bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of prostaglandin analogue Cloprostenol on oestrus, ovulation and embryonic viability in sheep
Authors: Trounson A. O. , Willadsen S. M. , Moor R. M.
Published: March 2009

The effect of a single injection of 100 μg prostaglandin analogue Cloprostenol, during the luteal phase of the oestrous cycle was examined for synchronization of oestrus, time of ovulation and embryonic viability in ewes.

Following injection of Cloprostenol alone, 84% of ewes were detected in oestrus 29–48 h later. Pretreatment with PMSG increased the proportion of ewes in oestrus within 36 h. In these ewes 38% had begun ovulating 30 h after the onset of oestrus and by 36 h 87% had begun ovulating. Normal embryos of 8-cells to blastocysts were obtained from ewes given PMSG and Cloprostenol, and on transfer to recipient ewes, treated with Cloprostenol, all recipient ewes produced lambs.

It is concluded that injection of 100 μg Cloprostenol is an efficient method of synchronizing oestrus in ewes and that normal embryonic development would be expected in mated ewes following this treatment.
Urinary allantoin excretion and digestible dry-matter intake in cattle and buffalo
Authors: Vercoe J. E.
Published: March 2009

A linear relationship between the amount of allantoin excreted in the urine of cattle and the digestible dry-matter intake, has been found for cattle fed different roughage diets. The relation was also linear for buffalo although they excreted less urinary allantoin than cattle at the same level of digestible dry matter intake. It is postulated that the relationship arises because of the contribution that degraded microbial nucleic acids make to the excreted allantoin in the urine of cattle.
Weed control of irrigated peanuts in an arid zone
Authors: Amir J. , Lifshitz N.
Published: March 2009

Weed control in irrigated peanuts was evaluated under arid conditions over an 8-year period. Weed competition during the first 8 weeks of the growing season, affected the yield in three out of eight experiments. Mechanical cultivation and herbicides alone or in combination did not control the weed population completely. The best weed control was accomplished by the combination of two herbicides, a system which allowed a complementary effect and long-term control of annual weeds.
High loss of nitrogen in drainage from soil under grass following a prolonged period of low rainfall
Authors: Garwood E. A. , Tyson K. C.
Published: March 2009

When high rates of fertilizer N are applied to grass in an area of low rainfall, considerable amounts may be lost to drainage in the subsequent winter if the N is not fully utilized owing to dry soil conditions during the growing season (Garwood & Tyson, 1973). The data now presented were obtained from the lysimeters described in that paper. The soil is a sandy loam, overlying chalk. The swards of perennial ryegrass (Lolium perenne cv. S. 23) were cut four times each year. Two rates of N were applied as ammonium nitrate (Nitrana), 250 kg (LN) and 500 kg N/ha per year (HN). Two-fifths of this N were applied in March and one-fifth after each of the first three cuts.
Effects of sowing date on the growth, yield and quality of okra (Abelmoschus esculentus (L.) Moench.) in southern Nigeria
Authors: Iremiren G. O. , Okiy D. A.
Published: March 2009

Two varieties of okra were sown at approximately 14-day intervals from 1 April to 1 June for 2 years during the main rainy season in Nigeria. Low soil temperature and moisture, which resulted from a combined effect of high solar radiation, high atmospheric temperature and low rainfall, led to poor seedling emergence at the early sowing dates.

The growth of the fewer plants of the early sowing dates were more vigorous than those of later sowing dates and they attained 50% flowering earlier and had a longer harvest duration. This resulted in increases in number of pods per plant, pod length, pod diameter, pod volume, pod weight and pod yield per ha, indicating compensatory growth by the fewer plants in the early plantings. The relatively lower values obtained for these variables with the late sowing dates were also attributed to possible poor soil aeration arising from the increased rainfall during their growth period.

Sowing dates did not generally affect the percentage moisture, oil and protein in the pods. The effects of varieties on the variables measured were more uniform than those of sowing dates and mostly not significant.
The use of double haploids for detecting linkage and pleiotropy between quantitatively varying characters in spring barley
Authors: Caligari P. D. S. , Powell W. , Jinks J. L.
Published: March 2009

The relationships between pairs of characters are investigated using F1 and F2 derived doubled haploids as well as single seed descent lines from spring barley (Hordeum vulgare) crosses. It is shown that linkage disequilibrium and pleiotropy are factors affecting the relationship between characters in barley. In fact, the linkages found are in general in the coupling phase and pleiotropy is usually positive. The consequences of such relations for plant breeding are discussed.
The distribution of carboxymethylcellulase between fractions taken from the rumens of sheep containing no protozoa or one of five different protozoal populations
Authors: Coleman G. S.
Published: March 2009

The distribution of carboxymethylcellulase (CMCase) between various rumen fractions has been determined at three times after feeding in sheep containing no ciliate protozoa or five different protozoal populations. The total rumen CMCase was lowest in defaunated animals and tended to be higher in animals containing the amylolyticEntodinium caudatumor a natural mixed protozoal population and highest in sheep containing single cellulolytic species. In animals containing the cellulolytic species,Epidinium ecaudatum caudatumorEudiplodinium maggii, 70% of the CMCase was associated with the protozoal fraction whereas less than 15% was present in a fraction prepared in the same way from sheep containing no protozoa or onlyEntodinium caudatum. The activity associated with the free bacteria was higher in sheep containing onlyEntodinium caudatumthan in defaunated animals or those containing the cellulolytic species. Similar results were obtained 1·5, 6·5 or 24 h after feeding. Almost no activity was present in the cell-free rumen liquor under any condition. A variable amount of CMCase (up to 25% of the total) was associated with the plant debris in the rumen and the specific activity of the enzyme released by sonication was often higherthan that released from the free bacteria under the same conditions.
Inflorescence development and seed production inLoliumspp. ×Festuca pratensistetraploid hybrids
Authors: Cremades P. , Bean E. W.
Published: March 2009

