bluuebunny/crossref_metadata_2025 huggingface dataset:
The value of ammoniated sugar beet pulp for dairy cows
Authors: Broster W. H. , Balch C. C. , Bartlett S. , Campling R. C.
Published: March 2009

1. Ammoniated sugar-beet pulp has been compared with decorticated ground-nut meal, when added to a control diet low in protein, in feeding trials with seventy-five cows on three farms and in a balance experiment with four cows.

2. In the feeding trial the cows receiving decorticated ground-nut meal gave 8·4 lb. more milk weekly than cows receiving the control diet. Cows given the diet in which the molassed sugar beet pulp in the control diet was replaced by ammoniated sugar beet pulp gave 7·9 lb. more milk weekly than the control group. The milk-fat percentage was not affected by the treatments. Slight increases in solids-not-fat percentage resulted in an increased yield of solids-not-fat with both high-nitrogen treatments. The increases in milk yield approached statistical significance and the increases in solidsnot-fat were significant.

3. It was concluded that the feeding trial showed that the nitrogen added to sugar-beet pulp during ammoniation could be utilized by milking cows, but the experiment did not permit an estimate of the efficiency of utilization.

4. In the nitrogen balance experiment the utilization of nitrogen was measured as the sum of milk nitrogen and the nitrogen balance. It was concluded that 29·5 g. of nitrogen from 0·8 lb. decorticated ground-nut cake increased the daily utilization of nitrogen by 12·9 g., whereas 55·7 g. nitrogen from 8 lb. ammoniated sugar-beet pulp increased the utilization by only 6·0 g. In this experiment the efficiency of utilization of the nitrogen from groundnut meal was 44% and of the ammonia nitrogen from ammoniated sugar-beet pulp only 11%.

5. Ammoniation raised the crude protein content of molassed beet pulp from 10 to 20%. If for the computation of rations the content of digestible crude protein in sugar-beet pulp is taken as 5·0%, that in the ammoniated pulp should be approximately 7·5%.

6. If given in sufficient amounts the ammonia nitrogen had as great an effect as the nitrogen of ground-nut meal in correcting the effects of a diet low in protein.
Puberal development of Clun Forest ram lambs in relation to time of birth
Authors: Dýrmundsson Ó. R. , Lees J. L.
Published: March 2009

Some aspects of sexual development and the attainment of puberty in Clun Forest ram lambs were studied during the two seasons 1970–1. Strong correlations existed between parameters of penial, scrotal and testicular development. Sexual development in general appeared to be more closely associated with the body growth than the chronological age of the ram lamb.

Nevertheless, marked variation existed in both age and body weight at puberty. Although the majority of the lambs attained this stage of development at 4·5–5 months the age-range extended from 99 to 176 days. The mean body weight at puberty was 32·5 kg, ranging from 24·5 to 38·0 kg. There appeared to be an interaction between chronological age and general body development in relation to the appearance of sperm in the epididymides. Not only did it seem that a certain degree of body growth and testicular size was required before spermatozoa could be released, but also a limit of chronological age below which puberty was not attained. Large differences existed between individual lambs in both testicular and epididymal weights at puberty. There was a high degree of symmetry in growth between the left and the right testes and epididymides.

Time of birth influenced the pattern and rate of body growth and sexual development. This seemed to be largely due to seasonal fluctuations in nutritional conditions during rearing but the results obtained do not preclude the possibility that other seasonal factors, such as the daylight environment experienced by the ram lamb, might have a certain limited influence on sexual development.
The transpiration of corn
Authors: Al-Nakshabandi G. A. , Ismail H. N.
Published: March 2009

The actual transpiration of corn (Zea mays L.) was determined by hydraulic lysimeters, by the inflow-outflow method and by use of a neutrone probe. Two irrigation treatments were used; wet and dry. Under the wet treatment, 740, 858, and 743 mm of irrigation water was used during the seasons 1968, 1969, and 1970 respectively. Under the dry treatment, amount of irrigation water used was 560, 627, and 565 mm during the seasons 1968, 1969 and 1970, respectively. Ratios of actual transpiration (Et) to Penman's estimate of potential evaporation (Eo), evaporation from a Class-B pan (EpB), global radiation (Rg) and net radiation (Rn) were calculated. Values of Et measured by the different methods are in good agreement. Seasonal averages of Et, were 6·2 and 4·9 mm/day under wet and dry treatments, respectively. The Et/Eo, Et/EpB, Et/Rg and Et/Rn ratios increased with leaf area index (L.A.I.) and reached their maximum values when L.A.I, reached its maximum value of 1·03 under wet and 0·92 under dry treatment. The empirical coefficient (f = Et/Eo) under wet treatments was found to be higher than that given by Penman for short grasses and about the same as that obtained by Boumans et al. (1963) for golden-gram (Phaseolus aureus) in Iraq for the months August and September. The empirical coefficient Kb in the Blaney–Criddle formula was greater than the value given by Blaney and Criddle for an arid climate, and less than the value obtained by Boumans et al. for golden-gram in Iraq. It was further found that water use efficiency for grain production was greater under dry than under wet treatments.
Growth and N-uptake by wheat as affected by sowing date and nitrogen in irrigated semi-arid conditions
Authors: Khalifa M. A. , Akasha M. H. , Said M. B.
Published: March 2009

