bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of water by six grass species. 2. Root distribution and use of soil water
Authors: Garwood E. A. , Sinclair J. 
Published: March 2009

SUMMARYThe use of soil water by six grasses (perennial ryegrass, cocksfoot, timothy, rough stalked meadow grass (RSMG), tall fescue and Italian ryegrass) was measured over 2 years. The swards were cut either at 3-week (C3) or 6-week (C6) intervals. In both years the maximum soil water deficit attained under C6was greater than under C3. Following several of the cuts from C6there was a marked, although temporary, reduction in the rate of water uptake.An extended dry period in the second harvest year revealed substantial differences in the total water used and in the patterns of uptake from the soil profile by the grasses. Effective depths of utilization of water under treatment C6were: RSMG, 40 cm; timothy, 70 cm; cocksfoot, 70 cm; perennial ryegrass, 80 cm; tall fescue > 100 cm. This order of depth of utilization corresponded with the order of yields obtained during drought conditions. An examination of the root systems of four grasses also showed that, particularly under treatment C6, roots of tall fescue were more numerous at depth than those of timothy, cocksfoot or perennial ryegrass, and under this treatment it showed its greatest tolerance to dry conditions. Drought tolerance in these grasses appears largely determined by the volume of soil exploited by the roots for water.
The influence of diet upon the quantity and types of amino acids entering and leaving the small intestine of sheep
Authors: Harrison D. G. , Beever D. E. , Thomson D. J. , Osbourn D. F. 
Published: March 2009

SUMMARYWether sheep were fed on six forage diets, namely, (1) barn-dried low-N hay, (2) barndried low-N hay plus urea infused intraruminally at 12·6 g/24 h, (3) dried sainfoin, (4) dried lucerne, (5) fresh red clover and (6) dried and pelleted red clover. The proportions of amino acids in the diet and in samples of digesta from the duodenum and ileum were determined.The relative proportions of individual amino acids in the duodenal digesta showed little variation despite the differences in intake and the variation in the proportions of amino acids in the feeds. Only the proportions of methionine, lysine, 2:6 diaminopimelic acid (DAPA) and aminoisobutyric acid (AIB) showed significant (P< 0·01) variation with respect to diet. In the ileal digesta the proportions of methionine, leucine, tyrosine, phenylalanine, glutamic acid, proline, glycine, alanine, AIB and DAPA showed significant variation by diet.With all diets except lucerne the quantity (g/day) of total amino acids presented at the duodenum was higher than the quantity ingested. There was no correlation between the quantity of total amino acids presented at the duodenum and the quantity disappearing within the small intestine.The duodenal digesta contained a significantly higher (P< 0·001) proportion of essential amino acids than did the ileal digesta. This difference was most marked with the diets which supplied a low amino acid intake.With all diets there was little apparent absorption of DAPA in the small intestine.
Magnesium phosphates as dietary supplements for growing sheep
Authors: Fishwick G. , Hemingway R. G. 
Published: March 2009

SUMMARYGrowing wether sheep in metabolism cages were fed a low phosphorus diet (0·75g P/day) supplemented with 1·75 g P/day as either a magnesium phosphate (20·0% Mg, 18·5% P) or a calcium magnesium phosphate (16·1% Ca, 6·0% Mg, 18·5% P). In addition, the magnesium phosphate provided 1·87 g Mg/day and the calcium magnesium phosphate 0·57 g Mg/day. In each case comparisons were made with equivalent amounts of phosphorus and magnesium supplied as dicalcium phosphate (26·5% Ca, 16·0% P) and magnesium oxide (60·0% Mg).All the supplements resulted in similar positive phosphorus retentions of between 0·77and 0·92 g P/day compared with a daily loss of 0·17 g P/day for the low phosphorus diet. Calcium retentions were higher (1·40 and 1·70 g Ca/day) whendicalcium phosphate rather than the magnesium phosphates (1·16 g Ca/day) were given. Magnesium retentions were increased from 0·1 g Mg/day (unsupplemented) to 0·3–0·4 gMg/day and were similar for both magnesium oxide and the magnesium phosphates.Blood phosphorus and magnesium concentrations were increased to a similar degree by all forms of supplementation.
Plant density and yield of grain maize in England
Authors: Bunting E. S. 
Published: March 2009

