bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of sustained lactation on intake of solid food and growth rate of lambs
Authors: Doney J. M. , Peart J. N.
Published: March 2009

An experiment was designed to investigate the effect of a sustained lactation pattern on the intake of milk or solid food by lambs and on their consequent growth rate. Normal lactation pattern was compared with sustained lactation, achieved by fostering lambs at 24 days of age on to newly-lambed nurse ewes. Two genotypes of lamb were used; these were pure-bred Scottish Blackface and Textel × Blackface. Lambs were offered one of two qualities of pelleted concentrate food from 4 weeks of age.

Maximum daily intakes of milk were 2·16 and 1·87 kg/day, respectively, for fostered and non-fostered lambs. This differential was maintained until the 10th week. Pattern of lactation had no significant effect on total energy intake from milk and solid food combined or on live-weight gain up to 10 weeks of age. Texel cross lambs consumed more food than did pure Blackface lambs and showed correspondingly higher rates of live-weight gain. Lambs ate slightly more of the higher quality pellets than the lower but there was no effect of solid food quality on milk intake. Within breed of lamb there was a negative relationship between intake of milk and of solid food.
Delaying ripening in harvested Nigerian green plantains
Authors: Ndubizu T. O. C.
Published: March 2009

Mature green plantains (Bini variety) dipped in fungicide and stored with Purafil in polyethylene bags, remained green and hard for 3–4 weeks before ripening started. Fruits stored with Purafil or potassium permanganate kept longer (by 2 weeks) than those stored with potassium iodate or potassium dichromate. Severe chemical and fungal damage occurred in fruits stored with calcium hypochlorite, indicating that plantain fruits may be sensitive to chlorine. No significant difference in storage life was observed between fruits stored in polyethylene bags alone and those stored in potassium iodate or potassium dichromate. There was much lower incidence of fungal infection in fruits dipped in thiabendazole (1 g/l) than those dipped in Diathane M45 (3 g/1). Fruits dipped in thiabendazole before storage remained virtually free of fungal attack even after they had completely ripened.
The effect of disposing high rates of copper-rich pig slurry on grassland on the health of grazing sheep
Authors: Gracey H. I. , Stewart T. A. , Woodside J. D. , Thompson R. H.
Published: March 2009

Over a 3-year period 900 m3/ha of copper-rich pig slurry were spread during the growing season on a 0·6 ha permanent grassland sward and the grass continually grazed off each season with the same sheep. A total of 47 kg Cu/ha were applied to the area and this increased the EDTA-extractable copper in the topsoil. Herbage copper concentrations clearly showed that sheep grazing the area were continually exposed to high concentrations, and that most of the copper was present as surface contamination. Large quantities of copper were excreted in the sheep faeces indicating that copper passed through the animal.

Monthly blood samples from the sheep showed that the enzyme glutamic-oxaloacetic transaminase (GOT) concentrations were slightly higher than those in sheep grazing an area which received no copper over the same period. By the end of the second season (October 1971) over 2000 i.u. GOT/1 were recorded in some sheep grazing the slurry treated area indicating severe liver breakdown at that time. However, during the winter when the sheep were inwintered, serum GOT concentrations decreased considerably. In the final grazing season a 0·2 ha area received monthly applications of copper sulphate instead of slurry. All sheep were slaughtered in November 1972 for post-mortem examination. There was little difference in the copper concentrations in the liver and kidneys of the sheep grazing the control and the slurry areas, although the sheep which grazed the copper sulphate area in the final season had higher concentrations.

As no sheep died from chronic copper poisoning during the course of the investigation there would appear to be little or no danger to the health of sheep from grazing land which is receiving pig slurry at rates which supply less than 16 kg Cu/ha/year.
Sodium and Potassium Fertilizer in Relation to Soil Physical Properties and sugar-beet yield
Authors: Draycott A. P. , Durrant M. J. , Davies D. B. , Vaidyanathan L. V.
Published: March 2009

Despite much experimental evidence showing that sodium fertilizer increases sugar–beet yield and decreases need for potassium, there is resistance to its use on some soil types through fears of deterioration in soil structure. Twelve field experiments with sugar beet were made in Eastern England, testing all combinations of autumn and spring applications of 0, 150 and 300 kg Na/ha and 0, 83 and 333 kg K/ha. Fields were chosen with soils of loamy very fine sand, very fine sandy loam, sandy clay loam and clay loam textures. Micro–plot and controlled environment studies were also made with the same soils to examine effects of sodium on seedling emergence and growth.

