bluuebunny/crossref_metadata_2025 huggingface dataset:
The use of vaginal sponges in spring breeding of Mutton Merino and cross-bred ewes
Authors: Goot H. , Schindler H.
Published: March 2009

Fifty-nine Mutton Merino and cross-bred 2-year-old and older ewes were allotted to two groups according to age, weight and breeding performance in the preceding 1966/67 in-season. In the experimental ewes the treatment started on 22 March 1967 and consisted of vaginal sponges (Syncro-Mate) inserted for 17 days and 750 i.u./ewe of P.M.S. injected on the day of the removal of the sponges.

As from 1 March, all the ewes were ‘teased’ daily but hand service commenced on 20 April, to coincide with the 13th day after the removal of the sponges.

At the time of sponge insertion, approximately a third of the ewes, in each group, were already cycling. The treatment advanced the average post-treatment oestrus by 8 days, out of a possible 15 days, synchronized it in 70% of ewes and shortened the tupping season in 97% of treated ewes to 9 days (23 days in controls), but otherwise the performance of the treated ewes (and their offspring) did not differ from that of the controls. In both groups forty ewes lambed (68%) and fifty lambs were born (85%). Out of nineteen dry ewes, five were in anoestrus and in at least nine, an early death of the embryo could be suspected. Among the reproductive activities during the preceding in-season, date of weaning, days of suckling and barrenness may be implicated in the failure to breed in the spring.
Residual value of basic slag, Gafsa rock phosphate and superphosphate in a sandy podzol
Authors: Mattingly G. E. G.
Published: March 2009

Surface soils (0–15 cm) from a field experiment on a sandy podzol were used to evaluate the residues from basic slag, Gafsa rock phosphate and superphosphate (using ryegrass in pots), and to measure the solubility and buffer capacity during cropping, and the distribution of the residual phosphate in different particle-size fractions of the soil.

After applying P at about 3·6 g P/m2/year for 6 years, residues of the three P fertilizers were equivalent but after applying more P (9–11 g P/m2/year) for a further 8 years, basic slag and rock phosphate gave larger labile P values, were more effective for ryegrass and buffered soils more than residues of superphosphate. The percentage recoveries of P from the surface soils were approximately 7, 40 and 65 % of the total applied in 8 years as superphosphate, basic slag and rock phosphate respectively.

Residues from basic slag (mainly 75–20 μm particles) accumulated in the < 20 μm fraction of the soil. Rock phosphate (mainly 200–20 μm particles) dissolved more slowly and about one-half of the material > 20 μm remained in the sand fractions of the soil.

Residues from rock phosphate maintained values of ½pCa + pH2PO4 and pH–½pCa consistent with the solubility of fluorapatite, even when P was removed from the soil by exhaustive cropping with ryegrass. Residues from basic slag were more soluble than hydroxyapatite.
The effect of intra-ruminal feeding on the intake of silage
Authors: McLeod D. S. , Wilkins R. J.
Published: March 2009

A ryegrass silage with pH of 3·8 was prepared and part was neutralized to pH of 5·4 with sodium bicarbonate. Sheep were fed ad lib. in four treatments in which the two silage feeds were fed with either all the feed being consumed per os or with the introduction of silage (15 g D.M./kg LW0·75 per day) directly into the rumen through a fistula. Intake per os was significantly higher (P < 0·001) for the modified silage than for the original silage and was significantly lower (P < 0·001) for the treatments which included feeding per rumen rather than all the food being consumed per os. Feeding per rumen resulted in a small but significant (P < 0·05) increase in the total (per os + per rumen) intake of both types of silage. This increase in intake through feed being introduced directly into the rumen suggests that factors sensed in the oro-pharyngeal region which were by-passed with this treatment may have some limiting effect on the intake of both these silages. The effect of the introduction of feed directly into the rumen on intake per os was similar for the two silage feeds, despite much higher levels of consumption of the modified silage for both feeding methods. This suggests that the increase in intake brought about by partial neutralization was not mediated through this treatment affecting any oro-pharyngeal limitation on the intake of silage.

Volatile fatty acid concentrations in the rumen were higher for the modified silage treatments, but differences between silage treatments for molar proportions of volatile fatty acids, rumen pH and rates of cellulose digestion were non-significant. The initial digestion of cellulose was slower, the molar proportions of acetic acid were lower and of propionic acid higher for treatments which involved feeding per rumen rather than all the food being consumed per os. These observations are discussed in relation to the use of the intra-ruminal feeding techniques and to possible factors limiting the intake of highly acid silages.
Effects of nitrogen fertilizer, plant population and irrigation on sugar beet: II. Nutrient concentration and uptake
Authors: Draycott A. P. , Durrant M. J.
Published: March 2009

The concentration of nitrogen, phosphorus, potassium, sodium, calcium and magnesium was measured in the dry matter of sugar beet from four field experiments (1966–9). All combinations of four amounts of nitrogen fertilizer (0–1·8 cwt/acre), four plant populations (8800–54000 plants/acre) and irrigation were tested, which gave a wide range of plant size and yield. Nutrient concentration and uptake by the crop were also greatly affected by the treatments.

