bluuebunny/crossref_metadata_2025_split huggingface dataset:
Body composition studies with the milk-fed lamb. I. Chemical composition and calorific content of the body and organs of newly-born lambs
Authors: Jagusch K. T. , Norton B. W. , Walker D. M. 
Published: March 2009

SUMMARYThe total body content of fat, protein, ash, moisture and energy of 43 male cross-bred lambs was determined after the lambs had suckled the ewe at pasture for between 2 and 5 days. Sixteen lambs were dissected into seven compartments, namely, carcass, skin, wool, blood, viscera (two groups) and vastus lateralis muscle, and the chemical composition of each was determined. The heats of combustion of the fat and fat-free tissues were also determined. The relationships between empty body weight and body and organ composition were described by logarithmic regression equations.
The body composition of 3-month-old Rambouillet lambs of different live weights
Authors: Epstein H. , Herz A. 
Published: March 2009

SummeryCarcass measurements were made on 24 Rambouillet lambs of different live weights but of the same age, and the lambs divided into 3 groups of 8 according to live weight. Group I, with the lowest mean live weight, had the lowest dressing percentage, relatively heaviest head and feet and lightest pelt, while group III, with the highest mean live weight, had the highest dressing percentage, the relatively lightest head and feet and the heaviest pelt of the three groups.Group I contained the lowest percentage, and group II, of medium live weight, the highest percentage of muscle, while the relative weights of bone and fat tissue were similar. Group III contained the highest percentage of fat tissue and the lowest percentage of bone. The differences in the relative weights of the edible internal organs between the three groups were not significant.Testis weight was relatively much greater in Group III than in the lighter animals. While dressing-out percentage increased with body weight, the increase was not equally distributed between fore and hindquarters. Hindquarters were relatively larger in group II than in group I; but the forequarters accounted for the greater part of the differences between groups II and III.
The structural carbohydrates and the in vitro digestibility of a ryegrass and a cocksfoot at two levels of nitrogenous fertilizer
Authors: Waite R. 
Published: March 2009

SUMMARY‘Nitro-chalk” was applied to established swards of ryegrass S. 24 and cocksfoot S. 37 at the rate of 24 and 96 lb N/acre (27 and 107 kg N/ha) before growth commenced and after each cutting. The cuts were taken each time the grass reached a length of 10–11 in (8–9 in of cut herbage). The main effect was that the higher rate of fertilization allowed the grass to be harvested more frequently and this grass had lower pectin, cellulose and hemicellulose contents and a higher level of digestibility. A secondary effect was that the proportion of hemicellulose to cellulose was less in the more heavily fertilized grasses. The cocksfoot grasses at both levels of fertilizer were cut more frequently than the corresponding ryegrasses and were only slightly less digestible. There was some decline in the digestibility of the grasses from May to September which was associated with lengthening growth intervals and generally higher percentages of the structural constituents.
Production characteristics of the Jamaica Hope breed of dairy cattle
Authors: Wellington K. E. , Mahadevan P. , Roache K. L. 
Published: March 2009

SUMMARYThis study is the first comprehensive estimation of breed parameters for the Jamaica Hope breed of dairy cattle. It has shown that the breed has considerable potential for milk production undser good husbendry in a tropical environment. Improvements in reproductive performance may be achieved, without prejudice to production performance, by using milk yield per day of calving interval (which has a moderatoly high repestability) as a criterion for selection.
Voluntary intake of food by mature sheep following restricted feeding
Authors: Keenan D. M. , McManus W. R. , Freer M. 
Published: March 2009

SUMMARYNine Merino wethers were used in a cross-over experiment to compare the voluntary intake of three diets after a 4-week period in which the intake of the same diets was restricted, either to a level which maintained the live weight and energy status of the sheep, or to one which resulted in losses of 18% and 26% in their live weight and total energy content respectively. The diets were prepared from lucerne hay; chaffed (L), ground and pelleted (P) and pelleted after mixing with ground wheat (W).The voluntary intake of food increased only slowly during the 4 weeks after restrictions were removed; the total intake of digestible organic matter from diets W, L and P was in the ratio 100:122:146. Differences between diets L and P, but not W, were associated with their rates of disappearance from the rumen. Sheep which had been severely restricted ate less food during the first fortnight and no more during the second fortnight than those which had previously maintained their energy status. The difference in the first fortnight was less for diet P than for diet L. The process of adaptation by the sheep to unrestricted feeding was associated with an increase in the net rate of disappearance of volatile fatty acids from the rumen.Sheep offered food ad lib. after a period of submaintenance feeding gained more weight than sheep which had previously been fed to maintain weight and this increase was greater with diet P than with diet L. However, the differences in live-weight change consisted largely of water in the gut and did not result from a relative increase in the voluntary intake of food or in the efficiency of energy utilization.
Potassium uptake by potatoes
Authors: Addiscott T. M. , Mitchell J. D. D. 
Published: March 2009