Visual assessments of soil physical state following sodium application revealed no effect in the year sugar beet was grown nor in the following spring when cereals were grown. Measurements of physical properties of soils treated with sodium suggested that applications of several times the recommended amounts of sodium fertilizer would not damage soil structure. However, sodium fertilizer increased the osmotic suction of soil solution which, under some circumstances, e.g. dry springs or giving the fertilizer close to the time of sowing, decreased germination and seedling growth. For this reason and not because it has a detrimental effect on soil physical condition, sodium fertilizer best given in the autumn or some weeks before sowing.
Fat deposition in Hereford and Friesian steers: 1. Body composition and partitioning of fat between depots
Authors: Truscott T. G. , Wood J. D. , MacFie H. J. H.
Published: March 2009

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, afterad libitumfeeding 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.
Fat deposition in Hereford and Friesian steers: 2. Cellular development of the major fat depots
Authors: Truscott T. G. , Wood J. D. , Denny H. R.
Published: March 2009

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, afterad libitumfeeding.

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.
Body heat storage in steers (Bos taurus) in fluctuating thermal environments
Authors: McLean J. A. , Stombaugh D. P. , Downie A. J. , Glasbey C. A.
Published: March 2009

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.
Effect of dietary fat on the retention of calcium and phosphorus in buffaloes (Bos bubalis)
Authors: Nath K. , Agarwala O. N.
Published: March 2009

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.
The long-term accumulation and depletion of copper in the liver of different breeds of sheep fed diets of differing copper content
Authors: Woolliams J. A. , Suttle N. F. , Wiener G. , Field A. C. , Woolliams C.
Published: March 2009

Changes in Cu concentration in the livers of adult Scottish Blackface (B), Welsh Mountain (W) and B × W ewes fed diets containing 4, 9, 17 and 29 mg Cu/kg D.M. were measured over a 28-week period. Measurement continued during two further periods of 18 weeks when first all sheep were fed the diet containing 4 mg Cu/kg D.M. and finally, when 4 mg Mo/kg D.M. was added to this diet.

During the first period the increase on all diets was least in B ewes and, apart from the 4 mg Cu/kg D.M. diet, greatest in W ewes; this difference increased as the Cu in the diet increased. The rate of increase for all ewes diminished towards the end of the period. All breed types retained proportionately less Cu in their livers as the Cu in the diet increased; at one extreme B ewes fed 17 or 29 mg Cu/kg D.M. retained equal amounts.

When during the second period all sheep were fed the 4 mg Cu/kg D.M. diet the Cu concentration in their livers decreased, the rate of decrease being greatest for ewes whose mean concentration in the liver was highest, but at similar concentrations the decrease was greater in B than W ewes. During the final period the decrease was faster and was again associated with the mean Cu concentration, but the decrease was not significantly affected by breed.

Throughout the trial, W ewes had the highest concentration of Cu in their plasma, whilst B ewes and ewes fed the 4 mg Cu/kg D.M. diet throughout had the lowest concentrations both in plasma and in their kidneys at slaughter.

The results show that breeds differ in their ability to retain Cu from the diet in their livers. The magnitude of these differences depends on the intake of Cu and Mo from the diet and is affected by the concentration of Cu in the liver. Breed differences in the absorption and endogenous loss of Cu are suggested.
The comparative effects of defoliation, treading and excreta on a Lolium perenne-Trifolium repens pasture grazed by sheep
Authors: Curll M. L. , Wilkins R. J.
Published: March 2009

The effects of treading and the return of excreta on a Lolium perenne-Trifolium repens sward defoliated by sheep set-stccked at high and low stocking rates were examined. Sward performance was measured inside ‘graze-through’ cages which allowed defoliation without treading and excreta return, and outside where sheep grazed either fitted with harness to prevent the return of excreta or unharnessed to allow the normal return of excreta. Live-weight gain was measured from excreta return and non-return swards. The treatments imposed had large effects on herbage growth and botanical composition.

At a stocking rate of 25 yearling wethers/ha, sheep excreted about 1·1 kg N/ha/day, which increased soil N and led to an increase in herbage growth of about 26 %. The return of excreta increased ryegrass tiller density and this was partly responsible for a 26% reduction in the proportion of clover in the sward; the weight of clover was 13% loss where excreta were returned, and on this treatment stolon length at the end of the experiment was similar to that at the beginning. Doubling the stocking rate increased the N returned via excreta to about 1·3 kg N/ha/day, and this increased herbage growth by 53% but suppressed the proportion of clover by 21%, though not the weight of clover. Clover stolon length decreased during the experiment at this stocking rate, both with and without the return of excreta. Sheep live-weight change benefited from the stimulus to herbage growth where excreta were returned at the high stocking rate, but not at the low stocking rate.