Nitrogen fertilizer and irrigation increased uptake of nitrogen by the crop but increasing the plant population had little effect on uptake and decreased the concentration of nitrogen. Sugar yield was related to the total nitrogen concentration in tops and roots and to uptake. There were optimal values of nitrogen concentration for maximal sugar yield, but the optima were greatly affected by plant population. Leaf colour was a good guide to nitrogen concentration.

Phosphorus concentration was affected little by the treatments but cation concentrations were greatly affected. In general, uptake of all the elements was increased by all treatments – the exception was sodium, which decreased as the plant population increased but this was balanced to somo extent by increased potassium uptake.
The interrelationship of some components of forage quality
Authors: Thomson A. J. , Rogers H. H.
Published: March 2009

To produce forage crop varieties of improved quality, the plant breeder must consider both the content of the quality components and their interrelationships. The methods used to examine the interrelationships involve simple correlations and path analyses. In the path analyses a dependent variate is specified which is completely and additively determined by a number of independent variates. The amount of variation present in the dependent variate accounted for by variation in each of the independent variates is calculated. The effects of an increase in the mean content of one of the quality components on the other components in the path system is predicted.

As an example of the method, data for two years is analysed from timothy polycross progenies grown as swards and spaced plants. Primary and subsequent growths are compared.

There are inconsistencies in the interrelationships of the quality components between years and between swards and spaced plants. Although only phenotypic statistics were calculated, the findings have implications in relation to plant breeding.
The effects of nitrogenous fertilizer on the nutritive value of artificially dried grass
Authors: Blaxter K. L. , Wainman F. W. , Dewey P. J. S. , Davidson J. , Denerley H. , Gunn J. B.
Published: March 2009

1. A field trial in which a sward, predominantly of S. 24 ryegrass was fertilized with 248, 301, 532 or 589 kg N/ha showed that a maximal yield of 13·1 tonnes/ha of artificially dried grass could be obtained from four harvests in the year.

2. The materials harvested ranged in crude protein content from 10·1 to 23·6% and in apparent digestibility of dry matter from 72 to 76%. The amounts of the grasses voluntarily consumed by sheep were slightly and significantly lower for those containing the least N × 6·25.

3. In feeding trials with twenty-five steers, a barley diet was compared with a diet entirely of dried grass from the 3rd and 4th harvests from an area in the same field which had received 487 kg N/ha. The cattle given the barley diet consumed 8·7 kg/day and gained 1·22 kg/day. Those given dried grass consumed 8·9 kg and gained only 0·85 kg/day. Carcass quality of animals given dried grass was significantly lower than of those given the barley diet.

4. Calorimetric trials were made using two herbages from the first harvest (501, 532 kg N/ha) and all four herbages from the third harvest. In each of the six experiments three sheep were each given three amounts of a herbage, and in addition were fasted. Fifty-four calorimetric observations each lasting 5 days and eighteen fasting metabolism measurements were made.

5. With both 1st and 3rd harvests, methane energy losses fell and urinary energy losses increased with the level of N fertilization. Faecal energy losses were little affected by fertilizer application and the metabolizable energy (kcal/g D.M.) was 2·8 (11·7 kJ/g) for 1st harvests and 2·6 (10·9 kJ/g) for 3rd harvests. There was a slight decline in metabolizable energy/g D.M. with N application for the 3rd harvests.

6. The net energy values of the grasses for maintenance were 1·99 kcal/g D.M. (8·4 kJ/g) for the 1st harvested material and 1·84 kcal/g D.M. (7·7kJ/g) for the 3rd harvests. Net energy values for fattening, however, were 1·28 kcal/g D.M. (5·4kJ/g) for 1st harvests and 0·87 kcal/g D.M. (3·6kJ/g) for 3rd harvests. There were no significant effects of level of N fertilization.

7. The poorer nutritive value for fattening of the 3rd harvested grass, corresponding to an efficiency of utilization of metabolizable energy of only 33%, was contrary to prediction from equations relating nutritive value to either chemical composition or to metabolizable energy. The results of the calorimetric work, however, agreed with those of the feeding trial with cattle.

8. Combination of the results of the various trials showed that it was possible to obtain 1400 kg live-weight gain/ha from a system of husbandry based on high fertilizer use and artificial drying of herbage. With a barley system a maximal output/ha would be less than half this amount.
The growth and yield of tall and short sorghums in Nigeria
Authors: Goldsworthy P. R.
Published: March 2009

A Nigerian, long-season, sorghum produced 15 tons of dry matter/acre in about 155 days, but the grain yield was small (2000 lb/acre or 2242 kg/ha) because only part of the dry matter formed after heading went into the grain. In contrast, an American, short-season hybrid which formed only from one-half to one-third as much dry weight as Farafara, gave over 4000 lb of grain/acre (4484 kg/ha) in 100 days. A Nigerian sorghum of intermediate height and a long-season hybrid, produced by crosses between Nigerian varieties and an American, short-season sorghum, gave larger yields than the tall variety because they formed more heads/unit area and more grains/head.

Crop growth rates of the three long-season sorghums sown in June increased to a peak in July, but declined sharply to very small values in September, and then increased again very rapidly at the end of September as heads emerged. The most important factors causing the decline were a decrease in radiation and a loss in dry weight from decay and detachment of dead leaves. An increase in radiation at the end of September and developmental changes associated with head emergence contributed to the increase in growth rates just before heading.

