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1.
Meat Sci ; 157: 107870, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31252375

ABSTRACT

Data from samples of longissmus lumborum (LL) and semimembranosus (SM) muscles from 391 lamb carcasses, which had been packaged in overwrap (OW) or high oxygen modified atmosphere packaging (MAPO2) systems and then subjected to simulated retail display, were used to estimate genetic variation for colour stability traits of lamb meat as a step in identifying a trait for genetic evaluation. Traits included the ratio of the reflectance of light at wavelengths of 630 nm and 580 nm (oxy/met) measured at a single time point at the end of the display period (day 3 under OW; day 8 under MAPO2) and the predicted time for oxy/met to reach a benchmark value. Under OW and MAPO2, the measures of meat colour stability of the LL tended to be of moderate heritability (0.09-0.29), but for the SM were of low heritability (0-0.10). Improving retail colour stability of lamb loins through selection of genetically superior animals may be better based on measurement of oxy/met.


Subject(s)
Color , Food Packaging/methods , Red Meat/analysis , Animals , Genetic Variation , Muscle, Skeletal/chemistry , Oxygen , Sheep, Domestic
2.
Reprod Biomed Online ; 36(6): 658-674, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29656830

ABSTRACT

This proceedings report presents the outcomes from an international Expert Meeting to establish a consensus on the recommended technical and operational requirements for air quality within modern assisted reproduction technology (ART) laboratories. Topics considered included design and construction of the facility, as well as its heating, ventilation and air conditioning system; control of particulates, micro-organisms (bacteria, fungi and viruses) and volatile organic compounds (VOCs) within critical areas; safe cleaning practices; operational practices to optimize air quality while minimizing physicochemical risks to gametes and embryos (temperature control versus air flow); and appropriate infection-control practices that minimize exposure to VOC. More than 50 consensus points were established under the general headings of assessing site suitability, basic design criteria for new construction, and laboratory commissioning and ongoing VOC management. These consensus points should be considered as aspirational benchmarks for existing ART laboratories, and as guidelines for the construction of new ART laboratories.


Subject(s)
Air Pollution , Laboratories/standards , Reproductive Techniques, Assisted/standards , Air Pollution, Indoor , Consensus , Environmental Monitoring , Humans
3.
J Anim Sci ; 95(10): 4260-4273, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29108061

ABSTRACT

Genetic correlations between 29 wool production and quality traits and 25 meat quality and nutritional value traits were estimated for Merino sheep from an Information Nucleus (IN). Genetic correlations among the meat quality and nutritional value traits are also reported. The IN comprised 8 flocks linked genetically and managed across a range of sheep production environments in Australia. The wool traits included over 5,000 yearling and 3,700 adult records for fleece weight, fiber diameter, staple length, staple strength, fiber diameter variation, scoured wool color, and visual scores for breech and body wrinkle. The meat quality traits were measured on samples from the and included over 1,200 records from progeny of over 170 sires for intramuscular fat (IMF), shear force of meat aged for 5 d (SF5), 24 h postmortem pH (pHLL; also measured in the , pHST), fresh and retail meat color and meat nutritional value traits such as iron and zinc levels, and long-chain omega-3 and omega-6 polyunsaturated fatty acid levels. Estimated heritabilities for IMF, SF5, pHLL, pHST, retail meat color lightness (), myoglobin, iron, zinc and across the range of long-chain fatty acids were 0.58 ± 0.11, 0.10 ± 0.09, 0.15 ± 0.07, 0.20 ± 0.10, 0.59 ± 0.15, 0.31 ± 0.09, 0.20 ± 0.09, 0.11 ± 0.09, and range of 0.00 (eicosapentaenoic, docosapentaenoic, and arachidonic acids) to 0.14 ± 0.07 (linoleic acid), respectively. The genetic correlations between the wool production and meat quality traits were low to negligible and indicate that wool breeding programs will have little or no effect on meat quality. There were moderately favorable genetic correlations between important yearling wool production traits and the omega-3 fatty acids that were reduced for corresponding adult wool production traits, but these correlations are unlikely to be important in wool/meat breeding programs because they have high SE, and the omega-3 traits have little or no genetic variance. Significant genetic correlations among the meat quality traits included IMF with SF5 (-0.76 ± 0.24), fresh meat color * (0.50 ± 0.18), and zinc (0.41 ± 0.19). Selection to increase IMF will improve meat tenderness and color which may address some of the issues with Merino meat quality. These estimated parameters allow Merino breeders to combine wool and meat objectives without compromising meat quality.


