bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of lasalocid and protein levels on feed intake and growth rate of Awassi lambs
Authors: Muwalla M. M. , Harb M. Y. , Crosby T. F.
Published: November 2021

Lasalocid is a polyether antibiotic derived from the fermentation of streptomyces lasaliensis used as a coccidiostat in sheep. There are varying literature reports on lamb growth rate and feed intake when lasalocid is included in the diet of feedlot lambs. While some reports have shown that lasalocid enhances feed efficiency in ruminants by decreasing feed intake and either maintaining or improving rate of gain others indicate that lasalocid did not have any effect on lamb growth rates or feed efficiency (Stobart et al., 1987). Also, when lasalocid was fed to Chios lambs, growth rate was increased but there was no improvement in feed conversion efficiency (Hadjipanayiotou et al., 1988). There are no published data in the literature relating to the use of lasalocid as a growth promoter in the Awassi breed of sheep fed complete diets and the purpose of this study was to investigate the effect of lasalocid with two levels of protein on the growth rate and feed efficiency of weaned male and female Awassi lambs.
Predicting the nutritive value of tree fodder: consistency and complementarity between assessments made by Nepalese, smallholder farmers and by laboratory techniques
Authors: Thorne P.J. , Walker D.H. , Subba D.B. , Wood C.D. , Sinclair F.L. , Thapa B.L.
Published: November 2021

Tree fodder is a vital dry season feed resource, used to supplement crop residues, on smallholdings in Nepal and other parts of the Himalaya. Farmers have a detailed and effective knowledge of the nutritive value of different types of tree fodder and the factors affecting this (Rusten and Gold, 1991; Thapa et al, in review). However, the implications of this knowledge for planning research to develop fodder resources and feeding strategies or for the effective delivery of research results to farmers are unclear. The study described here assessed the consistency between analytical indicators and farmers' perceptions of the nutritive value of tree fodder. The potential for using information from these two sources, in a complementary manner, to improve the focus of nutritive value assessment on farmers' needs was also examined.
The interactive effects of monensin treatment and diet composition on in vitro semi-continuous rumen fermentation using Rusitec
Authors: Mackintosh E.D. , Phipps R.H. , Sutton J.D. , Wilkinson J.
Published: November 2021

Rusitec has become the method of choice when studying the in vitro ruminal effects of the gram-positive ionophore monensin. The objective of the current study was to determine the in vitro effects of monensin treatment on volatile fatty acid (VFA) molar production and methane production from two complete diets which varied in maize silage:grass silage ratio and NaOH treated wheat grain:molassed sugar beet feed (MSBF) ratio.
The effectiveness of mixed-model smoothing for prediction of lactation yields
Authors: Woolliams J.A. , Waddington D.
Published: November 2021

The accurate prediction of lactation yield for a dairy cow has been a long standing goal for improving management. Historically the approach has been to assume that yield as a function of time follows a lactation curve which can be assigned a form that applies to all cows, and that cows differ in the parameters of this common curve. This has led to a plethora of forms being suggested for this common curve, of which perhaps the most well-known is that of Wood(1967). The biggest problem with this approach is the assumption that all cows and all management systems combine to produce individual lactations described by a single form of ‘lactation curve’. A novel approach using mixed-model smoothing was investigated in this study which: (i) fits a shape of lactation, assuming no specific parametric form , to daily yield records of a group of cows by using a patterned (co)variance matrix to describe deviations from a linear trend for time postpartum in a mixed model; and (ii) allows individual yields to be predicted using this ‘mean’ curve and the deviation of an individual's yield record from this mean.
The effect of asynchronous diets on the function of the rumen in the lactating dairy cow
Authors: Henderson A.R. , Garnsworthy P.C. , Newbold J.R. , Buttery P.J.
Published: November 2021

Sinclair et al. (1993) found that a diet formulated to be synchronous with regard to hourly release of nitrogen and energy increased microbial protein synthesis by 14% in sheep. Dairy cows in early lactation experience a shortfall of energy and protein, with available protein determining the overall efficiency of metabolism (MacRae and Lobley, 1986) and subsequent milk production. It is therefore necessary to maximise microbial protein yield during this period. In this study diets were designed for lactating dairy cows to contain the same feed ingredients, but to release nitrogen and energy in the rumen at different times. Rumen fermentation parameters, nutrient flows to the small intestine and production performance were investigated.
A comparison of performance and carcass composition of beef cattle finished on grass or concentrate diets
Authors: Lavery N.P. , Steen R.W.J.
Published: November 2021

It is now well established that finishing diets for beef cattle containing a high proportion of grass silage produce lower growth rates and a greater proportion of fat in the gain than high-concentrate diets offered at the same energy input. However, a major proportion of beef cattle in the British Isles are finished off grass and there is little information on the carcass composition of grass-finished cattle relative to those finished on high-concentrate diets. Two comparative slaughter experiments involving both steers and heifers have been carried out to compare grazed grass and concentrate diets in terms of performance and carcass composition at equal levels of performance.
Reducing the cost of beef production through the genetic improvement of net feed efficiency
Authors: Herd R.M. , Archer J.A. , Arthur P.F. , Richardson E.C.
Published: November 2021

Feed is the single largest cost in most animal production systems. Feed conversion ratio (FCR) is a commonly used measure of growth efficiency. Previous research has shown that FCR is moderately heritable and highly related to growth rate. While selection for FCR is beneficial to those feeding growing cattle for slaughter, any associated increase in the size of breeding females will mean this benefit will be at a cost to the calf breeder, as larger breeding cows require more feed.
The effect of extending the grazing season in early spring on dairy cow performance
Authors: Sayers H.J. , Mayne C.S.
Published: November 2021