Field experiments were made under irrigated semi-arid conditions to determine the effects of sowing date and nitrogen application on the growth and yield of wheat and nitrogen-uptake by wheat plants. Early sowing was found to be favourable to high grain production because the post-anthesis period coincided with relatively lower temperatures. Late sowing was unfavourable to grain yields since the period between anthesis and leaf senescence was curtailed by the onset of relatively higher temperature. The benefits from nitrogen were greater with early sowing because of higher nitrogen-uptake during early vegetative growth as a consequence of which, nitrogen was readily available to the plants. This resulted in better leaf expansion, and higher leaf-area indices and leaf-area duration. With late sowing nitrogen-uptake was much lower during early vegetative growth and this resulted in decreased leaf expansion, reduced leaf-area indices and leaf-area duration and therefore diminished response in grain yield to nitrogen application.
A factor in the break-down of resistance of ‘Basmati-370’ rice to stem-rot disease
Authors: Mayee C. D. , Rattan B. K.
Published: March 2009

Stem-rot, caused by Magnaporthe salvinii (Catt.) Krause & Webster, is a major rice disease in the Punjab. Varieties of the ‘Basmati’ group, especially Basmati-370, widely grown for its quality, have long been reported resistant to stem-rot (Paracer & Luthra, 1944; Srivastava, Maheshwari & Saini, 1971). Its cultivation in stem-rot-prone areas have been recommended (Grewal, 1975). Recently, however, the authors observed severe stem-rot on Basmati-370 and recorded the variety susceptible (Rattan & Mayee, 1975). Investigation into the causes of breakdown revealed that, wherever the variety had node infection by Pyricularia oryzae Cav., to which it is known to be susceptible, stemrot damage was exaggerated. In the present note, the analysis of breakdown is described.
The estimation of moisture content in the top 10 cm of soil using a neutron probe
Authors: Hanna L. W. , Siam N.
Published: March 2009

The neutron method of estimating soil moisture content in the field has the advantage that once access tubes are installed no further disturbance to the site is necessary and readings can be taken repeatedly throughout the soil profile at a fraction of the time necessary for the gravitational method. However, measurement of moisture content in the surface layer of soil, the top 10 cm, has proved difficult since the source and detector must be at a depth less than the sphere of influence allowing some neutrons to escape to the atmosphere. This air-soil interface effect can lead to an underestimation of moisture content which is greatest in wet soil (Van Bavel, Hood & Underwood, 1954).
An analysis of growth of the potato crop
Authors: Allen E. J. , Scott R. K.
Published: March 2009

Linear relationships between both total and tuber dry-matter yields and the amount of radiation intercepted by potato crops are demonstrated. Their existence suggests that, in the absenceof disease and drought, the essential objective in the production of this crop is to maximize radiation interception. This paper critically assesses the influence of factors which the grower can control on light interception and estimates potential yields for specific environments. The implications of this analysis for growers, breeders, research and the whole industry are discussed.
The validity of the critical size theory for particles leaving the rumen
Authors: Poppi D. P. , Norton B. W. , Minson D. J. , Hendricksen R. E.
Published: March 2009

Three grasses and two legumes, each at two stages of maturity, were fed to three fistulated sheep and samples of the feed, and faeces and contents of the reticulo-rumen, abomasum and ileum were collected for the determination of particle size by wet sieving. Modulus of fineness (MF) was calculated for all particulate matter that failed to pass a 0·15 mm screen. Resistance to flow from the rumen of feed particles of different sizes was also calculated.

The mean MF of the reticulo-rumen contents was 2·56 compared with 5·72 for the feed. Material leaving the rumen and found in the abomasum had a MF of 1·67 and subsequent changes were small and not significant; ileum 1·63, faeces 1·80. Particles greater than 1·18 mm passed out of the reticulo-rumen although the quantity was small (1–3%). The resistance to flow of particles of different sizes from the reticulo-rumen was closely related to particle size with no difference between grasses and legumes or between young and mature forages.

It was concluded that in modelling the flow of particles from the reticulo-rumen a non-compartmentalized approach should be adopted, but if a simple two-compartment model is required then a critical sieve size of about 1·18 mm may be useful, since less than 5% of the particulate material is retained on this sieve size.
Effect of cycocel on the growth, abscission and yield of cotton (Gossypium hirsutum L.)
Authors: Dhillon G. S. , Kler D. S. , Raj Des
Published: March 2009

A large number of flower buds, flowers and premature bolls of cotton are shed without contributing to seed-cotton yield. Abscission may be affected by environmental factors. It may, therefore, be possible to reduce it by modifying the micro-environment within the crop canopy.
Disease development and senescence of the flag leaf of winter wheat in response to propiconazole
Authors: Kettlewell P. S. , Davies W. P. , Hocking T. J.
Published: March 2009

Fungicide applications to wheat have been reported to maintain the green area of the leaves (Dickinson & Walpole, 1975; Stevens & Palmer, 1980). It is not known, however, whether the photosynthetic rate of the leaves is also maintained. It was therefore decided to investigate disease development, green leaf area and photosynthesis of the flag leaf of winter wheat in response to the fungicide propiconazole, which has not previously been reported to influence senescence in the field.
Winter wheat in six-course rotations on light land
Authors: Ridgman W. J. , Wedgwood R. B.
Published: March 2009