Subject(s)
Meat/standards , Sheep/genetics , Wool/standards , Animals , Australia , Body Weight/genetics , Breeding , Color , Fatty Acids/analysis , Female , Iron/analysis , Male , Nutritive Value/genetics , Phenotype , Sheep/physiology , Zinc/analysis
4.
J Anim Sci ; 95(5): 1879-1891, 2017 May.
Article in English | MEDLINE | ID: mdl-28726993

ABSTRACT

Genetic correlations between 29 wool production and quality traits and live weight and ultrasound fat depth (FAT) and eye muscle depth (EMD) traits were estimated from the Information Nucleus (IN). The IN comprised 8 genetically linked flocks managed across a range of Australian sheep production environments. The data were from a maximum of 9,135 progeny born over 5 yr from 184 Merino sires and 4,614 Merino dams. The wool traits included records for yearling and adult fleece weight, fiber diameter (FD), staple length (SL), fiber diameter CV (FDCV), scoured color, and visual scores for breech and body wrinkle. We found high heritability for the major yearling wool production traits and some wool quality traits, whereas other wool quality traits, wool color, and visual traits were moderately heritable. The estimates of heritability for live weight generally increased with age as maternal effects declined. Estimates of heritability for the ultrasound traits were also higher when measured at yearling age rather than at postweaning age. The genetic correlations for fleece weight with live weights were positive (favorable) and moderate (approximately 0.5 ± 0.1), whereas those with FD were approximately 0.3 (unfavorable). The other wool traits had lower genetic correlations with the live weights. The genetic correlations for FAT and EMD with FD and SL were positive and low, with FDCV low to moderate negative, but variable with wool weight and negligible for the other wool traits. The genetic correlations for FAT and EMD with postweaning weight were positive and high (0.61 ± 0.18 to 0.75 ± 0.14) but were generally moderate with weights at other ages. Selection for increased live weight will result in a moderate correlated increase in wool weight as well as favorable reductions in breech cover and wrinkle, along with some unfavorable increases in FD and wool yellowness but little impact on other wool traits. The ultrasound meat traits, FAT and EMD, were highly positively genetically correlated (0.8), and selection to increase them would result in a small unfavorable correlated increase in FD, moderately favorable reductions in breech cover and wrinkle, but equivocal or negligible changes in other wool traits. The estimated parameters provide the basis for calculation of more accurate Australian Sheep Breeding Values and selection indexes that combine wool and meat objectives in Merino breeding programs.


Subject(s)
Red Meat/standards , Sheep/genetics , Wool/growth & development , Animals , Australia , Body Weight , Breeding , Female , Genotype , Male , Phenotype , Pregnancy , Sheep/anatomy & histology , Sheep/growth & development
5.
J Anim Sci ; 95(6): 2385-2398, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28727038

