In this paper, the first of a series of three in which fat deposition is examined in 42 castrate male Hereford and Friesian cattle, details are given on the experimental material and procedures used in all papers. Whole body composition (anatomical and chemical) and the partitioning of fat within the body are also reported in this paper.

Four, two and 15 animals were slaughtered at 6, 13 and 20 months of age, respectively, after ad libitum feeding of a complete pelleted diet.

The Friesians were heavier than the Herefords, having 10%, 20% and 14% heavier empty bodies at 6, 13 and 20 months, respectively.

At the same age, the Friesians had a greater percentage of empty-body weight as carcass muscle, carcass bone, total body water and total body ash than the Herefords but a lower percentage as dissectible fat and total body lipid. An analysis of linear body measurements showed no difference between breeds in the stage of development of external body dimensions at 20 months of age, and it was concluded that at the same age and stage of development of live weight or size, the Friesians were leaner than the Herefords.

Relative growth coefficients of the fat depots showed late developmental growth in some intra-abdominal depots (omental and perirenal–retroperitoneal) but not in another (mesenteric). Relative growth coefficients of the omental, mesenterie and intermuscular depots were different between breeds. The Herefords deposited more dissectible fat subcutaneously than the Friesians whereas the Friesians deposited more in the intraabdominal depots. A multivariate index of fat partitioning, which was not influenced by age or stage of development of the fat depots, was not significantly correlated with fatness, suggesting no direct link between the pattern of fat partitioning and body-fat content.

Breed differences in the distribution of fat within the subcutaneous and intermuscular depots were minor compared with the large difference in the partitioning of fat between depots. It was thus concluded that the factors controlling fat partitioning do not influence the distribution of fat within depots.

The size and number of recognizable fat cells (diameters greater than 5 μm) were examined at several sites in 42 Hereford and Friesian steers. Four, two and 15 animals from each breed were slaughtered at 6, 13 and 20 months of age, respectively, after ad libitum feeding.

For the 15 animals of each breed slaughtered at 20 months, biopsy samples of adipose tissue were removed at 10, 13 and 17 months from the 12th rib, midloin, rump and perirenal sites. Samples from these sites and from the brisket (subcutaneous), prescapular (intermuscular) and omental sites were also removed from the carcasses of slaughtered animals. Fat cell diameter (microscopic technique) and dry matter (from which lipid content was predicted) were measured on all samples. Measurement of fat depth (ultrasound) and surface area at the subcutaneous sites allowed changes in relative number of cells to be estimated during growth.

From biopsied samples it was apparent that the perirenal depot grew almost exclusively through cell enlargement in both breeds. In contrast, the subcutaneous depot grew principally through cell enlargement to about 13 months of age and thereafter through both increase in number of cells and cell enlargement. The trigger for this increase in number of cells was possibly a critical average cell size, although this clearly did not operate in perirenal fat.

Slaughter samples showed that cellularity changes with growth were similar in the perirenal and omental depots (intra-abdominal) whereas changes in the prescapular (intermuscular) site tended to parallel those in the subcutaneous depot.

In relation to fat-free body weight (and therefore taking body size into account) both breeds had similar numbers of intra-abdominal and prescapular fat cells, but the Herefords had approximately double the number of subcutaneous fat cells compared with the Friesians.

Food utilization in relation to growth of body components, and fat mobilization and its hormonal control in vivo, were examined in 15 Hereford and 15 Friesian steers which were slaughtered at 20 months of age. Changes in body composition between 6 and 20 months were calculated from the body composition of these animals and from an additional four and two steers from each breed slaughtered at 6 and 13 months of age, respectively.

The Friesians consumed more food overall (14%) and grew more rapidly (14%), but their intake in relation to metabolic body weight was not different from that of the Herefords. Although the Friesians deposited more protein in relation to lipid there was no breed difference in food conversion ratio, and maintenance requirement relative to empty-body weight0·75 was estimated to be 7% greater in the Friesians than the Herefords. Friesians therefore had a lower efficiency of conversion of food energy to body energy. It is speculated that the higher maintenance requirement of the Friesians was due to a faster rate of protein deposition and a higher proportion of visceral organs with an associated higher rate of protein turnover.