A large proportion of the dry weight formed after heading in Farafara accumulated in the stem but a smaller proportion in the other long-season variety and the longseason hybrid. There was an inverse relationship between the increase in stem weight and the yield of grain. For large grain yields, sorghums are needed that will produce heads with sufficient grains to accommodate all the assimilate that the leaves produce at the end of the rains when crop growth rates are increasing.
Nitrogen requirement of cereals: 2. Multi-level nitrogen tests with spring barley in south-western England
Authors: Needham P. , Boyd D. A.
Published: March 2009

Seventeen experiments with spring barley testing seven amounts of nitrogen were made on commercial farms in Somerset, Devon and Cornwall between 1965 and 1968. Crop measurements and determinable site factors were only partially successful in accounting for differences between sites and between years in optimal N and efficiency of N use below optimum.

The actual optima were found to differ considerably from predicted N requirements based on past cropping and summer rainfall.
The effects of a wide range of nitrogen rates on some chemical constituents of the herbage from perennial ryegrass swards with and without white clover
Authors: Reid D. , Strachan N. H.
Published: March 2009

Selected herbage samples from a 6-year experiment in which nitrogen rates between 0 and 897 kg/ha were applied annually on perennial ryegrass swards were analysed for nitrate-nitrogen, true-protein and non-protein nitrogen, water-soluble carbohydrate, potassium and sodium content and for amino acid composition. The nitrate-nitrogen content of the herbage increased with increasing nitrogen rate from 224 kg/ha upwards, but the potentially toxic level of 220 mg/100 g dry matter was not reached until the annual nitrogen rate was about 560 kg/ha. On average, at the 897 kg nitrogen/ha rate the non-protein nitrogen content had increased to 27·5% of the total nitrogen yield, and 40·3% of the non-protein nitrogen yield consisted of nitrate nitrogen. Nitrate content was shown to be a sensitive indicator of the level of nitrogen nutrition of the herbage, the optimum nitrogen rate for dry-matter production coinciding with a nitrate-nitrogen content of approximately 100 mg/100g dry matter. The amino acid composition of the herbage varied little with either the rate of nitrogen or the date of cutting. It was demonstrated that, on average, a 1% unit increase in the crude-protein content of the herbage was accompanied by a 1% unit decrease in the carbohydrate content. The sodium content of the herbage increased with increasing nitrogen rate up to between 448 and 560 kg/ha, but the potassium content showed little variation.
The effect of three different growth rates on some offal components of cattle
Authors: Murray D. M. , Tulloh N. M. , Winter W. H.
Published: March 2009

This paper describes the effect of three different growth rates on some offal components of Angus cattle. The growth rates were: high (H, 0·8 kg/day), low (L, 0·4 kg/day) and high-maintenance (HM, 0·8 kg/day followed by a period during which body weight was held constant).

Equations are presented which enable the weights of the offal components to be calculated within the body weight range 300–440 kg.

For most tissues, weights in the H group were greater than in the L and HM groups and included: liver, rumen-reticulum, small intestine and the total alimentary tract. Weight of fat trimmed from the rumen-reticulum, omasum, large intestine and total alimentary tract was also greater in the H than in the L and HM groups. The reverse situation held for head, feet and tail and the spleen.

In spite of these differences between groups in weights and composition of offals, the carcass composition in all groups was similar (Murray, Tulloh & Winter, 1974). It appears that, at a given body weight, changes in the offals may buffer the carcass against change in composition when cattle are exposed to different growth patterns.
The effects of constant and varying heights of cut on the yield of Italian ryegrass (Lolium multiflorum Lam.) and perennial ryegrass (Lolium perenne L.)
Authors: Ollerenshaw J. H. , Hodgson D. R.
Published: March 2009

Three constant and four variable heights of cutting were applied to swards of Italian ryegrass (Lolium multiflorum Lam.) cv. Aberystwyth S. 22 and perennial ryegrass (Lolium perenne L.) cv. Aberystwyth S. 23 for a period of 2 years. The treatments were initially given in the seeding year of the Italian ryegrass swards and first harvest year of the perennial ryegrass. The same swards were used throughout the duration of the two experiments. The three heights of cutting 3, 6 and 9 cm were defined by the mean lengths of tiller remaining after defoliation with a flail harvester.

The yield of dry matter (D.M.) was relatively low from Italian ryegrass cut repeatedly to 3 cm because many plants died. Higher yields were obtained by cutting repeatedly to 6 or 9 cm but only when the grass at the end of the season was cut to 3 cm. Italian ryegrass produced more herbage by variable than constant heights of cutting, especially when a lax cut occurred in mid-summer.

Perennial ryegrass gave higher yields of D.M. by constant low than high cutting, but there were no differences in yield when the constant high cut swards were closely defoliated at the end of each season. More herbage was produced by variable than constant heights of cutting in the second year, especially when several lax cuts occurred in the variable height of cut treatments.

