bluuebunny/crossref_metadata_2025 huggingface dataset:
Carcass characteristics of indigenous breeds of cattle in Nigeria
Authors: Buvanendran V. , Ikhatua U. J. , Abubakar B. Y. , Olayiwole M. B.
Published: March 2009

Bunaji and Sokoto Gudali breeds of cattle were fattened and slaughtered at live weights of 250, 300 or 350 kg. After the carcasses were jointed into commercial cuts, the joints of the left side were dissected into lean, bone and fat. Dressing percentage was significantly higher in Bunaji carcasses (52·5%) than in Sokoto Gudali carcasses (50·3%). The lean percentage was nearly constant at 68·69% at all slaughter weights whereas fat percentage increased from 10·3 at 250 kg to 14·5 at 350 kg. Bone percentage was inversely related to fat percentage. The relative growth coefficients of muscle and fat were 1·28 and 1·80, whereas that of bone was 0·59. Significant changes in proportion of carcass parts and tissues were observed with increased slaughter weight. The proportion of hind decreased and that of back and belly increased, while chuck and shank remained relatively unchanged. Lean percentage was relatively unchanged by slaughter weight in all carcass parts except the chuck where it increased. The greatest increase in fat percentage was in the belly (7·6%) followed in decreasing order by the back (5·4%), shank (4·9%), hind (3·0%) and chuck (1·8%). The breeds did not differ in any of the traits except dressing percentage.
The copper content of wool in relation to breed and the concentrations of copper in the liver and plasma
Authors: Woolliams J. A. , Wiener G. , Suttle N. F. , Field A. C.
Published: March 2009

Little reliable information is available on the range and variability of the copper content of the wool of sheep (Underwood, 1977), although the effect of Cu deficiency on keratinization and pigmentation of wool is well known (Ryder & Stephenson, 1968) and the Cu content of hair has been suggested as a possible aid in diagnosis of hypocuprosis. Results from Kellaway, Sitorus & Leibholz (1978) showed that, in cattle, Cu in hair and plasma decreased in animals when the concentration of Cu in the liver fell below 20 mg/kg D.M. An experiment carried out jointly by the Animal Breeding Research Organisation and the Animal Diseases Research Association to investigate breed differences in the long-term accumulation of Cu in sheep gave an opportunity to investigate both the range of Cu concentrations in wool and the relationship between the Cu content of the liver and wool Cu.
Stem borer damage in maize as affected by host plant density
Authors: Ogunwolu E. O. , Nwosu K. , Ogunyebi S. O.
Published: March 2009

Maize grain production in Nigeria is the collective effort of several growers individually cropping small areas. In these farms, maize stands are at suboptimal densities, soil fertility is low and crop loss from pests is high. Consequently, grain yields are characteristically low. By planting maize at closer spacing than the current standard, 90 x 25 cm, Fayemi (1963), Chinwuba (1967), and Okigbo (1972) were able to raise grain yield. However, the effect on pest population in Nigeria of increasing host plant density has received little research attention. Cromartie (1975) showed that host plant density and arrangement affect insect population dynamics. Other reports by Ficht (1932), Finch & Skinner (1976), Ralph (1977), Zepp & Keaster (1977), Adesiyun (1978) and Mayse (1978) indicate differential insect colonization, establishment and damage on host plants sown at different densities.
The effect of different degrees of food restriction in late pregnancy on nitrogen metabolism in ewes
Authors: Espinosa R. Valdez , Robinson J. J. , Scott D.
Published: March 2009

Nine individually penned Finnish Landrace x Dorset Horn ewes with a mean litter size of 2·33 were offered a diet containing 63% digestible organic matter (DOM) and 13% crude protein in the dry matter at a daily intake of 0·82 kg DOM (1·3 x maternal maintenance) from 95 to 110 days of gestation. On day 111 DOMI was abruptly reduced to either 0·67 kg (T1, 0·54 kg (T2) or 0·36 kg (T3)/day and kept at these levels until a few days pre-partum.

Daily N balance before food restriction was 4·9 ± 0·51 g/day. During the periods 3·9 (S1), 11·17 (S2) and 19·25 (S3) days after food restriction daily N balance was 2·8, 2·8 and 3·6 g for θwes on T1, 1·0,1·0 and 0·8 g for those on T2 and –4·1, -4·0and -4·0 g for those on T3. Total lamb birth weight was 8·0, 7·2 and 6·5 kg for treatments T1, T2 and T3 respectively. Using regression analysis it was calculated that plasma glucose concentration in late pregnancy for ewes with a total lamb birth weight of 8 kg fell below the pre-restriction value of 52 mg/100 ml when daily DOMI was reduced to 747 g. At this intake the plasma FFA concentration was 585/i-equiv./I compared with 288 before food restriction. Corresponding values for daily N balance were 5·1 and 4·9 g. A reduction in daily energy intake below 0·75 kg DOM resulted in a rapid decrease in plasma glucose and N balance, the latter being proportional to the increase in the concentration of plasma FFA. The mean daily loss of N from the maternal body was estimated to be 0·4, 1·6 and 6·1 g for treatments T1 to T3 respectively during the period of food restriction.
Competition studies in diploid and tetraploid varieties of Lolium perenne: 2. The inhibition of germination
Authors: Harries J. H. , Norrington-Davies J.
Published: March 2009

Seed extracts prepared by soaking ryegrass seed in water were tested for their ability to suppress germination. The tests were carried out by sowing seed on to sand-filled basins moistened with seed extract.