SUMMARYPotatoes (var. Pentland Dell) were grown in pots containing soils from the Bothamsted ley–arable experiments. When about half the initially available K was used, the tops were harvested and the potential limiting K uptake, inferred from K uptakes, was – 4150 cals/equiv. The plants grew on until they exhausted the available K and died, having set tubers. The potential then limiting K uptake, inferred from total K uptakes, was – 4900 cals/equiv., similar to the mean potential in the exhausted soils, – 4710 ± 61 cals/equiv. The significance of these measurements is discussed.Total K uptake was closely related to the amount of K that had to be removed from each soil to lower the potential to – 4900 cals/equiv. and the relationship suggested that the potatoes did not use any K from initially non-available reserves.Dry-matter yields of tubers and of tops + roots, and the ratio of the two, were well related to quantity and potential of K in the soil; tuber yield was also well related to K in tops. The K potential needed for maximum yield of tubers exceeded – 2430 cals/equiv.
The evaluation of cattle foods and diets in terms of the ruminal concentration of volatile fatty acids I. The effects of level of intake, frequency of feeding, the ratio of hay to concentrates in the diet, and of supplementary feeds
Authors: Bath I. H. , Rook J. A. F. 
Published: March 2009

1. A study was made of the effects of feeding regimen and the composition of the diet on the ruminal production ofV.f.a.'S in cattle.2. The day-to-day variations in the pattern of rumen fermentation in cows given a diet of hay and concentrates indicated that within-cow differences in the molar proportions of the acids from diet to diet are of significance if they exceed about 3% (of the mean value) for acetic acid, about 10% for propionic and butyric acids, and about 25% for valeric acid. The results emphasized also the important differences to be found between cows given the same diet.3. A change in the frequency of feeding from once to four times daily at a constant daily drymatter intake had little effect on the daily mean values for pH, concentration of totalV.f.a.'S, or the molar percentages of the individual acids, but almost invariably decreased the range of values observed between feeding.4. With diets of hay and of hay and concentrates an increase in daily dry-matter intake was associated with a fall in pH and an increase in the concentration of totalV.f.a.'S; with the diet of hay and concentrates there was a considerable decrease in the molar percentage of acetic acid and a corresponding increase inN-butyric, but there was little change in the molar percentages of the acids with the diet of hay.
Partial inhibition of nitrate production by products of the mineralization of soil organic matter
Authors: Lewis D. G. 
Published: March 2009

1. Soil samples were incubated at 60% W.h.c. at 20° C. and leached after 8 and 20 weeks. On subsequent incubation, the rate of nitrate production in the leached samples was greater than that in unleached control soils. The increase in nitrate production seems to be due to an increased rate of ammonification.2. Adding 100 p.p.m. of nitrate nitrogen to the soil before incubating had no effect on mineralization.3. Adding a leachate of incubated soil to new soil samples reduced the rate of mineralization on incubation. This reduction is not due to nitrate or any other anion, since deionized leachate was equally effective.
Effects of conventional daily magnesium supplementation, breed of ewe and continued potassium fertilizer applications on plasma magnesium and calcium levels of ewes
Authors: Ritchie N. S. , Hemingway R. G. 
Published: March 2009