SUMMARYResults from 10 field experiments are reported. Inra 200, the standard variety in official maize grain trials in Britain, was grown in six of the trials; comparative information was obtained on a range of competitive commercial hybrids and an experimental, early flowering, hybrid. The final plant densities most commonly involved ranged from 5 to 20 plants/m2, with extremes of 2 and 30 plants/m2. The effects of spatial arrangement were also considered in multifactorial or systematic designs; in general, yields increased slightly with more even spacing but no evidence was adduced that spacing, within the limits likely to be encountered in commercial practice, would significantly modify interpretations of density effects.In all varieties tested, a satisfactory model for the response in yield of grain to changes in plant density was 1/y = a + bx + cx2, where y = grain yield/plant and x = density. Estimated parameter values, however, were not the same for all varieties and significant genotype × density interactions were obtained.Grain yield/unit area in Inra 200 was maximal at densities of 8–10 plants/m2, but the response curve did not have a pronounced peak; differences in average yieldat densities ranging from 6 to 14 plants/m2 were less than 6%, and yield at 20 plants/m2 was about 80% of the maximum. Other flint × dent hybrids grown commercially for grain in northern areas (Anjou 210, L.G. 11, Warwick SL 209) reached maximum grain yield/unit area at lower densities (6–8 plants/m2), and the decline in yield with increasing density was much more marked than in Inra 200. In contrast, an earlier flowering, shorter growing, experimental hybrid (ARC 51 A) did not reach maximum yield until density was raised to 14 plants/m2, and was even more tolerant of high plant densities than Inra 200. With increasing plant density the number of ears/plant declined, falling below 1–0 in Inra 200 at densities in excess of 10 plants/m2, and averaging about 0–8 at plants/m2. Over the range 6–20 plants/m2 shelling percentage was reduced by no more than 4%, but water content of the ear (grain plus rachis) increased significantly with density. In the very early hybrid, ARC 51A, the difference in water content of the ear at 6 and 20 plants/m2 was less than 3%, but in Inra 200 it averaged about 8% and in varieties less tolerant of high densities it was often ofthe order of 15%. These results could be related to the delaying effects of increasing density on time of silk emergence. Relatively, time of pollen shed was little affected by density changes. In Inra 200 the difference in time between mid-anthesis and mid-silk was about 7 days more at 20 plants/m2 than at 6 plants/m2 while in Anjou 210 and Kelvedon 59A the comparable increase was 14 days.The practical significance of the findings is discussed in relation to current grain and silage maize production practices, and to future breeding and testing programmes in Northern Europe.
Effect of different doses of 17β-oestradiol on growth and carcass composition of wether and ewe lambs
Authors: Bass J. J. , Fowke P. J. , Duganzich D. M. , Peterson A. J. 
Published: March 2009

SUMMARYSilastic implants of different lengths (0·5–4 cm) containing oestradiol were implanted in wether or ewe lambs, which were slaughtered at 14 or 23 weeks of age. Live weight gain and carcass weight of lambs was increased marginally by oestradiol treatment. Oestradiol decreased the percentage of fat in the carcass, while increasing the percentage of carcass water. Older lambs had a greater response to oestradiol treatment for the weights of the carcass protein and ash. The female reproductive system was affected by oestradiol with the ovarian weights being depressed and the uterine weights increasing. The uterus was especially sensitive to oestradiol at 14 weeks of age. Oestradiol increased the weight of protein in lamb carcasses, especially in the older lambs of this study.
The effect of type of suckling on the pre- and post-weaning lactation performance of Damascus goats and the growth rate of the kids
Authors: Hadjipanayiotou M. 
Published: March 2009