As perennial ryegrass had a very prostrate growth habit in swards which received several close cuts tillers were not defoliated too severely. In contrast, Italian ryegrass remained erect in growth habit even in swards which were closely defoliated and thus tillers were cut more severely than those of perennial ryegrass. The need to measure accurately the actual lengths of tillers after defoliation is emphasized in height of cutting treatments.
The relationship between disease symptoms and parasite growth in bacterial blight of cotton
Authors: Brown S. J.
Published: March 2009

Lesion development and growth of Xanthomonas malvacearum (E. F. Smith) Dowson were followed in seedlings of different cultivars of cotton (Gossypium hirsutum L.) after inoculation of hypocotyls. There was a close relationship between numbers of the parasite and length of hypocotyl lesion. Disease development could be accurately determined by measurement of lesion length from 2 to 3 days after inoculation until growth of the parasite ceased. Growth patterns of the parasite in vivo took the form of a distinct period of exponential (phase 1) growth followed by relatively little, if any, further increase in numbers (phase 2 growth). The duration of phase 1 growth was related to host resistance and environmental factors.
Intercropping maize and sorghum with soya beans
Authors: Mohta N. K. , De R.
Published: March 2009

Field trials were made in the rainy seasons of 1970–4 at the Indian Agricultural Research Institute, New Delhi, to evaluate several systems of intercropping maize and sorghum with soya beans. Maize yields were not affected by intercropping with soya beans but sorghum yields were reduced. Though the yield of soya beans when intercropped was less than that of a sole crop, the combined grain yield of the two crops in an intercrop was more than the individual components. Land equivalent ratio (LER) increased to a maximum of about 48 and 31% by intercropping maize and sorghum with soya beans compared with the cereal sole crops. Maize rows planted 120 cm apart and intercropped with two rows of soya beans or sorghum planted 90 cm apart intercropped with one row of soya beans proved to be the best intercropping pattern.
The estimation of parameters by least squares from unbalanced experiments
Authors: Finney D. J.
Published: March 2009

Data from experimental and observational studies, in agriculture as in many other contexts, are often unbalanced in respect of important classifications. Treatments may be unequally replicated, some combinations of factors may be omitted, animals may die for reasons unconnected with an experiment. Unless means are adjusted in some manner that eliminates disturbance from unequal representation of different categories, comparisons between treatments may be thoroughly misleading. Optimal procedures for the simpler situations have been familiar to statisticians for a long time. They have been little used by other scientists analysing their own data, in part because of the computational labour and in part because their nature has not been properly understood.

Modern computing power removes all excuse for the retention of methods that may be actively misleading because they bias summaries of data, or that are at best inefficient in their failure to estimate comparisons as precisely as is possible. The only remaining barrier is the mistaken belief that good methods are either so complicated that they can be comprehended only by professional statisticians or so devious that truth is destroyed rather than exhibited. This paper attempts to show good methods as inherently rational, to explain their main properties, and to illustrate them on examples small enough for the processes to be clear. The paper neither expounds statistical theory nor instructs in computing practice.
An evaluation of body size as related to weight of three West African breeds of cattle in Nigeria
Authors: Buvanendran V. , Umoh J. E. , Abubakar B. Y.
Published: March 2009

Body measurements and weights of animals of varying ages were recorded in White Fulani (Bunaji), Sokoto Gudali and N'dama breeds of cattle. Chest girth accounted for 86–96% of the variation in body weight in the three breeds. The linear regression coefficient of weight on chest girth in the N'dama differed significantly from the other two breeds. Within each breed, the regression coefficient of young animals was lower than those of older groups. The variables that contributed most to improving the prediction of weights when added to chest girth were rump length and body length. Animals with low body condition scores had lower regression coefficients of weight on chest girth than those with high scores.
Effects of adding plant nutrients to the gel carrier used for fluid drilling early carrots
Authors: Finch-Savage W. E. , Cox C. J.
Published: March 2009

Phosphates and nitrate were added to the gel used for fluid drilling without affecting its properties as a seed carrier. The addition of monosodium phosphate promoted early seedling growth but at concentrations higher than 30 g/1 it became phytotoxic. Nitrate added to the gel reduced plant growth and decreased the number of seedlings emerging. Ammonium phosphate was found to be an effective addition to the gel and could be used in the form of a proprietary liquid ammonium polyphosphate fertilizer. The earlier emergence of fluid-drilled germinating seeds and the enhanced growth brought about by phosphate addition to the gel increased plant size compared with that of the dryseeded controls. The results are discussed in relation to the early production of marketable-size carrots.
Comparisons between combine-drilling and broadcasting muriate of potash for spring barley
Authors: Widdowson F. V. , Penny A. , Williams R. J. B. , Cooke G. W.
Published: March 2009

1. Twelve experiments were carried out in Bedfordshire and Hertfordshire in 1955–57 to compare combine-drilling and broadcasting muriate of potash for barley. Ordinary mineral soils were used and only one contained more than 25% of calcium carbonate.

2. On average of all the experiments in each year 0·25 cwt. K2O/acre drilled with the seed gave higher yields than 0·5 cwt. K2O/acre broadcast and worked into the seedbed. The average extra yields of barley from combine-drilling, as compared with broadcasting, were 1·2 cwt./acre when 0·25 cwt. K2O/acre was applied and 2·0 cwt./acre of grain when twice as much K2O was given. In twenty-one of the total of twenty-four comparisons drilling gave higher yields than broadcasting and in onethird of these comparisons the effects were significant. Combine-drilling gave higher average yields of straw than broadcasting.