1. Muriate of potash applied at rates of 0, 1 and 2 cwt./acre to herbage which had also received similar treatments in the previous year did not influence plasma magnesium or calcium values in lactating ewes.2. 24 Cheviot ewes had slightly lower plasma calcium and magnesium levels than 24 Half-bred ewes of the same age both before and after lambing.3. 6·6 g. of magnesium oxide given as a daily drench did not increase plasma magnesium values as measured by blood samples taken 24 hr. after drenching. Values were however increased by 0·5 mg. Mg/100 ml. four hours after drenching.4. No clinical cases of hypomagnesaemic tetany occurred, even although the mean plasma magnesium level of all the ewes in the experiment was only about 1·0 mg./lOO ml.5. Plasma magnesium values of ewes before lambing were significantly (P < 0·001) correlated with post-lambing levels. Values for the ewes during 1962 were equally significantly correlated with levels for the same sheep at comparable dates in 1961.
The nutritive value of Panicum maximum (Guinea grass) II. Digestibility by cattle and water buffaloes, related to season and herbage growth stage
Authors: Johnson W. L. , Ordoveza A. L. , Hardison W. A. , Castillo L. S. 
Published: March 2009

Fifteen digestibility trials were conducted in the wet, early dry, and late dry seasons in the Philippines. Panicum maximum (guinea grass) was fed at growth stages of 1–4 months to Bos taurus (Holstein), Bos indicus (Red Sindhi), and Bos bubalis (water buffalo) bulls.Significant differences were shown between digestibility coefficients from water buffaloes and those from Holstein cattle, the former having a 5–7 % advantage in most cases. Ratios of volatile fatty acids in rumen fluid from the two species were not different. Separate tables of digestible protein, TDN and digestible energy values for guinea grass were computed for cattle and water buffaloes.
The effects of nitrogen and irrigation on timothy (Phleum pratense) grown for production of seed: II. Reproductive growth and yield of seed
Authors: Lambert D. A. 
Published: March 2009

1. Plants of S.48 timothy were established on a 1 ft square (30 cm × 30 cm) pattern for production of seed. Plots at three levels of applied nitrogen, 0 (N0), 87 (Nl) and 261 (N2) lb N/acre (0, 97·5 and 292·5 kg/N ha) per annum were either irrigated to field capacity from 1 week before initiation of spikelets until 2 weeks before harvest, or not irrigated, during each of three years.2. Application of nitrogen caused earlier initiation and emergence of inflorescences each year, and earlier general anthesis in the first and third years. Irrigation generally had no effect on the date of initiation, but it prolonged the period of reproductive development and delayed the date of harvest by 2–5 days.3. The number of ears per plant was increased by the N1 treatment above the number produced by plants in the N0 treatment. In the N2 treatment the number of ears per plant was between the number in the N0 and N1 treatments in non-irrigated plots; in irrigated plots, plants in the N2 treatment sometimes had a lower number of ears than plants in the N0 treatment. The length of ears increased with the rate of application of nitrogen.
Studies on the sowing date of cotton in the Sudan Gezira: III. The effect of sowing date on yield and quality under different fertilizer and spraying treatments
Authors: Jackson J. E. , Faulkner R. C. , Schultz L. Razoux 
Published: March 2009

Field experiments from 1959–60 to 1963–4 showed that when blackarm resistant strains of Egyptian type cotton were sown around the beginning of August and adequately protected from fleabeetle, the resultant crop was of higher yield and considerably better average quality than that from the normal mid-to-late August sowings. Effective length, maturity ratio, standard fibre weight, bundle strength and lea-count × strength product were all improved. Sowing in early July, tested in one season only, gave rather better quality but lower yield than sowing in early August. Sowing in late August or in September depressed both yield and quality. The importance of direct climatic effects and of blackarm, fleabeetle, bollworm, other insect pests and wilt in controlling the choice of, and response to, sowing date is briefly discussed.Thanks are due to the Sudan Gezira Board for kindly supplying the results of the large-scale sowing date trials and for the grading of experimental cotton, to the Shirley Institute of Manchester for the fibre and spinning tests and to the Chief, Agricultural Research Division, Ministry of Agriculture, Sudan, for permission to publish this paper.
Voluntary intake of low-protien diets by ruminants: I. Intake of food by cattle
Authors: Elliott R. C 
Published: March 2009

