The activities of some enzymes that regulate the gluconeogenic-glycolytic pathway were measured in sheep liver during late pregnancy, at three stages of lactation and after the lambs were weaned. Of the gluconeogenic enzymes, glucose-6-phosphatase and phosphoenolpyruvate carboxylase activities were unchanged throughout pregnancy and lactation and were similar to the values for non-breeding ewes. The activity of fructose diphosphatase increased 2 times and that of pyruvate carboxylase increased 5–7 times during late pregnancy and in early lactation.

In the glycolytic sequence phosphofructokinase activity declined by about 50% during lactation. Pyruvate kinase activity declined by about 40% at the end of pregnancy but throughout lactation it was similar to the value for non-breeding ewes. Hexokinase activity was very low in all animals.

In soya beans (var. 3H55F4/149/1) grown in Tanzania, the total dry matter per plant, pod weight/stem weight, shelling percentage, number of nodes per plant, number of pods per plant, percentage number of nodes with pods, number of filled pods per plant, number of branches per plant, and grain weight from side branches decreased with increase in plant density from 74 to 111, 222, and 444 thousand plants per hectare. Grain yield per hectare decreased by 38, 51, and 72% respectively with the increases in plant population, but yield of total dry matter per hectare showed a significant increase with density. Crop growth rate increased with increasing leaf area, which in turn increased with increasing plant density. Relative growth rate, however, decreased with rising population. Over the range of the densities studied grain yield was positively related to number of side branches but negatively related to dry-matter production, leaf area duration and percentage of light intercepted. The proportion of dry matter accumulated in the pods and side branches decreased with increase in population, whereas the proportion accumulated in the main stem increased. Light seems to be the major factor controlling grain yield in this variety of soya bean, low light intensity under the plant leading to a reduction in the number of side branches, number of pods per plant and number of nodes with pods.

Fifty-two genotypes of rice bean (Vigna umbellata Thunb. (Ohwi and Ohashi)), an under-cultivated crop, were evaluated in the rainy (kharif) seasons of 2001, 2002 and 2003 in the North Eastern Hill Region, India to select suitable genotypes for cultivation in the North Eastern Hill region and to identify promising parents for hybridization programmes. The germplasm studied comprised 44 Indian and eight foreign genotypes. A wide range of variability was observed for eight characters studied (plant height, number of branches/plant, stem thickness, pod length, number of seeds/pod, 100-seed weight, pod weight/plant and seed yield/plant). Number of days to mid-flowering and number of days to maturity showed little variation. High heritability (0·58) and high genetic advance (0·53) were observed for 100-seed weight, high heritability (0·93) and moderate genetic advance (0·37) for seed yield/plant, and high heritability (0·60) and low genetic advance (0·13) for number of days to mid-flowering. Since the main aim in rice bean breeding is to develop high yielding, early maturing genotypes with low plants, selection was based mainly on the mean performance of these three traits over the 3 years, as well as their stability. One of the genotypes, RBL 1, was very high yielding, although the yield was not stable across years. Another genotype, RBS 24, was very early maturing and had very short plants compared with the other genotypes studied. These two, along with several other genotypes selected, may be promising for a hybridization programme aiming to develop dwarf, early maturing genotypes with high yield. The best yielding genotypes, namely RBL 1, RCRB1-3 and IC 187911, may be recommended for cultivation in the shifting cultivation areas (Jhum) regions of North Eastern India.

The effects of varying static and changing moisture contents on mineralization of nitrogen after incubation (28° C.) for 3, 6 and 12 weeks were studied.

Mineral-nitrogen, accounted for entirely by nitrate, increased with increasing static moisture content up to 40-50% water-holding capacity (W.H.C). With further increasing moisture up to waterlogging, both mineral-nitrogen and nitrate decreased, the latter to negative values, indicating disappearance of nitrate originally present in the soil. Ammonia accumulated only at moisture contents above 50 % W.H.C. and its extent of accumulation increased with moisture content.

When soils with moisture contents of 10-50% W.H.C. during an initial 6-week period were changed to waterlogging for a second 6-week period, mineralnitrogen and nitrate accumulation decreased with increasing initial moisture in comparison with soils left at initial moisture contents for the second period.