Extracts prepared from the two diploid varieties, S. 24 and Hora and the tetraploid variety Terhoy were able to reduce both the rate of germination and the final percentage germination when applied to the sown seed. The details were as follows, (i) When S. 24 perennial ryegrass seed was used to obtain the extract inhibition was found to be related to the concentration of the extract, (ii) The final germination of diploid seed was reduced by 16% in the presence of its own seed extract and by 27% when tetraploid seed extract was applied, (iii) The final germination percentage of the tetraploid seed was reduced by 14% in the presence of either its own extract or that prepared from the diploid seed, (iv) Simple chemical tests carried out on the seed extract, although not conclusive, gave some indication that the inhibitory substance may have been a member of the alkaloid group.
The effect of soil type and related factors on sugar beet yield
Authors: Webster R. , Hodge C. A. H. , Draycott A. P. , Durrant M. J.
Published: March 2009

Yields of sugar and responses to fertilizers were determined in about 400 fertilizer experiments on farms throughout the sugar-beet growing areas of Britain during 14 years from 1957 to 1970. The soil at each experimental site was described and classified and the records of the experiments have been examined to determine which properties of the soil influence sugar yield. The effect of year, rainfall, elevation, region and other factors such as sowing and harvesting date were also investigated.

Year-to-year variation accounted for 20 % of all variation in yield; increasing amounts of rainfall during the growing season appeared to decrease yield. There was a significant long-term trend of increasing sugar yield from the experiments of 0·042 t/ha/year. The experimental yields closely followed national yields each year but were always greater. Delay in sowing and early harvesting depressed yield by 0–02 and 0·01 t sugar/ ha/day respectively. Yields in Scotland (average 5·23 t/ha) were approximately 1·4 t/ha less than in England and Wales, but there were no evident regional differences within England and Wales.

Soil regarded as moderately drained yielded better than either well-drained or imperfectly drained soil, which in turn yielded better than droughty and poorly drained soil. The difference in the adjusted yield between drainage classes was 1·0 t/ha. Surprisingly, topsoil texture had no consistent effect on mean yield (as distinct from response to fertilizer). Subsoil texture, however, had an appreciable effect, the crop on sandy subsoil and chalk or limestone yielding poorly whilst that on silt or peat yielded best. The range of differences in sugar yield due to subsoil texture was almost 2 t/ha.

Yields were also examined in relation to soil profile type. Broad division into major soil groups gave meaningful differences but fine division by soil series was only useful for the 11 series on which at least ten experiments had been made. The crop yielded most sugar on gleyed calcareous soils, peats and humic gleys, and least on rendzinas and brown calcareous soils. Responses to nitrogen and potassium but not to phosphorus were affected by both topsoil and subsoil texture. Nitrogen and potassium both increased yield most on sandy soils and least on fine silts and peats.

The morphology, chemical and physical condition of soil clearly affect sugar yield greatly and further research is needed in experiments planned specifically to measure their influence and provide more precise guidance for selecting the best land for the crop.
The Effect Of Grazing Compared With Cutting, at Different Frequencies, On a Lucerne-Cocksfoot Ley
Authors: Wilman D.
Published: March 2009

Grazing with sheep was compared with cutting, in each case at three frequencies, four, five and six defoliations per year, on a lucerne—cocksfoot ley. The treatments were applied in one year and their effects measured during that year and at cuts in June and August of the following year. One experiment began in 1963 in the second harvest year of a ley and a second began in 1964, on an adjacent site, in the third harvest year of the ley. Cutting four times in the year allowed lucerne to persist satisfactorily in both experiments. In the 1964 experiment cutting five or six times and grazing rather than cutting had no apparent, serious, adverse effect on the lucerne compared with cutting four times. In the 1963 experiment, however, increasing the number of cuts and grazing rather than cutting had a large adverse effect on the lucerne, and in the most extreme treatment, grazing six times, the proportion of lucerne was reduced to 2 % of total herbage yield the following June compared with 66% on the four-cut treatment. The contrasting results in the two experiments seem associated with weather differences, 1964 being a much drier, more sunny growing season than 1963, and perhaps with the differences in age of sward, individual lucerne plants perhaps having bigger roots with more reserves in 1964 than in 1963. During the treatment year increasing frequency of defoliation tended to increase the N content of both species and grazing compared with cutting generally increased the N content of cocksfoot. During the year following the treatment year the N content of the two species was little affected by the experimental treatments. The implications for farm practice are considered.
Soil characteristics and nutrient indexing of vineyards in Punjab, India
Authors: Arora C. L. , Hundal H. S. , Takkar P. N.
Published: March 2009

A survey of 46 vineyards was conducted to determine whether some nutritional disorder was the cause of declining yields. The surface soils, in general, are alkaline, calcareous, medium to high in organic matter, light in texture and sufficient in available micronutrients except B. Petiole analysis indicated a deficiency of Zn, Fe, Mn, B and Cu in 70, 52, 37, 20 and 13% as well as an excess of P and K in 35 and 93% of the vineyards respectively.