Changes in plasma concentrations of free fatty acids (FFA), insulin, growth hormone (GH), adrenaline and noradrenaline were examined in response to fasting at 12 and 20 months of age. Inaddition plasma concentrations of glucose, thyroxine (T4) and triiodothyronine (T3) were measured at 20 months of age.

At both ages, FFA concentration increased almost linearly with duration of fasting and was not different between breeds. It was therefore unrelated to fat partitioning and a poor index of breed differences in metabolic and body type. Within breeds, the rate at which FFA concentration increased during fasting was correlated with estimated maintenance requirement (r = 0·53). This suggests a different relationship between FFA utilization and maintenance requirement in the two breeds.

During fasting at 12 months of age, Friesians had higher concentrations of plasma GH and noradrenaline. At 20 months of age they had higher concentiations of glucose, insulin and catecholamines. There was no obvious hormonal explanation for the observed differences in body composition or growth efficiency. Correlations between indices of fat partitioning and maintenance requirement were low, suggesting no direct link between the two traits.

The size of the sink on two indeterminate (cv. Hampton and cv. TGM 119) and two determinate (cv. Bossier and cv. TGM 294) cultivars of soya beans were reduced by continuously limiting the number of pods developing at each fruiting node to either one or two, starting from 2 weeks after anthesis, in three field experiments (early 1980, late 1980 and early 1981). Thiswas in order to evaluate the effects of sink size on the development of pod and seed characteristics as well as to quantify the inter-relationships between these characters under humid tropical conditions.

Persistently reducing the number of pods developing at each fruiting node consistently significantly reduced the number of pods per plant, the pod and seed dry weights per plant, the total number of seeds per plant and the harvest index (seed weight as a proportion of total dry weight) in all cultivars when compared with the control. On the other hand, the treated plants of all cultivars generally had longer pods, heavier individual pods and seeds, more seeds per podand greater leaf area and leaf dry weight as well as greater specific leaf weight than the control plants. Compensation indices (percentage increases in size over control) were 25–30% for weight per pod and seed weight per pod; 11–16% for weight per seed and number of seeds per pod and 2–5% for pod length in the treated plants.

Most of the characters measured (except individual weight of pods and seeds, seed weight per pod and number of seeds per pod) had significant interaction effects of sink size, cultivar and season; season had the highest correlation ratio, followed by cultivar, and sink size had the least. Also, nearly all components of seed yield were positively highly significantly correlated with one another; the number of seeds per pod and the number of pods per plant accounted for 76% of the variation in seed dry weight per plant.

It would seem therefore that under the prevailing humid tropical conditions, the most important component of seed yield in soya bean is the number of seeds per pod, as affected by the sink size.

The modelling of the redistribution of soluble salts in soils, in which it is assumed that the amount of water transferred from layer to layer is related to the excess over field capacity of the water content of a layer, is critically examined.

The equation obtained from the dispersion equation by neglecting the diffusive term is solved for the leaching of surface-applied nitrates. It is shown that, by comparing the finite-difference form of this equation to the algebraic formulation of Burns' (1975) model, the two approaches are essentially the same, but that Burns makes approximations that are too inaccurate. In particular, it is incorrect to relate the transfer of water to the excess over the field capacity of the water content of the layer. Burns' model, when applied correctly, requiresmany calculations to be performed, which is costly of computer time. However, it is unnecessary in this problem as the analytic solution is simple and quick to apply.

The incidence of Sclerotinia sclerotiorum (Lib.) de Bary infection in poppies (Papaver somniferum L.) was assessed 9 days before dry maturity in a field experiment which incorporated the effect of nitrogen and phosphorus fertilizer and fungicidal sprays. Infection occurred mainly on the lower stem in the leaf axils.