Regression analysis was used to examine the relationship between the weight of water, protein and ash (kg) and fat-free empty body (FFEB) weight (kg) in data from six published and one unpublished experiment conducted in this laboratory. The analysis involved 201 sheep divided into 12 groups which were either in positive growth, weight stasis, weight loss or compensatory growth prior to slaughter. Each of the relationships between water, protein or ash and FFEB was linear and could be expressed by a common slope. Small (though statistically significant) differences in intercept were found between treatments. The following overall equations provide a simple description of the data:

water (kg) = 0·721 FFEB + 0·37, R.S.D. 0·18,

protein (kg) = 0·215 FFEB - 0·22, R.S.D. 0·16,

ash (kg) = 0·055 FFEB - 0·07, R.S.D. 0·09.

Published data for cattle were also examined and corresponding equations are:

water (kg) = 0·701 FFEB + 3·59, R.S.D. 2·6,

protein (kg) = 0·234 FFEB - 2·00, R.S.D. 2·3,

ash (kg) = 0·060 FFEB - 0·71, R.S.D. 1·8.

It is suggested that these equations could be used in computer simulation models of growth to calculate FFEB gain (or loss) from nitrogen balance.

Thirty-six Friesian and Friesian cross-bred cattle about 11 months old were fed to grow at the rates of 0·50 (low) and 1·08 (high) kg/day in a 12-week winter feeding period and then turned out on high quality pasture. For 12 weeks after turning out the ‘low’ and ‘high’ animals gained weight at 1·17 and 0·90 kg/day respectively. There was a negative correlation (– 0·57, P < 0·01) between winter and grazing live-weight gain.

On two occasions herbage intake was estimated. Average intake of ‘low’ animals was 12% higher than of ‘high’ animals although herbage digestibility, estimated from faecal N, was similar for the two treatments. Differences in live-weight gain on pasture between treatments were largely accounted for by differences in intake.

The low rate of winter growth did not have any significant effects on age at slaughter, carcass weights or grades attained by the restricted animals.

Five sugar beet experiments were made from 1964 to 1968 to measure yields of roots, of sugar and of tops from dressings of 0, 63, 126 or 188 kg N/ha. In 1964 and 1965 the sugar-beet tops were ploughed-in on all plots, but afterwards on only half of the total number of plots. Barley followed the sugar beet and was given 0, 41, 83 or 126 kg N/ha, in all combinations with the dressings of N to the sugar beet; grain was weighed and analysed for % N.

The maximum yield of sugar (8·24 t/ha) was with 126 kg N/ha. The yield of barley was increased greatly by giving it 83 kg N/ha, but not with more. When the barley was not given N, the residues of 126 kg N/ha for sugar beet increased grain yields by 0·17 t/ha, where the tops were carted away, and by 0·77 t/ha, where the tops were ploughed-in, but when the barley was given 83 kg N/ha, the residues increased yield negligibly (by 0·07 t/ha). Together the two sources of residue were equivalent to giving about 30 kg N/ha to the barley. Percentage N to the grain was consistently increased by both kinds of residue, but the grain never recovered more than 10 kg N/ha from them. So, sugar-beet tops had little residual value for barley, but offer a largely unused source of animal feed, rich in N.

Reserve energy accumulated before calving may make a contribution to total lactation yield. Random samples of cows which produced their first two lactations in the same herds were drawn from the progeny groups of three British Friesian sires whose milk yield proofs differed by a very significant amount. Regression of second lactation yield on first lactation, intervening dry period and length of lactation showed that the effect of the dry period was different in the three groups. Daughters of sire A with a contemporary comparison of + 374 ± 20 kgshowed a regression of 21·6 ± 7·8kg/day of dry period; sire B+174 ± 24 kg, 9·0 ± 5·2 kg/day; and sire C -174 ± 87 kg, 5·5 ±3·0 kg/day. If the dry period can be regarded as an opportunity for the cow to accumulate body reserves, a standard 60-day dry period could have made a contribution to total yield in group A of 25·5%, in group B of 12·2% and in group C of 8·1%. The argument for regarding these figures as approximate measures of the relative response to steaming up of the cows in the three groups is developed.