Significant negative correlations of P with Fe and Mn and that of K with Zn showed that the lack of Fe, Mn and Zn might have been induced by excessive application of P and K fertilizers. Poor correlations between the DTPA-soluble concentrations of Cu, Fe, Mn and B in the soils and those in the petioles suggested the nutrient status of surface soils to be of little value in the nutrition of grape vines or that the petiole may not be the best tissue for this purpose.
Effect of sowing date and soil type on plant survival and grain yield of chick peas (Cicer arietinum L.)
Authors: Ageeb O. A. A. , Ayoub A. T.
Published: March 2009

Sowing date directly affected the grain yield of chick peas. Optimum sowing date was found to be between the end of October and the end of November, but different soil types showed some differences within this optimum.

Grain yield was highly correlated with number of pods per plant and number of plants at harvest.

Plant loss at the seedling stage was highly correlated with daily mean maximum air temperature, and was also significantly associated with sodium accumulation in shoots.
Intake and utilization of food by growing sheep with abomasal damage caused by daily dosing with Ostertagia circumcincta larvae
Authors: Sykes A. R. , Coop R. L.
Published: March 2009

Four groups of eight sheep, 4 months of age and reared parasite-free from birth, were used to investigate the effect of the abomasal parasite Ostertagia circumcincta on the intake and efficiency of utilization of food. One group (CI) was killed initially as control. Two further groups (ALC and ALI) were offered ad libitum a complete ruminant diet. The ALI group was dosed daily for 14 weeks with 4000 infective larvae. Sheep in a further group (PF) were individually paired to members of the ALI group and offered the same amount of food as was consumed by their pair. Balances of N, Ca and P, and the digestibility of energy and N were determined for the ALI and PF groups during weeks 2–3, 7–8 and 12–13. After 14 weeks of dosing the sheep were killed and the bodies of these and the CI sheep analysed for water, fat, N, Ca and P contents.

Parasitism caused a 20% reduction of food intake by week 2 which was maintained throughout the experiment. Apparent digestibility of nitrogen was reduced from 60 to 44% at weeks 2—3 but subsequently showed a gradual recovery. Nitrogen balances of infected sheep were inferior to those of controls which, with the exception of the first trial during which urinary N excretion of infected sheep was increased, was entirely related to the reduced digestibility. Energy digestibility was reduced by 2 percentage units during all trials.

Weight gain of ALI sheep was only 80% of that of PF sheep. Nitrogen anabolism was reduced by parasitism, but pair-feeding showed that reduced food intake rather than a specific effect on protein metabolism was responsible. Fat deposition was markedly reduced. It was calculated that the gross efficiency of utilization of metabolizable energy for growth was reduced by 30% compared with either ALC or PF controls.

Mineral deposition (Ca or P) in the skeleton of the ALI sheep was reduced to about 35 and 50% of that in ALC and PF groups, respectively.
Oil content of cotton seed in Northern Nigeria: 2. varietal and environmental variation
Authors: Gridley H. E. , Smithson J. B.
Published: March 2009

Differences between sites accounted for a large proportion of the variation in the oil percentage of cotton seed from variety and agronomic trials conducted in Northern Nigeria but were not consistent between seasons. Reduced oil percentages from the drier areas of the north and from later sowings suggested that length of season is an important factor but insect attack and differences in the amounts of nitrogen, potash and boron applied to the soil also contributed to the variation. Application of insecticide, potash and boron increased and nitrogen decreased oil percentages. The latter effect usually resulted from an increase in seed size without a corresponding increase in oil content. The variation in the oil percentages of commercial varieties derived from the same Nigerian Allen stock and the relatively small interactions between varieties and environments suggested that this character might be improved by selection.
Effect of varying the time of the first harvest, and of late planting, on double-harvest yield of yam (Dioscorea rotundata) in field plots
Authors: Onwueme I. C.
Published: March 2009

Setts of white yam (cv. Ogojo) each weighing 225 g were planted in mid·February. They were double-harvested, first in early August, early September or early October, and second in early November. The control was single-harvested in early November. The later the time of the first harvest, the greater the first-harvest yield and the higher the percentage of mature and marketable tubers. Delaying the first harvest, however, led to decreasing yields from the second harvest. Double harvesting never gave a significantly higher yield than that obtained from a single harvest. When the first harvest was taken in September, the combined yield from double harvesting was significantly lower than that of the single November harvest. In a study of the effect of sowing date on yield, late planting (April) resulted in lower first harvest and total yields than early (February) planting, but the second-harvest yield was the same. Supplementary watering of early yam plantings did not markedly accelerate emergence or increase yield.
Phosphorus status of the Nigerian coastal plain sands
Authors: Udo E. J. , Dambo V. I.
Published: March 2009

The phosphorus status of five Nigerian coastal plain sands was evaluated by determining the relative abundance of the various P forms and the P adsorption capacities of the soils. Total P ranged from 4460 to 1129 mg/kg. Organic P had a range of 23–232 mg/kg and formed below 30% of total P in four of the profiles but above 50% in the hydromorphic Otegbo profile. The relative distribution of the various inorganic forms was in the increasing order of residual P, active P and occluded P, except in the Onne profile in which the residual P was relatively the least abundant. The relative distribution of the active P forms was in the decreasing order of Fe-P, Al-P and Ca-P.