SummaryForty-nine and 58 Damascus goats were used in each of two trials, respectively. Goats were randomly allocated 2 days post-partum to twin-suckling (TS), singlesuckling (SS) and no-suckling (NS) kids treatments. In trial 1, artificially reared kids were divided into two groups fed either on ewe-milk (25·8% fat, 24·2% protein) or on calf-milk (15% fat, 22·5% protein) replacer. In trial 2, all artificially reared kids were fed on ewe-milk replacer. The ewe- and calf-milk replacers were reconstituted in the ratio of 1 part powder to 5 or 4 parts (by weight) of water, respectively.Separation of kids from their dams reduced total milk yield (means of two trials) until weaning (TS 194, SS 176, NS 121 kg/goat) and from weaning to 90 days of lactation (TS 95, SS 89, NS 70 kg/goat). On the other hand, separation of kids increased marketable milk yield until weaning (TS 68, SS 99, NS 121 kg/goat). Marketable milk during the period 3–90 days post-partum was similar for NS and SS goats (TS 163, SS 188, NS 191 kg/goat). Goats suckling two kids suffered greater weight losses (TS 78, SS 44, NS 6 g/day). Goats suckling two males produced more milk until weaning than all other twin sets. Differences in concentrate intake between group means of TS and SS were smaller compared with the NS group (TS 2·26, SS 2·08, NS 1·86 kg/goat per day).There were no differences in weaning weight and weight gain from birth to weaning between kids reared on milk replacers. However, four kids on the calf-milk replacer died and two more were excluded from the data because of severe scouring. Single suckling kids gained more weight until weaning than TS and those reared artificially (AR) on ewe-milk replacer (SS 11·1, TS 9·1, AR 9·3 kg/kid). Furthermore, males consumed more milk than females (males 74, females 64 kg/kid) and SS more than TS kids (SS 75, TS 63 kg/kid).It is concluded that SS and NS treatments increase commercial milk yields compared with the TS goats, but NS should not be recommended because of an adverse effect on pre- and post-weaning lactation performance.
Relationship between bone dimensions and conformation in beef carcasses
Authors: Colomer-Rocher F. , Duganzich D. M. , Bass J. J. 
Published: March 2009

SummaryFrom a mixed group of cross-bred steers slaughtered at the same age, up to 12 carcasses of similar weight from each of the five conformation classes were chosen using the European Economic Community (EEC) scale for the classification of carcasses of adult bovine animals. In the hindquarter of carcasses with better conformation the ratio of muscle to bone was higher with less internal fat and more subcutaneous fat, muscles were heavier and blockier, both the carcass and leg length were shorter. Short-thick muscles were associated with short-thick bones. The results indicate that the EEC scale is a useful method to discriminate between carcasses differing in composition. It is suggested that differences in muscle: bone ratio in cattle could reflect differences in the structure and shape of bones. The conclusions remain tentative until they are confirmed on a larger number of carcasses.
The detection and measurement of mite infestation in animal feed using near infra-red reflectance
Authors: Wilkin D. R. , Cowe I. A. , Thind B. B. , McNicol J. W. , Cuthbertson D. C. 
Published: March 2009

SummarySamples of pig feed, infested to various known amounts with Acarus siro L., were scanned using an NIR analyser. Visual inspection of the spectra of infested feed did not indicate the presence of mites, but principal components derived from these spectra were correlated with the number of mites. Examination of the spectrum of Ringer solution, and of principal components for both infested feed samples and for mites scanned in isolation, indicated that in infested samples mite haemolymph caused the absorbance maximum for water to be shifted towards the visible end of the spectrum. Simpler calibration models, of the type used by current commercial NIR analysers, were developed which were able to detect and quantify economically significant levels of mites in infested pig feed.
Effects of sowing technique on yield formation of Vicia faba as affected by population density, sowing date and plant type
Authors: Stützel H. , Aufhammer W. , Löber A. 
Published: March 2009

SUMMARYField experiments were carried out in which three different sowing techniques: sowing by hand, with a conventional seed drill and with a precision drill, were used to plant an indeterminate and a determinate cultivar of Vicia faba at two sowing dates and at three population densities in 1989 and 1990 in Southern Germany.Delayed sowing reduced field emergence rates in both years. Hand sowing produced the poorest stands in some instances due to an insufficient sowing depth being achieved. Only at late sowing dates did precision drilling give greater field emergence rates than conventional drilling. During the early stages of growth, hand and precision sowing resulted in crops with the greatest light interception and dry matter production. However, these differences between sowing techniques decreased later on. Lodging was most severe in conventionally drilled crops, particularly at high population density. Thus, when lodging occurred, dry matter and grain yields decreased with increasing plant density in conventional sowings, although they tended to increase in hand-sown and precision-drilled crops. Overall, apart from this interaction, there was no significant effect of sowing technique on grain yield. Grain yields and dry matter production were generally higher in the indeterminate cultivar Herz Freya than in the determinate cultivar Ticol, but there were no differential effects of sowing technique.
Effect of herbage in Astrebla spp. pastures in northwest Queensland on lamb survival
Authors: Cobon D. H. , Carter J. O. 
Published: March 2009