It was shown in previous work (Evans, 1958) that a cereal diet supplemented with 7% of white-fish meal supplied around 0·76% of lysine and 0·5% of methionine plus cystine. The addition of more pure l-lysine monochloride or dl -methionine to this animal-protein diet failed to bring about any significant improvement in the rate of growth, efficiency of food conversion or in the nitrogen retention of the pig, in the critical period between weaning and 80 lb. live weight. When the same cereal diet was supplemented by as much as 20% of ex. dec. ground-nut meal, however, the lysine content amounted to only 0·62% but the methionine plus cystine was 0·53%. On adding 0·2% l-lysine plus 0·2% dl-methionine to the 20% ground-nut diet the utilization of the nitrogen in the food was improved and the excretion of nitrogen in the urine was reduced. This finding was confirmed by means of a statistically designed growth trial, the daily rate of live-weight gain, improving from a mean value of 0·86 to 0·98 lb. following the addition of 0·2% of lysine and methionine, respectively, to the diet, the corresponding saving in meal consumption, between 35 and 80 lb. live weight, amounting to 16 lb. One group of ten pigs received a supplement of 0·2% of methionine only, and since it failed to show any improvement in performance over the control group it was concluded that 0·5% of methionine plus cystine must suffice to support satisfactory growth.

Data were collected from 549 Barki and Merino cross sheep during 1967, 1968 and 1969 to study the relation between kemp production and body vigour. The study also included the staple length and greasy fleece weight. The results showed that:

Age had a marked effect on the traits studied. Whereas kemp frequency (score) declined slightly as age proceeded, showing a significant reduction in the seventh shearing season, the staple length and fleece weight decreased after the second shearing season.

Differences due to sex, year and breed occurred, though the pattern differed in the different traits.

Kemp showed a highly significant correlation with birth and weaning weights, as indicating the animal vigour, and was negatively correlated with fleece weight.

Staple length was negatively correlated with birth and weaning weights and positively correlated with fleece weight.

Fleece weight was positively correlated to birth and weaning weights and negatively correlated to kemp score.

Kemp score in the Barki sheep was shown to be quite repeatablo (repeatability = 0·5).

Three methods of utilizing the natural Hyparrhenia grasslands for the dry-season nutrition of ranch cattle were tested in grazing trials. The feed regimes were:

(A) Late-cut veld hay plus aftermath grazing.

(B) The accumulated, seasonal growth of mature grass left as ‘standing hay’ for dry-season grazing.

(C) A combination of both practices in which half the area was cut for hay, and half left as ‘standing hay’. These treatments were compared with and without the feeding of supplementary protein.

Mature Hyparrhenia veld whether cut for hay or left as ‘standing hay’ was a stemmy, low-quality forage deficient in protein. The qualitative deficiency was such that all unsupplemented treatments were equally ineffective in preventing large cattle weight losses in the dry season.

The only significant treatment effect was that due to feeding a protein supplement. Otherwise, there were no differences between the three managements, i.e. there was no marked benefit from conserving forage as veld hay compared with in situ grazing of the standing grass.

The voluntary intake of veld hay was low; and with heifers, declined to negligible amounts. The feeding of supplementary nitrogen, either as protein or urea, increased the daily hay intake by 140%. As a result, a diet deficient in energy was altered into a productive ration, with consequent cattle weight gains.

Although the cattle preferentially sought-after, and grazed the aftermath from late-cut veld hay; its practical nutritional value was slight, and was not reflected in cattle weight gains.

Understanding the rumen microbial ecosystem requires the identification of factors that influence the community structure, such as nutrition, physiological condition of the host and host–microbiome interactions. The objective of the current study was to describe the rumen microbial communities before, during and after a complete rumen content transfer. The rumen contents of one donor cow were removed completely and used as inoculum for the emptied rumen of the donor itself and three acceptor cows under identical physiological and nutritional conditions. Temporal changes in microbiome composition and rumen function were analysed for each of four cows over a period of 6 weeks. Shortly after transfer, the cows showed different responses to perturbation of their rumen content. Feed intake depression in the first 2 weeks after transfer resulted in short-term changes in milk production, methane emission, fatty acid composition and rumen bacterial community composition. These effects were more pronounced in two cows, whose microbiome composition showed reduced diversity. The fermentation metrics and microbiome diversity of the other two cows were not affected. Their rumen bacterial community initially resembled the composition of the donor but evolved to a new community profile that resembled neither the donor nor their original composition. Descriptive data presented in the current paper show that the rumen bacterial community composition can quickly recover from a reduction in microbiome diversity after a severe perturbation. In contrast to the bacteria, methanogenic communities were more stable over time and unaffected by stress or host effects.