Nitrogen fertilizer (100 kg N/ha) had no effect on the incidence of Sclerotinia infection but phosphorus fertilizer (100 kg P/ha) increased the incidence from 19% of plants infected to 39%. Fungicides (2 kg benomyl, 50% a.i., plus 2 kg mancozeb, 80% a.i./ha) applied at 10-day intervals from flowering till harvest reduced the incidence of Sclerotinia infection to one third that of non-sprayed treatments.

Sclerotinia infection occurred late in the crop and had little effect on the dry-matter yields of terminal main-stem capsules, lateral branch capsules or stem and leaves but it did influence the distribution of morphine within the plant. The morphine concentration of terminal capsules was lowered by 13% but the concentration of lateral capsules increased by a similar amount giving a total capsule morphine concentration and yield which was similar in both infected and non-infected plants.

The morphine concentration of the stem and leaves of infected plants was 75% greater than that of uninfected plants but the overall morphine concentration of total plant was similar in both infected and non-infected plants. This distribution pattern was interpreted as a result of the restrictive influence of Sclerotinia infection on the vascular system which disrupted the normal translocation of morphine.

Body heat storage changes of cattle were measured by means of simultaneous direct and indirect calorimetry and by thermometry in an environment that alternated in temperature between 12 and 25 °C. When the calorimeter temperature was increased deep body temperature (Tc) increased by approximately 0–5 °C, mean surface temperature (Ts) by 3 °C and mean body temperature (determined from calorimetry, Tb) by 1 °C, but these increases were not fully sustained during the next 24 h. Changes in the three temperatures were related by the equation: δTb = αδTc+(1-α) δTs where a was found to be 0·89±0·027 (S.E.).

Heat stored in the body of cattle subjected to a daily 10 CC range of environmental temperature was measured by calorimetry and thermometry. The daily range of bodycore temperature of the animals was of the order of 0·5 °C but mean skin temperature cycled with a range of approximately 6 °C. Calorimetric estimates of changes in mean body temperature showed good agreement with thermometric estimates when core and mean body temperature changes were weighted in the ratio a: (1 – α) where α was found to be 0·85. This result is consistent with the findings of another study where cattle were subjected to abrupt changes in environmental temperature, the combined best estimate of a from the two studies being 0·86 ± 0·014 (s.E.). The 10 °C range of daily environmental fluctuation resulted in a daily variation of approximately 1 °C in mean body temperature, which is equivalent to the amount of heat produced by the animals every 40 min. It is suggested that a weighting factor α = 0·86 could be employed, using thermometry only, to estimate fluctuations in body heat storage which are likely to occur in animals subjected to fluctuating environmental conditions in the field.

Effects of supplementary irrigation at three periods of grain sorghum development (a) from emergence to a time after floral initiation was completed (b) during heading and flowering and (c) from ending of flowering to maturity, during two seasons, were tested. Grain yield and its components and straw yield were significantly affected by the irrigation treatments, which were themselves considerably affected by rainfall.

The results suggest that water deficits during the three periods, as were specified in this study, had affected grain yield primarily through effects on number of grains during the first period and size of grains in the second period. Effects in the third period were apparently complementary to those of the first and/or the second periods, being either very substantial or negligible, depending on the rain conditions in these periods. Straw yields were mostly affected by irrigation during the third period, mainly as a result of development of late tillers.

High yields of rain-grown sorghum can be obtained if water deficits are avoided by supplementary irrigation during one or more of its growth periods.