SUMMARYExtensive grazing experiments were conducted over four summer breeding seasons in north-west Queensland between 1984 and 1989. Ewes in the last third of pregnancy were grazed on Mitchell grass (Astrebla spp.) pastures of varying forb (herbaceous plant other than a grass) content. Pastures of low forb content (F-) were attained by stocking paddocks heavily with wethers prior to the experiment, or by selecting paddocks which already contained pastures of low forb content. Pastures of high forb content (F+) were kept without animals prior to the experimental period. Pastures comprised a range of forb biomass (29–828 kg DM/ha) and percentage forbs in total biomass (3–49%). Lamb marking percentage was found to be dependent on the biomass of forbs and proportion of forbs in the pasture, in two experiments. Ewes which grazed F+ pastures had lower lamb marking percentages than those grazing F- pastures.Twenty pasture species collected during the experiments were analysed for the ratio of 13C: 12C and photosynthetic pathway was determined. Five forb and all three grass species had C4-dicarboxylic acid pathways, ten forbs had Calvin-C3 pathways and two forbs had crassulacean acid metabolism pathways.Estimates of the proportion of C3 and C4 species in the diet were determined by analysing the ratio of 13C:12C in faeces. The apparent high proportion of Calvin-C3 pathway forbs in the diet of ewes compared to the proportion in the total pasture biomass indicated that ewes preferentially select C3 forbs in the diet, although there was no dependence of lambing percentage on the estimated proportion of C3 forbs in the diet. Management strategies that may improve lambing percentage in the Mitchell grass areas of north-west Queensland are discussed.
Retention of energy and nitrogen by young sheep on different feeding patterns
Authors: Freer M. , Jones D. B. , Christian K. R. 
Published: March 2009

SUMMARYIn each of two experiments the comparative slaughter technique was used to compare the retention of energy by young Border Leicester × Merino wethers when the same total amount of food was offered according to two different feeding regimens. These were designed to simulate, in pens with a diet of pelleted lucerne, feeding patterns typical of continuous and intensive rotational grazing.In the first experiment ten 9-month-old sheep that were offered the same amount of food daily (mean intake 367 g digestible organic matter) during each of 14 weeks made mean daily gains of 39 g live weight, 6·3 g body fat and 0·59 MJ (140 kcal) energy compared with a gain of 30 g live weight, a loss of 1·4 g body fat and a gain of 0·28 MJ (67 kcal) energy by a similar group that ate the same total quantity of food but in amounts that ranged, during each week, from 1·8 to 0·1 times the daily intake of the other group. This cyclic feeding pattern caused a small decrease in the digestibility of dietary organic matter.In the second experiment two similar feeding patterns were compared with ten pairs of 3-month-old sheep eating twice as much food each week as in the first experiment. One member of each pair was, in each of 13 weeks, offered food ad lib. for 3 days and then amounts falling to 20% of voluntary intake on the seventh day; the other one ate the same amount of food each week but in seven almost equal feeds. The latter sheep gained, on average, 132 g live weight daily and retained 58 g body fat and 2·96 MJ (707 kcal) energy compared with 124 g live weight, 49 g body fat and 2·61 MJ (624 kcal) energy by the sheep on the cyclic feeding pattern. In neither experiment was wool growth affected by feeding pattern.The greater effect of the cyclic feeding pattern in reducing the efficiency of energy retention in the first experiment is attributed to the higher number of days each week during which these animals were estimated to be in negative energy balance. These results suggest that adverse nutritional effects of a fluctuating feeding pattern in rotational grazing are likely to be most important where sheep are being rationed near their maintenance level and only small where food is ample.
The growth of maize. I. The effect of plant density on yield of digestible dry matter and grain
Authors: Adelana B. O. , Milbourn G. M. 
Published: March 2009