The reproductive development and seed production characters of aLolium multiflorum×Festuca pratensistetraploid hybrid and aLolium perenne×Festuca pratensistetraploid hybrid were compared with those of their tetraploid parental cultivars. Experiments were carried out under glasshouse and natural conditions; single plants were studied as only small quantities of seed were available from the breeder. The lowtemperature/short-day requirements for inflorescence induction of the two hybrids were in between those of the corresponding parental species. The variance of the date at which vegetative primordia changed to the reproductive condition was greater in the hybrids than in the parental cultivars, but the variance of the dates of inflorescence emergence were similar for the hybrids and parental cultivars. Inflorescences ranged from theLoliumtype with only sessile spikelets to theFestucatype with primary branches. Inner glumes, which are absent in theLoliumparents but present inFestuca pratensis, were found in the hybrids, though not in all spikelets. In theLolium perenne×Festuca pratensishybrid pollen release, potential pollen viability and floret fertility were low, but theLolium multiflorum×Festuca pratensishybrid produced large amounts of pollen with a higher potential viability and had floret fertilities similar to those of its two parental cultivars. There was sufficient variation in reproductive characters for further selection, particularly in theLolium perenne×Festuca pratensishybrid.
Pasture productivity in Nigeria: II. Voluntary intake and herbage digestibility
Authors: Oyenuga V. A. , Olubajo F. O.
Published: March 2009

The organic-matter intake and the digestibility of grazed tropical pasture mixtures were assessed by the chromic oxide-faecal organic matter-nitrogen technique in five digestion trials. The pasture treatments were designated as: H, Cynodon nlemfuensis var. robustus in a mixture with the legumes Centrosema pubescens and Stylosanthes gracilis; J, Pennisetum purpureum in a mixture with the two legumes in H; K, treatment J plus Panicum maximum; L, a mixture of all the grass and legume species in treatments H, J and K.

The mean organic-matter digestibility of the herbages was determined in indoor digestion trials during the experimental period and varied from approximately 60·0 ± 1·73% to 62·7 ± 4·18% in treatments K and H respectively, with treatments J and L falling between these two values. The mean digestibility of the herbage as grazed, however, was approximately 66·8 ± 1·72, 69·7 ±7·68, 67·1 ± 4·40 and 67·4 ± 4·15 % for treatments, H, J, K and L respectively.

The estimated mean intake of organic matter was somewhat lower, while that of the digestible organic matter was appreciably lower than those reported for animals of corresponding live weights in temperate countries. Grazed pastures were better digested by 4·1 digestibility units in treatment H, by 7·1 in both J and K, and by 5·3 units in L, compared with the indoor digestion trials.

More intensive studies are still needed to warrant any justifiable conclusion as to whether the low intake of herbage by tropical cattle is due primarily to the high crude fibre and the low nutritional values of the pastures, or to the inherent capacity of the animals conditioned to grazing poor·quality pastures.
Genotype-environment interaction – a challenge for plant breeding
Authors: Hill J.
Published: March 2009

Much has been written and said about genotype-environment (GE) interactions and the particular problems which they pose for plant breeders. It is not the purpose of this article to dwell upon every aspect of this story, but rather to discuss how these problems came to be recognized, to comment upon the various techniques which have been employed in seeking a solution to them and to suggest what developments might lie ahead.
Merino birthcoat fibre types and their follicular origin
Authors: Burns Marca
Published: March 2009

The great majority of the fibre-type arrays from the backs of eighty Merino lambs were Plain (including Coarse Plain); Plateau and other arrays also occurred. In most samples no medulla could be seen in the pre-natal parts of halo-hairs examined in benzene, but the presence of medullary substance was demonstrated. All HH were shed and apparently replaced by fine fibres. The shape of the tip curls of early CT fibres in some samples altered with age, apparently by 'setting' in a line of yolk. HH grades ranged from I to VII and there were probable strain differences in grade and medullation.

A total of 599 primary and 2595 secondary follicles and their fibres were identified by dissection. Primary follicles contained HH, SS, Sk, or early CT fibres, secondary follicles only CT or Hi. Sickle fibres commonly occupied most of the PL follicles except where the array was Plateau.
The effect of protein level in creep feed on the growth rate and body composition of sucking pigs
Authors: Whitelaw Anthea W. W. , Elsley F. W. H. , Jones A. S. , Boyne A. W.
Published: March 2009

1. Three creep feeds containing 14, 18 and 22% crude protein of similar protein quality (as measured by total lysine and total methionine plus cystino content) but with similar levels of other nutrients were given ad libitum to 210 pigs, the progeny of thirty large White sows from 21 to 56 days old.

2. At 21 days old, each litter was reduced to seven piglets by killing one, two or three pigs at random. The whole pig was analysed for protein, ether extract, ash and dry matter.