The adsorption capacity varied widely among the soils. The amount adsorbed from the addition of 150 mg/100 g of soil ranged from 40–2 to 86–2 mg/100 g and was related to the clay content. The adsorption at 0–3 mg/1 P in equilibrium solution ranged from 19 to 265 mg/kg. The subsoils generally adsorbed more P than the surface soils. The P requirements of the soils estimated from the sorption capacities were in the low and medium ranges.
The growth and development of cowpeas (Vigna unguiculata) under tropical field conditions: 1. Leaf area
Authors: Littleton E. J. , Dennett M. D. , Elston J. , Monteith J. L.
Published: March 2009

The pattern of leaf growth and death was followed in stands of cowpea grown in the field at Ibadan, Nigeria. Temperature affected this pattern. Leaf area index increased quicker and leaf death started sooner during warm seasons. Individual leaves died while pods at the same node were filling. The rate of leaf appearance increased with temperature and the duration of expansion of individual leaves decreased so that a constant number of leaves were expanding at one time. The mean rate of expansion of individual leaves increased with temperature proportionately more than the duration decreased, hence final leaf size increased with temperature. Base temperatures for leaf appearance and leaf expansion were 16 and 20 °C respectively.
Influence of temperature on growth and nitrogen fixation in cultivars of Phaseolus vulgaris L., inoculated with Rhizobium
Authors: Graham P. H.
Published: March 2009

Growth and nitrogen fixation of three cultivars of Phaseolus vulgaris L., inoculated with strain CIAT 161 of R. phaseoli, were compared at day-night temperatures of 36–25, 30–20 and 26–15 °C.

Temperature affected the duration and magnitude of N2 (C2H2) fixation. Maximum fixation increased from 33·8 μmol C2H4 produced/plant/h at 35–25 °C to 73·0 μmol C2H4 produced/plant/h at 25–15 °C, but the peak in fixation was increasingly delayed as growth temperature was reduced. In the 25–15 °C treatment this delay in the onset of fixation led to decreasing leaf nitrogen concentrations and visible N-deficiency symptoms at the 28 day harvest.

Varietal differences in response to temperature were not marked, though one cultivar achieved greater nodule development at 35–25 °C than the others. This earlyflowering cultivar again appeared weak in N2 (C2H2) fixation with low specific nodule activity at all temperatures studied.

Results are related to bean production in Latin America, and to the possible need for ‘starter’ nitrogen in the cooler bean-producing regions.
Nutrient relations of winter wheat: 1. Accumulation and distribution of Na, K, Ca, Mg, P, S and N
Authors: Gregory P. J. , Crawford D. V. , McGowan M.
Published: March 2009

Maris Huntsman winter wheat was sown on 30 October 1974 and grown under typical farming conditions. Between sowing and harvest (5 August 1975), the crop was sampled on 23 occasions and dried samples of individual plant components were analysed for Na, K, Ca, Mg, P, S and N composition.

The concentration of nutrients within the whole plant generally decreased throughout growth but different parts of the plant varied in their behaviour. Uptake of all nutrients ceased at, or shortly after, anthesis in mid-June while dry-matter accumulation continued slowly for a further 2–3 weeks and almost stopped 4 weeks before harvest. The major period of nutrient uptake occurred between mid-April and mid June coincident with the period of rapid shoot growth. Large amounts of potassium and sulphur (almost 50% of the plant's anthesis content) and lesser amounts of calcium (15%) were lost from the plant after anthesis and efflux from the roots into the soil appeared to be the most likely pathway of removal.

Accumulation of nutrients in the ear occurred throughout grain-filling by translocation from other parts of the plant, particularly the leaves and stems: the effects of this redistribution on the production of dry matter after anthesis are discussed.
Studies on lucerne and lucerne-grass leys. I. Summer and autumn management of a lucerne-grass mixture grown on heavy land
Authors: Barker M. G. , Hanley F. , Ridgman W. J.
Published: March 2009

1. Some earlier work concerning the management of lucerne is discussed.

2. Two experiments, designed to compare cutting and grazing the second (July) crop, and cutting and grazing the third crop at two different dates (September and October) each year on the yield and botanical composition of a lucerne-grass (mainly cocksfoot) ley, are described and the results discussed.

3. The method of defoliating both the second and the third crops had very little lasting effect on yield or composition of the ley, though some temporary effects, depending on season, were found.

4. It is shown that date of defoliating the third (autumn) crop of a lucerne-grass mixture may influence the yield of oven-dried produce from an individual crop. Late autumn defoliation led to a greater yield of lucerne and a greater proportion of lucerne in the produce, but since the opposite effect was found in the yield of grass there was no overall effect on the total yield of oven-dried produce over a 3-year period.

5. In these experiments it appeared that lack of winter cover had no adverse effect on the productivity or persistence of lucerne in the lucerne-grass mixture studied.
Rotation experiment in Brazil
Authors: Stevens W. L.
Published: March 2009

The design and analysis of rotation experiments present problems which are not encountered in annual experiments. The problems of design have been discussed by Yates (1949) and Stevens (1951 b). This paper is concerned with problems of statistical analysis. The experiment described is sufficiently general in its design for it to serve usefully as a basis of discussion of methods of analysis, both of the mean yields and of the measures of secular trend. It is shown that rotation experiments, without replicates within series, can be adequately analysed.
Effect of environmental temperature on suckling pigs and a study of the milk yield of the sow
Authors: Gill J. C. , Thomson W.
Published: March 2009

1. A study was made of the performance of eight litters of pigs housed under two widely different levels of ambient temperature during the suckling period and under uniform conditions from weaning to 200 lb. live weight.