SUMMARYThree maize hybrids (Kelvedon 75A, Kelvedon 33, and Anjou 210) were grown under irrigated conditions at a wide range of density from 5·4 to 21·6 seeds/m2 at a rectangularity of 1:1. For yield of digestible dry matter at the time of silage harvest (7 October) a seed rate of 10·8 seeds/m2 (44000/acre) appeared adequate, as doubling the density to 21·6/m2 only resulted in 7% higher yield. K 33, which is a late·maturing hybrid bred for silage in south-east England (50·5–52·5 °N) produced the highest total yield of digestible dry matter due to a high yield of digestible stem. However, the dry matter % of this material would be too low for good ensilage and for a high level of feed intake. In the early grain hybrid K 75 A, 62% of the digestible dry matter was contained in the ear at the silage stage which improved the digestibility and dry matter % of the whole crop with only a 12% lower yield than K 33.The optimum density for grain was 10·8 seeds/m2. This is a higher response to density than is believed to occur in field crops in Britain as in these experiments the seed was planted on the square and irrigation was applied at moisture sensitive stages. The parabolic relationship between grain yield and density was closely related to grain number per unit area. At 10·8 seeds/m2 all three hybrids were of similar yield and grain number per unit area. In Anjou 210 this was achieved with one large ear per plant, whilst for the two Kelvedon hybrids mean ear production was 1·34/plant but with 27% fewer grains per ear.
A study of the herbage intake and efficiency of feed utilization of grazing cattle previously fed two winter planes of nutrition
Authors: O'Donovan P. B. , Conway A. , O'Shea J. 
Published: March 2009

SUMMARYAn experiment was conducted using 36 Hereford × Shorthorn bullocks of about 350 kg initial live weight. Winter planes of nutrition 13 December to 23 March were ‘low’ (hay only) and ‘medium’ (hay plus 1·8 kg concentrate); the former group of 18 bullocks lost on average 21·5 kg while the latter gained 26·5 kg. Each group was then stocked at 2·5 (low), 4·3 (medium) and 6·2 (high) bullocks per hectare and rotationally grazed on 10 plots, 7 of which contained H.I.-white clover mixture and the remaining 3 contained permanent pasture. Pasture digestibility and intake were determined for 16 weekly periods between early April and the end of September. Organic matter digestibility (OMD) of grazed herbage was determined in vitro on samples obtained by means of two rumen-fistulated bullocks. One gelatin capsule containing about 10 g of chromic oxide was daily administered to each bullock to estimate organic matter output. Winter feeding planes had no significant effect on OMD, and increasing the stocking rate increased herbage OMD only during the final 6 weeks. Significantly more organic matter was ingested during the grazing season by animals which had previously been fed on a low plane of nutrition. Stocking rates also significantly affected OMI. Bullocks fed on a low plane during winter were slightly more efficient subsequently in converting herbage into live-weight gain but this was a reflection of their lower average body weight; when feed efficiency was expressed on the basis of metabolic size, bullocks fed on a medium plane were more efficient in converting feed to live-weight gain. It is concluded that the higher daily gains on pasture of bullocks previously fed on a low plane is largely the result of a significantly higher feed intake by these animals.
Statistical research on the digestibility in the cow. I. Dry matter and energy
Authors: Paquay R. , De Baere R. , Lousse A. 
Published: March 2009

SUMMARYThe results obtained for dry matter and energy digestibility with 116 different rations fed to 242 non-pregnant dry cows and 96 laotating cows were studied.With winter rations, dry-matter digestibility (Y) is linearly related to dry-matter intake (X1) and to the crude fibre content of the dry matter (X2):Y = 89·58–0·557X1–0·863X2.A similar equation was obtained for energy digestibility (Y):Y = 90·68–0·195X1–0·892X2,where X1 represents the energy intake (in 1000 kcal) and X2 the crude-fibre content.Digestible dry matter or energy can be estimated very accurately from dry matter or energy intake and from crude-fibre content.There is a highly significant linear relation between dry matter or energy digestibility and nitrogen concentration of the faeces, especially with grass.Dry-matter digestibility is also influenced by the physical form of the feeds and by individual factors.
Resistance in white cabbage to necrosis caused by turnip and cauliflower mosaic viruses and pepper-spot
Authors: Walkey D. G. A. , Neely Heather A. 
Published: March 2009

SUMMARYCabbage accessions were screened for resistance to turnip mosaic (TuMV) and cauliflower mosaic (CaMV) viruses in glasshouse and field tests. None was immune to infection by either virus, but some were highly resistant to one or both viruses. TuMV induced severe necrotic lesions on the outer leaves of susceptible plants at harvest, and this was associated with severe internal necrosis in heads stored for 8 months at 0–1 °C. This correlation was not observed in CaMV infected plants. Pepper-spot necrosis was low in stored heads of some accessions but high in others.