ABSTRACT

Genetic correlations between 29 wool production and quality traits and 14 whole carcass measures and carcass component traits were estimated from the Information Nucleus of 8 flocks managed across a range of Australian sheep production environments and genetically linked. Wool data were from over 5,000 Merino progeny born over 5 yr, whereas carcass data were from over 1,200 wether progeny of over 176 sires, slaughtered at about 21 kg carcass weight, on average. Wool traits included yearling and adult records for wool weight, fiber diameter, fiber diameter variation, staple strength, scoured color, and visual scores for breech and body wrinkle. Whole carcass measures included HCW, dressing percentage (DP), and various measures of fat depth and eye muscle dimensions. Carcass components were obtained by dissection, and lean meat yield (LMY) was predicted. Heritability estimates for whole carcass measures ranged from 0.12 ± 0.08 to 0.35 ± 0.10 and ranged from 0.17 ± 0.10 to 0.46 ± 0.10 for carcass dissection traits, with no evidence of important genotype × environment interactions. Genetic correlations indicated that selection for increased clean wool weight will result in reduced carcass fat (-0.17 to -0.34) and DP (-0.48 ± 0.15), with little effect on carcass muscle. Selection for lower fiber diameter will reduce HCW (-0.48 ± 0.15) as well as carcass fat (0.14 to 0.27) and muscle (0.21 to 0.50). There were high genetic correlations between live animal measures of fat and muscle depth and the carcass traits (generally greater than 0.5 in size). Selection to increase HCW (and DP) will result in sheep with fewer wrinkles on the body (-0.57 ± 0.10) and barer breeches (-0.74 ± 0.12, favorable), with minor deterioration in scoured wool color (reduced brightness and increased yellowness). Selection for reduced fat will also result in sheep with fewer body wrinkles (-0.42 to -0.79). Increasing LMY in Merinos through selection would result in a large reduction in carcass fat and DP (-0.66 to -0.84), with a smaller increase in carcass muscle and some increase in wool weight and wrinkles. Although no major antagonisms are apparent between the wool and carcass traits, developing selection indexes for dual-purpose wool and meat breeding objectives will require accurate estimates of genetic parameters to ensure that unfavorable relationships are suitably considered. The findings will aid development of dual-purpose wool and meat breeding objectives.


Subject(s)
Sheep/genetics , Wool/growth & development , Animals , Australia , Body Weight , Breeding , Color , Female , Genotype , Male , Phenotype , Red Meat , Sheep/growth & development
6.
mBio ; 5(4): e01157-14, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-25028422

ABSTRACT

Soil microbial diversity represents the largest global reservoir of novel microorganisms and enzymes. In this study, we coupled functional metagenomics and DNA stable-isotope probing (DNA-SIP) using multiple plant-derived carbon substrates and diverse soils to characterize active soil bacterial communities and their glycoside hydrolase genes, which have value for industrial applications. We incubated samples from three disparate Canadian soils (tundra, temperate rainforest, and agricultural) with five native carbon ((12)C) or stable-isotope-labeled ((13)C) carbohydrates (glucose, cellobiose, xylose, arabinose, and cellulose). Indicator species analysis revealed high specificity and fidelity for many uncultured and unclassified bacterial taxa in the heavy DNA for all soils and substrates. Among characterized taxa, Actinomycetales (Salinibacterium), Rhizobiales (Devosia), Rhodospirillales (Telmatospirillum), and Caulobacterales (Phenylobacterium and Asticcacaulis) were bacterial indicator species for the heavy substrates and soils tested. Both Actinomycetales and Caulobacterales (Phenylobacterium) were associated with metabolism of cellulose, and Alphaproteobacteria were associated with the metabolism of arabinose; members of the order Rhizobiales were strongly associated with the metabolism of xylose. Annotated metagenomic data suggested diverse glycoside hydrolase gene representation within the pooled heavy DNA. By screening 2,876 cloned fragments derived from the (13)C-labeled DNA isolated from soils incubated with cellulose, we demonstrate the power of combining DNA-SIP, multiple-displacement amplification (MDA), and functional metagenomics by efficiently isolating multiple clones with activity on carboxymethyl cellulose and fluorogenic proxy substrates for carbohydrate-active enzymes. Importance: The ability to identify genes based on function, instead of sequence homology, allows the discovery of genes that would not be identified through sequence alone. This is arguably the most powerful application of metagenomics for the recovery of novel genes and a natural partner of the stable-isotope-probing approach for targeting active-yet-uncultured microorganisms. We expanded on previous efforts to combine stable-isotope probing and metagenomics, enriching microorganisms from multiple soils that were active in degrading plant-derived carbohydrates, followed by construction of a cellulose-based metagenomic library and recovery of glycoside hydrolases through functional metagenomics. The major advance of our study was the discovery of active-yet-uncultivated soil microorganisms and enrichment of their glycoside hydrolases. We recovered positive cosmid clones in a higher frequency than would be expected with direct metagenomic analysis of soil DNA. This study has generated an invaluable metagenomic resource that future research will exploit for genetic and enzymatic potential.