Treading by 25 sheep/ha increased soil compaction but had no significant (P > 0·05) overall effect on herbage growth and botanical composition. However, treading by double the number of grazing animals significantly reduced herbage growth by 10%, plant root weight by 47% and the proportion of clover in the sward by 11%.

Differences in sward performance between stocking rates were due more to the difference in defoliation intensity between these stocking rates than to either treading or the return of excreta.
Fatty acid composition of depot fats from gnotobiotic lambs
Authors: Leat W. M. F. , Kemp P. , Lysons R. J. , Alexander T. J. L.
Published: March 2009

The fatty acid composition of the depot fats of lambs reared for 4–5 months under gnotobiotio conditions have been determined and an estimate made of the endogenous synthesis of stearic acid.

In an uninoculated gnotobiotic lamb no hydrogenation of dietary lipids occurred in the rumen and this was reflected in the virtual absence oftransacids in depot lipids. In this animal the stearic acid content of perirenal depot fat accounted for 16% of the total fatty acids which was similar to the value found in newborn lambs (17%). Inoculation of the rumen of two gnotobiotic lambs with seven species of bacteria resulted in the establishment of partial hydrogenation processes in the rumen. Varioustransisomers of octadecenoic acids were produced in these lambs from the dietary fatty acids but no stearic acid was formed.

These findings are compared with the fatty acid composition of depot fats of other herbivorous and omnivorous animals.
Breeding for resistance to root-knot nematodes in tomatoes
Authors: Fatunla T. , Salu A.
Published: March 2009

Resistance in Rossol and Nematex is separately conditioned by single genes. The genes are incompletely dominant and non-allelic. It was not possible to distinguish between homozygous and heterozygous resistant plants in segregating families.
Thein vitrodigested cell wall and fermentation characteristics of grasses as affected by temperature and humidity during their growth
Authors: Moir K. W. , Wilson J. R. , Blight G. W.
Published: March 2009

Total cell wall,in vitrodigested cell wall and fermentation-gas production were determined in the separated tops and stubble of five tropical and two temperate grass species grown under controlled temperatures and humidities. As the day/night temperatures increased from 18/10 to 25/17 °C the total cell wall andin vitrodigested cell wall increased. With a further increase to 32/24 °C the total cell wall increased, but not thein vitrodigested cell wall.In vitrodigested cell-wall values were also calculated from a previously derived relationship betweenin vitrodigested cell wall and total cell wall. The differences between observed and calculated values increased (negatively) with increasing growth temperature suggesting that thein vitrodigested cell wall was depressed with increasing growth temperatures, but the extent of this depression was small.

In vitrogas production from the fermentation of plant tops or stubble in buffered rumen fluid for 24 h was significantly affected by growth temperature and humidity, apparently because of changes in chemical composition induced by the treatments. The volume of gas produced between 24 and 48 h fermentation times was appreciably lower from stubble than from plant tops and this was thought to be due to a higher resistance of part of the cell wall of stubble to digestion by rumen bacteria. Gas production in this period was slightly lower in the tops of grasses grown at the lower temperatures, but this could have been an indirect effect from an associated decrease in the total cell wall.
Studies on the nutritive value of some common Egyptian feedingstuffs. I. Nitrogen retention and ruminal ammonia curves
Authors: El-Shazly K.
Published: March 2009

1. Ten successive trials with two Rahmany adult ewes were carried out with the aim of comparing the nutritive values of the nitrogenous constituents of some concentrates used in Egypt as supplements in summer rations (decorticated cottonseed cake, linseed-oil meal and beans (Vicia faba)) and of animal proteins (meat meal, fish meal and casein) and of barseem (Trifolium alexandrinum). Wheat straw was employed as the main roughage in the ration. Nitrogen intake for all supplements was 10·16 g./day.

2. Apparent digestion coefficients for crude protein were estimated. Casein had the highest digestibility coefficient while meat meal was the least digestible.