3. At 56 days, 3 further pigs were killed in each litter and analysed in a similar manner.
Interaction between chick peas (Cicar arietinum Linn.) genotypes and strains of Rhizobium sp.
Authors: Rai R. , Singh S. N.
Published: March 2009

Five strains of Rhizobium sp. were studied in vivo for their nodulation capacity, leghaemoglobin content of nodules, crude protein and four amino acids content in five genotypes of chick pea in calcareous soil. Inoculation with Rhizobium led to a significant increase in grain yield compared with the uninoculated control. Genotype C 235 gave significantly higher grain yield than the others. The interactions between strains and genotypes were significant. Genotype C 235 gave maximum grain yield (2·2 t/ha) when treated with strain KG 41. Genotype C 235 exhibited maximum leghaemoglobin content and amino acids.
The growth and development of the beef qualities of Angoni cattle (East African zebu)
Authors: Walker C. A.
Published: March 2009

The development of a community may rightly be said to be reflected in its meat requirements. Primitive peoples are quite satisfied as long as their bulk needs are met, irrespective of quality. This condition may fairly be said to be representative of most of Africa today. A more developed community demands meat of high quality from young and properly finished animals, and this is the I'equirement of the European and emergent African communities, a steadily rising demand which must be met from within the Continent if possible.
The early weaning of lambs
Authors: Brown T.H.
Published: March 2009

1. The literature on the early weaning of lambs has been reviewed.

2. Four experiments were carried out at the Grassland Research Institute, Hurley, during 1959, 1960 and 1961 on the early weaning of Suffolk x Half-Bred lambs. The technique used involved weaning one of a pair of twin lambs at ages varying from 15 to 28 days.

3. In 1959 oneof each of apair of six twin lambs was weaned on to grass alone at 15–20 days. No losses occurred, but the weaned lambs grew very slowly. The unweaned twin lambs remaining with the ewes (i.e. reared as singles) grew at rates comparable to those of single lambs.
Male sterility in field beans (Vicia faba L.). I. A male-sterile bean inherited as a Mendelian recessive
Authors: Bond D. A. , Drayner Jean M. , Fyfe J. L. , Toynbee-Clarke Gillian
Published: March 2009

1. A male-sterile winter bean, inherited as a simple Mendelian recessive, is described.

2. The sterility gene was shown to be expressed in the cytoplasm of eleven inbred lines of English winter beans, two varieties of English spring beans, six varieties of foreign spring beans and three varieties of broad beans (Vicia faba major). It is concluded that these varieties are unlikely to provide a fertility-inducing cytoplasm which would allow the development of a non-restoring pollinator.

3. Evidence of linkage between three chlorophyll-deficient mutants and the male sterility locus is given and circumstances are outlined by which a suitable marker gene could be employed to assist in large-scale production of hybrid seed.
Ruminal ammonia formation in relation to the utilization of groundnut meal and herring meal as protein sources for milk production
Authors: Chalmers Margaret I. , Marshall S. B. M.
Published: March 2009

1. Groundnut meal and herring meal have been compared as protein sources for ruminants.

2. Herring meal caused less extensive formation of ammonia in the rumen than did groundnut meal.

3. Nitrogen-balance experiments showed that herring meal fed to lactating goats was used more efficiently than groundnut meal fed under the same dietary conditions.

4. Herring meal was superior to groundnut meal for milk production in dairy cows.
Interactive effects of agronomic variables on marketable yield of leeks
Authors: Salter P. J. , Akehurst Jayne M. , Morris G. E. L.
Published: March 2009

Two experiments were carried out to study the effects of five agronomic variables on the marketable yield of transplanted leeks. In the first experiment two cultivars were used, cvs Splendid and Winterreuzen, and the treatments compared three plantraising systems, two ages of transplant when planted, and two plant population densities, two row spacings and two levels of nitrogen nutrition in the field. In this experiment some treatment interactions were confounded with each other.

In the later experiment only cv. Splendid was grown. There were two plant-raising systems, two plant-raising temperatures, two plant-raising nutrition levels, two times of transplanting (63 or 84 days from sowing) and four different sowings (7 and 28 February, 20 March and 10 April 1984). The duration of the growth period in the field was standardized by harvesting each treatment combination on two occasions, 168 and 189 days after transplanting.

The results from the first experiment showed that plants raised in modules at high temperature, planted early at a high plant density with higher than normal levels of nitrogen gave high marketable (> 12·5 mm in diameter) yields of 7·31 kg/m2, greater than that from any other treatment combination. The second experiment confirmed these general trends but also showed that the date of transplanting was of critical importance with the earliest plantings in the year giving the highest yields and with later plantings resulting in progressively lower yields irrespective of the way in which the transplants were raised. Comparisons with meteorological data showed that decreasing yields were associated with decreasing values of accumulated solar radiation and accumulated day-degrees during field growth.

These results are discussed in relation to other published data. They do not support some of the current recommendations for growing the crop but suggest that much more work needs to be done on production systems for this crop because of the potential for increasing marketable yields.
Evaluation of the nutritive value of single-cell protein (Pruteen) for lactating dairy cows
Authors: Teller E. , Godeau J.-M.
Published: March 2009

Two experiments were conducted with four lactating cows in a latin-square design. The rations were composed mainly of maize silage plus concentrates, supplemented with urea, Pruteen, or soya-bean meal supplying 25% of total dietary N. Nitrogen and energy balances were measured, and milk production recorded.