3. The average level of response was not great, the low and high rates of combine-drilled muriate of potash increasing yields by 13 and 16%, respectively. Only a small proportion of the applied potassium was taken up by the crops; apparent recoveries by grain plus straw averaged 11% of the light-drilled dressing and 8% of the heavy dressing.

4. The level of response to potassium varied from year to year, but was much greater on average in the 1955 experiments than in 1956 and 1957. There was no close relationship between the degree of response and values for dilute hydrochloric-acidsoluble potassium or exchangeable potassium in the soils used.
Field experiments on phosphate fertilizers. A joint investigation
Authors: Cooke G. W. , Widdowson F. V.
Published: March 2009

The results of about ninety field experiments carried out over three years to test dicalcium phosphate, nitrophosphate, ammoniated fertilizer and Gafsa rock phosphate are summarized and discussed. Soils with pH values of 6·5 and below are listed as ‘acid’, those with higher pH values as ‘neutral’. All comparisons were made in terms of fertilizers supplying the same total amounts of phosphorus.

Dicalcium phosphate dihydrate gave approximately the same yields as superphosphate for potatoes (both on acid and on neutral soils) and for grass, kale and barley. In one group of swede experiments mostly carried out in the north-east of the country dicalcium phosphate was inferior to superphosphate, but it was equal to superphosphate in another group of swede experiments, most of which were on acid soils in wetter areas.

A nitrophosphate made in England on pilot-plant scale was consistently inferior to superphosphate for barley, potatoes and swedes.
The effects of oxalate in tropical grasses on calcium, phosphorus and magnesium availability to cattle
Authors: Blaney B. J. , Gartner R. J. W. , Head T. A.
Published: March 2009

Cattle were fed four hays in mineral balance experiments. Two of the hays (Cenchrus ciliaris and Setaria sphacelala var. sericea) contained 1·8 and 1·3% total oxalates and provided above- and below-maintenance intakes of calcium respectively. These grasses contain calcium oxalate crystals. The other two hays (Aristida spp –Bothriochloa spp. mixture and Triticum aestivum) contained 0·1% oxalates, and also provided above- and below-maintenance intakes of calcium. The absorptions of calcium from the hays providing above-maintenance intakes were 51% for the high and 57% for the low oxalate hay. At below-maintenance intakes, the cattle were in negative calcium balance and calcium absorptions were 52% for the high and 64% for the low oxalate hay. While in negative calcium balance the cattle were given single doses of calcium oxalate, followed by single doses of either limestone or rock phosphate. The cattle fed S. sphacelata hay absorbed sufficient calcium from calcium oxalate to achieve positive calcium balance, although the amount absorbed was only 52% of that absorbed from limestone. The cattle fed T. aestivum hay also absorbed calcium from calcium oxalate, but in insufficient amount to result in a positive calcium balance. The amount absorbed was 47% of that absorbed from rock phosphate. The results demonstrate that in tropical grasses containing calcium oxalate crystals, the availability of calcium is about 20% lower than it is in grasses containing little oxalate. Adaptation to oxalate may improve the ability of the rumen to utilize calcium oxalate. It is suggested that the availability of calcium to cattle grazing tropical grasses should be considered to be a maximum of 50%. Neither magnesium nor phosphorus absorptions from tropical grasses were affected by oxalate.
The conversion of pasture to milk: the effect of stocking rate and concentrate feeding
Authors: Hancock John
Published: March 2009

1. An experiment is described in which the effect of the level of nutrition, as determined by stocking rate and the use of supplementary concentrates, on milk yield and efficiency of production was studied.

2. Three levels of nutrition were used: Treatment (A)—one milking cow per acre plus 1 lb. of concentrate mixture for each 5 lb. of milk produced. Treatment (B)—one milking cow per acre—no concentrates. Treatment (C)—one milking cow per sixtenths of an acre—no concentrates.

3. Fifteen sets of identical twins were used per year over an experimental period of 3 years. The groups were rotationally grazed with a daily shift to a fresh pasture on a 14-day rotation. Ninety complete lactations were available for analyses.

4. The A cows produced 45% and the B cows 16% more f.c.m. than the C cows. Per unit area, however, the C treatment produced 30% more than the B.

5. Significant differences in milk composition were established, but these were of much smaller magnitude than those in milk yield.
Losses in the conservation of grassland herbage as molassed and metabisulphite silage in lined trench silos
Authors: Brown W. O. , Smyth V.
Published: March 2009

A conservation experiment is described in which a comparison of the nutrient losses and quality of sodium metabisulphite silage and molassed silage is made. The loss of dry matter in molassed silage is shown to be 3·5% higher than in metabisulphite silage.

The lactic-acid content of metabisulphite silage is found to be some 40% less than that of molassed silage.

The results obtained are discussed in relation to published work on conservation by metabisulphite and to the practical application of the method.
Nitrogen fertilizers for spring barley and wheat
Authors: Widdowson F. V. , Cooke G. W.
Published: March 2009

1. Ten experiments on spring barley (mainly Proctor) and four on spring wheat (mainly Atle) in 1954–6 compared 0·25 and 0·5 cwt. N/acre (as ammonium sulphate) when drilled with the seed, with dressings broadcast before sowing. Tests were also made of ‘Nitro-Chalk’ dressings given in mid-May. In heavier split applications seedbed dressings were supplemented by top-dressings of 0·5 cwt. N/acre.