The effect of pretreating soya-bean and rapeseed meals with formaldehyde was studied. Soya-bean and rapeseed meals, both untreated and formaldehyde-treated, were fed to cattle receiving a basal diet of silage in a 4 × 4 latin square. Formaldehyde treatment of both meals significantly reduced apparent N digestibility. All four protein supplements increased the amounts of non-ammonia N and amino acid N entering the small intestine over those obtained when silage was fed alone. Formaldehyde treatment of the meals increased the amounts of non-ammonia N and amino acid N entering the small intestine; this effect was significant, however, for only the formaldehyde treatment of the soya-bean meal. The low efficiency of microbial N synthesis observed when silage was fed alone was increased by the inclusion of both of the soyabean meals in the diet but not by the inclusion of the rapeseed meals. Formaldehyde treatment reduced the apparent degradability of the soya-bean meal N, determined in vivo, from 0·90 for the untreated meal to 0·40 for the formaldehyde-treated meal; similarly the degradability of the untreated rapeseed meal was reduced from 0·77 to 0·41 by the formaldehyde treatment. The in sacco technique gave values for degradability for the protein supplements which ranked them in a similar manner as did the in vivo technique; however, for any one meal the in sacco value for degradability was lower than that determined in vivo.

Spring barley straw treated with NaOH, either chopped and ensiled or ground and pelleted, was compared with long untreated straw and hay, in mixed diets of compound and forage fed to yearling dairy heifers. Protein allowance and source were varied by the inclusion of either fishmeal, soya-bean meal or urea in the diet.

Growth rate was improved in two out of three trials by chopped ensiled straw treated with NaOH, compared with long untreated straw, and equalled that supported by hay. Dry-matter intake and digestibility were also improved, although rumen NH3-N concentrations were low. With ground pelleted straw treated with NaOH the effects were less decisive: growth rate was increased once and reduced once compared with long untreated straw, but dry-matter intake was substantially increased. Digestibility remained similar to that of long untreated straw, and was unchanged by rate of feeding. NaOH treatment resulted in small changes in molar proportions of VFA. Digestibility of hay fell when concentrates were added to the diet.

Fishmeal increased growth rate with all forms of straw and hay and was more efficient in this respect than either soya-bean meal or urea.

Sequential dry-matter measurements for winter wheat crops grown at different sites during different seasons were plotted against accumulated potential evaporation. A relation consisting of two intersecting straight lines represented the observations. Early crop growth had a gentle slope due to an incomplete leaf canopy. Later growth occurred at a rate which depended upon the amount of applied nitrogen, the amount of radiation and the availability of water. The intersection occurred consistently at a leaf area index of 1·25.

Five feeding and metabolism trials were conducted on buffaloes fed different amounts of groundnut oil as a source of supplemental fat. Ca and P retentions were determined. The first two trials were conducted on 12 and 16 milch buffaloes and the other three trials on 15, 15 and 4 buffalo bulls. The dietary fat ranged from 1·32 to 6·00% of the ration in milch buffaloes and 0·51 to 6·33% in buffalo bulls. The retentions of Ca and P did not differ significantly with the percentage of fat in the ration. This showed that the phenomenon of formation of Ca soaps with fatty acids in non-ruminants with consequent wastage of Ca does not seem to be applicable to ruminants which have a much lower pH in the duodenum and upper jejunum. It is concluded that under practical conditions of feeding, within the usual range of dietary fat in ruminants, there is no likelihood of an adverse effect on Ca and P nutrition such as is encountered in non-ruminants on high-fat diets.

A multifactorial experiment sown to winter wheat cv. Hustler in autumn 1978 tested the effects of combinations of the following eight factors, each at two levels: drill type, sowing date, amount of nitrogen, division of nitrogen, irrigation, autumn pesticide (aldicarb), summer aphicide (pirimicarb), and fungicide (carbendazim, maneb and tridemorph).

The mean grain yield of all plots was 9·7 t/ha and the best eight-plot treatment mean was 11·3 t/ha. The factors that had the greatest effect on yield were aphicide and fungicide, mainly from the control of Metopolophium dirhodum and Septoria spp. respectively. Both factors increased grain size and their effects were more than additive and greater with 250 than with 160 kg N/ha. Aphicide and fungicide also temporarily decreased the numbers of microbes on the developing ears. Autumn pesticide gave good control of aphids in the winter and some control in the summer: it also decreased nematode populations and slightly increased yields.