1. A study was made of the voluntary intake hay, of low nutritive value, by heifers of two breeds of African cattle when given four different amounts concentrate foods (9, 18, 27 and 36 g/kg W0.73/day) each providing three levels of protein (1·3, 2·6 and 3·9 g DCP kg W0.73/day). The trial was designed two incomplete Latin squares, one for each breed, with thirteen treatments, thirteen heifers and four replicates.2. Voluntary intakes of low-protein hay by Africander and Mashona heifers were similar and these increased as levels of supplementary protein were raised and intakes of hay were reduced amounts of concentrate provided to them became more liberal. Inter-relationships of food intake and dietary composition were, however, very complex.3. Increased allowances of dietary protein and concentrate generally corresponded with higher intakes of total food and digestible energy. But this was not true at the lower levels of protein input where there was evidence that food and digestible nutritient intakes were depressed when liberal amounts of concentrate were fed to the cattle.
The use of coarsely chopped barley straw in high concentrate diets for beef cattle
Authors: Forbes T. J. , Irwin J. H. D. , Raven A. M. 
Published: March 2009

SummaryAn experiment was carried out in which the performance of cattle given diets containing 20 and 40% of coarsely chopped straw (1–3 in lengths) was compared with that of similar cattle given an all-concentrate diet. Each diet was offered ad libitum and twelve Hereford cross steers and twelve Friesian steers were used in the experiment. The live-weight gains and food conversion ratios were significantly better for the Hereford cross animals but there was no significant difference in over-all dry matter intakes. When the combined response of both breed types was considered there was a significantly linear decrease in live-weight gain with increasing straw intake, to the extent of 0.95 kg per week for each 10% increase in straw intake up to 40% in the diet. Similarly there was a significant increase in the conversion ratios of dry matter (P < 0·01) and organic matter (P < 0·01) with increasing straw intake. The effect on the dry matter conversion ratio was an increase of 1·67 units for each 10% increase in straw intake.Two digestibility trials were carried out, one with coarsely chopped straw and one with coarsely milled straw, the levels of straw in the diets being the same. There was a slight decline in the digestibility of most constituents associated with milling but reductions were not very pronounced. A treatment was included in the second trial in which milled straw was included at 20% of the diet without maintaining the over-all crude protein content of the diet. The apparent digestibility of the organic matter was 5 percentage units lower with this treatment than with that containing the same level of straw in which the level of protein had been maintained.
The effect of sowing and harvesting dates, plant population and fertilizers on seed yield and quality of direct-drilled sugar-beet seed crops
Authors: Scott R. K. 
Published: March 2009

SummarySixteen field experiments made between 1963 and 1967 on direct-drilled sugar-beet seed crops compared the effects of cultural practices on the yield and quality of seed. Sowing in July gave earlier flowering and ripening than sowing in August and usually increased yields, cluster size and percentage germination. Downy mildew was sometimes more prevalent in late sowings.Seed yields increased as the crop changed colour from green to yellow and percentage
germination increased greatly as more clusters contained ‘mealy’ rather than ‘milky’ perisperm. Because of natural shedding and bird damage, seed yields then decreased and losses of 0·6 cwt/acre/day were recorded for early ripening treatments. Cluster size and percentage germination continued to increase while yield was decreasing. Crops ripened a month earlier in 1967, the ‘earliest’ year, than in 1965, the latest year.Crops grown in rows 10 in apart lodged less than those sown 20 in apart, ripened earlier and produced, on average, 3 cwt/acre more seed, which was slightly smaller. In one experiment rows 5 in apart gave similar yields but smaller clusters than rows 10 in apart. Row width had little effect on percentage germination. Increasing the distance between plants in the row gave smaller yields with wider spaced rows, but with narrow rows plants 6 in and 12 in apart yielded more than those 2 in apart. Yields from a plant population of 52,200 plants/acre were 4 cwt/acre greater when plants were 12 in apart in narrow (10 in) rows rather than 6 in apart in wide (20 in) rows. Spacing further apart in narrow rows increased seed size. In wide rows many plants 12 in apart lodged, made secondary growth and produced small, late maturing clusters, of which few germinated.Response to fertilizer nitrogen applied in spring was less, and less was needed for maximum yield on the thin Cotswold soils than on the silty clay loam in Lincolnshire, where it doubled yield in 1966. Phosphate and potash applied in spring had little effect on
yield. Usually fertilizers had no effect on cluster size or germination percentages, but
1·6 cwt/acre N given to a late-ripening crop in 1965 decreased seed size and germination.Ramularia leaf spot, which defoliated crops in the Cotswolds, was worst on early sown and closely spaced plants, and was unaffected by fertilizer.
Experiments on the nutrition of the dairy heifer: VII. Observations on the effect of the energy intake on the utilization of protein in growth and in lactation
Authors: Broster W. H. , Tuck Valerie J. , Smith T. , Johnson V. W. 
Published: March 2009