Hanley & Ridgman (1979) reported the results from three cycles of six-course rotations on light land. The report was based on a rotation of sugar beet, barley, barley, potatoes, barley, barley, with treatments involving replacement of one, two or three of the first three crops by 1-, 2- or 3-year leys, the last three crops acting as test crops. One of the problems of drawing general conclusions from rotation experiments is that the test crops are really part of the experimental treatments and may not be the most suitable crops for determining either the direct effects of the ‘treatment’ crops or the longer-term effects of the rotations themselves.
Studies on the production of volatile fatty acids from grass by rumen liquor in an artificial rumen: I. The volatile acid production from fresh grass
Authors: John A. , Barnett G. , Reid R. L.
Published: March 2009

1. A study has been made over two growing seasons of the volatile fatty acid production from ley grass obtained from a single area of one field, under the action of rumen liquorin vitro.

2. The acida estimated were acetic, propionic, butyric, valeric and caproic. On only one occasion did the last named appear in measurable amount.

3. The main acid produced in early stages of the year is acetic acid, but as the season advances propionic acid becomes the acid of major production.

4. In parallel cellulose runs it was found that propionic acid was invariably produced in greater amount than any other acid.

5. An attempt has been made to eliminate, by using cellulose as a standard, the effects of using different rumen liquor samples.

6. The dried samples, corresponding to the fresh material, were invariably found to yield acetic acid in greater proportion than propionic acid. The average percentages of acids obtained from the dried grass were similar to those found by other workers. It is suggested that the variations between the fresh and dried grass results are due to changes in carbohydrate content resultant upon storage of the latter.
Results from barley experiments comparing aqueous ammonia and aqueous urea with ammonium nitrate, and also liquid with granular NPK fertilizers
Authors: Widdowson F. V. , Penny A. , Flint R. C.
Published: March 2009

In 14 experiments made from 1968 to 1970 yields of, percentages of N in and amounts of N removed by the grain were compared: (1) when N was injected, either as aqueous ammonia (with or without a combine-drilled ‘starter’ dose of N) or as aqueous urea, or when broadcast as ammonium nitrate (‘Nitro-Chalk 21’) and: (2) when comparable liquid (14–6–8) and granular (20–10–10) NPK compound fertilizers were applied, either over the seed bed (sprayed or broadcast), or combine-drilled. All were applied to give 63 or 126kgN/ha.

Barley yields were increased significantly more by combine-drilled than by broadcast PK (0–20–20) fertilizer, especially when only 32 kg P2O5 and K2O/ha was given. N was better combine-drilled than broadcast when 63 kg/ha was given, but not with 126 kg/ha. Soil analyses suggested a limiting value for P.

Yields and N recoveries were largest when one-fifth of the N was combine-drilled (as 6–15–15) and the remainder injected as aqueous ammonia in bands 30 cm apart and 12 cm deep. Injecting all the N, either as aqueous ammonia or as urea, gave yields a little smaller than this, but still larger than from broadcasting ammonium nitrate.

The liquid NPK fertilizer gave smaller yields than the granular one in the two dry springs (1968 and 1969), but similar yields in the cool wet one (1970), both when applied over the seed bed and when combine-drilled. The smaller yields with the liquid fertilizer were associated with a severe check and loss of plant when it was combinedrilled (presumably caused by urea) and poorer growth after it was sprayed (presumably through loss of N to the air and greater dispersal of P in the soil). The single amount of each fertilizer increased yields more when combine-drilled than when broadcast, but not the double amount, which, especially as liquid, was safer when surface-applied. Effects of site and season upon mean yields were large.
Response to family selection based on replicated trials
Authors: England F.
Published: March 2009

The theory of expected response to selection between families is extended to allow for the effects of field replication and its interactions with number of plants per plot.
Response of Yankasa sheep to various lengths of water deprivation
Authors: Umunna N. N. , Chineme C. N. , Saror D. I. , Ahmed A. , Abed S.
Published: March 2009

The effects of various lengths of water deprivation were studied with Yankasa sheep fed either a high roughage or a high concentrate diet in two experiments. Water was given once in 24, 48, 72 and 96 h. Free water intake decreased linearly (P < 0·01) as the period of water deprivation increased but feed intake was not similarly affected. There was a marked decrease in live-weight gain and consequently a decline in feed efficiency (kg gain/kg feed). In the metabolism study, there was a tendency towards reduced mean faecal and urinary nitrogen excretion, faecal moisture content and increased mean nitrogen retention and nitrogen and dry-matter digestibilities as the period of deprivation increased. Rams given water once in 72 and 96 h were very inactive and dull and one and three rams respectively, died of severe dehydration from those treatments in Expt 2.
The effects of breed, breeding system and other factors on lamb mortality: 1. Causes of death and effects on the incidence of losses
Authors: Wiener G. , Woolliams Carol , Macleod N. S. M.
Published: March 2009

The incidence of lamb mortality from birth to 8 months of age has been studied over a 6-year period in an upland, grassland flock of sheep comprising the Scottish Blackface, Cheviot and Welsh Mountain breeds and the crosses among these breeds. Each breed and cross-bred type was maintained at varying levels of inbreeding. Approximately half the lambs which died were stillborn or dead on the day of birth, nearly 40% died thereafter but before weaning and about 10% after weaning.