Dry-matter digestibility, intake of metabolizable energy (ME) and ME concentration in dietary dry matter were not significantly altered when Pruteen was substituted for soya-bean meal. However, mean nitrogen digestibility for all the treatments was significantly lower than expected from published relationships.

The substitution of Pruteen for soya-bean meal did not significantly affect the nitrogen balance of the animals or milk production, but the latter tended to be higher than that recorded with urea.

The responses to the different N supplements are discussed in relation to the feeding systems of the Agricultural Research Council and the French Protéines Digestibles dans l'lntestin Grêle, and are compared with predictions made from statistical relationships developed in our laboratory.
The effect of food intake and dietary fatty acids on the activity of stearoyl-CoA Δ9desaturase in pig adipose tissue
Authors: Buller K. J. , Enser M.
Published: March 2009

Stearoyl-CoA desaturase activity was determined in the subcutaneous and perirenal adipose tissue of pigs either fedad libitum, or starved for up to 48 h. The effect of saturated fatty acids, as suet, or linoleic acid, as corn oil, on the enzyme activity was determined in pigs refed after starvation or fed 50% of thead libitumintake.

Desaturase activity was similar in the outer and inner backfat and was twice as high as in perirenal adipose tissue. Starvation for 48 h decreased the activity by 70, 91 and 94 % in the outer and inner backfat and perirenal adipose tissue respectively. Lowering food intake to 50 % of normal decreased desaturase activity by 46% in the outer back-fat. There was no significant difference in the response of desaturase to 10% corn oil or suet added to the diet during refeeding after starvation or to the diet of underfed pigs. Although the enzyme thus appeared insensitive to dietary saturated fatty acids or linoleic acid, it was inhibited by linoleoyl-CoAin vitro.
The comparative yields of two types of leucaena (Peruvian v. Hawaiian) grown for forage production in Ryukyu Islands
Authors: Kitamura Y.
Published: March 2009

Leucaena leucocephala (Lam.) de Wit, a leguminous shrub, has come into use as a fodder plant for animals in the Ryukyu Islands as it provides highly palatable, high quality feed (Kitamura, 1985). It is superior to other feeds available in this regard (Higashiohmine, Aramoto & Yamashiro, 1971; Isa et al. 1982).
Selection of the components of a synthetic variety of Andropogon gayanus
Authors: Grof B.
Published: March 2009

Andropogon gayanus Kunth var. bisquamulatus Hack, is a polymorphic bunch grass, widely distributed throughout most of the tropical and subtropical savannahs of Africa, south of the Sahara in areas with a long dry season. This grass was introduced into the Colombian Llanos from the Shika Agricultural Research Station, northern Nigeria, in 1974. Subsequent to its introduction, a series of agronomic trials were initiated by Centro Internacional de Agricultura Tropical (CIAT) at the Carimagua Research Centre and various national research institutions in Latin America to evaluate the potential of A. gayanus, primarily in the vast Ultisol and Oxisol savannah regions of the continent. As a result of further evaluation at a number of locations, accession A. gayanus var. bisquamulatus CIAT 621 was released in 1980 in Brazil as cv. Flanaltina and in Colombia as cv. Carimagua 1. During 1982–3 Peru, Venezuela and Panama subsequently released the same accession under the cultivar names of San Martin, Sabanero and Veranero, respectively. It is estimated that 168000 ha have been sown with A. gayanus in Brazil since 1982 (J. E. Ferguson, C. Sere and R. de Andrade, personal communication). Smaller areas have been established in other countries.
The response to inoculation of the three chromosome races of Trifolium ambiguum sown with and without a companion grass. I. The effect of inoculation on yield of clover and grass
Authors: Evans Alice M. , Jones D. Gareth
Published: March 2009

Evidence is provided that T. ambiguum, in common with other legumes, responds to inoculation with an effective strain of Rhizobium both in the field and in the glasshouse. There were consistent differences between the responses of 2x, 4x; and 6x: chromosome races to inoculation. Grass plants grown alongside effectively nodulated T. ambiguum plants gave significantly higher yields than those grown with ineffectively nodulated plants. The higher percentage germination associated with inoculation may be due to an effect of the skim milk used as inoculum carrier.

We wish to thank Professor P. T. Thomas and Mr W. Ellis Davies of the Welsh Plant Breeding Station, for their interest and advice, and Professor A. H. Bunting, of Reading University, for reading and correcting the manuscript.
The effects on growth, development and yield of sugar beet of extension of the growth period by transplantation
Authors: Scott R. K. , Bremner P. M.
Published: March 2009

1. A series of three field experiments, concerning the effects on growth, development and yield of sugar beet of extension of the growing season by transplantation, were carried out in 1962, 1963 and 1964. The first two experiments were subject to sequential sampling programmes for growthanalysis purposes, but in the third only yield data were recorded.