2. There was no significant treatment difference in the amount of milk suckled, but the pigs exposed to the lower temperature consumed more solid food before weaning.

3. Up to weaning those kept at the higher temperature were the more efficient converters of milk and solid food into live weight.

4. There was a highly significant correlation between milk suckled and live-weight gain.

5. Probably through excessive handling, the pigs were under weight at weaning, but the postweaning performance appeared to be unaffected by the pre-weaning treatment.

6. The average milk yield of six sows from the 3rd to the 56th day of lactation was 275 kg. 605 lb.) (variations 202–347 kg. (445–764 lb.)). Yields have been compared with others published.

7. After allowing for maintenance requirements and weight gain or loss it is estimated that the sows required 412 Calories of net energy to produce 1 lb. of milk.
Influence of partial defoliation on dry-matter production and seed yield of urd bean (Vigna mungo L. Hepper)
Authors: Pandey R. K. , Singh V. B.
Published: March 2009

Field investigations were carried out to study the effect of partial defoliation on dry-matter production and seed yield of urd bean. Partial defoliation during the vegetative and/or reproductive phase reduced seed yield. The severity of yield reduction was dependent on the stage of crop development and the degree of defoliation. The reduction of total dry-matter production by defoliation was accompanied by a decrease in crop growth rate and leaf/plant weight ratio. The net assimilation rate was higher in defoliated plants from 40 to 60 days after sowing. The reduction in seed yield due to defoliation was highly due to a reduction in the number of pods per plant, and also sometimes in the number of seeds per pod and in 100-seed weight.
A note on kidney weight in Large White pigs reared in the humid tropics of southern Nigeria
Authors: Alaku O. , Steinbachf J.
Published: March 2009

Various species of animals, ranging from ordinary laboratory rats to some high-grade beef and dairy cattle, have been imported from the temperate regions of the world to Nigeria in recent years. Most favoured are Large White pigs and this breed of livestock is proving to have very great potential in the livestock production industry in this part of the tropics. Temperate breeds of livestock when introduced to the tropics are said to decline in their general performance, owing partly to direct effects of high ambient temperatures(Yousef & Johnson, 1965). Some generalized statements have also been made on the adverse effects of tropical climate on growth though very little objective field experimental evidence exists (Williamson & Payne, 1978).
The effect of three levels of intake of Ostertagia Circumcincta Larvae on growth rate, food intake and body composition of growing lambs
Authors: Coop R. L. , Sykes A. R. , Angus K. W.
Published: March 2009

Forty-eight 4-month-old lambs, reared worm-free from birth, were allocated to six groups and offered ad libitum a complete diet containing 139 g crude protein/kg D.M. One group was killed at the outset as initial control (CI). Further groups, ALC, 1, 2, 3 and 4 were dosed daily for 84 days with zero, 1000, 3000, 5000 and 5000 larvae of Ostertagia circumcincta, respectively. Lambs in group 4 also received anthelmintic (fenbendazole, 5 mg/kg) on days 21, 42, 63 and 84. Lambs were killed after 98 days and their carcasses and those of the initial controls analysed for fat, protein and mineral contents.
The effects of phosphate and soil moisture on the nodulation and growth of Phaseolus vulgaris
Authors: Bonetti R. , Montanheiro Maria Nazareth S. , Saito Siu M. T.
Published: March 2009

An examination of the effects of adding phosphorus to the soil on nodulation and P utilization in Phaseolus vulgaris L. showed a positive response in plant weight to increasing rates of phosphorus (32P) when water tension was low in the pots.

The efficiency of the utilization of fertilizer-P was directly influenced by the water content of the soil, showing increasing P accumulation after flowering.

A highly positive interaction between P addition, water content and nodulation was observed. Nodules were shown to have a high P requirement, with phosphorus (32P) contributing to an increase in the number and size of nodules.
Fungicide effects on light leaf spot, canker, crop growth and yield of winter oil-seed rape
Authors: Rawlinson C. J. , Muthyalu G. , Cayley G. R.
Published: March 2009

Field experiments with rape ovs Primor, Jet Neuf and Norli during 1979–83 tested the effects of benomyl, prochloraz, imazalil, thiabendazole, metalaxyl or triadimefon sprays applied at different times on disease, crop growth and yield. The principal disease in all experiments was light leaf spot (Pyrenopeziza brassicae).

A single spray in autumn of benomyl or prochloraz at 0·5 kg a.i./ha consistently decreased incidence and severity of light leaf spot and sometimes decreased stem canker (Leptosphaeria macvlans). Under severe disease conditions in cv. Primor an autumn spray of fungicide contributed more to disease control than a spray in spring; a decrease in light leaf spot incidence was detectable up to 8 months after application. The autumn spray maintained plant population density, increased leaf area index, dry matter, crop growth rate, earliness of flowering, and yield by up to 0·69 t/ha; an autumn + spring spray increased yield by up to 0–83 t/ha. Effects on crop growth and yield were due to disease control not direct chemical stimulation of growth. Measurements of crop growth and population per unit area revealed the effects of fungicides more clearly than traditional disease assessments based solely on randomly selected plants.