3. Nitrogen retention and ruminal ammonia curves are given for each period. Only three proteins, namely, barseem, cottonseed cake and linseed meal gave positive nitrogen balance at the critical level of nitrogen intake used throughout the trials. Fish meal improved nitrogen retention significantly. Meat meal and beans did not improve nitrogen retention. The addition of 70 g. starch to beans improved nitrogen retention significantly.
A large-scale test of the effects of food restriction on the performance of fattening pigs
Authors: Braude R. , Townsend M. Jill , Harrington G. , Rowell J. G.
Published: March 2009

1. A co-ordinated trial has been carried out at twenty-six centres to study the effects of feeding different quantities of food to fattening pigs. The treatments studied were ad lib. feeding throughout, ad lib. feeding to 120 lb. live weight after which the amount of food given was restricted to 6·5 lb./pig/day and two scales of feeding according to live weight, one moderate and one severe (Table 1).

2. Food conversion was best for the pigs on the most restricted feeding scale, being 8% better than that for the pigs fed ad lib.

3. The slower growing pigs were less fat, slightly longer and their depths of eye muscle were greater.

4. The ad lib. fed pigs had higher killing-out percentages and higher weights into cure.

5. The bacon sides from pigs fed on restricted diets yielded a higher proportion of gammon and fore-end and had thicker streaks.

6. Restriction of feeds led to softer fats.

7. An economic appraisal has been made which shows that, on the basis of certain assumptions, the medium feeding scale would have led to a smaller profit per year than the ad lib. or the ad lib. restricted treatments under the price structure and system of grading prevailing during the period of the experiment.
Some water and dry-matter relationships in the food and droppings of laying hens
Authors: Tyler C.
Published: March 2009

1. An experiment with one non-laying and four laying hens was carried out. Food and water consumption was measured hourly from 06.00 to 22.00 hr. and in the same period the exact time of each excretion was noted. Determinations of water and dry matter were made on each separate excretion.

2. Each bird showed a typical pattern of behaviour in relation to the time of day when it ate food and drank water. For any one bird, variations of this pattern from day to day were small.

3. For each bird there was a highly significant relationship between water intake and temperature on the one hand, and water excretion via droppings and eggs on the other. Water intake, however, had a far greater influence than had temperature on water output.

4. Calculations showed that, despite errors caused by not knowing the amount of metabolic water produced, the excretion from the lungs varied greatly from bird to bird on constant intakes of water and also in the same bird at different intakes.
A study of the amount of some invertebrates that are eaten by wild birds in the Egyptian western desert
Authors: Hegazi E. M.
Published: March 2009

A study was conducted at two different sites in the Egyptian western desert to investigate the activity of carnivorous birds on some invertebrates. At the first site (sand-dunes in the Gharbaniat area, 52 km west of Alexandria), the most interesting bird found was the great grey shrike Lanius excubitor which seizes its prey and impales it upon spines of Lycium europaeum or on barbed-wire fencing. Studies carried out from January to July 1977 indicated that this bird prefers to feed on certain tenebrionid or scarabaeid beetles as well as some orthopterous insects and small lizards of the area. At the other site (inland depression near Omaycd, 80 km west of Alexandria, and 12 km from the sea) a snail-eating bird, (bifaciated lark) Alaemon alaudipes, was found to be the commonest bird where the non-saline soil of the site is suitable for the desert snail, Eremina desertorum, to breed, so much so that the snails constitute one of the prominent features of the site.

The latter bird is more active in the winter than in the summer. From February to the end of June 1979, the estimated snail flesh weight eaten by A. alaudipes birds was about 6·50 kg taken from an area of 2·4 ha. The birds seize a snail, fly upwards to a distance of 6–23 m, select a hard stone, then drop the snail. The snail eventually breaks, and the flesh exposed is readily eaten by the bird. In January 1980, a survey was conducted to investigate the species of birds found in the area that extends between Alexandria and el Alamein. Twenty-six resident, as well as migratory, bird species were observed. The number of species and individual birds in cultivated areas, and sites near the sea shore, were found to be greater than those in natural ecosystems at a distance from the sea.
Variability of the blood composition of dairy cows in relation to time of day
Authors: Mansion R. , Rowlands G. J. , Little W. , Collis K. A.
Published: March 2009

A blood sample was taken at each hourly interval between 07.00 and 16.00 h on five consecutive days from each of two groups of five lactating and two groups of five nonlactating cows. The sampling was organized so that each cow was sampled twice daily and once at each time of day. Samples were analysed for blood glucose and haemoglobin, serum urea, inorganic phosphate, Ca, Mg, Na, K, total protein, albumin, Fe and Cu and plasma β-hydroxybutyrate. The sources of variation in the concentration of each constituent were determined.