Previous studies (Mayne and Laidlaw 1995) have shown that early turnout of dairy cows to spring pasture for a few hours per day (extended grazing) reduces silage intake and increases animal performance relative to that of animals retained indoors. The objective of the present study was to assess the effects of grazing severity and/or degree of silage restriction during the indoor feeding period on the response to extended grazing.
Dietary preference of dairy cows grazing grass and clover
Authors: Rutter S.M. , Orr R.J. , Penning P.D. , Yarrow N.H. , Champion R.A. , Atkinson L.D.
Published: November 2021

The development of grazing management strategies to optimise nutrient intake from grazed herbage requires an understanding of the factors influencing the dietary preference of grazing domestic ruminants. Although there has been considerable progress in understanding the factors influencing the dietary preference of grazing sheep, there has been comparatively little research with lactating dairy cows (Rutter et al., 1997). The aim of the experiment reported here was to study the dietary preference of lactating dairy cows grazing grass and clover.
Comparison of bovine rumen liquor and bovine faeces as sources of micro-organisms for the in vitro gas production technique for assessing silages of maize and maize plant fractions
Authors: Altaf U.R. , Mauricio R. , Mould F.L. , Smith T. , Owen E. , Phipps R.H. , Theodorou M.K.
Published: November 2021

A previous study (Mauricio et al., 1998) with 12 forage substrates (straw, hay and dried grasses) showed a high correlation between rumen liquor and faeces for total gas production and in vitro organic matter digestibility (OMD). However parameters estimated using faecal inoculum were generally lower man when using rumen liquor. To confirm this observation, a second study was conducted using maize silage and silages made from maize plant fractions.
Digestion and nitrogen retention in steers offered grass silages made with no additive, formic acid or bacterial inoculant, and supplemented with two levels of concentrates
Authors: Shiels P. , O'Kiely P. , Moloney A.P. , Caffrey P.
Published: November 2021

Beneficial effects of inoculants on the nutritive value of well-preserved grass silage for beef cattle have been described (Keady and Steen, 1994). Less information is available on the efficacy of inoculants when untreated grass is preserved badly. The first objective of this study was to determine the effect of one inoculant under such conditions. Since an improvement in nutritive value of silage may be hidden when supplementary concentrates are offered, the second objective of this study was to determine the interaction between silage additive treatment and concentrate supplementation on the nutritive value of the resulting diets.
Effect of concentrate diets and slaughter weight on the performance of weaned continental x stickler bulls
Authors: Fallon Richard J. , Drennan Michael J.
Published: November 2021

Due to the high growth potential of bulls compared cross steers and the reduced price of concentrate feeds, there is a gradual move towards feeding continental and bulls from the suckler herd on all concentrate diets from weaning to slaughter at 12 to 15 months of age. The objective of this study was to determine the effects of diet type and slaughter weight on animal growth and feed conversion efficiency.
Ruminal disappearance and intestinal digestibility of amino acids in intensively reared beef cattle
Authors: Vicente F. , Guada J.A. , Martín-Orúe S.M. , Castrillo C.
Published: November 2021

Manipulation of amino acids (AA) supply to the duodenum is constrained in ruminants by insufficient knowledge on the AA profile of undegradable protein. There is evidence that rumen degradability and intestinal digestibility of individual AA may differ from that of nitrogen (N) or total AA (TAA) (Erasmus et al., 1994, O'Mara et al., 1997) although differences in intestinal digestibility are probably of relevance only in roughage and overheated feeds (Van Straalen et al., 1997). The objective of this experiment was to provide more information about the relative influence of rumen degradation and intestinal digestion on the AA profile of the absorbed fraction of four protein sources commonly used in beef cattle rationing.
Organoleptic properties and fatty acid content of muscle from young lambs and hoggets fed grass diets
Authors: Enser M. , Kurt E. , Chiles A. , Nute G.R. , Wood J.D.
Published: November 2021

Sheep production under extensive conditions is environmentally friendly but on upland pastures animals may not reach slaughter weight within one season. However, meat from older ‘hoggets’ will have different organoleptic properties to that from ‘young’ lambs which may affect its acceptability. Whilst prolonged grazing could intensify the highly acceptable flavours associated with grass consumption, which result from a high dietary intake of α-linolenic acid, prolonged fattening can produce less acceptable muttony flavours. Meat quality differences between lambs and hoggets have been compared in this trial by examining 8- and 20- month old Herdwick sheep, produced on grass fells in Cumbria and reputed to produce high quality meat. Grass-fed Suffolk crosses aged 6 months have been used as a control.
Effects of supplementary feed and competition with Cambridge ewes on the browsing behaviour of Welsh Mountain sheep
Authors: AL-Shami Salah , Ap Dewi I. , Omed H.
Published: November 2021

Trees and shrubs play an important role in increasing feed supplies to animal production in many tropical systems. These feeds sources can be browsed directly by animals or can be cut and carried (Ivory, 1989). Understanding the behaviour of domestic animals is an important tool in improving their management and production (Malechek and Provenza, 1983). An experiment was conducted to examine the effect of between-breed competition on the browsing behaviour of Welsh Mountain sheep, with alternative sources of supplementary feed using Cambridge ewes as the competing breed.
Grainbeet as a feed for ewes in late pregnancy
Authors: Pattinson S. E. , Locke A. , Minter C. M.
Published: November 2021