Precision sowing compared with random distribution of seeds along the row had little effect on growth or yield. Sowing on 21 September compared with 13 October greatly increased growth early in the season but had less effect after anthesis; it was the only factor that increased yield when aphicide and fungicide were applied. There was negligible infection by barley yellow dwarf virus in crops sown on either date. The amount and division of N fertilizer affected N uptake early in the season and had small effects on the production and survival of tillers. Three N applications instead of one slightly increased grain yields but did not affect total N uptake by grains plus straw, which averaged 190 kg N/ha. The larger amount of N always increased N uptake but decreased yield in the absence of aphicide and fungicide. Irrigation slightly decreased yield despite prolonging the duration of green leaf area.

Grain growth and final weight per grain were measured in 12 genotypes of spring barley, the parents and progeny of two six-row × two-row crosses. Weight of carpels or grains from node 10 on the main shoot ear was measured from shortly after meiosis until grains were at maximum dry weight. Similar measurements were made at representative node positions along the ear of Proctor and of Midas spring barley cultivars.

From about 10 days after anthesis grains grew at a constant rate for about 3 weeks. Amongst genotypes growth rate of the median grain ranged from 1·4 to 2'2 mg/day and there was a very highly significant positive correlation between growth rate and final grain weight. A similar relationship was found among grain positions on the ear. For about 10 days after anthesis growth was exponential and although relative growth rate did not differ between genotypes or grain positions there was a highly significant difference between caryopsis weights during this phase. There were significant correlations between final grain weight and carpel weight at anthesis and between final grain weight and husk weight at anthesis. In the period between meiosis and anthesis growth was exponential and the relative growth rate did not differ between genotypes or node positions on the ear. There were significant differences between carpel weights during this phase. Carpel weight at anthesis and carpel linear dimensions at meiosis were correlated.

These data suggest that the initial size of carpel is an important factor in determining growth rate and potential grain weight. Potential grain size in barley may be determined by physical limitations imposed by the lemma and palea or may be causally related to the size of the carpel. The relative size of the carpel is determined by the time of meiosis and potential size may also be affected by pre-anthesis conditions.

The digestibility and rumen metabolism of diets containing as 50% of their organic matter (OM), cotton straw (CS) untreated, treated with sodium hydroxide and treated with ozone, were studied in sheep cannulated in the rumen and at the duodenum with simple cannulae. The concentration of total volatile fatty acids (VFA) in the rumen of sheep given the ozone and NaOH treatments was higher than in the untreated diet; however, the VFA profiles were not different. The rumen dehydrogenase activity, suggested to reflect general microbial activity, was higher by 83 and 81% in the ozone and NaOH treatments respectively, than in the untreated.

Apparent digestibility of organic matter in the ozone-treated diet was 74·6%; 1·25 and 1·17 times higher than in the untreated and NaOH-treated diets respectively. The calculated values for organic matter and cell-wall digestibilities of the cotton straw in the complete diets were: 30·0, 20·0; 60·8, 60·0; and 39·6, 39·7%, respectively, for the untreated, ozone and NaOH-treated cotton straw. Nitrogen metabolism was not impaired by the presence of formic acid in the ozonated cotton straw; the apparent absorption of N from the intestine and the apparent digestibility of N were higher in the ozonetreated diet than in the untreated or NaOH-treated diet.

The proportion of organic matter and cell walls digested in the rumen was higher in the NaOH and ozone treatments than in the untreated, and the possible reasons for that are discussed. A positive relationship was found between cell-wall digestion in the rumen (% of intake) and the rate of passage (% per h) of particulate matter from the rumen. The interpretation of this relationship is discussed in general and in view of the results of the present study.

The digestibility of cell wall (CW) monosaccharides of diets containing as 50 % of their OM, untreated, sodium hydroxide and ozone-treated cotton straw (CS), was studied in sheep cannulated in the rumen and at the duodenum with simple cannulae.

