Seven Angus steers were reared under controlled conditions, slaughtered and their carcasses dissected. Muscles, fat, bones, connective tissues and samples of the steers' diet were measured by gamma spectrometry and the concentrations of potassium and caesium-137 determined. Significant variations in the concentration of each element were found both within and between tissues. Average potassium concentration was about four times greater in the muscle tissue than in the remainder of the carcass. Caesium/potassium ratios were similar in both Caesium/potassium ratios were similar in both bone.

The main conclusions reached were as follows:

(1) The variations of potassium concentrations in muscle may impose limitations on the potassium-40 technique for estimating muscle content of the living animal for scientific purposes, though not necessarily for estimating commercial value.

(2) Differences between animals in caesium-137 content of muscle were fairly consistent over the different muscle groups, and bore some relationship to caesium intake. This indicates that it may be possible to utilize caesium content of a representative muscle to monitor caesium-137 fallout in remote regions of Australia, where milk is not produced.

A quantitative description of the factors underlying seasonal changes in herbage digestibility is developed and applied to sets of data from S. 24 and S. 23 perennial ryegrass. A new variable, relative maturity, is used to describe the effect of defoliation in interrupting the process of tiller maturation which leads to the decline in digestibility. For S. 24, the model explained 95·5% of variation in digestibility decline, R.S.D. = 1·07, allowing accurate prediction of digestibility. For S. 23, 87·5% of variation was explained, R.S.D. = 1·85. The model for S. 24 also worked well on data from a different site, nitrogen level and cutting regime, and the question of the model's generality is discussed. Relative maturity appears to be a useful concept in describing the physiological maturity of swards under different harvesting regimes.

1. Yields of plots estimated from the known weights of “perfect” beet (i.e. plants with no gaps in the ring immediately surrounding them) showed 18 × 9 in. to be the optimum spacing.

2. Sugar analyses performed on individual “perfect” beet showed that very diminutive roots were low in sugar, but that in general sugar percentage decreased with increasing weight of root; the decrease was, however, slight and only amounted to unity for an increase of 1000 g. in weight of root.

3. In a dry year the roots immediately surrounding a gap compensated to the extent of 80–89% for the missing plant: the allocation to the individual neighbours was approximately inversely proportional to the square of their distance from the site of the gap. In a wet year compensation was less complete, amounting to from 41 to 84% under various spacing treatments. In both years compensation was less complete in the case of tops than in the case of roots.

4. Within classes of beet similar in regard to spacing treatment and gappiness there still remained considerable variation due to soil and to genetic heterogeneity.

5. The genetic variability of commercial seed appears to be large, so that in sugar beet experiments it is very desirable that each plot should carry a considerable number of plants: in these experiments, assuming that all variations within ultimate classes were of genetic origin, 400 plants would have been necessary to reduce the plot error due to genetic variability to 2% of the mean.

The respective effect of the period of lactation and the age of the cow on the yield and quality of the milk have previously been studied separately (see J. Agric. Sci. 17, PtI, p. 118, “The Influence of the Stage of Lactation and the Breed of the Cow on the Yield and Quality of the Milk,” and 17, Pt III, p. 420, “The Influence of the Age of the Cow on the Yield and Quality of the Milk”), and an analysis of the data has now been made with regard to the joint influence of these factors.

The average yields of irrigated long-staple cotton in the three-course rotations: dura, fallow, cotton, D-F-C; lubia, fallow, cotton, L-F-C; and fallow, fallow, cotton, F-F-C, were studied over 12 years in an experiment in the Sudan Gezira; the fallows (resting land) were either hoed or were left uncultivated during the rainy season, so that the effects of the operation of hoeing on the subsequent cotton yields could be measured.

Where the fallows were unhoed L-F-C yielded more cotton than F-F-C, which gave at first higher yields than D-F-C, although this difference had disappeared by the end of the period. Fallow hoeing increased yields in all rotations; this response was maintained in D-F-C and L-F-C. In F-F-C the response to hoeing either fallow diminished steadily in time and whilst the higher response to hoeing both fallows also decreased, its rate of decrease was no greater than when only one fallow was hoed. The response to hoeing fluctuated considerably from year to year. In all rotations these fluctuations were associated with rainfall and the relationships have been expressed in the form of regression equations; separate equations were necessary for each rotation as the relationships were quite distinct.

The variety X1730 A out-yielded Domains Sakel. There were interactions between the varieties and the other treatments, but these interactions were such that the varieties differed more at higher levels of yield and did not modify the above conclusions appreciably.

A disease, which is due to a hitherto unrecorded attack of eelworm, has been found causing a considerable amount of damage to black currant plantations in the vicinity of Cambridge.

