride concentration was higher than in the sperm-containing fractions of the ejaculate. Fructose and citric acid occurred in very low concentrations, and 5-nucleotidase was absent in the pre-sperm secretion. This indicates clearly that the secretion does not originate either in the seminal vesicles or in the ampullar glands; it is probable that it represents a discharge from the urethral glands.

4. The effect of the pre-sperm ejaculate fraction upon bull sperm fructolysis and motility was examined; both were unaffected by a considerable excess of this secretion.

5. The chemical composition of the pre-sperm secretion makes it unlikely that under physiological conditions it could play a role in the nutrition of the spermatozoa; presumably, its chief function is the clearing of the urethral passage prior to the descent of the semen proper.
Studies on the nutrition of wool follicles in sheep: the anatomy of the general blood supply to the skin
Authors: Ryder M. L.
Published: March 2009

1. Dissections were carried out on lambs, and the skin was found to be supplied by numerous small arteries fairly evenly distributed, but often in series along the body. In several instances these arterial trunks were traced back through the body muscles to various main arteries.
The liability of seed crops of perennial ryegrass (Lolium perenne) to contamination by wind-borne pollen
Authors: Griffiths D. J.
Published: March 2009

Some aspects of intervarietal crossing in Lolium perenne have been studied.

Using a number of experimental designs with non-red plants as the tester variety, results have been obtained as to the effects of isolation distance on intervarietal crossing.

In all cases contamination decreases rapidly, at first with increasing distance, but there is a progressive reduction in the rate of decrease produced by repeated increases in isolation distance. The actual rate of decrease varies with the number and arrangement of plots.

The effect of intravarietal pollen in reducing intervarietal crossing appears similar to that of distance in its mode of action. Within short distances from the contaminant, additional rows of intervening plants are highly effective in reducing contamination. This suggests that pollination within a population of plants occurs chiefly between neighbouring plants.

The flowering periods of the different strains of Lolium perenne and L. italicum overlap to varying degrees. Several early strains flower at the same time, e.g. British commercial, New Zealand Certified Mother Seed and Station-bred S24 perennial rye-grass; others, such as Kentish indigenous perennial ryegrass and strains of L. italicum, which are intermediate in date of flowering, overlap with both the early- and late-flowering strains.

Intervarietal crossing is considerably reduced when varieties which differ widely in date- of flowering are grown in close proximity to one another, but even in the case of extreme early and late strains some spatial isolation, or discarding of border rows, is necessary for maintaining varietal purity.

In certain instances when seed crops of early-flowering strains are endangered by late-flowering plants growing in adjoining leys, satisfactory isolation may be achieved through cutting back the contaminant crop just before flowering. When seed crops of late-flowering strains are grown alongside leys containing early-contaminant varieties, cutting back should be delayed until a few days prior to commencement of flowering in the seed crop.

The practical application of the results to grass seed production has been discussed. Existent isolation requirements appear not too great for grass seed crops intended for further seed multiplication, but for commercial seed crops the spatial isolation distance generally recommended may be reduced to 100, or even 50 yd., in the case of large fields.
The value of Australian sorghum for fattening pigs
Authors: Braude R. , Mitchell K. G. , Robinson K. L.
Published: March 2009

1. At two centres, Hillsborough and Shinfield, forty-eight pigs in four groups were fattened on rations containing Australian sorghum. The control ration consisted of 30%, wheatfeed, 30% barley meal, 30% maize meal and 10% fish meal. In the three experimental rations either barley meal or maize meal or both were replaced by sorghum.

2. The rations containing 30% of sorghum proved to be equal to the control ration as far as live-weight gain of the pigs and the efficiency with which they utilized food was concerned. When 60% of the ration consisted of sorghum there were indications that both rate of gain and food utilization suffered.

3. Some aspects of carcass quality suffered when either sorghum alone or sorghum plus maize formed 60% of the ration. The quality of the control carcasses, although quite good by present-day standards, would not qualify for first grade when commercial grading is re-introduced.

4. Bacon produced on rations containing up to 60% sorghum had no off-taste or unpleasant flavour.

5. In general, the value of sorghum in the ration of fattening pigs was found to be about equal to that of maize.
The sweat glands of Ayrshire cattle
Authors: Findlay J. D. , Yang S. H.
Published: March 2009

1. An investigation has been made of the structure, distribution and dimensions of the so-called sweat glands in twenty-one different body regions of each of five 3- to 4-year-old Ayrshire cows, and incidental studies have been made on calves and embryos.

2. It has been observed that in all those regions each hair follicle is accompanied by an arrector pili muscle, a sweat gland and a sebaceous gland. This combination has been designated a ‘hair follicle unit’.

3. In the skin of embryos the sweat gland appears as a single unbranched tube and in the skin of calves and cows it is a bag-shaped gland with a long slender duct which opens on the skin surface as a funnel-shaped outlet.

4. The gland is composed of two layers of cells, an outer myoepithelium and inner glandular epi thelium.

5. What may be successive stages in the intraluminal transformation of the secretory products discharged by the gland cells lining the lumen, are illustrated by a series of photographs.

6. The glands have a poor blood supply and appear to be apocrine. It is unlikely, therefore, that the sweat glands of Ayrshire cows function as effectively in heat regulation as human sweat glands.

7. The number of sweat glands per sq.cm. of skin was measured in all the regions. The average number was 1871 per sq.cm., ranging from about 1000 in the lower limbs to about 2500 in the axilla and neck regions.

8. The length and circumference of the gland were measured, hence its secretory surface was calculated. The average area of secretory surface of a single sweat gland was 0·22 sq.mm., while the average area of secretory surface of the sweat glands per sq.cm. of skin was 3·94 sq.cm. There was a significant negative correlation between the number of glands per sq.cm. and the area of secretory surface of a single sweat gland.

9. The ventral region of the neck, the axilla and upper hindleg had the largest area of secretory surface per sq.cm. of skin, while the forehead, back (sacral), gluteus, lower foreleg and hindleg had the smallest.

10. The only region which had a significantly smaller area of secreting surface than the front flank region was the sacral region of the back.
Confidence limits of expected monthly rainfall
Authors: Manning H. L.
Published: March 2009

Precise confidence limits of expected monthly rainfall must be regarded as fundamental to the specification of the climatic regions of an agricultural region. The science of weather forecasting is necessarily based on extensive statistics of past experience. However, unless account is taken of such factors as skewness, the means and standard deviations calculated from such statistics will lack the necessary precision and may often be misleading.

This paper shows that frequency distributions of monthly rainfall, which were demonstrably skew, may be suitably transformed so that on the new scale they approximate closely to theoretical normal distributions. As a result precise fiducial or confidence limits—shown in fact to fit the data satisfactorily—may be estimated and afterwards reconverted to the original units.

Practical applications of these confidence limits include the more accurate representation of rainfall patterns, valuable guides to the vital question of optimum time of planting, and finally, better estimates of the range of mean monthly rainfall where data are available only from a limited number of years.

Application of these limits to some special cases is discussed in some detail.