2. Root yield increased with advance in planting date and increase in plant population in all 3 years. Nitrogen had no effect on root yield in any year. There was no consistent interaction between time of planting and plant population in their effects on root yield. The advantage for transplanting over field sowing ranged from 4 tons washed beet per acre in the case of an early field sowing (20 March) to 10 tons in a late one (23 April). There were no treatment effects on the concentration of sugar in the roots. The roots of transplants were more globular in shape and fanged than were those of field-sown beet.
Estimation of the carcass composition of different cattle breeds and crosses from fatness measurements and visual assessments
Authors: Kempster A. J. , Chadwick J. P. , Charles D. D.
Published: March 2009

Carcass data for 1053 steers from the Meat and Livestock Commission's beef breed evaluation programme were used to examine the relative precision of alternative fatness assessments for predicting carcass lean percentage. The data were from four trials and comprised both dairy-bred and suckler-bred cattle by a wide range of sire breeds.

A visual assessment of carcass subcutaneous fat content to the nearest percentage unit (SFe) was the single most precise predictor both overall (residual S.d. = 2·28) and within breed (residual S.d. = 2·05). Precision was improved by the addition in multiple regression of the percentage perinephric and retroperitoneal fat (KKCF) in carcass, a visual score of the degree of marbling in the m. longissimus and selected fat thickness measurements taken by calipers on cut surfaces (residual S.d. = 2·11 (overall) and 1·90 (within breed)).

When the best overall equation was applied to the breed means, there was substantial bias (predicted – actual carcass lean percentage). Biases ranged from +2·5 (purebred Canadian Holstein and Luing) to – 1·3 (Limousin crosses).

Breeds differed significantly in carcass lean content when compared at equal levels of fatness measurements. The differences depended both on the precision with which the measurements predicted carcass lean content and the observed differences in carcass composition that existed before adjustments to equal fatness were made.

The robustness of prediction equations was examined by applying them to independent sets of data (a total of 334 carcasses) from four other trials involving steers, heifers, cows and young bulls. Equations were stable for cattle of the same breed, sex and similar levels of fatness but important bias was found between more extreme types of cattle.
Phosphorus requirements of ewes in pregnancy and lactation
Authors: Braithwaite G. D.
Published: March 2009

The adequacy of the Agricultural Research Council (1980) recommendations for phosphorus for pregnancy and lactation has been investigated in ewes given a plentiful supply of dietary calcium.

The efficiency of absorption of P remained high and fairly constant throughout the whole experimental period and the rate of P absorption varied in direct relation to the P intake.

The endogenous faecal loss of P also varied with P intake and at all stages of pregnancy and lactation was higher than the value assumed by the Agricultural Research Council (1980) in their calculations of P requirements.

Bone mineral stores of Ca and P were lost in the normal way during late pregnancy and early lactation but were not replaced, as normal, in mid- to late lactation. At the end of the lactation, ewes were still in deficit of 125 g P and 100 g Ca.

It is argued that the Agricultural Research Council (1980) recommendations for P, particularly in mid- to late lactation, are too low and it is recommended that future calculations of requirements for pregnancy and lactation allow for the inevitable loss and subsequent replacement of skeletal mineral stores and also for the increased endogenous faecal losses of P that appear inevitable at the high P intakes needed to meet the increased demands.
Variation in tannin content in Vicia faba L.
Authors: Cabrera A. , Martin A.
Published: March 2009

The tannin content of milled seed of 55 lines of Vicia faba was evaluated and related to flower and testa colour, seed weight and percentage of testa. Tannin content in the lines analysed was related more to flower colour than to testa colour. No relationship existed between tannin content and seed weight. Lines with low tannin content had a low proportion of testa.
Chemotaxis of salt-tolerant and sensitiveRhizobiumstrains to root exudates of lentil (LensculinarisL.) genotypes and symbiotic N-fixation, proline content and grain yield in saline calcareous soil
Authors: Rai R.
Published: March 2009

TwoRhizobiumstrains and five lentil genotypes were most salt-tolerant under various salt stress conditions and strain LC 6 was the most sensitive. Salt-tolerant strains were more antibiotic-resistant and showed higher relative rates of oxidation of carbohydrates and tricarboxilic acid intermediates. The content and concentrations of root exudates of lentil genotypes were different and found to be attractants for theRhizobiumstrains. Under salt stress, significant interactions between salt-tolerant strains and genotypes resulted in different responses of nodulation and host plant growth measurements.
The effect of chlorite delignification on digestibility of some grass forages and on intake and rumen microbial activity in sheep fed barley straw
Authors: Ford C. W. , Elliott R. , Maynard P. J.
Published: March 2009

Sodium chlorite increased the degradability of fibre from a range of mature grass forages inoluding barley straw by 40–50 digestibility units when comparisons were made using ground (1 mm sieve) material incubated eitherin vitrowith cellulase or in nylon bags in the rumen. However, when fed to sheep, chlorite-treated barley straw was digested to a similar degree to untreated straw (49 and 57% respectively), but intake was significantly reduced (385 and 790 g/day respectively). The poorin vivoutilization of chlorite-treated straw coincided with high proportions of propionic to acetic acid in the rumen (0·85, cf. 0·28 with untreated feed) and absence of rumen fungi. Rumen pH and ammonia concentrations were not significantly different between diets. When incubated in nylon bags in the rumen of animals fed the corresponding diet, both untreated and treated straw (< 1 mm) were well colonized with micro-organisms, as measured by cystine accumulation which showed peaks on the fibres after 24 and 72 h. While large numbers of fungal sporangia were observed after 24 h incubation on digesta from untreated forage, no fungi could be detected on the chlorite-treated material. Cystine accumulation on the untreated straw after 72 h was not associated with a secondary growth of fungi.