Definite patterns of changes in concentrations with time of day were observed for β-hydroxybutyrate, urea, Ca, Na, Mg and Cu. In lactating cows there was a 2½-fold increase in the concentration of β-hydroxybutyrate from the lowest at 07.00 to the highest at 11.00 h. Variation in the concentrations of the other constituents with time of day was a relatively small proportion of the total variance.

It was concluded that diurnal variation in blood composition was unlikely to be a major source of error in interpretation for the usual constituents of a metabolic profile test. However, if β-hydroxybutyrate were to be included great care would be required in selecting a time for sampling.
Relationships between the responses of spring wheat genotypes to temperature and photoperiodic treatments and their performance in the field
Authors: Ford Margaret A. , Austin R. B. , Angus W. J. , Sage G. C. M.
Published: March 2009

Thirty-eight spring wheat genotypes of north temperate or low latitude origin, all reasonably well adapted to the English environment, were grown in controlled environments providing the four combinations of 10 and 14 h photoperiods and temperatures of 8 and 16 °C for 6 weeks. They were then transferred to a glasshouse to assess their responses to these treatments. In separate experiments the responses of the genotypes to vernalization for 2 and 4 weeks at 2 and 8 °C were compared with unvernalized controls. The genotypes were also compared in field experiments from early, intermediate or late sowing over 3 years.

Both high temperatures and long days hastened ear emergence. At the higher temperature more leaves and spikelets were produced on the main stem while in long days the plants had fewer leaves and spikelets.

Most genotypes of north temperate and low latitude origin were responsive to photoperiod but not to the vernalization treatments. As a group, the low latitude ones were as responsive as the north temperate group. Five genotypes of north temperate origin were responsive to vernalization but not to photoperiod and were designated as ‘winter’ ones. Pitic 62 and Hork, from low latitudes, were responsive to vernalization and Hork was unique in also being responsive to photoperiod. The main difference between the north temperate and low latitude genotypes was in time to ear emergence and it is suggested that these differences were due to the effects of earliness genes as distinct from those determining photoperiodic response.

Taking all genotypes individually there were no correlations between yield or its sensitivity to sowing date and any of the attributes measured in controlled environments. However, considering class means, the winter genotypes were the latest to reach ear emergence in the field, and their yields, while greatest from the earliest sowings, were proportionally more depressed by late sowing than the others of the north temperate origin. Thus, it may be unwise for plant breeders to incorporate a vernalization response in spring wheat varieties unless genes for ‘earliness’ are also included. The low latitude class gave only slightly lower yields than the north temperate class.

It is concluded that genes other than those controlling responses to photoperiod, temperature and vernalization were more important determinants of the differences in yield among this set of genotypes.
The effect of feed intake on nutrient and hormone levels in jugular and portal blood in goats
Authors: de Jong A.
Published: March 2009

Adult goats provided with permanent jugular and portal vein catheters were used to study the effect of feeding hay and concentrates on blood composition in order to determine which blood constituents might act as signals in the control of feed intake. Animals were fed limited amounts of feed, or were allowed to eat unlimited amounts for restricted periods, once or twice daily. Blood samples were collected at hourly intervals up to 9 h after feeding and often more frequently in the initial hour, and were analysed for volatile fatty acids (VFA), lactate, glucose, insulin and glucagon.

Feed consumption resulted in rapid and large increments of jugular blood acetate, propionate,n-butyrate and 3-methylbutyrate concentrations whereas isobutyrate and 2-methylbutyrate increased only slightly. Jugular propionate,n–butyrate and 3–methyl–butyrate increased within 10 min and acetate within 20 min after feed was offered, both when hay and when concentrates were eaten. Fasting decreased circulating VFA to very low values. As a rule changes of portal VFA paralleled those in the general circulation although both the concentrations and the changes were much greater. Plasma lactate increased within 30 min on a concentrate diet but not at all on a hay diet.

Blood glucose declined in the initial hour after feeding and subsequently increased, resulting in a more or less elevated plateau. In some but not all experiments glucose declined before feed consumption, probably owing to ‘anticipation’. Circulating plasma insulin and glucagon appeared to increase slightly, if at all, after feeding. Increased feed intake was reflected in higher base line glucose and insulin concentrations in the jugular vein but the jugular glucose and insulin response to feed consumption was unaffected. Jugular glucagon was not influenced by the amount of feed. Jugular insulin and glucagon sometimes showed a brief peak during eating. Portal glucose, insulin and glucagon gave essentially the same pattern as seen in the jugular vein.