Within early lambing systems, there is a heavy reliance on concentrate feeding in late pregnancy. Therefore, the possibility of replacing conventional dietary ingredients (e.g. barley, fishmeal) with cheaper by-products, such as sugar beet pulp and brewers grains, is of particular interest. Pelleted distillers barley grains fed with molassed sugar beet nuts have been shown to be a suitable feed for pregnant ewes (Merrell and Hyslop, 1994). However, some health problems have been noted when feeding malt distillers wet grains (Vipond and Lewis, 1993). The objective of this trial was to investigate the effect of feeding grainbeet (a mix of 5 parts brewers grains to 1 part molassed sugar beet pulp) on ewe performance, colostrum production and lamb performance.
A comparative study of fat and protein levels in the colostrum of prolific and non-prolific sheep
Authors: Anderson J.M.L. , Barclay M.N.I. , Harvey M. J. , Waterhouse A.
Published: November 2021

It is vital that lambs receive at least 50ml/kg body weight of colostrum as soon as possible after birth. Without this, the lamb will be deprived quickly of energy for thermoregulation, as well as antibody protection. Colostrum contains high levels of fats and lactose, proteins and vitamins; however the consistency and colour vary between individual animals. Little is known of the cause of these variations. This experiment aimed to examine whether there were breed, age, genotype and litter size differences in the fat and protein levels of ewe colostrum collected within one hour of parturition.
Effect of dietary unsaturated fats on the flavour, and on oxidative and colour stability, of Suffolk, Friesland and Soay sheep meats
Authors: Kurt E. , Nute G. , Enser M. , Richardson R.I. , Sinclair L.A. , Wilkinson R.G. , Wood J.D.
Published: November 2021

Nutritional recommendations to improve the human diet are to increase the P:S ratio and to decrease the n-6:n-3 ratio of food (Department of Health 1994). However, increasing the degree of unsaturation of meat lipids may alter the flavour of the cooked meat and can increase its susceptibility to oxidative changes such as lipid rancidity and colour deterioration. We have studied these quality aspects in meat from three breeds of lambs fed different fats.

Seventy two entire ram lambs of three genotypes were used in a 3x4 factorial design: Suffolk x Lleyn, Frieslands x Lleyn and Soay lambs were fed diets, for an average of 80 days, containing one of four fats at 50g/kg supplemented with 200 IU/kg vitamin E: 1, control, 2, linseed, 3, fish oil and 4, fish oil plus linseed (50:50). Sensory assessment was performed on loin chops grilled to an internal temperature of 74°C which were rated using 100mm unstructured line scales. For colour and lipid oxidation measurements, 10mm thick leg steaks were aged for 10 days in vacuum at 1°C then repacked in modified atmosphere (O2:CO2,75:25) and displayed under light at 4°C for 6 days.
Thermoregulation in wet Shetland ponies
Authors: Booth M.E. , Pearson R.A. , Cuddeford D.
Published: November 2021

Understanding the influence of the weather on the energy requirements of horses living outdoors during winter is essential when estimating feed requirements. Measurements of heat production from live horses have only been made at different air temperatures. The influences of other weather parameters, such as precipitation and wind speed, which are known to increase the rate of heat loss in other domestic stock, have not been researched for horses. The aim of this study was to measure the effect of wetting the upper body surface of Shetland ponies in winter coat on their rate of heat production (W/kg) and on their skin and body temperatures (°C ).

Two mature Shetland pony stallions (178 and 200 kg liveweight) in full winter coat (coat parameters over the back; mean depth 2.38 cm; mean length 3.25 cm; mean density 79.25 mg/cm2), and in good body condition (condition score 2; Pollock, 1980), were housed at ambient temperature (range 2 - 9.5 °C) in an open-sided shed and fed meadow hay at maintenance energy requirements (NRC, 1989).
The effect of an inoculant additive on the fermentation characteristics of grass silage and bovine performance
Authors: Johnson P.N. , Grundy H.F. , Stanway A.P.
Published: November 2021

The efficacy of inoculant silage additives has often been questioned under difficult ensiling conditions. This study was conducted under testing conditions to test the efficacy of an inoculant additive (SA55) on silage fermentation and animal performance.

A perennial ryegrass (Lolium perenne) based sward was mown and conditioned on 29 October 1996 and was picked up on 30 and 31 October. Two similar precision-chop forage harvesters were used, one picked up grass without applying additive (Control), whilst the second applied the inoculant additive (SA55). SA55 (Microferm Ltd) was applied at a target rate of 2 1/t to give 5 x 105 organisms (Lactobacillus plantarum, Paediococcus acidilactici, Lactococcus lactis lactis and clostridial bacteriophages) per gramme of grass. The harvesters picked up adjacent swaths and dedicated trailers serviced each harvester. Frequent checks were made on the application rate of the additive. Two similar, roofed bunker silos were loaded with grass, using loaders dedicated to each silo. Loads of grass were tipped in their respective silos to avoid Cross contamination during the filling operation. Care was taken to ensure equal consolidation of both clamps. After consolidation, clamps were sealed with polythene sheeting and weighted down with tyres. Each load of grass was weighed and sampled.
The in situ degradability of dry matter, neutral detergent fibre and starch in whole-crop wheat harvested at three stages of maturity
Authors: Moos T.C. , Sutton J.D.
Published: November 2021