Four restriction enzymes (AluI, HhaI, MspI and RsaI), either individually or in combination, were used in terminal restriction fragment length polymorphism (T-RFLP) analysis to: (i) characterize the chicken intestinal bacterial community; and (ii) tentatively identify intestinal bacterial groups related with increased performance parameters in broiler chickens. Balanced commercial diets free of any feed antibiotics were offered to broilers assigned randomly to one of the five dietary treatments: control (C) (commercial diet with no additive), inulin (I), fructose caramel, propyl propane thiosulphonate (PTS-O)-45 and PTS-O-90. Except for the inulin-supplemented diet, multivariate statistical analysis of T-RFLP profiles based on individual enzymes or their combinations showed that the caecal bacterial community composition was significantly different among diets, particularly between the control and the supplemented diets. Individual RsaI and the combination AluI + RsaI proved to be the most useful to discriminate between dietary treatments. Clostridiaceae 1, Lachnospiraceae, Ruminococcaceae and Micrococcaceae were tentatively identified as those families most likely to be implicated in defining the caecal microbiota composition of growing broiler chickens, and also as those most closely related with differences in productive parameters.

Managed grasslands are characterized by rotations of leys and arable crops. The regime of water flow evolves during the leys because of earthworm and root activity, climate and agricultural practices (fertilizer, cutting and cattle trampling). The effects of duration of the leys, cattle trampling and fertilizer practice on the movement of water through sandy loam soil profiles were investigated in managed grassland of a dairy operation. Experiments using tracer chemicals were performed, with or without cattle slurry application, with cutting or grazing, in the 1st and the 3rd year of ley, and in winter rye. Each plot was irrigated for an hour with 18·5 mm of water containing a conservative tracer, potassium bromide; 24 h after irrigation, macropores >1 mm were recorded visually on a horizontal plan of 0·7 m2 at five depths (10, 30, 40, 70 and 100 cm). The bromide (Br−) concentration in soil was also analysed at these depths and the density of the different earthworm species were recorded. The density of macropores was not directly influenced by the factors investigated. The abundance of anecic earthworms was larger after 3 years of ley and was not affected by grazing (trampling or dung pat deposits) or fertilizer practice. The water infiltration estimated from the Br− concentration was not influenced by fertilizer practice and was reduced after 3 years of ley due to settlement, but was greater than that for the arable phase of the rotation. As shown by Br− concentration, preferential flow was induced by the grazing regime. Infiltrating water may bypass the soil matrix under similar or more extreme conditions than in the current experiment. Such hydraulic functioning in the grazing regime is expected to reduce the risk of leaching of nitrate contained in soil water.

1. On twelve occasions covering a complete seasonal cycle rumen mierobial end-product concentrations were measured in a group of sheep allowed to graze a pasture for 1 hr. Considerable differences were obtained in the rises in total volatile fatty acid and ammonia after feeding, in average rumen protein nitrogen and in free mierobial count.

2. Seven samples of fresh herbage wfere fed to groups of sheep in pens at different levels of intake. Increase in feed intake with five of the herbages produced significant increases in rumen ammonia and total volatile fatty acid and with one herbage there was a significant increase in protein nitrogen. Free mierobial count was measured after feeding three herbages and was found to be independent of intake level.

The majority of Awassi flocks in Israel and throughout the Middle East are kept under primitive extensive conditions. Their main product is the lamb, and milk as a by-product is gained occasionally after weaning. A few estimates of the milk yields of these sheep may be found in the literature (Hirsh, 1931; Finci, 1957; Becker, 1958), however, none are based on actual measurements.

The pattern, production and survival of tillers was studied in two spring wheat varieties in field and pot experiments for two seasons.

The time-trend of tillering was such that tiller production reached a peak well before ear emergence, then death reduced the number of vegetative shoots to a level determined by seed rate (in the field) and nitrogen level (in field and pot experiments), and thereafter the number of live shoots remained more or less constant. In field experiments plants grown at high seed rates and low rates of N application attained their maximum numbers of shoots at an earlier date. Number of shoots perm2 increased with an increase in seed rate and N level. However, the number of fertile shoots per plant at harvest decreased with an increase in seed rate and were composed mostly of main shoots. The high mortality rate of shoots was attributed to the high temperatures prevailing in this country during the growth period. Mortality of shoots started earlier at high seed rates and low rates of N application.

In pot experiments, giving the N fertilizer in doses throughout the growth period reduced the rate of mortality of tillers rather than increasing their rate of initiation. A lower dose of N, given in portions over a long period, resulted in a higher number of live tillers than a dose double this amount given once at sowing. Numbers of spikelets and grains increased to a greater extent as a result of split application of N than did grain weight per ear of main shoots and of primary + secondary tillers. Mexipak had fewer spikelets per ear than Giza 155 and yet its number of grains was greater, particularly in ears of primary and secondary tillers.