Post-mortem examinations on 586 of the 632 lambs which died from among the 2453 born attributed death on average to two causes per lamb. Approximately 11% of the causes were stillbirths or delayed births; 11% were cases of dystokia; congenital defects of various types accounted for about 10% of the causes; 25% made reference to weakly lamb, exposure or starvation; 14% to infectious diseases and 16% to noninfectious diseases. The extent to which causes of death occur together is examined.

Breeds differed in mortality rate with the Welsh the lowest and Cheviot the highest. Cross-breds were better than the average of the pure breeds but this advantage emerged only in the period between 3 days and. 6 weeks of age. Inbreeding, both of dam and of lamb, increased mortality. Lambs from dams which were crosses of inbred lines had the best survival. Litter size, type of rearing, parity of dam, sex of lamb and birth weight also had significant effects on mortality rate.
Evaluation of the effects of environmental temperature and nutrition on body composition
Authors: Dauncey M. J. , Ingram D. L.
Published: March 2009

The body composition of young mammals has been investigated in relation to environmental temperature and energy intake. Piglets were weaned at 14 days and then kept separately at 35 or 10 °C and fed either a high or a low energy intake. The animals were killed at 38, 48, 56 or 64 days of age and the carcass divided into four compartments: superficial tissue (skin and subcutaneous adipose tissue), muscle, contents of abdomen (gastro-intestinal tract, liver and kidneys), contents of thorax (heart and lungs). Each compartment was analysed for fat, nitrogen and energy content.

The results were analysed using a non-orthogonal analysis of variance in oider to investigate the separate effects of environmental temperature and energy intake, to test for possible interactions between these two factors, and to assess the time it takes for any effects to develop.

The total amount of fat stored in the body was greater in the pigs kept at the high temperature than in those kept at the low temperature and increased with an increase in food intake; there was no evidence of an interaction of temperature and diet, suggesting that their effects were exerted independently. The extra fat was stored mainly in the superficial tissue and muscle, but partly also in the deep body compartments. However, when expressed as a percentage of the total fat store a greater proportion was found in the deep body compartments of those kept at the low temperature and on the low intake, although the absolute quantities of fat involved were small.

The nitrogen content was also greater at 35 than at 10 °C, and on the high than low intake. Most of the nitrogen was present in the muscle and the proportion of the total body nitrogen stored here was greater in the warm than in the cold, whereas it was unaffected by energy intake. The energy contents of the tissues measured by bomb calorimetry and estimated from the chemical composition were similar. For animals kept at 35 °C most of the energy was stored in the superficial tissue, with the muscle as the second highest store. By contrast, those in the cold stored most of their energy in the muscle.

The present investigation has thus highlighted the large and partly independent effects that environmental temperature and food intake can have on the distribution of energy within the body and the chemical form in which it is stored.
Water relations of winter wheat
Authors: Gregory P. J. , McGowan M. , Biscoe P. V. , Hunter B.
Published: March 2009

The authors regret the following errors: Page 102, Appendix Table 1, lines 13, 15, 17, 20 and 22 of the Table should be amended as follows:
Trace metal contamination of soils and vegetables in Shipham, Somerset
Authors: Davies B. E. , Ginnever Rhoda C.
Published: March 2009

Copper, lead and zinc ores have been mined in past years in many western counties of Great Britain leaving a legacy of extensive soil contamination. A survey of north-east Clwyd (Davies & Roberts, 1978) revealed that in the Halkyn Mountain area some 171 km2of land are contaminated by lead and 69 km2by cadmium (including 13 km2containing from 10 to 540 mg Cd/kg soil). The Mendip Hills of Somerset are an ancient leadzinc mining area similar in many ways to Halkyn Mountain and, after some reconnaissance sampling in 1972 and 1974, a trace element survey was initiated in 1977. Topsoil samples (174) were collected on an approximately regular 2×2km grid from a 600 km8 area of north Somerset including the Mendips (B. E. Davies and R. C. Ginnever, unpublished results). This survey revealed that the Mendips were generally contaminated by cadmium, lead and zinc. Highest soil lead values were found near Wells (11 g/kg) and Charterhouse (73 and 80 g/kg) but in the case of cadmium the survey revealed that some 2 km2of land around the village of Shipham contained values exceeding 10 mg Cd/kg. Preparatory to detailed investigations planned for 1979 a reconnaissance survey of soils and vegetables from the village was made. Meanwhile, the Department of the Environment announced the results of another (independent) survey which also demonstrated that Shipham possessed a considerable cadmium problem (e.g. McGinty, 1979). A full account of our survey of north Somerset will be published and this paper presents the results from the reconnaissance of Shipham.
Effect of sexual preparation procedures on semen characteristics in the ram
Authors: McGrath P. E. , Boland M. P. , Gordon I.
Published: March 2009