The choice of optimal stage of maturity at harvest for whole-crop wheat remains controversial. Problems of aerobic stability with crops harvested and ensiled at an early stage led to increased interest in harvesting at a later stage and preserving the crop with urea. However recent studies have shown low starch and fibre digestibility with such crops when fed to lactating dairy cows (Sutton et al.,1991). The purpose of the present work was to determine the effect of harvesting wheat at three stages of maturity on the in situ degradability of dry matter (DM), neutral detergent fibre (NDF) and starch.
Influence of different sources of methionine (DL methionine, hydroxy-analogues of methionine) and sulphur on the digestibility of organic matter of maize silage measured in vitro
Authors: Robert J.C. , Ferragu V. , Bouza B. , Williams P.E.V.
Published: November 2021

Rode et al (1997) reported a significant improvement in milk production and milk fat content when the ration was supplemented at the start of lactation with hydroxy-analogue of methionine (HMB) (DL,2 hydroxy 4 (methyl thio) butanoic acid. This could be explained either by the fact that HMB in the liquid form, in a manner similar to the calcium salt of HMB is used by the rumen microorganisms, resulting in the stimulation of the rumen microflora or that the HMB supplies by-pass methionine analogue to the duodenum. The objective of the present trial was to measure the effects of HMB in the rumen using a rumen simulation technique and to test the effect of different sources of methionine on the digestibility of the organic matter of maize silage.

Experiments were carried out using the in vitro rumen technique (Menke et al, 1988) (HFT). Different sources of methionine were tested : two sources of the hydroxy-analogue of methionine (HMB) : [A] AlimetTM (88,2%) (Novus Int Inc) and [B] RhodimetTM AT88 (88,9%) (Rhone Poulenc Animal Nutrition), [C] calcium salt of HMB (85,3%) [D] Rhodimet NP99 (99%) (DL methionine powder (RPAN)) [E] mineral sulphur in the form of sodium sulphate (99,5%).
Effect of Nitrogen Source on Fermentation Characteristics of Citrus Pulp
Authors: Debersaques Filip M.A. , Williams Barbara A. , Tamminga Seerp
Published: November 2021

Rumen microorganisms have variable requirements for a nitrogen source. Cumulative gas production (Theodorou et al., 1994) is often measured using media containing both ammonia (NH3) and mixed peptides (trypticase-TRYPT) to ensure that all microbes will have sufficient nitrogen (N) of the appropriate quality for growth and metabolism. This experiment was conducted to assess the effect of N source in the medium on the fermentation characteristics of citrus pulp, which was used as being representative of a readily fermentable carbohydrate.
Oocytes from gilts of domestic pig (Sus scrofa domesticus) and wild boar (Sus scrofa) species exhibit similar developmental potential during in vitro maturation
Authors: Prathalingam N.S. , Rust K. , Staines M.E. , McCallum G.J. , Edwards S.A. , English P.R. , McEvoy T.G.
Published: November 2021

In vitro embryo production strategies have been considered as possible means to protect wild and endangered animal species through assisted breeding programmes. They also offer the possibility to preserve genetic material from such stock or to facilitate breeding in captivity. The relevant technologies, however, have been developed to meet the needs of oocytes and embryos of domesticated animals and their suitability for wild species remains largely unknown. This study investigated the ability of in vitro maturation procedures, designed for oocytes of domestic pigs (Sus scrofa domesticus), to support the development of oocytes from wild boar (Sus scrofa)gilts.
Uptake and depletion of β-carotene by bovine corpus luteum cells
Authors: Arikan S. , Rodway R. G.
Published: November 2021

β-Carotene is present in extremely high concentrations in the bovine corpus luteum. It may be necessary for optimal ovarian development and steroidogenesis. We have previously shown that treatment of bovine luteal cell cultures with a High Density Lipoprotein (HDL) preparation containing β-carotene can significantly increase progesterone production (Arikan and Rodway, 1997). The main objectives of the present study were; 1. To investigate uptake and depletion of β-carotene by luteal cells. 2. To examine whether LH or dibutyry1 cyclic AMP (dbcAMP) has an effect on the metabolism of β-carotene in luteal cells.
Short Term Intake Rate (STIR) as a method of ranking the intake potential of forage mixtures by dairy cows
Authors: Harrison S. , Romney D.L , Phipps R.H , Owen E.
Published: November 2021

Studies conducted by Moseley and Manendez (1989) and Gill and Romney (1994) have indicated a good correlation between potential intake rate and voluntary food intake for certain feedstuffs. Therefore development of a simple technique to assess intake rate could enable rapid assessment of feed acceptability. This experiment examined what will be termed Short Term Intake Rate (STIR) as a method of ranking forage mixtures in terms of intake potential.

Five individually fed multiparous Fresian Holstein dairy cows were offered five silage based diets ad libitum daily for five days in a latin square design. The diets consisted of grass silage (A), or grass silage and maize silage in a 1:3 DM ratio (B, C, D and E). The DM content of the grass silage (A) was 279 g DM/kg, and the target DM content of the maize silage used in diets B, C, D and E was 230, 280, 300 and 380 g DM/kg respectively. The DM content of the forage mixtures B, C, D and E were 278, 302, 318 and 373 g DM/kg.
The effect of distillery by-products and molassed sugar beet feed on feed intake and milk production of dairy cows fed a maize silage based total mixed ration
Authors: Phipps R. H. , Jones A. K. , Perrot J.G.
Published: November 2021