SUMMARYEight feeding trials on cattle showed that the response in live-weight gain was curvilinear when protein or energy level was varied independently in rations based on poor quality roughages to which cereals and groundnut were variously added to give a range of protein and energy intakes. Live-weight gain was increased by 0·12 lb/day for each 0·1 lb additional digestible crude protein/day at levels of intake below 0·7 lb/day and by 0·03 lb/day at higher levels. It was increased by 0·4 lb/day for each additional 0·1 lb starch equivalent daily/100 lb live weight at total intakes below 0·9 lb daily/ 100 lb and by 0·2 lb/day at higher levels. Over the range 0·5–2·0 lb digestible crude protein daily and 0·7–1·2 lb starch equivalent daily/100 lb live weight the effects of these nutrients were additive.A Latin square nitrogen balance trial demonstrated that a portion of the nitrogen from a protein supplement was retained in the body despite the excretion of the greater part of it in the urine and a further part in the faeces. Nitrogen retention was increased by a supplement of readily available energy through a decrease in urinary nitrogen loss. Nitrogen balance was not increased by a supplement of a fibrous energy source because this induced an increase in faecal nitrogen loss.In a further feeding trial milk yield was found to be affected in a similar manner to growth. At a yield of 30 lb/day the response per lb starch equivalent added to the diet was 0·5 lb milk including 0·05 lb solids not fat and to an increase of 0·1 lb digestible crude protein daily it was 0·25 lb milk including 0·025 lb solids not fat.
The apparent behaviour of maize and sorghum stomata during and after drought
Authors: Glover J. 
Published: March 2009

Maize stomata are shown to be markedly affected by severe drought lasting about a week or more, in that they do not recover their apparent pattern of normal behaviour after the water supply to the plant is restored, although the leaves regain their turgidity and seem normal. On the other hand, sorghum stomata recover well from severe drought lasting 14 days and their recovery follows fairly closely behind the restoration of turgidity to the leaves. It is suggested that this difference in ability of stomata to recover from severe drought in some measure accounts for the superiority of sorghum as a grain crop in dry regions.Severe drought in maize is shown to be less damaging to the young plant than to the old, because the stomata of the unopened leaves behave normally when unfolded after the drought is broken.
Effect of previous cropping and manuring on the nitrogen fertilizer needed by sugar beet
Authors: Draycott A. P. , Last P. J. 
Published: March 2009

SUMMARYSix field experiments made between 1960 and 1968 determined the effect of previo cropping and manuring on the nitrogen requirement of sugar beet. Three were at Silsoe in Bedfordshire on soils developed over Lower Greensand and Gault Clay and three were at Broom's Barn (Suffolk) on Calcareous Drift soils over chalk. Each experiment lasted 2 years, a preparatory crop followed by sugar beet.Spring barley and potatoes were treatment crops in all the experiments and winter wheat, a ryegrass ley and barley undersown with trefoil were included in the Suffolk experiments. Nil, 0·6 or 1·2 cwt N/acre was tested on the sugar beet in the first three experiments and 0, 0·5, 1·0 or 1·5 cwt N/acre in later ones.All the experiments showed that previous cropping influenced the nitrogen requirement of the sugar beet. There was a linear relationship (r = – 0·86) between the amount of fertilizer nitrogen given minus that removed by the preparatory crop, and the quantity of nitrogen fertilizer needed by the sugar beet for maximum sugar yield. Sugar beet grown after barley or potatoes (each given 0·5 cwt N/acre) needed on average 1·0 cwt N/acre at both Broom's Barn and Silsoe for maximum sugar yield. Sugar beet after winter wheat or a ryegrass ley also needed 1·0 cwt N/acre at Broom's Barn. When the previous potato crop was given 1·5 cwt N/acre, 0·5 cwt/acre sufficed for maximum yield of sugar at both centres; also after ploughed-in trefoil, sugar beet needed only 0·5 cwt N/acre.