Triadimefon sprayed on rape stubble at high dose rate (1 kg a.i./ha) decreased incidence and severity of light leaf spot throughout the growing season of a subsequent rape crop, with beneficial effects on plant population density, growth, flowering and yield.

Electrostatically charged rotary atomizer and conventional hydraulic spray applications of fungicide were equally effective in disease control. A reduction to one quarter in dose rate of prochloraz and 100–fold reduction in amount of water carrier (125 g a.i. in 4·3 1/ha) when applied electrostatically in autumn or autumn + spring had similar effects on disease, crop growth and yield to those obtained with a conventional sprayer delivering 500 g a.i. prochloraz in 410 1/ha.

Fungicides, spray timing and methods of application are discussed in relation to the epidemiology of light leaf spot and canker and the economics of disease control.
A stochastic model of the reproductive performance of dairy herds
Authors: Morant S. V.
Published: March 2009

A model of reproductive performance in dairy herds is described. The model relies upon no empirical relationships but is constructed from a series of simple stochastic processes involving only three principal parameters: ovulation detection rate, pregnancy rate and embryo loss rate. The model shows how the complex interactions between these parameters and management policy concerning the definition of the service period are generated.
The effect of delayed harvest and leaching on the morphine concentration of poppy (Papaver somniferum L.) capsules
Authors: Laughlin J. C.
Published: March 2009

In a series of field experiments over four seasons, in the north-west region of Tasmania, poppy (Papaver somniferum L.) capsules were harvested at various intervals after dry maturity (12% moisture in capsules). Reductions in the relative morphine concentration of capsules were closely associated with rainfall after dry maturity. These values ranged from a reduction of 0·92 to 0·82% over 5 weeks with 13 mm of rain to a reduction of 0·95 to 0·31% over 6 weeks with 79 mm of rain.

In a simulated leaching experiment ground capsules were leached with 50 mm of water. Morphine was detected in the leachate and after being held for 10 days the morphine concentration of the ground capsules had decreased from 0·56 to 0·22%.

Intact capsules from glasshouse grown plants were harvested at 2 weeks (T1, 4 weeks (T2), and 6 weeks (dry maturity T3) after full bloom. At each time of harvest they were immersed in distilled water for four different lengths of immersion time: zero (L0), 6·7 min (L1, 44·8 min (L2), and 300 min (L3). After immersion both the immersion water and the capsules were analysed for morphine. Morphine was readily detected in the immersion water with more at T3 than T2 and the amount of morphine increased as the length of immersion time increased. This latter process was greater at T3 than T2. At both T2 and T3 here was a trend for capsule morphine to decrease as immersion time increased.
Milking at three eight-hour intervals as a means of investigating variations in the fat and solids-not-fat
Authors: Campbell K. W. D.
Published: March 2009

It has been shown that in this trial the increase in milk yield of the nine cows considered as a herd is within the limits normally expected in the case of thrice-daily milking.

The increase in the case of the heifers is below expectation, and the probable reasons for this are indicated.

The effect of three 8-hour intervals on butter-fat percentage has been studied, and it is shown that as far as the individual cows are concerned there is little difference between the number of low fats produced under thrice milking at equal intervals and twice milking at unequal intervals in the case of the herds specified. It is shown that the reason for the bulk milk of the thrice-milked cattle maintaining a high standard of fat percentage at each milking is that each individual cow maintains a fairly high level consistently at one specific milking, and that this is not the same milking for each cow.
Migration of pedigree Ayrshire cattle in Great Britain
Authors: Wiener G.
Published: March 2009

Migration of pedigree Ayrshire cattle in the British Isles is estimated for 1927 and 1946 from samples of herd-book registrations. Most migration is from Scotland, particularly Ayrshire, to England, but considerable numbers were also transferred between regions within Scotland or England. A larger proportion of bulls than of cows was moved in this way. Only a small proportion of animals had two parents bred in the same herd as themselves. If the males and females registered from England in 1946 were the sole parents of the next generation, the latter would still have more than half Scottish blood.

The amount of movement of Ayrshire cattle shown by these data virtually precludes genetic differences between regions, but not perhaps between herds. Other implications of movement are discussed.
American hybrid maize for silage in the south of England Part I. The yield and composition with special reference to plant population and nitrogenous fertilizer
Authors: Castle M. E. , Foot A. S. , Rowland S. J.
Published: March 2009

For three consecutive years American hybrid maize was grown, under replicated experimental conditions, in the south of England. Each season, the influence of the spacing of the plants and the use of nitrogenous fertilizer on the yield and composition of the crop and of its separate portions of leaf, stem and cob was investigated.

The growth of the maize, and especially its yield of dry matter, were influenced by the weather conditions during the season. The weight of fresh crop varied, with season and treatment, from 126 to 278 (averaging 209), and of dry matter from 20 to 70 (averaging 50) cwt./acre.