2. Barley gave much larger average responses than wheat. For barley combine-drilling 0·25 or 0·5 cwt. N/acre gave consistently larger yields than broadcasting the same nitrogen dressing on the seedbed; for wheat combine-drilling gave slightly higher yields at the high rate of dressing only.

3. For both crops 0·5 cwt./acre of N drilled with the seed was almost sufficient for maximum yields, but where only 0·25 cwt. N was applied at sowing a mid-May top-dressing of 0·5 cwt. N/acre gave higher yields.

4. At most centres May top-dressings of ‘Nitro-Chalk’ gave lower yields than equivalent ammonium sulphate drilled with the seed. Yields were often reduced by lodging on plots which received seedbed dressings plus top-dressing or the heavier rates of top-dressing alone; these treatments also reduced the quality of the grain. Combine-drilled or broadcast seedbed dressings did not cause serious lodging or reduce grain quality.

5. 0·25 or 0·5 cwt. N/acre broadcast on the seedbed or combine-drilled had little effect on the percentage of nitrogen in the grain; equivalent topdressings in mid-May consistently increased nitrogen content. Seedbed dressings plus top-dressings supplying heavier total quantities of nitrogen continued to increase nitrogen percentage in grain without giving any increase in yield.
Estimation of the body chemical composition of live cattle varying widely in fat content
Authors: Little D. A. , McLean R. W.
Published: March 2009

Following the measurement of tritiated water (TOH) spaces, 31 cattle were slaughtered and chemically analysed in this study. They included several breeds, both females and castrate males, and were of varied nutritional history. Their body-fat content ranged from 4 to 21% of fasted live weight.

Total body water (including the water in the gut contents) was reliably estimated from TOH space, measured after allowing an overnight 16 h waterless fast for TOH equilibration. Following this regime, residual D.M. in the gut contents amounted to 1·75% of fasted live weight. The relationships of body fat to body weight, and body fat to body water when both were expressed as percentages of body weight, were too variable to be used in any predictive fashion. Equations were derived, using fasted live weight, allowing the accurate estimation in vivo of the quantities of the chemical components in the whole body (i.e. total body minus D.M. in gut contents).

It was demonstrated that the sum of total body water and total body fat constituted virtually 80% of total body tissues, and that total body protein closely approximated 80% of the fat-free dry matter, in cattle varying widely in body condition. These relationships constitute the physiological basis of the equations presented.

Comparable principles appear to apply to sheep, and a range of other mammalian species.
Ripening in maize: interrelationships between time, water content and weight of dry material in ripening grain of a flint × dent hybrid (Inra 200)
Authors: Bunting E. S.
Published: March 2009

Results are reported of ripening studies with maize (var. Inra 200) at Oxford, 1967–9. Sowings were made in late April or early in May, and crops grown at a standard density of 7–2 plants/m2. Areas were provided with cloche protection, for a 4- to 5-week period from time of sowing, to produce material for studies of the effects of flowering time on ripening patterns. From plants of known flowering date collections of 30–40 ears were taken at intervals from 30 until 100+ days after silking.

Information is presented on water content, grain dry weight and number of grains/ear at the various times of harvest. Asymptotic, polynomial and inverse-polynomial regression models have been fitted to the data to elucidate the interrelationships between time (measured from date of silking), grain water content and grain dry weight.

In plants flowering in mid-July grain continued to increase in dry weight until water content was reduced to 35 %, whereas in plants flowering early in August maximum dry weight was attained at a water content of around 40 %.Maximum dry weight of grain was approximately 10% higher in the earlier flowering plants; the corollary is that in the marginal areas of maize grain production in England maturity in such varieties as Inra 200 is often imposed by the environment with a consequent loss in potential yield.

In the early flowering plants, the time taken from silking to reach the harvestable stage of 40 % grain water content was 69 d in 1967, 79 d in 1968 and 64 d in 1969. Rate of water loss from the grain during ripening was closely related to prevailing air temperatures. In the later flowering plants, differing by an average of 11 d in time of silking, 8 days longer was required for grain to be reduced to 40% water content, giving an average difference of 19 days in permissible dates of harvest.

The results suggest that, in varieties of similar ripening pattern to Inra 200, an advance of about 7 days in flowering time is required to establish the maize grain crop beyond its present confines in south-east England.
The use of internal markers to estimate herbage digestibility and intake: 2. Indigestible acid detergent fibre
Authors: Penning P. D. , Johnson R. H.
Published: March 2009

Digestibility trials were carried out using wether sheep, to determine the organicmatter digestibility of several forages. Acid detergent fibre (ADF) was isolated from samples of feed and faeces, incubated in buffered cellulase solution, and the ash-free residue remaining (IADF) was used as an internal marker to estimate the organicmatter digestibility (OMD) of the feeds. Estimates of the OMD value of the samples were also made using the standard in vitro digestibility technique.

IADF had reached a constant value after incubation for 4–5·5 days and predicted OMD more precisely than the in vitro digestibility technique.