CS contributed the major part of the dietary cell-wall glucose, xylose and uronic acid in the three diets. The digestibility of the diets' CW glucose was 38·2, 66·6 and 50·2 % for the untreated, ozone and NaOH-treated CS-diets, respectively. Ozone and NaOH treatments significantly increased the digestibility of cotton straw CW glucose by 108 and 42%, respectively. The highest digestibility of CW xylose in the whole diet was obtained in the NaOH treatment: 43·4% as compared with 19·1 and 31·2% in the untreated and ozone-treated diets. The calculated values of CW xylose digestibility in CS were lower than those of CW glucose. Ozone remarkably increased the degradation of CW uronic acids. The calculated value for ozonated CS was 68·7%, 4·09 and 1·47 times higher than in the untreated and NaOH-treated CS.

Irrespective of diet, the digestibilities of the minor CW sugars, i.e. arabinose, galactose and mannose, were high, and their degradation was largely completed in the rumen. The contribution of the hindgut flora was expressed mainly in degrading the residues of the potentially digestible CW glucose and CW xylose.

The digestibility values of ADF-cellulose and those of CW glucose were compatible, whereas those of hemicellulose (determined as NDF-ADF) and CW non-glucose polysaccharides (NGP) were clearly different. The digestibility of NGP was 16·8, 36·6 and 43·2% for the untreated, ozone and NaOH-treated CS, respectively. It is suggested that those values more closely represent the digestibility of the ‘true hemicellulose’ fraction.

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

Drinking regimes of Bedouin goats affect their feeding behaviour and the ruminal environmental conditions, as expressed by changes in osmotic pressure as well as in pH of the rumen content. The osmotic concentration of the rumen content of a goat drinking once daily was 330 m-osmole/kg just before drinking. After water deprivation for 4 days, the osmotic concentration reached 360 m-osmole/kg and, immediately after excessive drinking, decreased to 82 m-osmole/kg. After a short while, the osmotic concentration increased to 300 m-osmole/kg and after 13 h reached the peak of 440 mosmole/kg, mainly owing to the release of degradation products. The pH was also affected by food consumption. Just prior to drinking, the pH in the rumen of dehydrated goats was 6·9. It decreased to 6·0 after excessive drinking and feeding. Later, it ranged between 6·4 and 7·1.

Most of the micro-organisms in the rumen are attached to the fibres fraction. No difference could be observed in direct bacterial counts in the fluid fraction between dehydrated and goats drinking daily. However, the number of protozoa was reduced in dehydrated goats, especially after excessive drinking, as some species of protozoa seem to explode in a hypo-osmotic ambient.

The fermentation capacity of the fibres fraction was higher than that of the fluid fraction, indicating also the presence of more micro-organisms in the fibres. In addition, the osmotic changes occurring during the dehydration-rehydration cycles had no significant effect on fermentation capability of the rumen micro-organisms.

At a low osmotic concentration in an NaCl deficient ambient, there was some decrease in fermentation rate, but this could be nullified with the addition of NaCl, which is required for microbial activity. The decrease in fermentation rate is not due to its effect on the osmotic concentration. The micro-organisms in the fibres fraction were found to be less affected by NaCl deficiency in the ambient medium.

The variation in setting fruit and immature fruit abscission at successive nodes of an individual panicle, and in panicles at different directions of the canopy in an individual tree, were studied in cashew (Anacardium occidentale L.). The numbers of perfect flowers and fruits set increased from the proximal to the distal end with the maximum yield at the fifth or sixth nodes in a panicle of 8–10 branches. The productivity of an entire inflorescence or a whole fruiting branch was related to its orientation with respect to the sun. The numbers of nodes and fruits set and the percentage of fruit retained were maximal in panicles located on the western and southern sides of the canopy. Tea mosquito damage was also less on these sides of the canopy but the physiological disorder of ‘apple’ cracking was higher here than on the eastern and northern sides. These variations are discussed in relation to the differences in the incident photosynthetically active radiation on these sides.