1. Five pairs of Suffolk twin lambs were used and one of each pair was injected twice daily with 2 mg. of a growth hormone preparation for 2 weeks.

2. Treatment was begun when they were between 3 and 4 weeks old, the total number of follicles in the Suffolk not being complete until 6 weeks old. Skin samples were taken at the beginning and end of the experiment.

3. It was found that in 0·25 sq. cm. of skin the total number of primary follicles was reduced from the beginning to end of the experiment in both control and treated groups, probably because of the expansion of skin area during that time. While the total number of secondary, ‘news’ and ‘plug’ follicles was also reduced in the control group, they were increased in the treated group.

4. Since the secondary to primary follicle ratio was 5·3:1 for the treated group as compared with 4·5:1 for the controls it is concluded that growth hormone increases the number of secondary follicles which develop during the early weeks of postnatal life.

An account has been given of an investigation into the changes which occur during the preservation of the oat and tare crop in the clamp silo.

The material obtained from the clamp was divisible into three types: (1) An uppermost thick layer of mouldy material. (2) “Sweet” silage from the middle layers. (3) Wet “sour” silage from the bottom layer. The spoilt material in the top layer represented approximately 19 per cent. of the whole of the crop contained in the clamp, and in addition to this, the silage was extensively spoilt round the sides of the clamp to an average depth of 12 inches. In comparing the processes of ensilage in the tower and in the clamp, it should be remembered that spoiling of this type only affects the top few inches of the material in the tower silo.

The loss of dry matter in the “sour” silage layer, arising from fermentation and drainage away of juice, amounted to more than one-fifth of the dry matter of the crop originally present in the layer. This represents a much bigger loss than any previously recorded at Cambridge in similar work with tower silos. An exceptionally heavy destruction of carbohydrates further characterised the production of the “sour” silage in the clamp.

The loss of dry matter in the “sweet” silage layer was much smaller and was comparable in magnitude with that occurring during the production of “green fruity” silage in tower silos.

The chemical characteristics of the “sour” silage samples were investigated and were found to conform with results discussed in a previous communication, namely, the samples contained a high proportion of volatile bases to amino acids, and the volatile acids were present in appreciable excess of the non-volatile organic acids.

In two previous communications a summary has been given of the results obtained in determinations of the relative degree of atmospheric pollution, firstly in various parts of the city of Leeds, and secondly in the surrounding semi-urban and rural areas, to a distance in some directions of seven miles from the centre of the city. The results obtained in the latter series indicated clearly the presence of extensive atmospheric pollution, showing the characteristics of coal smoke, in all parts of the area investigated. The degree of pollution was found to fall rapidly on passing in a northerly direction from the centre of the city into an area free from smoke-producing industries, but less rapidly on passing into similar areas to the north-east and east of the city, owing to the greater dispersion of the city smoke in these directions by the prevailing winds. On the opposite side of the city, from north-west round by south to south-east, smoke pollution was found to be very high in all quarters.

Attention is directed in this paper to the desirability, particularly at the present time, of conserving, for purposes of winter-feeding, the pea-pods that accumulate in large quantities at the factories during the pea-canning season. Conservation on the farm is best carried out by the method of ensilage, young pea-pods, such as are obtained in the factory, giving rise to a very satisfactory type of silage without the use of molasses. Broad-bean-pods, on the other hand, do not lend themselves to successful conservation by ensilage, owing to the fact that they become “slimy” in the process and yield an unpalatable product.

Both pea-pods and bean-pods are conserved in the factory by the method of artificial-drying. One such process is described in the present paper. The final product in both cases is obtained as a fine brown meal. Pea-pod meal, in some respects, particularly in regard to its satisfactory content of protein and lime, has a composition not unlike that of the leguminous hays. The similarity, however, does not extend to the fibrous constituent, pea-pod meal having a very much lower fibre content than the hays.

An outstanding characteristic of pea-pod meal is its richness in sugar, no less than 16·5% of the dry matter consisting of a mixture of sucrose and invert sugar. It is the presence of this abundance of sugar that accounts for the favourable fermentation that takes place when young pea-pods in the fresh condition are conserved as silage.

Bean-pod meal displays the same general features in respect of composition, but is distinctly poorer in lime and sugar than the pea-pod meal. Pea-pods and bean-pods, both in the fresh and artificially-dried condition, contain very little carotene and have, therefore, little or no significance as a source of this vitamin A-precursor in the feeding of live-stock.