It is concluded that IADF is a suitable internal marker and predicts OMD well. However, more work is required to test this technique over a wider range of herbage species and digestibilities.
Resistance of cow-pea pods to Callosobruchus maculatus Fabr
Authors: Fatunla T. , Badaru K.
Published: March 2009

Four bruchid-resistant and four susceptible cow-pea cultivars and their F2 crosses were evaluated for oviposition, egg hatching and emergence scores of cow-pea weevils, Callosobruchus maculatus Fabr.

Whereas oviposition and number of eggs hatched were normally distributed, percentage of eggs hatched was not. For percentage weevil emergence, the F2 progenies with susceptible parents as females had a different distribution from that of their reciprocals with resistant parents as females.

Preferential oviposition was not observed among the parents and their F2 progenies. Resistance was observed at the egg hatching and weevil emergence stages. Percentage of eggs hatched was significantly and positively associated with percentage weevil emergence.
A study of the lactation and growth of hill sheep in their native environment and under lowland conditions
Authors: Owen J. B.
Published: March 2009

1. A method is described suitable for the estimation of the milk yield of sheep under natural grazing conditions.

2. The yields obtained from Welsh Mountain sheep in two environments are shown.

3. A close but diminishing relationship is shown to exist between the milk yield of the ewe and the growth of the lamb. Evidence is given of the effect of milk yield at later stages.

4. The estimation of the ewe's milk yield from the weight of the young lamb is discussed. These estimates are used in conjunction with actual milk records in the present study.

5. The ewe's milk yield is shown to be significantly related to nutrition, body weight, udder size and the lamb's birth weight.

6. The relation of milk yield to weight gain during lactation, fleece weight and fleece type were mainly non-significant.

7. From the limited data available, it seems that milk yield has a fairly high repeatability and heritability.
A note on the digestibility of Nardus stricta
Authors: Thomas Brynmor , Fairbairn C. B.
Published: March 2009

Davies (1941) has estimated that there are nearly 1,300,000 acres of hill land in England and Wales upon which the white bent or wire grass (Nardus stricta) is predominant, or constitutes a high proportion of the ground cover. From this estimate, which is probably a conservative one, it follows that approximately 24% of the rough grazings of this country are wholly or largely Nardus pastures. The opinion that Nardus is of almost negligible grazing value is widely held. Smith (1918) has said that no stock will graze it by preference, although he admits that a certain amount of the foliage is eaten in early summer. Pearsall (1950), Fenton (1936) and Stapledon (1937) have expressed very similar views. Wallace (1917) regarded this grass in a more favourable light and, while he certainly did not rank it with the best moorland grazing plants, stressed its value in winter. The truth is that these opinions are based almost wholly on observation and are supported by very little evidence on nutritive value. Analyses on conventional lines have been made by Kinch (1884), Evans (1927), Fagan & Watkins (1934) and Thomas & Dougall (1948). Thomas & Trinder (1947) have made a detailed examination of the ash. Digestibility data appear to be nonexistent; without such data any worth-while estimate of nutritive value is almost impossible. In view of the existence of very large areas on which little other than Nardus is available for the sustenance of hill sheep, it would seem desirable to attempt such an estimate. It was therefore decided to carry out digestibility trials in which the grass, cut at two stages of growth, was fed to sheep of a hill breed.
Blood-urea concentration in relation to protein utilization in the ruminant
Authors: Lewis D.
Published: March 2009

1. It has been shown that under a given feeding régime the concentration of blood urea in the sheep is constant.

2. Changes in the diet lead to different levels of blood-urea concentration which can be correlated with different rumen-ammonia concentrations; the change in blood-urea concentration follows increases or decreases in rumen ammonia after a delay period of 4–8 hr.

3. Fluctuations in blood-urea concentration in the sheep are not primarily due to changes in the overall nitrogen intake.

4. It is suggested that these findings might form the basis of a supplementary test in assessing the value of the protein in a foodstuff for ruminants.
Pyrophosphate as a source of phosphorus for maize in some acid soils from southern Nigeria
Authors: Uzu F. O. , Udo E. J. , Juo A. S. R.
Published: March 2009

Hydrolysis and sorption reaction of pyrophosphate (PP) in soils and uptake of PP by maize were studied using some acid soils from southern Nigeria. Rate of hydrolysis varied with the soil type, and half-lives of hydrolysis ranged from 10 to over 40 days in unsterilized soils and more than 40 days in all cases when the soils were sterilized. An appreciable fraction (over 40%) of the added PP resisted hydrolysis, the effect being more pronounced in the sterilized soils.

Sorption of both PP and orthophosphate (OP) by soils followed the Langmuir isotherm. The adsorption capacity and bonding energy index for all soils were greater for PP than for OP.

A short-term glasshouse experiment showed that PP was as good as OP as a source of P to maize. When the soils were limed to pH 6, PP appeared to be superior to OP.
The phosphorus cycle in pig slurry measured from 32PO4 distribution rates
Authors: Gerritse R. G. , Zugec I.
Published: March 2009

The rate of isotopic distribution of labelled phosphorus, added as H332PO4, between inorganic and organic phosphates and phosphates contained in micro-organisms was measured in pig slurry. Incorporation of 32P in all these phosphates occurred quickly in both aerated and non-aerated pig slurry. On the basis of a simplified model, turnover times for phosphorus were calculated to be of the order of 10–20 weeks for both non-aerated and aerated pig slurry.