An earlier study conducted at the Centre for Dairy Research (Phipps et al. 1996) using a total mixed ration (TMR) based on maize silage, showed that when distillers grains wheat and molassed sugar beet feed (MSBF) replaced cereal and protein supplements, milk yield and dry matter (DM) intake were maintained but there was a large and significant reduction in milk fat and a small but significant reduction in milk protein. This depression in milk protein was attributed to the high oil content of distillers grains, which would have reduced fermentable metabolisable energy intake which in turn may have adversely affected microbial protein synthesis and reduced milk protein content. The aim of the current study was to devise a nutritional regime using distillers grains maize (DGM) and MSBF in a TMR which would allow milk fat content to be substantially reduced without compromising either DM intake, milk yield or milk protein content.
The effect of supplementary carbohydrate composition on lactational performance in dairy cows grazing alfalfa pasture
Authors: Castillo A.R. , Beever D.E , Gregoret R.F. , Onetti S.G. , Quaino O.R.
Published: November 2021

The rate of disimilation of the dietary protein fraction of fresh forages, especially fresh legumes, is rapid and often exceeds microbial requirements for ammonia [Beever, 1993]. Consequently total dietary nitrogen [N] utilisation is impaired due to increased absorption of ammonia from the rumen and excretion of urea via the kidneys. This experiment, as part of a larger co-ordinated study to examine N utilisation in alfalfa swards for milk production, considered the evaluation of different isoenergetic supplements formulated to contain contrasting carbohydrate components with respect to starch and fibre level and type, and water soluble carbohydrate content.

Forty multiparous Holstein cows in immediately post peak lactation were randomnly allocated to one of four alfalfa paddocks, and provided fresh daily allowances [13kg Dry matter (DM)/cow/d] by means of electric fencing. Cows were milked twice daily [0600&1500h] when 3.5kg DM concentrate was offered at each milking. At all other times cows were at pasture and intakes were estimated by measuring pasture DM on offer to and refused by the cows.
Effect of dry period treatment on endocrine profiles of Holstein-Friesian dairy cows
Authors: Moorby J.M. , Beck N.F.G. , Dhanoa M.S. , Davies D.W.R. , Fisher W.J.
Published: November 2021

The dry period nutrition of the dairy cow can significantly affect subsequent milk production. It has been suggested that part of this effect can be attributed to the animal's use of labile body protein in support of early lactation nutrient requirements. If this is so, then there may be endocrine changes to signal nutrient partitioning. This experiment was designed to investigate the effect of offering diets differing in protein content during the dry period on changes in the endocrine profiles of animals over that period and during the first 21 weeks of lactation.

Forty-eight multiparous Holstein-Friesian cows were offered one of three different dry period diets for 6 weeks before predicted calving (16 animals per treatment): A) grass silage only, B) a grass silagetoarley straw mix (60:40 on a dry matter basis), or C) grass silage plus 0.5 kg/d high protein maize gluten meal. Diets A, B and C differed in the amounts of protein supplied: medium, low and high respectively. After calving, all animals were offered the same diet of ad libitum grass silage and concentrates at a stepped fixed rate.
The use of a soluble glass zinc, cobalt and selenium bolus to correct zinc deficiency in sheep
Authors: Kendall N.R. , Telfer S.B.
Published: November 2021

Sub clinical zinc deficiency has been suggested to be involved in disease conditions such as broken mouth periodontitis, footrot and mastitis. However, although there is little risk of primary deficiency in the UK. there are large areas around the Mediterranean. Northern Africa and North America that are reported to be deficient in zinc. Therefore a method that could deleiver a long term continuous supply of zinc would be beneficial in these situations. This trial was designed to examine zinc availability from a zinc, cobalt and selenium soluble glass bolus administered to zinc deficient lambs fed on a low zinc diet throughout the trial.
An examination of the effects of level of fish oil inclusion in the diet on rumen fermentation parameters in cattle
Authors: Mayne C.S. , Keady T.W.J. , McConaghy D A
Published: November 2021

The current milk quota regime within the European Community restricts both the volume and butterfat content of milk supplies from farms. Reduction in the butterfat concentration of milk enables an increase in liquid milk supplies, provided that the national butterfat base has been exceeded. In a concurrent study (Keady and Mayne, 1998) inclusion of fish oil in the diet of lactating dairy cows depressed butterfat content by up to 15 g/kg, consequently increasing the volume of milk which may be supplied in a quota situation by 0.27. The aim of the present study was to examine if the effects of fish oil inclusion on milk fat content were mediated via changes in rumen fermentation parameters.
Mapping the Thermal Structure of Southern Africa From Curie Depth Estimates Based on Wavelet Analysis of Magnetic Data With Uncertainties
Authors: Sobh M. , Gerhards C. , Fadel I. , Götze H.‐J.
Published: November 2021