Digestibility of neutral detergent fibre (NDF) and monosaccharide components of diets containing 60% untreated straw (UTS) or straw treated with sulphur dioxide (TS) and poultrylitter (1:1) plus 40% concentrate at 700 g/day intake was examined in sheep equipped with rumen and duodenal cannulas. An all-concentrate diet (CD) served as a reference ration. The SO2 treatment of straw increased the apparent digestibility of the NDF, glucose, xylose, arabinose and galactose components of the diet from 58·9, 86·7, 55·7, 82·5 and 91·8%, respectively, in the UTS diet to 73·8, 92·6, 77·8, 88·9 and 94·6%, respectively, in the TS diet. Whereas digestion of NDF and glucose in sheep on the TS diet was slightly lower than in those on the CD diet, digestion of xylose, arabinose and galactose was higher. Thus, the digestibility of total monosaccharides in th TS diet was 90·2 % and that of the CD diet only 61% units higher. The SO2 treatment also increased the total rumen volatile fatty acid (VFA) concentration and the proportion of butyric acid in the total VFA compared with the UTS diet.

Rumen ammonia concentration was 7 mg/100 ml lower and nonammonia nitrogen (NAN) flowto the duodenum was 1·3 g/day higher in sheep fed the TS diet compared with the CD diet. The quantity of duodenal N absorbed in the intestine was 10·7 g/day in the TS diet, close to the value of 11·6 g/day found with the CD diet.

The similarity between the TS and CD diets in total monosaccharides digestion and duodenal Nabsorption, confirms the findings of earlier studies that a TS diet is a highly productive ration.

Complementary interaction between the SO2-treated straw and poultry litter components of the TS diet is discussed.

1. On the basis of 5000 records from twelve leading herds of Ayrshire cattle in south-west Scotland for the period 1930–9, a statistical study has been made of some of the causes of variations which occur in butterfat percentage.

2. Butterfat percentage was found to be affected only very slightly by month of calving, age and length of calving intervals.

3. Selection for milk yield would not affect butterfat percentage adversely to any appreciable extent.

4. The average repeatability of butterfat percentage was 0·691 in the present material, and heritability was of the order of 0·50–0·60.

5. Mass selection would be an effective tool in bringing about improvement in butterfat percentage.

As a result of one detailed experiment and four demonstrations carried out on the University Farm at Cambridge the following conclusions can be drawn:

1. Lucerne drilled at a constant seed rate per acre, in narrow rows (3½ and 7 in.), gave a greater yield per acre than when drilled in rows 10½ and 14 in. in width. Over a four-year period the yield of dry matter per acre from narrow rows was half a ton more than from wide rows. No evidence was obtained that weed infestation is reduced by narrow drilling.

2. The broadcasting of 5 lb. of trefoil per acre at the time the lucerne was drilled had no effect on the total yield or on weed infestation.

3. Wild white clover broadcast at the rate of 2 lb. per acre at the time of drilling the lucerne slightly reduced the yield of lucerne in the first harvest year, but subsequently it served to secure some control of weeds, and thereby favoured the persistence of the lucerne. Differences in yield associated with sowing wild white clover were, however, slight.

4. Commercial cocksfoot broadcast at the rate of 10 lb. per acre at the time of drilling the lucerne led to very considerable increases in total yield (nearly 3 tons per acre of dry matter over a four-year period). The increments were obtained principally during the spring growth, and some loss of lucerne plants was suffered, so that in a very dry summer the total aftermath yield was slightly reduced. Since cocksfoot almost completely controlled weeds and its mixture with lucerne was very suitable for hay or for silage, it is regarded as a plant that may be included in a lucerne ley with advantage.

A branching peduncle individual was observed in a population of cow pea Vigna unguiculata (L.) Walp. cv. Ife Brown. Normal plants have unbranched peduncles with flowers arranged in alternate pairs at distal ends of the peduncles. However, the mutant plant has branched peduncles with flowers arranged in pairs alternately along the branches as well as at the ends of the branches. The branches arise in the axils of stipulate trifoliate leaves which develop on the peduncles. The normal plant has between one and four pods per peduncle, whereas the mutant is capable of carrying between two and ten pods per peduncle. The branching trait is under genetic control, involving a single gene with the normal peduncle completely dominant over the mutant. Evidence for the genetic control and its possible usage is discussed. Data on some agronomic properties of the mutant are also presented.

Higher pH values had been established under grass than under clover pastures during a prior pasture phase. The differential effect of pasture species on the pH of the subsequently cultivated soil was reduced in time, but continued to be significant after 4 years.

There was greater cation exchange capacity and lower percentage base saturation after clovers than after grasses. The cation exchange capacity of the inorganic fraction of the soil was not affected by the type of pasture and did not change with time. The difference in cation exchange capacity for the cultivated soil was, therefore, due to the difference in the cation exchange capacity of organic matter residual from the clover and grass pastures.