Quantitative information concerning preejaculation sexual preparation of bulls was published some years ago by Collins, Bratton & Henderson (1951), who concluded that about 40% more motile sperm could be obtained by imposing one false mount before ejaculation. It had been suggested that one false mount in bulls is essentially as efficient as two such attempts in terms of sperm output (Branton, D'Arensbourg & Johnston, 1952). More recently Hafs, Knisely & Desjardins (1962) have shown that bulls given a planned 5 min sexual preparation yielded 30% more sperm than those given no preparation. Similarly 10 min preparation resulted in a 12% increase in sperm output when compared with a 5 min preparation. These authors also showed that zero, one, two or three false mounts significantly affected motile sperm output.
Effects of induced, subclinical phosphorus deficiency on feed intake and growth of beef heifers
Authors: Gartner B. J. W. , Murphy G. M. , Hoey W. A.
Published: March 2009

Hereford heifers were fed a diet (7·0 MJ ME/kg D.M.) containing 0·09 % phosphorus but complete with regard to other nutrient constituents. Only after 19 weeks wore the effects of subclinical aphosphorosis evident in the form of reduction in feed intake, cessation of weight gain, increased feed conversion and decreases in tho concentration of inorganic phosphorus in blood and saliva. Heifers supplemented daily with 12 g phosphorus sustained a weight gain of about 0–2 kg/day over 62 weeks as did other supplemented heifers whose feed intake was restricted to that of tho low phosphorus treatment. The effects of phosphorus supplementation were thus demonstrated without being confounded by concomitant increases in feed intake.

Phosphorus supplementation resulted in significantly lowered apparent crude protein digestibility and a slight increaso in cell wall digestibility.
Utility of Rhizobium in the phyllosphere of crop plants under field conditions
Authors: Nandi A. S. , Sengupta B. , Sen S. P.
Published: March 2009

Soya bean, Bengal gram and lentil plants were grown under field conditions and sprayed with suspensions of different strains ofRhizobium. Irrespective of crossinoculation groups beneficial effects were similar to those observed in nitrogen-free sand culture with respect to dry weight, chlorophyll and N contents. The beneficial effects of sprayingRhizobiumstrains compared favourably with seed treatment by appropriateRhizobiumstrains and application of urea. Both an ineffective strain and a mutant strain ofR. japonicumshowed similar beneficial effects. Acetylene reduction by theRhizobium-leafassociation ranged from 497 to 890 nmol/g leaf/h. The ectosymbiotic association ofRhizobiumwith foliage of legumes, thus, may meet to a large extent the nitrogen requirement of such plants.
Water diffusivity of germinating soya-bean, cow-pea and blackgram seeds at both large and small times
Authors: Sen H. S. , Rao A. V. Suriya , Mahata K. R. , Das P. C.
Published: March 2009

Theory for the non-steady-state diffusion flow of a spheroidal body is discussed and solutions are presented for estimating the time-dependent diffusivities at small and largo times following sowing in soil of germinating soya-bean, cow-pea and blackgram seeds. The validity and also the limitations of the equation for large times to estimate time-dependent diffusivities are discussed. Assuming that the time of germination was at infinity it was possible to reduce the equation for small times to a simple form. Thus, with the help of these two equations it was possible to study changes in the diffusivity of seeds at different soil matric potentials throughout the period, immediately after sowing until germination. The diffusivities showed gradual decrease at 0 bar potential for soya-bean and cow-pea, and increase at – 2 and – 10 bar potentials for soya-bean, cow-pea and blackgram seeds with time. The decrease in diffusivity with time under non-stress soil water condition is explained as predominantly a physiological phenomenon of the seed due to the increase in seed water content with time, while its increase with time under water stress conditions is probably because of the decrease with time of the initially large seed-coat resistance and tortuosity showing small values of diffusivity. The discussion suggests that the role of area of contact on the water uptake of the buried seeds as reported so far is contradictory and, therefore, not convincing.
Yield variability of crop varieties in the U.K.
Authors: Talbot M.
Published: March 2009

This paper provides estimates of varieties × environments and plot error variances based on more than 1000 trials of varieties of oats, barley, wheat, perennial and Italian ryegrass, timothy, cocksfoot, potato, sugar beet, swedes, autumn kale, forage maize and field beans. Tables of critical differences and acceptance probabilities are presented to guide in planning future series of trials.
Response of sunflower cultivars to plant density and nitrogen
Authors: Narwal S. S. , Malik D. S.
Published: March 2009

In a 2-year study, sunflower oultivar EC 69874 produced greater leaf area than EC 68415, but gave similar grain yields. The former was superior in leaf area, head size and yield per plant but was inferior in 100-seed weight. The leaf area was greater at lower plant density (5·5 plants/m2), which resulted in higher 100-seed weight, number of seeds per plant and yield per plant than higher plant density (11·1 plants/m2). Plant density had no influence on the percentage of filled seeds or oil content. Application of nitrogen improved the leaf area, flowerhead size, percentage of filled seeds, 100-seed weight, yield per plant and grain yield up to 60 kg/ha but decreased the oil content.
Effects of applied nitrogen on grass yield, nitrogen content, tillers and leaves in field swards
Authors: Wilman D. , Pearse P. Joy
Published: March 2009

Effects of three levels of N application and four intervals between harvests on field swards of perennial ryegrass (Lolium perenne L.) were studied during 6-week periods in summer and spring. Ryegrass was compared with tall fescue (Festuca arundinacea Schreb.) in spring and autumn.