Surface heat flow provides essential information on the thermal state and thickness of the lithosphere. Southern Africa is a mosaic of the best‐preserved and exposed crustal blocks, assembled in the early late Archean and then modified by a series of major tectono‐thermal events, both of Precambrian and Phanerozoic. Understanding the thermal and compositional structure of the southern African lithosphere provides crucial information for the actual causes, processes of lithospheric stability, and modification. Curie depth, interpreted as the depth to 580°C, provides a valuable constraint on the thermal structure of the lithosphere. Due to the sparse distribution of surface heat flow data, we examine the degree to which the thermal structure of the crust can be constrained from Curie depth estimates in southern Africa. We provide a Curie depth map for southern Africa (obtained from the inversion of magnetic anomaly data via power spectral methods and wavelet analysis) alongside with a heat flow map (based on the previous Curie depth estimates), both equipped with uncertainties via a Bayesian approach. Opposed to other cratonic regions, the observation of a shallow Curie depths and low heat flow over the Kaapvaal Craton suggests a thermochemical reworking of the cratonic lithosphere in this region. Furthermore, a comparison with a model for the Moho depth reveals significant variations of the Curie depth, which may be located below or above the Moho in large regions. Both observations indicate that in certain regions magnetic anomaly based Curie depth estimates may reflect a compositional rather than a temperature controlled constraint.
Observation of High‐Frequency Electrostatic Waves in the Dip Region Ahead of Dipolarization Front
Authors: Wei Y. Y. , Huang S. Y. , Yuan Z. G. , Deng X. H. , Jiang K. , Xu S. B. , Zhang J. , Zhang Z. H. , Xiong Q. Y. , Yu L. , Lin R. T.
Published: November 2021

Dipolarization front (DF) is a sharp magnetic structure featuring the increase of Bz in the magnetotail. Various types of waves have been observed around the DF. However, in the magnetic dip ahead of the DF, very few waves have been reported so far. In this study, we report broadband high‐frequency electrostatic waves in the dip region by using high resolution data from the magnetospheric multiscale (MMS) mission. The frequency range of these electrostatic emissions is higher than electron cyclotron frequency but lower than electron plasma frequency. These high‐frequency waves are quasi‐parallel propagating, and their parallel components dominate. Simultaneously, the measured field‐aligned electron distribution function (EDF) has a positive slope (df/dv|| > 0). The kinetic theory dispersion relationship curve based on the measured EDF reveals that the positive slope is responsible for the generation of high‐frequency electrostatic wave in the magnetic dip ahead of the DF.
Multi‐Event Studies of Sudden Energetic Electron Enhancements in the Inner Magnetosphere and Its Association With Plasmapause Positions
Authors: Khoo L.‐Y. , Li X. , Zhao H. , Thaller S. A. , Hogan B.
Published: November 2021

Sudden enhancements of energetic electrons (tens of keV to <500 keV) at low L‐shells have been frequently observed by Van Allen Probes. It is, however, still unclear how deep these electrons can reach and what the responsible mechanisms are. Here we seek to determine the inner boundary of initial enhancements of these energetic electrons and its link with the plasmapause location to offer a new, insightful perspective on this topic. Previous statistical studies have revealed a remarkably consistent observation that initial enhancements of energetic electrons occur mostly at higher L‐shell than the innermost plasmapause locations (Lpp), though a few outlier events were also identified. In this study, we examine the identified outlier events where electron enhancements were reported inside the plasmapause (either in situ Lpp or simulated innermost Lpp). More detailed investigation indicates that the appearance of enhancements inside the in situ Lpp is often associated with duskside observations where the “actual” initial enhancement likely occurs somewhere else, outside the innermost plasmapause location. We thereby urge caution when using the relationship between the observed enhancement locations and the in situ Lpp to infer the effect of electric fields on energetic electrons. In summary, our findings suggest that the innermost Lpp remains the innermost limit of the initial sudden enhancements of energetic electrons. Combining with phase space density analysis, our result implies the role of a large‐scale electric field that leads to sudden electron enhancements and the erosion of the plasmasphere.
Lower Mantle Melting: Experiments and Thermodynamic Modeling in the System MgO‐SiO2
Authors: Yao Jie , Frost Daniel J. , Steinle‐Neumann Gerd
Published: November 2021

Characterizing and modeling melting relations in the system MgO‐SiO2 at lower mantle pressures rely on the location of the eutectic points for MgO‐MgSiO3 and MgSiO3‐SiO2. While at an uppermost lower mantle pressure there is general consensus on the eutectic composition in the former, large discrepancies exist for MgSiO3‐SiO2 from experiments in the diamond anvil cell, ab‐initio simulations and models built on them. In order to address this discrepancy, we have performed multi‐anvil press experiments at GPa for Mg4Si6O16 and Mg3Si7O17 at temperatures of K and K. In the experiments at K, we observe the presence of partial melt. The recovered Mg4Si6O16 sample shows SiO2 stishovite as the liquidus phase, and electron microprobe analysis of the quenched melt determines as the eutectic composition. We fit a thermodynamic model to describe the melting relations in the MgO‐SiO2 system, and extrapolate to core‐mantle boundary pressure. At 136 GPa, we predict that the eutectic points have moved further away from enstatite composition, and solidus temperatures remain similar for MgO‐MgSiO3 and MgSiO3‐SiO2.
Photosensitized Degradation of DMSO Initiated by PAHs at the Air‐Water Interface, as an Alternative Source of Organic Sulfur Compounds to the Atmosphere
Authors: Jiang Haoyu , Carena Luca , He Yingyao , Wang Yiqun , Zhou Wentao , Yang Lihua , Luan Tiangang , Li Xue , Brigante Marcello , Vione Davide , Gligorovski Sasho
Published: November 2021