Although barley straw chaff, ground (< 1 mm) after treatment with chlorite, was highly degraded in nylon bags in the rumen and with cellulasein vitro, larger particles (1 cm) suspended in nylon bags in an animal fed chlorite-treated straw actually gained weight, probably due in part to the degree of microbial colonization.
Effects of low sodium intake on magnesium metabolism of sheep
Authors: Martens H. , Kubel O. W. , Gäbel G. , Honig H.
Published: March 2009

Three sheep, equipped with cannulae in the dorsal rumen sac, abomasum and ileum, were fed a low sodium diet of artifically dried young grass. Mean daily intake of sodium was 310 mg. The sheep were given daily supplements of 0 or 2·3 g sodium by an intraruminal infusion.

The concentration of K in mixed saliva and ruminal fluid from the sheep not given sodium supplements increased and the concentration of Na decreased markedly. The changes in the ion concentrations were associated with an increase of the transmural potential difference across the ruminal epithelium.

The altered ion concentrations of Na and K in the ruminal fluid and the increased potential difference were accompanied by a decrease in Mg absorption from the forestomachs. The apparent availability of Mg from the gastrointestinal tract decreased from 34·5 (sodium supplementation) to 22·3 (low sodium intake).

It is suggested that a daily intake of Na of 310 mg did not cover the sodium requirement of these sheep and that a low sodium intake influences the absorption of Mg in a similar manner as it has been observed with a high K intake.

The results are discussed in context of grass tetany in ruminants. It is suggested that an inadequate intake of sodium is an overlooked factor of the pathogenesis of this disease.
The production and management of Stylosanthes gracilis at Shika, Nigeria:I. In sown pastures
Authors: Haggar R. J.
Published: March 2009

The contribution of the legume Stylosanthes gracilis to the nitrogen economy of mixed swards was assessed under both cutting and grazing conditions. In a cutting experiment, carried out during two wet seasons, a S. gracilis/Chloris gayana sward gave the same yields of dry matter and crude protein as a C gayana sward receiving 75 lb N and 167 lb N/acre (84 kg, 187 kg/ha) respectively. Lower yields were obtained from mixed swards containing Centrosema pubescens and Desmodium scorpiurus.

In a grazing experiment the mean live-weight production from a S. gracilis/Digitariasmutsii sward was equivalent to that produced from a pure grass sward receiving only 13 lb N per acre (5·9 kg/ha), although greater beneficial effects of the legume were apparent under high stocking conditions. In both experiments the legume tended to become dominant after 2 years.

Herbage yields from a S. gracilis/C. gayana pasture were significantly increased by phosphorus and sulphur; S. gracilis was particularly responsive to these elements. Under lenient defoliation, nitrogen reduced the proportion of the legume in the mixed sward, although frequent defoliation reduced the harmful effect of the nitrogen.

The results are compared with other published data and are discussed in terms of ways in which the grass/legume balance can be altered by different management practices.
The voluntary intake of silage by sheep:II. The effects of acetate on silage intake
Authors: Hutchinson K. J. , Wilkins R. J.
Published: March 2009

A perennial ryegrass silage was treated to give a range of acetic acid contents (2·0–8·8); pH and moistvire levels were held constant by adding solutions of the acid and of potassium hydroxide. When fed to sheep, ad libitum, the pattern of eating during the day was affected by acetate content in the silage but the intake over 24 h was unaffected. In a second experiment the infusion of acetic acid into the rumen depressed silage intake but this effect was not observed when part of the infusate was replaced by potassium acetate. It is considered unlikely that high acetate level per se will result in a low intake of silage.
The effect of sex on growth and carcass quality in the bacon pig
Authors: Blair R. , English P. R.
Published: March 2009

Castration of males is a long-established practice in animal husbandry, and although the use of boars rather than hogs was advocated by Fitzherbert in 1534 the use of castrates in pig production has continued to the present day.
The effect of the plane of nutrition on the shape of the ribs in lambs
Authors: Pálsson H. , Vergés Juan B.
Published: March 2009

1. The effect of four different planes of nutrition of lambs until they reach 30 1b. dressed carcass weight on the development of the form of the ribs is studied.

2. The growth in length of the ribs is found to be more influenced by age and less by the plane of nutrition than their growth in thickness, and is not reflected in the weight of the ribs.
A study of the effects of diet composition, within the bounds of normal diversity, on the characteristics of backfat lipid in pigs
Authors: Pearce J. , Walker N.
Published: March 2009

The experiment described was carried out to compare the effects of some combinations of dietary ingredients which were within the bounds of current commercial use but which differed in their lipid characteristics.

The four dietary treatments used were either low or high in lipid content with a high or low proportion of unsaturated fatty acids in that lipid. Fourteen pigs (seven gilts and seven barrows) were assigned at random to each dietary treatment. The major dietary constituents were barley × wheat × dried skim milk (treatment 1), barley × wheat × soyabean meal (treatment 2), barley + wheat + dried skim milk × tallow (treatment 3) and barley × wheat × maize × fish meal (treatment 4).

Production performances were satisfactory on treatments 1, 3 and 4. The pigs on treatment 2 ate less food, grew more slowly, had poorer feed conversion ratios and fatter carcasses than the animals on the other treatments; the reason for the poor performance on this diet is not clear.