In conclusion, it appears that, of the substances studied, acetate, propionate, nbutyrate and 3-methylbutyrate are most suited for the function of feedback signals in the physiological control of feed intake in goats under the conditions of the present experiment. It seems less probable that glucose, insulin and glucagon can play such a role.
Estimation and inheritance of stability parameters of grain yield in maize
Authors: Dhillon B. S. , Singh Joginder
Published: March 2009

One hundred and ninety hybrids involving 20 broad-based yellow maize populations were evaluated together with their parents for stability in expression of their grain yield potential by means of linear regression on to an environmental index. Both linear and non-linear components were observed to be significant; the linear component, in general, being the more important. Two high yielding parents, namely variety A 3D and composite Jawahar, had general adaptability, while synthetic A 22 was suited to poor environment and variety SO 4D to good environment. Seventeen hybrids had above average yield and the majority of these exhibited general adaptability.

Combining ability analysis revealed that GCA (general combining ability) was more important than SCA (specific combining ability) in the expression of mean yield. Inheritance of linear regression was controlled predominantly by GCA whereas both GCA and SCA were equally important in the expression of non-linear fluctuations. Variety Cuba was the most desirable parent, as it transmitted to its progeny high grain yield potential and low linear response. The other good combiners for grain yield were variety SC 4D and Prolific composite but these transmitted above average linear response.

Lack of association between grain yield and linear regression of both parents and GCA effects indicated their independent mode of inheritance. It suggested, therefore, that high yield can be combined with general adaptability or responsiveness to either good or poor environment.
Studies of the permanent incisor eruption, and body development, of the Large East African Zebu (Boran): 2. Relations of incisor eruption with body growth, body development, and carcass composition
Authors: Carles A. B. , Lampkin K. Meidie
Published: March 2009

A comparison was made of the growth curves for early and late eruptors (steers whose eruption age of the first incisor pair was less than the mean, and greater than the mean respectively). From birth to 195 weeks early eruptors were consistently heavier than late eruptors (P < 0·01) by approximately 4% of the overall mean body weight. Growth was linear from birth up to 126 weeks of age, and the variability increased markedly from about 60 weeks of age.

The average daily gain from birth to 195 weeks was 341 g. Linear growth-rates for consecutive stages within this period were generally faster for early eruptors, with the differences ranging between 4 and 6% of the mean for periods exceeding 60 weeks. Comparison of these differences showed that linear growth-rates were only significantly different for growth periods of approximately 120 weeks and longer. When the specific growth-rates were compared no differences were significant.

The differences between the growth rates of fast and slow eruptors (steers whose eruption period was less than the mean, and greater than the mean respectively) were not significant, both for linear and specific growth rates.

Early eruptors had larger heads (head length x head width) relative to body weight (P < 0·05), indicating eruption at an earlier stage of body development. Also early eruptors had longer narrower heads, suggesting slower maturation rates.

Partial correlations between eruption age and head length varied from 0·37 to 0·74 (P < 0·01) showing a close relation with stage of head development. Partial correlations with other measures of skeletal development showed that they were of negligible importance relative to head development.

Relations between eruption age of the first incisor pair and six measures of carcass composition were negligible, as none of the partial regression coefficients was significant.
Effects of tillage and direct drilling on soil properties during the growing season in a long-term barley mono-culture system
Authors: Pidgeon J. D. , Soane B. D.
Published: March 2009