Rice has the lowest grain protein content (GPC) among cereals. Efforts have been made to improve GPC through the modified bulk-pedigree method of selection. A total of 1780 F8 recombinant lines were derived in the year 2013 from five different cross combinations involving two high-GPC landraces, namely ARC10075 and ARC10063, three high-yielding parents, namely Swarna, Naveen and IR64, and one parent, namely Sharbati, known for superior grain quality with high micronutrient content. Near-infrared spectroscopy was used to facilitate high-throughput selection for GPC. Significant selection differential, response to selection and non-significant differences between the predicted and observed response to selection for GPC and protein yield indicated the effectiveness of this selection process. This resulted in lines with high GPC, protein yield and desirable levels of amylose content. Further, based on high mean and stability for GPC and protein yield over the environments in the wet seasons of 2013, 2014 and the dry season of 2014, 12 elite lines were identified. Higher accumulation of glutelin fraction and non-significant change in prolamin/glutelin ratio in the grain suggested safe guarding of the nutritional value of rice grain protein of most of these identified lines. Since rice is the staple food of millions, the output of breeding for high GPC could have a significant role in alleviating protein malnutrition, especially in the developing world.

Investigations have been carried out in this department in recent years with the object of establishing the minimum protein requirements of the bacon pig. The results were recently summarized in this Journal (Woodman & Evans, 1948). The minimum protein standards recorded in that communication are consistent with the attainment of the maximum rate of growth compatible with the net energy content of the diet. The basal foods employed consisted throughout of 2 parts of barley meal and 1 part of middlings (fine bran), together with a little lucerne meal and minerals. Briefly, it was found that such a diet, when supplemented with 7% of white-fish meal, supplied the minimum amount of digestible protein required for the quickest possible rate of growth between weaning and 90 lb. live weight, when the level of feeding was such as is shown in the feeding chart (see Table 7). It was also found unnecessary to include any protein concentrate in the diet beyond 90 lb. live weight to ensure the maximum rate of growth over this later period. The requirements were based on the results of statistically designed growth trials, and were confirmed by nitrogen-balance determinations carried out in metabolism crates. It was found that nitrogen retention was just as favourable on the basal diet supplemented with 7% of white-fish meal as when the protein level was increased by feeding higher amounts offish meal.

The effect of P applications and native vesicular-arbuscular mycorrhiza (VAM) on the growth and P nutrition of red clover plants was studied in two acid hill soils with similar edaphic characteristics.

Mycorrhizal and non-mycorrhizal plants were compared under sterilized soil conditions. Plant growth increased on P addition in both soils, but the effect of mycorrhiza in improving drymatter production and P uptake was significant only in one of the soils. Fourteen and twenty-five mg/kg Olsen-P were needed in this soil to obtain the same yields by mycorrhizal and non-mycorrhizal plants, respectively. Results are explained in terms of a different effectiveness of the two fungal populations, and the possible effect of the soil sterilization process on percentage VAM infection is discussed.

In many areas of the world grazing cattle lose weight for part of the year because the dry standing pasture on offer is of poor quality and animals are unable to eat enough to meet their maintenance energy requirements. In countries where growth promoting anabolic agents are used, a perod of liveweight loss may coincide with the functional life of an implanted agent. There is evidence to suggest that diethylstilboestrol, a xenobiotic with oestrogenic activity, may increase maintenance energy requirements (Rumsey, Tyrrell & Moe, 1980). This has the effect of increasing the rate of live-weight loss under restricted submaintenance feeding conditions (Oltjen et al. 1973). One of the most common anabolic agents currently in use is the naturally occurring oestrogen, oestradiol-17β. However, its effects on energy requirements of animals either gaining or losing weight are unknown.