An increase in the interval between harvests from 1 to 6 weeks allowed a larger, positive response to applied N to develop in respect of dry-matter yield, weight per tiller, and leaf blade and sheath length. Response to N was expressed more in terms of larger leaf blades than in a larger number of tillers. Tall fescue leaf blade size was increased more than that of ryegrass by a period of uninterrupted growth in May.

Within 1 week of its application, N had increased the N content of both emerging and dying leaf blades and had increased the width and reduced the weight per unit area of the emerging blades. The positive effect of N on blade width (and on blade length where uninterrupted growth was allowed) and its negative effect on weight per unit area were ‘carried through’ the sward, to be recorded a second time when that generation of blades had become the dying blades.

Applied N increased the number of tillers, the rate of emergence of new tillers, the proportion of tiller buds which developed into tillers, and the proportion of relatively young tiller buds which developed.
Breed structure in the pedigree Ayrshire cattle population in Great Britain
Authors: Wiener G.
Published: March 2009

Ayrshire Cattle Herd Booksfor the years 1927, 1946 and 1947 were examined to study the breed structure. Extended pedigrees of a sample of registered females showed that more than half their genes had come from eight herds. Most of the genetic contribution of these herds comes through the bulls they breed.

Herds were divided into: breeders' herds (a), breeders' herds (b), multipliers' herds (i), multipliers' herds (ii), and herds registering males only. The function and numerical importance of each group is shown. The position of any one herd in the breed hierarchy is unstable. Changes in the extent of specialization of herd function between 1927 and 1946 are described.

The Ayrshire breed structure is discussed in the light of its implications on the effective size (N) of the population and on the selection of bulls for breeding.
Breed differences in copper metabolism in sheep
Authors: Wiener G. , Suttle N. F. , Field A. C. , Herbert J. G. , Woolliams J. A.
Published: March 2009

Evidence was sought for genetic differences in the absorption or systemic use of copper by comparing responses in plasma Cu concentration to oral and intravenous Cu repletion. Lambs of the North Ronaldsay (Orkney), Scottish Blackface and Welsh Mountain breeds and crosses of these with the North Ronaldsay were used.

In two oral repletion phases average Cu intakes/kg live weight were 0·87 and 0·63 mg/week and similar for all breed groups. Plasma Cu concentrations of Scottish Blackface lambs showed little or no increase while those of North Ronaldsay lambs increased rapidly, and those of Welsh Mountain lambs increased moderately. The plasma Cu concentrations of the cross-breds increased more rapidly in the first than in the second phase; their rate of change lay between the pure breeds but was closer to that of the North Ronaldsay in the first phase.

The rates of increase in plasma Cu concentration during intravenous repletion were relatively uniform for the different breeds and crosses except the Blackface which showed a lower rate. It was concluded that the large differences between groups in response to oral Cu repletion were largely attributable to differences in the efficiency of Cu absorption.
Inter-plot competition in variety trials of field beans (Vicia fabaL.)
Authors: Kempton R. A. , Lockwood G.
Published: March 2009

Four trials were carried out to investigate the effect of inter-plot competition on seed yield and plant height of field beans using experimental designs balanced for neighbours. One trial tested four varieties ranging in final height from 25 to 100 cm and sown in four-row plots with 30 cm spacing between rows and one blank row between plots. When grown between plots of a dwarf variety, the plot yield of the tallest variety was increased by 20% compared with its pure stand yield: a complementary reduction in yield was shown by the dwarf variety when grown between plots of the tall. The effect on the yield of the inner rows of the plot was somewhat smaller than that of the outer rows but still significant. Another trial with six commercial varieties differing in final height by less than 15 cm showed no differential effects of inter-varietal competition on yield. In two trials with six varieties of widely differing heights planted with 50 cm spacing between rows, but no gap between plots, plot yield was strongly affected by the neighbouring variety in the trial with single-row plots, while yields from the four-row trial showed a large interaction between variety and inner and outer row position, again indicative of inter-variety competition. The yield response to competition could be described by a common linear regression on the excess height of plot neighbours: there was little evidence of varietal differences in sensitivity or aggressiveness.

Plant height showed a positive response to height of plot neighbours in all four trials, whilst in the single-row trial, the ratio of grain yield to total dry-matter production (harvest index) was negatively related to excess height of neighbours.

The results suggest that, when testing varieties differing in height by more than 20 cm, at least two buffer rows, e.g. six-row plots with the centre two rows harvested, are required to obtain a true comparison of pure-stand yield. Alternatively, when this procedure would result in an unacceptable use of resources, one of the statistical models adapted in this paper may be used to adjust variety yields for pure stands.
Evaluation of the performance of cassava (Manihot esculenta Crantz) when grown from inverted stem cuttings
Authors: Onwueme I. C.
Published: March 2009

In order to investigate the characteristics of inverted cassava plantings, seven-node cuttings were planted upright or inverted, and such that four nodes of each cutting were within the soil in a glasshouse. They were observed for 7 weeks. The inverted cuttings sprouted less rapidly, but the percentage of the cuttings which eventually sprouted was not decreased. The inverted cuttings produced more sprouts than the upright ones, and a greater percentage of their sprouts were produced below ground than for the upright cuttings. At 5 and 7 weeks, the total leaf area per cutting was less for the inverted cuttings. The number of leaves per cutting did not differ between the treatments.