Thinning below the established plant populations of up to 30,000 plants per acre regularly reduced these yields. Top-dressing with sulphate of ammonia increased them in 1947 and 1949, but decreased them in 1948.

The yield of crude protein varied from 2.2 to 5.0, and of soluble carbohydrates from 12 to 46 cwt./acre. The top-dressing increased the protein content of all portions of the plant.

The cob contributed, on a weight basis, 46% of the fresh crop, 49% of its dry matter, 54% of its crude protein and 54% of its soluble carbohydrates. Details are given of the chemical composition of the whole plant, and of its separate leaf, cob and stem, for each season and treatment.

A later paper will deal with the making of silage from the maize crops and with the yield, composition and nutritive value of the silage.
Composition of beef carcasses:II. The use of regression equations to estimate total tissue components from observations on intact and quartered sides and partial dissection data
Authors: Williams D. R. , Pomeroy R. W. , Harries J. M. , Ryan P. O.
Published: March 2009

The data described in Part I of this series (Pomeroy et al. 1974) were analysed by regression methods, to see how, and how well, estimation of total carcass composition (simplified to bone, lean and fat) can be achieved in situations where the beef side cannot be fully dissected, but can be measured as an intact side, quartered and the cut surface photographed, or where sample joints can be dissected. Equations are given, based on the largest group (Group II, 72 animals) of the three previously described, and the advantages to be gained from quartering the carcass, photographing the cut surface, and dissecting a sample joint are quantified. These equations have been tested by applying them to the other two groups, I and III of 30 and 43 animals.
The efficiency of seedling selection by visual preference in a potato breeding programme
Authors: Brown J. , Caligari P. D. S. , Mackay G. R. , Swan G. E. L.
Published: March 2009

The efficiency of visual selection in a glasshouse of 1600 seedlings compared with visual selection in the field of the same clones is examined. Also the amount of agreement in assessment between four different potato breeders screening the same clones is investigated. Seedlings were grown from true seed in four-inch pots in a glasshouse and all the clones which produced tubers were grown in the field the following year. Clones which produced more than one tuber from a seedling were grown at two locations in the first clonal year. One of the sites used in the first clonal year is normally used for potato yield trials (i.e. a ware site) and the other is normally used for the production of healthy seed tubers (i.e. a seed site). In all three environments, the tubers produced from each plant were assessed by four breeders independently on a 1–9 scale of increasing attractiveness.

From the data it was found that the repeatability of assessment between the glasshouse and the first clonal year was low in that the correlation between the average preference score of the four breeders in the glasshouse and each of the two first clonal year sites accounted for only 8·24 and 6·84% of the total variation. Many clones which had low scores in the glasshouse were subsequently given high scores in the first clonal year. It was therefore concluded that selection of seedlings was not very efficient. Although, in general, the weight of the tuber that was planted greatly influenced whether a clone was selected in the first clonal year, a large number of clones which produced only small tubers in the glasshouse were subsequently selected in the first clonal year.

Within each environment the four breeders were either all selecting, or all rejecting, a much higher proportion of clones than would be expected if selection had been made completely at random. The breeders were in most agreement when assessing clones at the ‘ware’ site, and in most disagreement when assessing them grown in the glasshouse from true seed. Therefore the poor efficiency of selection of seedlings grown in the glasshouse was not, in the main, a result of a high error variance in visual assessment but rather due to poor association between the performance of seedlings and first clonal year plants.
The concentrations of air-borne rape pollen over a crop of oil-seed rape (Brassica napus L.)
Authors: Williams Ingrid H.
Published: March 2009

The air over a crop of flowering winter oil-seed rape was sampled for 39 days with an automatic volumetric spore trap. Considerable quantities of rape pollen were caught on most days. Density of pollen showed marked diel periodicity; few grains were caught at night and at mid-day, peaks occurred in late morning and early afternoon. It is concluded that wind plays a considerable role in pollination of the crop.
Effects of fertilizer on root growth and water use of barley in northern Syria
Authors: Gregory P. J. , Shepherd K. D. , Cooper P. J.
Published: March 2009

Barley (cv. Beecher) was grown at two sites (Jindiress and Breda) in northern Syria, chosen for their contrasting edaphic and climatic conditions. At both sites, three fertilizer treatments were applied zero (Z), 60 kg P2O5/ha (P), and 60 kg P2O5/ha with 60 kg N/ha (NP) and measurements made of shoot and root growth, and water use.

The growth of crops not given fertilizer was similar at both sites and early growth was increased by the application of fertilizers. However, at maturity, yield was increased at Jindiress by giving N and P together, but not by P alone, while at Breda P alone increased yields but additional N produced no additional yield. There were marked effects of fertilizer on crop development at Jindiress; anthesis and maturity were about 14 days earlier in the NP treatment than in the Z treatment.

Root growth was also affected by fertilizer applications and there were small but significant differences in growth between the sites. The proportion of root weight: total plant weight was greater than commonly observed in temperate cereals and there were substantial differences between the sites in the pattern of root distribution within the soil profile.

The total amount of water used by the crops differed between the sites but was largely unaffected by fertilizer treatment at each site. Evapotranspiration during the winter when the soil was recharged with water was about 50% of the seasonal total. At Jindiress, the pattern of water extraction from the profile and the root distribution were similar before flowering but at Breda, there was no correspondence. Rates of water inflow varied with both site and time.