Wool samples from 47 Barki yearlings were taken from five positions during two years to study the variability in the fleece, the cause of variability and associations between different fleece traits. Statistical analysis has indicated the following significant points.

An antero-posterior gradient occurred in the different traits under study. When medullation was discarded, though it was of a low magnitude (3·9%), a reduction of 5·89% in the mean fibre diameter and of 18·33% in its standard deviation occurred.

The position most representative of the whole fleece varied with the trait. It is recommended to take three sampling positions forming a triangle, withers, mid-side and hip, to represent the Barki fleece.

The animals contributed the major part in the variability of mean fibre diameter (1), the standard deviation of fibre diameter (S.D.1), percentage medullation, mean fibre diameter after discarding the medullated fibres (2), the standard deviation of fibre diameter after discarding the medullated fibres (S.D.2), the contribution of medullation to the total variability, percentage fine fibres and percentage coarse fibres. The positions were the main contributor to the variability of percentage kemp fibres, staple length, medullation index and to a certain extent to that of the kemp score. The year played a significant part in the variability except for 2 and S.D.2.

The highest correlations with the standard deviation of fibre diameter were those of percentage medullation and kemp score. These three variables when considered separately accounted for 0·47, 0·35 and 0·31 respectively of the variability in S.D.

Equations were obtained to predict the standard deviation from both the mean fibre diameter and the percentage medullation and to predict the mean fibre diameter from the staple length and the kemp score. The coefficient of determination of the first set of equations ranged from 0·47 to 0·56 while that of the second set ranged between 0·07 and 0·51 for different positions.

Five Zn-deficient soils designated A–E (pH 7·3–7·7) and a reference soil F (pH 7·6) were used in a glasshouse study on maize in which five fertilizer treatments: 75 μg P/g alone and together with all combinations of 0 and 5 μg/g of Mg and Zn and with 10 μg Mg + 5 μg Zn/g and a control were applied. The forage yield of soils A–E ranged from 2·5 to 2·9 g when no Zn was applied and from 5·1 to 5·6 g with added Zn, showing that Zn was the major limiting nutrient. Applied Mg significantly increased yield, the main exceptions being soils D and E which had the highest exchangeable Mg.

Addition of Mg to a P but not PZn treatment significantly increased P concentration and uptake. For soils B and E, Zn addition significantly depressed P concentration in maize. The P treatment significantly depressed Zn concentration but increased Mg concentration and uptake by maize. Although Mg application either depressed or had no effect on Mg content of maize, it caused a significant increase in Zn concentration and uptake. The correlation coefficient (r) between Zn and Mg in maize was – 0·61 (P < 0·001). Possibly, Mg was replacing Zn in the clay lattice or in its metallo-protein complex within the root.

Field experiments were conducted to study the differential responses of a wheat crop to water stress during different stages of its growth. Evidence was produced to show that both the flowering phase and the stage of grain filling and maturation were more sensitive to drought than the vegetative period of growth. Yield of wheat was not reduced when the crop suffered from cycles of water stress induced during the vegetative period, if the crop received favourable water regimes thereafter. Efficiency of water utilization from different water treatments was assessed. There was no relation between the protein and starch contents of the grain and the type of water treatment.

The effects of different water treatments on crop development and on components of yield were studied.

The phenotypic stability of seven Finnish and Nordic oat cultivars and 12 breeding lines developed at the Hankkija Plant Breeding Institute, Finland, was studied using the Finlay–Wilkinson regression method, Eberhart–Russell stability analysis, principal component analysis (PCA) with biplot presentation, canonical variate analysis (CVA) and Procrustes analysis. Comparison of stability analyses was based on four dissimilar growing seasons. In addition to the measurement of phenotypic stability of grain yield, the performance of 12 morpho-physiological traits was evaluated, including maturity class and structure of canopy and plant stand.

The different stability analyses examined produced uniform results and ranked the cultivars and breeding lines without major disagreements. Lines with exceptionally stable yield performance over the different growing seasons were identified. In general, there was an association of high yielding ability with poor stability. However, some cultivars deviated from this tendency and showed high grain yield production and average stability of yield performance.