Subject(s)
Isotope Labeling/methods , Metagenomics/methods , Soil Microbiology , Actinomycetales/classification , Actinomycetales/genetics , Caulobacteraceae/drug effects , Caulobacteraceae/genetics , Molecular Sequence Data , Rhodospirillales/classification , Rhodospirillales/genetics
7.
Meat Sci ; 98(3): 544-55, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24930628

ABSTRACT

Subtle breed differences exist for meat quality traits and the Merino does stand out, although many comparisons are confounded by production site or lack of processing intervention. Despite this, the Merino does seem to have a propensity to produce meat with a higher pH and reduced colour stability under extended ageing. Use of the Merino in a crossbreeding system not only provides benefits from hybrid vigour, but also overcomes the meat quality constraints of pure Merinos. Genetic evaluation for lamb production has enabled impressive genetic gains, but an overemphasis on lean meat production has had to be addressed to counter adverse effects on meat quality traits like eating quality. In this regard, the development of genomic selection has provided a methodology for accurate prediction of genetic merit and applying balanced breeding objectives. The potential for negative meat quality effects has stemmed adoption of non-castration approaches, but ensuring that lamb is young when slaughtered does provide brand integrity.


Subject(s)
Genotype , Hybridization, Genetic , Meat/analysis , Phenotype , Animals , Crosses, Genetic , Diet , Female , Genome , Hybrid Vigor , Male , Meat/standards , Sheep, Domestic/genetics
8.
Meat Sci ; 96(2 Pt B): 1016-24, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24084607

ABSTRACT

Genetic parameters were estimated for a range of meat quality traits recorded on Australian lamb meat. Data were collected from Merino and crossbred progeny of Merino, terminal and maternal meat breed sires of the Information Nucleus programme. Lambs born between 2007 and 2010 (n=8968) were slaughtered, these being the progeny of 372 sires and 5309 dams. Meat quality traits were found generally to be of moderate heritability (estimates between 0.15 and 0.30 for measures of meat tenderness, meat colour, polyunsaturated fat content, mineral content and muscle oxidative capacity), with notable exceptions of intramuscular fat (0.48), ultimate pH (0.08) and fresh meat colour a* (0.08) and b* (0.10) values. Genetic correlations between hot carcass weight and the meat quality traits were low. The genetic correlation between intramuscular fat and shear force was high (-0.62). Several measures of meat quality (fresh meat redness, retail meat redness, retail oxy/met value and iron content) appear to have potential for inclusion in meat sheep breeding objectives.


Subject(s)
Breeding , Diet , Meat/analysis , Phenotype , Sheep, Domestic/genetics , Adipose Tissue/metabolism , Animals , Australia , Body Weight/genetics , Color , Dietary Fats/metabolism , Fatty Acids, Unsaturated/genetics , Fatty Acids, Unsaturated/metabolism , Humans , Hydrogen-Ion Concentration , Iron/metabolism , Meat/standards , Minerals/metabolism , Nutritive Value , Oxidation-Reduction , Stress, Mechanical
9.
QJM ; 104(11): 957-70, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21752867