In a field experiment comparing upright and inverted stem pieces, field emergence and tubering were slower in the inverted cuttings. Yield per plant and per unit area was significantly lower for the inverted cuttings. In the upright planting, most of the tubers originated at the lowest extremity of the cutting and formed a compact bunch there. For the inverted planting, most of the tubers arose from the shallower-lying submerged nodes, but the tubers did not form a compact bunch. The inverted planting had a lower percentage of its tubers lying along the ridge. In a few of the inverted plantings, but not in the upright, the bases of some stems became tuberous. The treatments did not differ with respect to mean tuber length, radius of spread of the tuber tip, and the number of major stems per plant.
Some preliminary observations on the histological development of the fore-stomachs of the lamb I. Histological changes due to age in the period from 46 days of foetal life to 77 days of post-natal life
Authors: Wardrop I. D.
Published: March 2009

1. A general survey of the histological changes of the fore-stomachs of the lambs from 46 days of foetal life to 77 days of post-natal life is presented.

2. In all the rumen foetal specimens the mucosal surface was smooth. At birth small, conical papillae were visible and from this age onwards these papillae increased rapidly in size and tended to be long and tongue-shaped in appearance. Little change occurred in the appearance of the rumen papillae after 56 days of age.

3. The outlines of the reticulum reticular ribs were visible in the 100-day-old foetal specimen. At birth the normal honeycomb-like structure of the reticulum was well developed, but the papillae on and between the reticular ribs were small and had rounded tips. From 20 days of age onwards the reticulum features increased in size and the papillae became pointed in shape.

4. At 46 days of foetal life the omasum wall was folded to form developing laminae and by 70 days of foetal life laminae of four orders were present. The main age changes in the appearance of the mucosal surface from this age onward was an increase in the length of the laminae, the formation of small conical papillae on the laminae, and an increase in the inter-laminae spaces.

5. All three fore-stomachs showed the same general histological changes with age. The epithelium changed from a stratified cuboidal type in the foetal specimens to a keratinized, stratified, squamous epithelium in the post-natal specimens. The basal layer of the epithelium became folded to form papillae, reticular ribs and laminae, and in the rumen and reticulum further folding of this layer took place to form papillary bodies.
Some preliminary observations on the histological development of the fore-stomachs of the lamb II. The effects of diet on the histological development of the fore-stomachs of the lamb during post-natal life
Authors: Wardrop I. D.
Published: March 2009

1. A study on the effects of the type of diet on the histological development of the fore-stomachs of the lamb is presented.

2. The rumen papillae were well developed in a 7-week-old lamb that had been fed solely on milk from birth, but compared to a lamb of the same age that had access to lucerne chaff from birth, they were smaller in size and more conical in shape. There was no difference in the appearance of the rumen mucosal surfaces of two lambs of 13 weeks of age, one of which had access to lucerne chaff from birth and the other access to lucerne chaff for only 4 weeks prior to slaughter.

3. The type of diet appeared to have little effect on the appearance of the reticulum mucosal surface.

4. The appearance of the omasum mucosal surface was only normal when lucerne chaff was fed to lambs.

5. The histology of the rumen wall was normal in the milk-fed lamb. However, compared to the lamb of the same age that had been fed on lucerne chaff, the papillary body formation, stratum granulosum and stratum corneum were less well developed.

6. Apart from a thinner stratum granulosum and stratum corneum, the histology of the reticulum wall of the milk-fed lamb was little different from that of the lamb of the same age that had been fed on lucerne chaff.

7. The histology of the omasum wall of the 7-week-old milk-fed lamb was very similar to that found in the lamb at birth.
Laboratory and field evaluation of certain pesticides against the adults and eggs ofTetranychus cinnabarinusBoisduval on cotton
Authors: Marei A. S. M. , Saad A. S. A. , Tantawy G.
Published: March 2009

The effectiveness of certain pesticides a ainst adults and eggs ofTetranychus cinnabarinusBoisduval infesting cotton was sti died. Kelthane S and Rogor gave the best performance in the field evaluation, whilu Kelthane, Dursban and Cyolane were best in the laboratory evaluation. Specific acaricides were generally more toxic than the other insecticides on both adults and eggs of the mite. The slide-dip method was more sensitive for testing Kelthane, Dursban and Cyolane.
Irrigating seedling tea in Southern Tanzania: effects on total yields, distribution of yield and water use
Authors: Carr M. K. V.
Published: March 2009