Soil responses to deep (30–35 cm) and normal (15–20 cm) mouldboard ploughing, chisel ploughing and zero-tillage have been compared for 7 years in a field experiment growing continuous spring barley near Edinburgh. The soil was of variable texture, from moderately well-drained sandy loam overlying loam to imperfectly to poorly drained sandy clay loam overlying clay loam, classified as stagnogleyic brown earth to cambio stagnogley soil. Soils of this type derived from Carboniferous till are widely used for cereal production in south-east Scotland. Measurements of soil physical properties were made at crop emergence, midseason and at harvest to characterize seasonal and long-term responses to tillage and traffic. After the first 3 years bulk density responses varied little within or between seasons, showing a compacted horizon from 0–15 cm under zero-tillage and a looser horizon from 21–33 cm under deep ploughing compared with normal ploughing. Immediately below the depth of normal ploughing there was no difference in bulk density between this treatment and zero-tillage while in some years the chisel-ploughing treatment was denser. Moisture content responses on a weight basis, together with air-filled porosity responses, showed large differences between treatments particularly at the time of crop emergency, indicating substantial alterations in the soil profile hydrology. Expressed on a volume basis the increased moisture content near the surface under zero-tillage became more pronounced and the other effects disappeared. Cone resistance responses were proportionately larger than those for bulk density and showed one major difference in that below the depth of ploughing cone resistance was greater for zero-tillage than normal ploughing in the sixth and seventh seasons, but not previously. For bulk density, but probably not for cone resistance, there were no increases after the third season of zero-tillage, the soil reaching an equilibrium density for the current management practices and machinery usage.
The apparent digestibility of crude protein by non-ruminants and ruminants
Authors: Glover J. , Duthie D. W.
Published: March 2009

The apparent digestibility of crude protein by the non-ruminants, pigs, horses, rats, man and the rabbit, is shown to be related to the crude protein content of the feed, and the form of the relationship is similar to that for ruminants. With non-ruminants the apparent digestibility of crude protein is markedly depressed by the crude fibre content of the feed, whereas with ruminants the depression is only slight. The relevant equations show that pigs are much more sensitive to crude fibre than horses and rabbits, and both the latter react more markedly to crude fibre than do the ruminants.

Despite the apparently significant differences between the equations for the ruminant and nonruminant herbivores, it is shown that over the normal range of crude protein and crude fibre content in feedingstuffs suitable for herbivores, the apparent digestibility coefficient of crude protein is similar for all. In other words, despite different abilities to cope with crude fibre, the herbivores as a class digest crude protein in normal feeds to much the same extent. On the other hand, the pig, an omnivore, is shown to be very markedly affected by the crude fibre content of such feeds.
Investigations into the use of supplements for the control of hypomagnesaemia in dairy cows during the spring grazing period
Authors: Line C. , Head M. J. , Rook J. A. F. , Foot A. S. , Rowland S. J.
Published: March 2009

1. Three experiments are described on the feeding of supplements of calcined magnesite, linseed cake and vitamin D to dairy cows for the control of hypomagnesaemia and the prevention of hypomagnesaemic tetany on spring pastures.

2. A daily supplement of 2 oz. calcined magnesite either contained in 2 lb. of dredge corn cubes or 4 lb. dredge corn mix, or as a drench, gave adequate protection against the development of hypomagnesaemia in the fifty-six cows to which it was given.

3. The supplements of 3½–4 lb. linseed cake and 12,500 i.u. vitamin D gave only partial protection.

4. The economics of providing dairy herds with magnesite during the early grazing period is discussed.
The effect of hexoestrol implantation on growth, efficiency of food utilization and carcass quality in pigs
Authors: Morgan J. T. , Green F. R. , Costain R. A. , Williams E. F.
Published: March 2009

An experiment is described in which 64 individually-fed pigs were used to investigate the effects of dietary protein status, administration of aureomycin and hexoestrol implantation on growth, efficiency of feed utilization and carcass conformation. The results of hexoestrol implantation and interactions with the other two variables only are reported here. The pigs were implanted at 120 lb. and again at 150 lb. and killed at 200 lb. live-weight.

The main features of hexoestrol treatment were:

1. Body length taken from the anterior edge of the aitch bone to the junction of first rib and sternum was significantly increased by 9·75 mm.

2. The percentage lean in the carcass was increased by 0·82%, representing approximately 1¼ lb. more lean meat in a 155 lb. carcass. The water content of the lean was increased but not significantly.

3. Body fat was reduced but this was not reflected in a significant change in back fat measurements.

4. No changes could be detected in the thyroid or adrenals, but whereas male castrates showed little effect of treatment on other organs apart from a certain amount of urethritis, the intact female manifested major changes in the genital tract. The uterus in particular was greatly enlarged and ovarian activity obviously reduced. The implications of these effects are being examined.

5. There was no response to treatment in terms of growth rate or efficiency of feed utilization.
Nitrogen fixation (C2H2reduction) in the rice rhizosphere soil as influenced by pesticides and methods of their application
Authors: Rao J. L. N. , Pasalu I. C. , Rao V. Rajaramamohan
Published: March 2009

The effect of pesticides on nitrogenase activity in rhizosphere soil from rice fields was investigated. The differential response of insecticides on nitrogenase depended on the method of field application. Results also showed that the differential response to the pesticides of. specific groups of nitrogen-fixing micro-organisms depended upon the method of application.