The photochemical reactions of organic compounds at the water surface lead to the formation of gas‐phase molecules that may contribute to new particle formation in the atmosphere. Here, we observe the formation of organic sulfur (OS) compounds that are known secondary organic aerosol (SOA) precursors, upon irradiation of aqueous solutions containing typical polycyclic aromatic hydrocarbons (PAHs) such as pyrene, fluoranthene, and phenanthrene as well as dimethylsulfoxide (DMSO). The reactivity between the excited triplet states of PAHs (3PAHs*) and DMSO was determined by transient absorption spectroscopy and a tentative reaction mechanism for DMSO degradation was proposed, supported by theoretical calculations of the reaction Gibbs energies. In all cases, we observe rapid formation of methanesulfonic acid, methanesulfinic acid, methylsulfonylmethane, ethyl methanesulfonate, hydroxymethanesulfonic acid, and 2‐hydroxyethanesulfonic acid by use of novel membrane inlet‐single photon ionization‐time of flight mass spectrometry. These results suggest that ubiquitous PAHs and DMSO at the sea surface may represent an alternative source of OS compounds during daytime, through photochemical processes that should be considered in future models to better represent the SOA formation processes in the atmosphere.
AMIP Simulations of a Global Model for Unified Weather‐Climate Forecast: Understanding Precipitation Characteristics and Sensitivity Over East Asia
Authors: Zhang Yi , Yu Rucong , Li Jian , Li Xiaohan , Rong Xinyao , Peng Xindong , Zhou Yihui
Published: November 2021

A global model formulation for unified weather‐climate forecast is evaluated, with emphasis on the climate simulations at typical hydrostatic resolutions. The internal sensitivity is explored by considering different dynamical configurations (resolution, solver type, transport scheme). After a basic assessment of the global mean climate, a detailed analysis of precipitation characteristics is extended to East Asia. The model shows a reasonable mean state, seasonal variation, frequency–intensity structure, and diurnal phase time. The artificial rainfall around the steep slopes of the Tibetan Plateau can be improved through choices in the dynamical configuration. The regional features characterized by “afternoon versus nocturnal‐to‐early‐morning peaks” are properly distinguished. The hourly climatic features are comparable to super‐parameterized CAM5. Different dynamical configurations demonstrate unique sensitivities related to underling physical mechanisms, which are studied from the perspective of the diurnal cycle for three representative regions. Over South China, the higher‐resolution models decrease the weak‐precipitation while increase intense rainfall, thus reducing the dry biases. This is contributed by enhanced grid and sub‐grid scale motions associated with daytime convection progression. Over central western China, the variable‐resolution model better simulates the eastward propagating episodes characterized by a transition from convective to stratiform rainfall along the eastern slope of the Plateau. This reduces the positive biases at the high topography of the Plateau and alleviates the negative biases at the lower foot. Over central eastern China, the model replicates the dominant role of large‐scale governing factors in regulating the early morning rainfall peaks, and produces stratiform heating patterns.
Influences of Extreme Events on Water and Carbon Cycles of Cropland Ecosystems: A Comprehensive Exploration Combining Site and Global Modeling
Authors: Xia Ye , Fu Congsheng , Wu Haohao , Wu Huawu , Zhang Haixia , Cao Yang , Zhu Zichun
Published: November 2021

Climate warming increases the frequencies of drought and excessive precipitation, and the influencing mechanisms and magnitudes of these extreme events on the water and carbon cycles of different crops still remain unclear. In this study, single‐point simulations for six irrigated and rain‐fed crops and global simulation were combined to comprehensively investigate the impacts of drought and excessive precipitation on evapotranspiration (ET), irrigation, net ecosystem exchange (NEE), and yields of crops. Results illustrated that the AgroIBIS‐based CLM5 simulated ET and NEE dynamics well for rice, corn, winter wheat, soybeans, sugar beets, and potatoes after parameter optimization. The impacts of abnormal precipitation on ET, NEE, and crop yield were larger at rain‐fed sites than at irrigated sites. The influencing magnitudes of precipitation shortage on ET depended on the occurring time of drought events relative to the growth stages of crops. Precipitation shortage (excessive precipitation) reduced (increased) ET and net carbon uptake by 4%–19% (4%–7%) and 3%–15% (1%–6%) compared to normal precipitation years at irrigated sites, while corresponding decrease (increase) was 7%–35% (24%–27%) and 19%–48% (12%–34%) at rain‐fed sites. The proportional influencing magnitudes of precipitation shortage on ET, NEE, and yield increased sequentially for rain‐fed crops. At the global scale, the simulated theoretical irrigation in extremely dry years was 25%–75% larger than that in normal precipitation years, and the actual irrigation was 3.5–4.0 times as large as the simulated theoretical value at irrigated sites, implying that drought intensified water resource shortage through excessive irrigation besides precipitation shortage.
Do presenting symptoms, use of pre-diagnostic endoscopy and risk of emergency cancer diagnosis vary by comorbidity burden and type in patients with colorectal cancer?
Authors: Majano Sara Benitez , Lyratzopoulos Georgios , Rachet Bernard , de Wit Niek J. , Renzi Cristina
Published: November 2021

Background

Cancer patients often have pre-existing comorbidities, which can influence timeliness of cancer diagnosis. We examined symptoms, investigations and emergency presentation (EP) risk among colorectal cancer (CRC) patients by comorbidity status.

Methods

Using linked cancer registration, primary care and hospital records of 4836 CRC patients (2011–2015), and multivariate quantile and logistic regression, we examined variations in specialist investigations, diagnostic intervals and EP risk.