In a dry area of Southern Tanzania with a single rainy season irrigation during the six-month-long dry season (May-November) doubled the total annual yield of tea and at the same time evened its distribution over the year to some extent. Other factors including low temperatures limited growth rates during the period June-September despite irrigation, whilst a lull in production in November appeared to be unrelated to external factors. Roots were traced to depths of about 4·3 m and by the end of the dry season unirrigated bushes were drying the soil below 3m. In general total yields decreased with decreasing frequency of irrigation and quantity of water applied but because these plants were deep rooting they could withstand deficits up to 100 mm without a reduction in yield, equivalent to a loss of about 25% of the total available water in the profile. There was some evidence that the most economical use of water occurred when the soil was not rewetted to field capacity at each irrigation, although yields were then less. Irrigation also reduced the incidence of a stem canker,Phomopsis theae. The implications of these results to the tea industry of East Africa are discussed.
Changes in the availability of dietary copper to young lambs associated with age and weaning
Authors: Suttle N. F.
Published: March 2009

64Cu and an indigestible 103Ru-labelled marker were administered into the alimentary tract of six artificially reared lambs on four occasions, 28 and 14 days before weaning and 15 and 42 days after weaning. The ratio of 64Cu: 103Ru excreted in the faeces was used to measure the apparent availability of Cu.

Mean Cu availability decreased from 71·0 ± 3·7 to 47·2 ± 7·8% immediately before weaning and to 10·8 ± 1·4% 15 days after weaning.

The relationship between availability (y, %) and age (x, days) prior to weaning was described by the equation

When half of the lambs were given abomasal doses of 64Cu + 103Ru 42 days after weaning, the mean Cu availability was 21·4±4·0% compared with 3·7±2·1% for those dosed via the rumen.

64Cu present in the whole plasma volume 20 h after dosing (y, % dose) was highly correlated with availability (x, %), the equation being

Four out of a group of eight milk-fed lambs were given access to a proprietary concentrate from birth and milk intake was progressively restricted so that by 15–21 days they were wholly dependent on the concentrate. Mean Cu availability at 23 days was 8·3±3·4% compared with 75·0±5·4% for lambs continuing to receive milk substitute alone. The corresponding values for 64Cu in plasma were 0·34±0·03 and 1·41±0·14% dose.

Less than 1·1% of the 103Ru and 64Cu doses were excreted in the urine after 48 h and no 103Ru was detected in the plasma.

The nutritional significance of and mechanisms for the reductions in Cu availability with age and weaning are discussed and methods for measuring Cu availability compared.
The ‘teat order’ of suckling pigs: I. Relation to birth weight and subsequent growth
Authors: Fraser D. , Jones R. Morley
Published: March 2009

Teat orders were determined for 76 litters of Large White and Large White × Landrace pigs. Regression analysis within litters revealed a relationship between suckling position and weight both at birth (P<0·01) and at 3 weeks of age (P<0·001), with the heavier piglets tending to occupy the more anterior teats. The correlation coefficients, however, were very small (r = –0·16 and –0·22 respectively). The correlation between birth weight and 3-week weight was much larger (r = +0·47); and a comparison of pairs of litter-mates showed that a difference in birth weight of 0·25 kg or more persisted at 3 weeks in the majority of cases, regardless of which piglet suckled the more anterior teat. Birth weight accounted for much more of the variation in 3-week weight than did teat number, and, when the effect of birth weight had been taken into account, teat number accounted for only an additional 2·3% of the variation. Even so, the anterior teats did appear to confer some advantage which was independent of that of the birth weight of the piglets suckling these teats. From the results of this and other studies it is concluded that there is only a weak relationship between suckling position and weight at birth and 3 weeks. Other unidentified factors are probably of more importance for the within-litter variation in weight gain of suckling pigs.
A study of feeding types and certain rumen functions in six species of South African wild ruminants
Authors: Giesecke D. , Gylswyk N. O. Van
Published: March 2009

In order to characterize the rumen digestive physiology of South African wild ruminants investigations were made on a total of 35 individuals of six species killed in various regions during the dry season.

In buffalo, blue wildebeest and gemsbok grasses constituted 85–100% and in impala, springbok and kuduless than 10% of the diet. In the case of the latter three species effects of the habitat and of predilection for certain plant materials were apparent.

Compared with the grazers, the species feeding mainly on plant material other than grass were characterized by a smaller physiological capacity of the rumen reticulum, higher counts of ciliate protozoa and ‘large bacteria’, higher levels of rumen ammonia and higher molar proportions of rumen propionate and valerate. Within these feeding types differences between species were indicated.
Variation in plasticity within the S. 23 cultivar of Lolium perenne L.
Authors: Valentine J. , Charles A. H.
Published: March 2009

The S. 23 cultivar of Lolium perenne L. has the ability to perform well in a wide range of environments and an experiment was designed to examine the phenotypic plasticity of S. 23 genotypes with particular reference to the level of nitrogen application.

Genotypes of S. 23 grown in a controlled growth room at close spacing (5 cm) showed a wide range of dry-matter yields with the highest yielding 144 times that of the lowest at the last of six cuts taken at 4-week intervals. Genotypes maintained much the same order of yield from one nitrogen level to another, but there were exceptions. Regression techniques were used to further quantify genotype-environment behaviour and to measure response to the environment in which the plants were grown. Considerable variation in this character occurred and the correlation of mean yield and response was incomplete. Some of the genotypes combined the desirable characters of high mean yield and good response to improved environments, while others had high mean yields, but were not as well adapted to the highest N level.

In the experiment no significant effects could be traced to differences in age of seed, but plants which had been maintained vegetatively for 7 years showed reduced vigour.