ABSTRACT

BACKGROUND: Bortezomib is approved for the treatment of multiple myeloma and a role has been suggested in the treatment of systemic AL amyloidosis (AL). METHODS: In this phase 1 dose-escalation portion of the first prospective study of single-agent bortezomib in AL, 31 patients with relapsed disease, including 14 (45%) with cardiac involvement, received bortezomib in seven dose cohorts on once-weekly (0.7, 1.0, 1.3, 1.6 mg/m(2)) and twice-weekly (0.7, 1.0, 1.3 mg/m(2)) schedules. Electrocardiographic, Holter and echocardiographic studies were evaluated in all patients to determine safety and response. RESULTS: During therapy (median treatment period 210 days), no patient developed significant ventricular or supraventricular rhythm disturbance on 24-h Holter monitoring; however, no patient satisfied study criteria for cardiac response using echocardiographic assessment or New York Heart Association classification. Seven patients (23%) had a ≥ 10% fall in left ventricular ejection fraction, but only one met criteria for cardiac deterioration. The predominant cardiac adverse events were peripheral edema (23%), orthostatic hypotension (13%) and hypotension (10%). Two patients developed grade 3 congestive heart failure, which resolved following treatment interruption. In this Phase 1 portion, the maximum tolerated dose of bortezomib on either schedule was not reached. Hematologic responses occurred in 14 patients (45%), including seven (23%) complete responses. In non-responders mean left ventricular wall thickness increased during the course of treatment. CONCLUSION: AL is frequently rapidly progressive; in these patients who had relapsed or progressed following previous conventional therapies, these results suggest that bortezomib may slow the progression of cardiac amyloid with limited toxicity.


Subject(s)
Amyloidosis/drug therapy , Antineoplastic Agents/administration & dosage , Boronic Acids/administration & dosage , Heart Diseases/drug therapy , Pyrazines/administration & dosage , Aged , Amyloidosis/complications , Bortezomib , Disease Progression , Dose-Response Relationship, Drug , Drug Administration Schedule , Electrocardiography , Female , Heart Diseases/etiology , Humans , Kidney Diseases/drug therapy , Kidney Diseases/etiology , Liver Diseases/drug therapy , Liver Diseases/etiology , Male , Maximum Tolerated Dose , Middle Aged , Paraproteinemias/complications , Peripheral Nervous System Diseases/drug therapy , Peripheral Nervous System Diseases/etiology , Prospective Studies , Treatment Outcome
10.
J Environ Manage ; 92(3): 902-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21075506

ABSTRACT

Agri-environment schemes (AESs) have been implemented across EU member states in an attempt to reconcile agricultural production methods with protection of the environment and maintenance of the countryside. To determine the extent to which such policy objectives are being fulfilled, participating countries are obliged to monitor and evaluate the environmental, agricultural and socio-economic impacts of their AESs. However, few evaluations measure precise environmental outcomes and critically, there are no agreed methodologies to evaluate the benefits of particular agri-environmental measures, or to track the environmental consequences of changing agricultural practices. In response to these issues, the Agri-Environmental Footprint project developed a common methodology for assessing the environmental impact of European AES. The Agri-Environmental Footprint Index (AFI) is a farm-level, adaptable methodology that aggregates measurements of agri-environmental indicators based on Multi-Criteria Analysis (MCA) techniques. The method was developed specifically to allow assessment of differences in the environmental performance of farms according to participation in agri-environment schemes. The AFI methodology is constructed so that high values represent good environmental performance. This paper explores the use of the AFI methodology in combination with Farm Business Survey data collected in England for the Farm Accountancy Data Network (FADN), to test whether its use could be extended for the routine surveillance of environmental performance of farming systems using established data sources. Overall, the aim was to measure the environmental impact of three different types of agriculture (arable, lowland livestock and upland livestock) in England and to identify differences in AFI due to participation in agri-environment schemes. However, because farm size, farmer age, level of education and region are also likely to influence the environmental performance of a holding, these factors were also considered. Application of the methodology revealed that only arable holdings participating in agri-environment schemes had a greater environmental performance, although responses differed between regions. Of the other explanatory variables explored, the key factors determining the environmental performance for lowland livestock holdings were farm size, farmer age and level of education. In contrast, the AFI value of upland livestock holdings differed only between regions. The paper demonstrates that the AFI methodology can be used readily with English FADN data and therefore has the potential to be applied more widely to similar data sources routinely collected across the EU-27 in a standardised manner.