Pig slurry contains 1–2% P (of dry matter) of which 10–30% is in organic molecules and 2–3% is in micro-organisms. About 10–20% of the organic phosphates is in solution, amounting to 10–20 mg P/l. The concentration of inorganic P in solution is of the order of 10–100 mg/1 though, at low Ca/P ratios in the feed, can be as high as 1000 mg/1.

Organic phosphates in solution in pig slurry are of high molecular weight and probably consist of DNA complexes with polyphosphates, Ca and (if used in the feed) Cu.

It is concluded that all organic phosphates in pig slurry are of microbial origin and that the feed composition has little influence on the organic phosphate content of the
slurry.

Arguments for application of the results to pig slurry in general and to wastes from
other animals are given.
Effects of two paths of live-weight change on the efficiency of feed use and on body composition of Angus steers
Authors: Foot Janet Z. , Tulloh N. M.
Published: March 2009

This paper describes the effect of two paths of weight change on the total feed consumed and on body composition at slaughter of Angus steers. The treatments were: a 15% weight loss from 330 kg live weight, at 0·5 kg/day for 100 days, followed by recovery to 330 kg on ad libitum feed intake (WL/WG group), and constant weight at 330 kg for the same length of time as corresponding paired animals in the WL/WG group took to complete their treatment (constant-weight group). There were six animals in each group and they were slaughtered when the WL/WG steers reached 330 kg. At the beginning of the experiment four animals (preliminary group) were slaughtered at 330 kg.

Intakes of feed were recorded and measurements of apparent dry-matter digestibility were made at intervals. Chemical analyses were carried out on the right side of each carcass and on the other components of the body.

The mean total intake of the WL/WG group was 12% less than that of the constant-weight group. The daily dry-matter intake in the constant weight group decreased from 5·9 kg to 4·4 kg during the experiment.

The time taken for the WL/WG steers to regain the 50 kg weight loss varied from 30 to 68 days. Their intakes at this time and their growth rates were similar to those that they experienced when they grew to 330 kg for the first time.

Apparent digestibility varied between animals but was not influenced by treatment. The constant-weight group were fatter than the WL/WG group at slaughter and had heavier carcasses, both differences being significant (P < 0·05). The difference between groups in empty body weight was not significant. Animals from the final slaughter groups had significantly heavier heads and feet and a higher ash content than the younger steers of the preliminary group. Liver weights were reduced by nutritional restriction and did not fully recover in WL/WG steers.
Morphology and genetics of two gene markers, ‘Swollen stem base’ and ‘Hastate leaf’ in cowpea, Vigna Unguiculata (L) Walp.
Authors: Ojomo O. A.
Published: March 2009

Two gene markers were observed among cowpea breeding lines in Ibadan, Nigeria. One is the swollen stem base which is due to a larger quantity of phloem parenchyma in the bottom part of the stem below the first primary leaf than in the normal stem. It is inherited as a simple dominant trait and the symbol Sw is suggested. The other is the hastate-leaf which is expressed as extremely narrow trifoliate compared with the normal. It is inherited as a simple dominant trait and the symbol Ha is suggested. Dominance may not be complete in both cases as variable expressions of the marker genes were observed in F2. The effects of the marker genes on yield and other characters are currently being investigated.
The effects of breed, breeding system and other factors on lamb mortality: 4. Factors influencing the incidence of infectious and non-infectious diseases as causes of death
Authors: Macleod N. S. M. , Wiener G. , Woolliams Carol
Published: March 2009

The incidence of various infectious and non-infectious diseases as causes of death in lambs up to 8 months of age was studied in relation to breed, inbreeding and other factors. The data from an upland grazing flock covered 6 years and involved the Scottish Blackface, Cheviot and Welsh Mountain breeds and the crosses among them.

Infectious and non-infectious diseases were directly responsible for almost a quarter of the mortality and their presence contributed to many more deaths. The organisms mainly responsible were Escherichia coli, Pasteurella spp. and Fusobacterium necrophorum.

The incidence of infectious diseases in general and enteritis in particular varied significantly between the breeds and was lower in the cross-breds than in the purebreds. Variation between the breeds in the incidence of non-infectious diseases was statistically significant only in respect of digestive upsets for which there was a similar ranking of breeds to that for infectious disease.

Inbreeding of the lamb (25–59%) significantly increased the incidence of infectious diseases, especially respiratory diseases, but not of non-infectious diseases. There was little difference between singles and twins in susceptibility to disease. The lower the birth weight of the lamb the greater the risk, particularly of non-infectious disease.
Prediction of carcass composition from carcass conformation in cattle
Authors: Bass J. J. , Johnson D. L. , Colomer-Rocher F. , Binks G.
Published: March 2009

Conformation of carcasses from 98 steers from ten different sire breeds was classified according to two visual systems and two objective measurements, which were related to both commercial and dissected carcass composition of their hindquarters. The visual carcass conformation systems, unlike the objective systems, accounted for only a small percentage of the variation in some carcass traits after adjusting for the weights of the right hindquarter and of dissected fat from that hindquarter. Of the carcass conformation systems tested, the objective measurement of area appears to be the best predictor of carcass traits, with the variation in the weight of meat being reduced by 13·4% (P < 0·001) by the inclusion of area measurements. It is suggested that an objective assessment of carcass conformation might be of use in a national carcass classification or grading system.