Soil incorporation of carbofuran stimulated the rhizosphere nitrogenase, while endosulfan and hexachlorocyclohexane inhibited it. Carbofuran and hexachlorocyclohexane stimulated nitrogenase when applied to the standing water. Seedling root dips of isofenphos stimulated nitrogenase, while endosulfan, BPMC and carbaryl showed a variable effect. Quinalphos inhibited nitrogenase irrespective of method of application.
Equations for postnatal chemical composition of the fat-free empty body of sheep and cattle
Authors: Searle T. W. , Griffiths D. A.
Published: March 2009

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.
The effect of Terpal on the yield and yield components of oil-seed rape (Brassica napus L.)
Authors: Chapman J. F. , Scabisbrick D. H. , Daniels R. W.
Published: March 2009

The objective of this study was to examine the effect of the chemical growth regulator Terpal (a mixture of mepiquat chloride and ethephon or 2 chloroethyl phosphonic acid) on the pattern of branching, plant height and yield components of winter oil-seed rape (cv. Jet Neuf). Mepiquat chloride (a quaternary ammonium compound with similar antigibberellin properties to cycocel) was developed as a morphoregulator for cotton where it has been shown to reduce plant height, shorten internodes and increase boll retention (Willard et al. 1977). The activity of ethephon has been attributed to its release of ethylene which influences a wide range of developmental processes, for example fruit abscission and ripening (Chatterjee, 1977; Gvozdenovic, Dulic & Slavic, 1978), growth retardation (Van Andel & Verkerke, 1978) and also the extent of lodging in cereals (Hill, Joice & Squires, 1982).
Studies of the skeleton of the sheep. III. The relationship between phosphorous intake and resorption and repair of the skeleton in pregnancy and lactation
Authors: Benzie D. , Boyne A. W. , Dalgarno A. C. , Duckworth J. , Hill R.
Published: March 2009

1. The ash content of the skeleton of Cheviot ewes fed a daily ration containing about 4·5 g. of phosphorus fell by 18·8% between mid-gestation and mid-lactation, and 2 months after the end of lactation the loss was fully replaced.

2. In ewes fed a daily ration containing about 1·5 g. of phosphorus the loss of skeletal ash was 39·9% at mid-lactation, and this was not replaced 2 months after the end of lactation. When the phosphorus intake was raised in mid-lactation from 1·5 to 4·5 g. repair was greater but was still not complete.

3. Resorption was greater in bones rich in cancellous tissue, such as the cervical vertebrae, than in those rich in compact tissue, such as the shafts of long bones, but when severe resorption took place significant losses were found in the shafts of long bones as well as in other bones.

4. Whole blood inorganic phosphorus values were very low, particularly during lactation, in ewes fed on the low-phosphorus ration. When extra phosphorus was fed from mid-lactation onwards blood phosphorus values rose to normal in less than four weeks, a much more rapid recovery than that which took place in the skeleton.

5. Resorption of the skeletons of ewes on both moderate and low-phosphorus rations could be detected using radiographs taken of the radius in the living animal at mid-lactation, and severe resorption found in ewes fed on the low-phosphorus ration could be distinguished readily from the milder resorption found in ewes fed on the moderate-phosphorus ration.
Sweating in cattle. IV. Control of sweat glands secretion
Authors: Taneja G. C.
Published: March 2009

Two calves (Aberdeen Angus and American Brahman) were used exposed to different combinations of wet- and dry-bulb temperatures in a psychromatric chamber at the Physiology Department of the University of Queensland. These animals were 7–8 months old when first exposed to heat.

Effect of various drugs affecting the sympathetic nervous system (adrenaline, noradrenaline, Dibenamine, Priscol, atropine and acetylcholine) on the rate of cutaneous evaporation in calves was tested. Cutaneous evaporation was measured by means of a capsule before and after the administration of these drugs.

Cutaneous evaporation increased with the introduction of adrenaline and was suppressed by the administration of Dibenamine. Noradrenaline and Priscol had no appreciable effect. Acetylcholine failed to stimulate sweating and atropine did not block the sweat glands.

Sweat glands of cattle were, therefore, found to be functional and their innervation adrenergic. Cattle use sweat to prevent body temperature from rising, yet the amount of sweat secreted is not large enough to allow cattle to maintain thermoneutrality at high air temperatures.