Crop characteristics that may be associated with increased yields are discussed. Deeper, more extensive rooting is unlikely to be useful in such regions but rapid early growth of both shoots and roots may allow water to be used more efficiently.
Growth and development in the pig, with special reference to carcass quality characters. I
Authors: McMeekan C. P.
Published: March 2009

1. With the object of establishing the general order of development during post-natal life of the body proportions, tissues, and anatomical units, the relative changes with age in these characters have been studied in a series of male pigs killed at monthly intervals from birth to 7 months. The study is to be regarded in the light of a preliminary investigation, providing a background to experimental studies on the influence of nutrition on the growth and development of the pig.

2. Growth in body proportions, when measured both photographically and by the weight of the individual anatomical regions, conforms to the law of developmental direction, exhibiting a well-defined anterior-posterior gradient from earlier to later developing regions. The limbs appear as relatively early developing parts with the fore limbs slightly earlier developing than the hind.

3. The major body tissues exhibit marked differential growth behaviour; skeleton, muscle, and fat develop in that order. This situation has its origin in the differential rates of growth of the three tissues, in consequence of which the earlier developing skeleton makes a greater proportion of its growth earlier in life than does muscle, while the latter makes a greater proportion of its growth earlier than does the still later developing fat.

4. Within any one tissue, the individual anatomical units or regions of the body similarly show well-defined differential growth relationships. Thus, the skeletal units of the head and trunk exhibit an anterior-posterior gradient in their order of development, while the bones of each limb show a centripetal gradient, the upper units being later developing than the lower units. To an even more marked degree, both the muscle and the fat surrounding these skeletal units afford evidence of similar gradients in these tissues.
Electrode potentials in laboratory silage
Authors: Common R. H. , Bolton W.
Published: March 2009

1. The average electrode potentials of laboratory silages of various types have been measured.

2. The electrode potentials of ordinary and molassed silages tended to assume values of the order of –0·05 to –0·10 V. from about the third day; thepH of these silages lay in the rangepH 4·0 to 5·5.

3. In a number of instances secondary increases of electrode potential were observed, frequently in association with secondary deterioration.

4. The electrode potential of silage prepared with hydrochloric acid and ofpH 3·4 remained steady around +0·18 V.; the potential of silage prepared with formic acid and ofpH 3·9 was about + 0·35 V. initially but declined towards + 0·23 V. at 35 days.

5. Curves for the ‘pure’ carotene content of laboratory silages displayed minima during the early stages of fermentation except in the case of formic acid silage.
Growth and development in the pig, with special reference to carcass quality characters: Part II. The influence of the plane of nutrition on growth and development
Authors: McMeekan C. P.
Published: March 2009

No attempt will be made to give a detailed summary of all the findings of the present experiment. It is rather our purpose to draw attention to the main principles emerging.

1. The influence of extremes of high and low planes of nutrition during the first 16 weeks of post-natal life upon the growth in body proportions and in anatomical composition has been studied experimentally in six pairs of closely inbred pigs. Quantitative differences in nutrition operative from birth have resulted in an average live weight at 16 weeks of 113 lb. in the High-Plane and 37 lb. in the Low-Plane animals.

2. In body proportions, the head, ears, neck, legs, and body length are penalized relatively less by inadequate nutrition than are body depth, loin, and hindquarters. Conversely, good nutrition favours most the latter characters. These effects upon body form are similarly evident i n the gross weight of the different anatomical regions involved. Low-Plane animals to a large extent retain the proportions of the juvenile and High-Plane approach the conformation of the adult
Fractionation of nitrogen isotopes by animals: a further complication to the use of variations in the natural abundance of 15N for tracer studies
Authors: Steele K. W. , Daniel R. M.
Published: March 2009

A study of the fractionation of nitrogen isotopes in the diet by cattle is described and the results discussed.

Compared with the diet, urine had a lower ratio of 15N to 14N, but faeces, blood and milk all had a higher ratio.

It is argued that the use of natural 15N as a tracer in grazed ecosystems is more complicated than was at first thought.
Efficiency of utilization of food energy by growing pigs
Authors: Burlacu G. , Iliescu Monica , Stavri Josefina
Published: March 2009

The efficiency of utilization of the energy of the food by growing pigs of the Large White breed was measured. Ten diets had a digestible energy varying from 75·3 ± 0·91 to 85·7 + 0·81% and a metabolizable energy from 72·3± ·92 to 83·4±0·64% of the gross energy. Net energy was 85·2±3·20% of the metabolizable energy (ME).

Regression calculations resulted in the following estimates: a maintenance requirement of 151 kcal ME for growing pigs weighing 9–58 kg and efficiencies of 66·7 and 100% for the utilization of ME for protein and fat accretion, respectively.

Feeding regime (ad libitum or restricted at about 80% ad libitum) did not influence food utilization.
Latin rectangle designs for 2n factorial experiments on 32 plots
Authors: Healy M. J. R.
Published: March 2009

Designs are given for factorial experiments with three, four or five factors at two levels each, using thirty-two plots in a 4 × 8 lay-out on the ground. The effects of both rows and columns can be eliminated from the estimate of error. Provided that three-factor interactions can be ignored, information can be retained on all two-factor interactions.