Comparison of the fatty acid compositions of the backfat triglycerides and the dietary lipid shows that the dietary lipid had little effect on the backfat lipid characteristics; only in the case of linoleic acid was there a dietary-induced effect on the amount of this fatty acid in the backfat triglycerides of pigs on treatment 4.

Treatment 4 which produced the backfat with the greatest linoleic acid content also produced the softest backfat. The subjective fat scores of the carcasses of pigs fed the other diets were not related to the fatty acid compositions of the backfat triglycerides or the monoene/saturated fatty acid ratio.

These results are discussed in relation to the effects of diet and triglyceride structure on pig backfat lipid characteristics.
The effect of a reduction in food intake during late pregnancy on nitrogen metabolism in ewes
Authors: Guada J. A. , Robinson J. J. , Fraser C.
Published: March 2009

Twelve Finnish Landrace × Dorset Horn ewes with a mean litter size of 1·92 and a mean body weight of 75±3 kg were individually penned from 80 days of gestation to parturition and offered a diet with a metabolizable energy (ME) and crude protein content in the dry matter of 9·7 MJ/kg and 11·4% respectively. At 120 days of gestation daily ME intake was abruptly reduced from a mean of 0·48 to 0·25 MJ/kg W0·75for a period of 10 days.

The observed increase in the plasma concentration of urea due to the reduction in food intake was better correlated with lamb birth weight (r= 0·87) than was the increase in plasma free fatty acid concentration (r= 0·53) or the decrease in plasma glucose concentration (r= 0·76). Mean daily nitrogen balance decreased from a mean of 5·6 g before food restriction to – 1·8 g after food restriction. Although the effect was not significant, single bearing ewes excreted more total and urea nitrogen in the urine than multiple bearing ewes before food restriction. During food restriction the trend was reversed. The change in urea nitrogen excretion (Y, g/day) that resulted from the reduction in food intake was correlated (r= 0·73,P< 0·01) with lamb birth weight (X, kg); the relationship wasY= 0·54(±0·16)X – 3·48. It was estimated that the daily loss of nitrogen from the maternal body during the period of food restriction was approximately 80% of published values for the urinary nitrogen excretion of fasting non-pregnant sheep.
Comparison of chinoli (Brassica campestris subsp. oleifera × subsp. chinensis) and B. napus oilseed rape using different growth regulators, plant population densities and irrigation treatments
Authors: Rao M. S. S. , Mendham N. J.
Published: March 2009

Experiments were carried out between 1983 and 1987 in a cool but dry environment in Tasmania to evaluate the growth, development and yield of chinoli compared with the Brassica napus cultivar, Marnoo. In 1983/84 chinoli plants became large, with many pods, but then lodged at the stage of peak pod development. Seed yields were less than half those of the B. napus lines and only slightly better than that of B. campestris, ‘Jumbuck’. In subsequent experiments, lodging was either delayed or completely eliminated, either by the application of plant growth regulators, particularly PP333, or by using low populations or late sowing. However, these remedial measures were all associated with lower seed yields. Early flowering before the achievement of adequate plant size and then the setting of a large number of pods resulting in few seeds in each were identified as the main reasons for the low seed yields in chinoli. Irrigation after anthesis increased numbers of seeds/pod and thus gave better seed yields, but still not as high as those of Marnoo.
Soil–plant–water relations of oilseed rape (Brassica napus and B. campestris)
Authors: Rao M. S. S. , Mendham N. J.
Published: March 2009

Chinoli (Brassica campestris subsp. oleifera × subsp. chinensis), Marnoo and Apetalous (B. napus), with contrasting morphological characters, were compared over four seasons in Tasmania in 1985/86 and 1986/87. The total water use estimated from a depth of 70 cm increased in proportion to irrigations. Before irrigation all the crops had a similar pattern of moisture extraction but differences between the lines, and due to irrigations, emerged after the irrigation treatments. The genotypic differences were clearer in the winter sowing of 1986/87, when the growing season was longer. Apetalous, when unirrigated, extracted a greater amount of water from the lower, wetter regions of the soil profile, particularly in the longer winter sowing when its water use was the same as in the treatment receiving one irrigation. With consistently higher stomatal conductance, Apetalous used more water than chinoli or Marnoo. It also maintained a higher turgor at lower osmotic potentials, suggesting a greater degree of drought tolerance than found in the short duration chinoli which, although it had a lower water use, also gave lower seed yields.
Some aspects of pollination of oil-seed rape (Brassica napus L.)
Authors: Eisikowitch D.
Published: March 2009

The self-fertile cultivar of swede rape (Brassica napus) Maris Haplona does not usually autopollinate. The entomophilie pollen grains cannot be transferred by wind alone; anthers when flicked by insects or artificially under dry conditions behave like catapults raising a cloud of pollen grains.

Variability in the concentration of sugar in its two types of nectaries (within a single flower) may increase the range of visiting insects. All visiting insects, including honey bees, carried out pollination; it is suggested that beehives should be placed in fields of oil-seed rape in order to increase pollination.
Studies on the effects of foliar spray of nutrients on the performance of cow peas (Vigna unguiculata (L.) Walp.)
Authors: Tayo T. O.
Published: March 2009

In three field trials, three varieties of cow pea (Prima, Ife Brown and Vita-5) grown as mono-crops or interplanted with maize (in one trial) were sprayed with a combination of PKS or NPKS in solutions containing 100, 100, 100 and 41 mg/1 of N, P, K and S respectively at the onset of flowering or 2 weeks later, in order to evaluate the effect of foliar spray of mineral nutrients on the performance of the crop.