Results

Among colon cancer patients, 46% had at least one pre-existing hospital-recorded comorbidity, most frequently cardiovascular disease (CVD, 18%). Comorbid versus non-comorbid cancer patients more frequently had records of anaemia (43% vs 38%), less frequently rectal bleeding/change in bowel habit (20% vs 27%), and longer intervals from symptom-to-first relevant test (median 136 vs 74 days). Comorbid patients were less likely investigated with colonoscopy/sigmoidoscopy, independently of symptoms (adjusted OR = 0.7[0.6, 0.9] for Charlson comorbidity score 1–2 and OR = 0.5 [0.4–0.7] for score 3+ versus 0. EP risk increased with comorbidity score 0, 1, 2, 3+: 23%, 35%, 33%, 47%; adjusted OR = 1.8 [1.4, 2.2]; 1.7 [1.3, 2.3]; 3.0 [2.3, 4.0]) and for patients with CVD (adjusted OR = 2.0 [1.5, 2.5]).

Conclusions

Comorbid individuals with as-yet-undiagnosed CRC often present with general rather than localising symptoms and are less likely promptly investigated with colonoscopy/sigmoidoscopy. Comorbidity is a risk factor for diagnostic delay and has potential, additionally to symptoms, as risk-stratifier for prioritising patients needing prompt assessment to reduce EP.
USP5 facilitates non-small cell lung cancer progression through stabilization of PD-L1
Authors: Pan Jinghua , Qiao Yiting , Chen Congcong , Zang Hongjing , Zhang Xiaojing , Qi Feng , Chang Cunjie , Yang Fan , Sun Mengqing , Lin Shengbin , Tang Quandong , Li Lina , Wang Menglan , Wu Minjie , Liu Yongzhu , Lai Caiyong , Chen Jianxiang , Chen Guo
Published: November 2021

PD-L1(CD274) is a well-known immunosuppressive molecule, which confers immunoescape features to cancer cells and has become one of the major targets in cancer immunotherapies. Understanding the regulatory mechanisms that control PD-L1 protein expression is important for guiding immune checkpoint blockade therapy. Here, we showed that ubiquitin specific peptidase 5 (USP5) was a novel PD-L1 deubiquitinase in non-small cell lung cancer (NSCLC) cells. USP5 directly interacted with PD-L1 and deubiquitinated PD-L1, therefore enhances PD-L1 protein stability. Meanwhile, USP5 protein levels were highly elevated and positively correlated to PD-L1 levels in NSCLC tissues, and were closely correlated with poor prognosis of these patients. In addition, knockdown of USP5 retarded tumor growth in the Lewis lung carcinoma mouse model. Thus, we identified that USP5 was a new regulator of PD-L1 and targeting USP5 is a promising strategy for cancer therapy.
Comparison of culture, confocal microscopy and PCR in routine hospital use for microbial keratitis diagnosis
Authors: Hoffman Jeremy J. , Dart John K. G. , De Surjo K. , Carnt Nicole , Cleary Georgia , Hau Scott
Published: November 2021

Aims

To evaluate the sensitivity and specificity of polymerase chain reaction (PCR), in vivo confocal microscopy (IVCM) and culture for microbial keratitis (MK) diagnosis.

Methods

Retrospective review of PCR, IVCM and culture results for MK diagnosis at Moorfields Eye Hospital between August 2013 and December 2014.

Results

PCR results were available for 259 MK patients with concurrent culture for 203/259 and IVCM for 149/259. Sensitivities and specificities with 95% confidence intervals [95% CI] were calculated for Acanthamoeba keratitis (AK) and fungal keratitis (FK), by comparison with culture, for both IVCM and PCR. For AK, FK and bacterial keratitis (BK) sensitivities were calculated, for each diagnostic method, by comparison with a composite reference standard (a positive result for one or more of culture, PCR or IVCM having a specificity of 100% by definition). For the latter, sensitivities with [95% CI] were: for AK, IVCM 77.1% [62.7–88.0%], PCR 63.3% [48.3–76.6%], culture 35.6 [21.9–51.2]; for FK, IVCM 81.8% [48.2–97.7%], PCR 30.8% [9.09–61.4%], culture 41.7% [15.2–72.3%]; for BK, PCR 25.0% [14.7–37.9%], culture 95.6% [87.6–99.1%].

Conclusion

IVCM was the most sensitive technique for AK and FK diagnosis but culture remains our gold standard for BK. These findings reflect results to be expected from service providers to UK ophthalmology units and demonstrates the need at our centre for ongoing diagnostic result audit leading to the potential to improve PCR diagnosis. Both FK and AK are now common in the UK; ophthalmology units need to have all these techniques available to optimise their MK management.
Middle Ordovician astrochronology decouples asteroid breakup from glacially-induced biotic radiations
Authors: Rasmussen Jan Audun , Thibault Nicolas , Mac Ørum Rasmussen Christian
Published: November 2021

Meso-Cenozoic evidence suggests links between changes in the expression of orbital changes and millennia-scale climatic- and biotic variations, but proof for such shifts in orbital cyclicity farther back in geological time is lacking. Here, we report a 469-million-year-old Palaeozoic energy transfer from precession to 405 kyr eccentricity cycles that coincides with the start of the Great Ordovician Biodiversification Event (GOBE). Based on an early Middle Ordovician astronomically calibrated cyclostratigraphic framework we find this orbital change to succeed the onset of icehouse conditions by 200,000 years, suggesting a climatic origin. Recently, this icehouse was postulated to be facilitated by extra-terrestrial dust associated with an asteroid breakup. Our timescale, however, shows the meteor bombardment to post-date the icehouse by 800,000 years, instead pausing the GOBE 600,000 years after its initiation. Resolving Milankovitch cyclicity in deep time thus suggests universal orbital control in modulating climate, and maybe even biodiversity accumulation, through geological time.