Early season sprayings of NPKS and PKS increased vegetative development and dry-matter accumulation in both mono- and mixed-croppings of Prima and Vita-5, but had little effect on Ife Brown. Seed yield was increased by 80–225 kg/ha in Prima and 160–218 kg/ha in Vita-5. In all cases of enhanced growth and yield, spraying at flowering was more beneficial than spraying 2 weeks later whilst NPKS evoked greater responses than PKS.

In two late-season trials, all treatment combinations enhanced vegetative development and dry-matter accumulation in Ife Brown and Vita-5. Seed yield of Ife Brown was increased by 206 kg/ha in the first late season and by 550 kg/ha in the second late season whilst that of Vita-5 was increased by 226 kg/ha in the first late season, during which it was planted. In the first late season of Ife Brown, late spraying was more beneficial than early spraying, whilst plants sprayed with PKS out-yielded those sprayed with NPKS. On the other hand, in the second late season, Ife Brown responded more to early spraying than late spraying and NPKS was more beneficial than PKS: Vita-5 grown in the first late season responded similarly.

In all cases of enhanced seed yield during the seasons, the pathway of response was through increased pod production and/or retention on the plants. The results therefore suggest that foliar spray of nutrients during the post-flowering period enhance seed yield in cow pea by ensuring prompt delivery of mineral nutrients to the site of photosynthesis at a time when nutrient depletion in the leaves and reduced efficiency of mineral nutrient uptake by the roots limit the supply of photosynthates to developing reproductive organs.
Effect of air temperature and feed intake on live weight and water balance in sheep
Authors: Degen A. A. , Young B. A.
Published: March 2009

Environmental conditions (Clark & Quin, 1949; Daws & Squires, 1974; Degen & Young, 1980) and total feed intake (Clark & Quin, 1949; Forbes, 1968; Degen & Young, 1980) influence the water intake of sheep. In general, high temperatures increase the requirements for water needed for evaporative cooling and high feed intakes necessitate more water for excretion of waste products. This study was designed to measure water intake and estimate the partition of water output in sheep maintained at four air temperatures and offered four levels of a ration.
Effect of fertilizer placement and row arrangements on the yield of two varieties of wheat grown under dryland conditions
Authors: Singh R. K. , De R. , Turkhede B. B.
Published: March 2009

Experiments made under dryland conditions in the post-monsoon period for 3 years showed that deep placement of N and P fertilizers at 12 or 18 cm led to better utilization than their shallow placement at 6 cm. Grain yield was maximal when the fertilizer was placed at 18 cm depth. The yield increase by deep fertilizer placement resulted from higher tiller survival till harvest. In these treatments water use efficiency and mineralizable N content in soil were higher.

Of the two varieties tested the taller cultivar (C 306) yielded more in normal years but lodging due to a severe storm in one of the years reduced its yield considerably. While the yield of the tall variety was not much affected by variations in row distances, the dwarf (DL 153–2) responded to these variations and greatest yield was obtained at a row distance of 27·5 cm.
The use of dosed and herbage n-alkanes as markers for the determination of herbage intake
Authors: Mayes R. W. , Lamb C. S. , Colgrove Patricia M.
Published: March 2009

The recovery in the faeces of the n-alkanes of herbage (odd-chain, C27–C35) and of dosed artificial alkanes (even-chain, C28 and C32) was studied in twelve 4-month-old castrated male lambs. The lambs received three levels of cut, fresh perennial ryegrass or a mixed diet of perennial ryegrass (0·70) and a barley-based concentrate (0·30) (500–900 g D.M./day). C28 and C32 n-alkanes (130 mg each), absorbed onto shredded paper, were given once daily for 17 days to test whether the recoveries of herbage and dosed alkanes were similar to enable their use as markers for determining the herbage intake of grazing sheep. Stearic and palmitic acids (130 mg each) were given with the dosed alkanes to half of the animals with the objective of facilitating emulsification of the dosed alkanes within the digestive tract.

With the exception of C27 n-alkane, the faecal recoveries of all alkanes were unaffected by diet, feeding level or emulsifying agent. Faecal recovery of odd- chain herbage n-alkanes increased with increasing C-chain length. The recovery of the dosed C28 n-alkane was slightly greater than the recoveries of both C27, and C29 n-alkanes of herbage. The recoveries of the dosed C32 n-alkane and the herbage C33-alkane were the same.

The mean herbage intake estimated using C33 and C32 n-alkanes was identical to the actual herbage intake. Other alkane pairs gave slight underestimates of herbage intake ranging from 3·5% for the C28–C29 pair to 7·6% for the C27–C28 pair. No cyclical pattern of n-alkane excretion throughout the day was observed. Examination of daily variations in faecal alkane concentrations indicated that the start of alkane dosing should precede the sampling of faeces by at least 6 days.

These results suggest that accurate estimation of herbage intake in grazing sheep is possible from the simultaneous use of dosed C32 and herbage C33 n-alkanes as markers.

The method may be particularly useful in enabling unbiased estimates of herbage intake to be made in animals receiving supplementary feed.