Subject(s)
Agriculture , Environmental Monitoring , Livestock , Animals , European Union , Humans , Middle Aged
11.
J Anim Breed Genet ; 125(3): 205-15, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18479272

ABSTRACT

Genetic parameters for carcass and meat quality traits of about 18-month-old Merino rams (n = 5870), the progeny of 543 sires from three research resource flocks, were estimated. The estimates of heritability for hot carcass weight (HCW) and the various fat and muscle dimension measurements were moderate and ranged from 0.20 to 0.37. The brightness of meat (colour L*, 0.18 +/- 0.03 standard error) and meat pH (0.22 +/- 0.03) also had moderate estimates of heritability, although meat relative redness (colour a*, 0.10 +/- 0.03) and relative yellowness (colour b*, 0.10 +/- 0.03) were lower. Heritability estimates for live weights were moderate and ranged from 0.29 to 0.41 with significant permanent maternal environmental effects (0.13 to 0.10). The heritability estimates for the hogget wool traits were moderate to high and ranged from 0.27 to 0.60. The ultrasound measurements of fat depth (FATUS) and eye muscle depth (EMDUS) on live animals were highly genetically correlated with the corresponding carcass measurements (0.69 +/- 0.09 FATC and 0.77 +/- 0.07 EMD). Carcass tissue depth (FATGR) had moderate to low genetic correlations with carcass muscle measurements [0.18 +/- 0.10 EMD and 0.05 +/- 0.10 eye muscle area (EMA)], while those with FATC were negative. The genetic correlation between EMD and eye muscle width (EMW) was 0.41 +/- 0.08, while EMA was highly correlated with EMD (0.89 +/- 0.0) and EMW (0.78 +/- 0.04). The genetic correlations for muscle colour with muscle measurements were moderately negative, while those with fat measurements were close to zero. Meat pH was positively correlated with muscle measurements (0.14 to 0.17) and negatively correlated with fat measurements (-0.06 to -0.18). EMDUS also showed a similar pattern of correlations to EMD with meat quality indicator traits, although FATUS had positive correlations with these traits which were generally smaller than their standard error. The genetic correlations among the meat colour traits were high and positive while those with meat pH were high and negative, which were all in the favourable direction. Generally, phenotypic correlations were similar or slightly lower than the corresponding genetic correlations. There were generally small to moderate negative genetic correlations between clean fleece weight (CFW) and carcass fat traits while those with muscle traits were close to zero. As the Merino is already a relatively lean breed, this implies that particular attention should be given to this relationship in Merino breeding programmes to prevent the reduction of fat reserves as a correlated response to selection for increased fleece weight. The ultrasound scan traits generally showed a similar pattern to the corresponding carcass fat and muscle traits. There was a small unfavourable genetic correlation between CFW and meat pH (0.19 +/- 0.07).


Subject(s)
Sheep/anatomy & histology , Sheep/genetics , Animals , Australia , Body Weight/genetics , Linear Models , Male , Models, Genetic , Sheep/growth & development , Species Specificity , Wool/growth & development
12.
J Anim Breed Genet ; 125(6): 397-402, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19134075

ABSTRACT

Genetic correlations between reproduction traits in ewes and carcass and meat quality traits in Merino rams were obtained using restricted maximum likelihood procedures. The carcass data were from 5870 Merino rams slaughtered at approximately 18 months of age that were the progeny of 543 sires from three research resource flocks over 7 years. The carcass traits included ultrasound scan fat and eye muscle depth (EMDUS) measured on live animals, dressing percentage and carcass tissue depth (at the GR site FATGR and C site FATC), eye muscle depth, width and area and the meat quality indicator traits of muscle final pH and colour (L*, a*, b*). The reproduction data consisted of 13 464 ewe joining records for number of lambs born and weaned and 9015 records for LS. The genetic correlations between reproduction and fat measurements were negative (range -0.06 +/- 0.12 to -0.37 +/- 0.12), with smaller correlations for live measurement than carcass traits. There were small favourable genetic correlations between reproduction traits and muscle depth in live rams (EMDUS, 0.10 +/- 0.12 to 0.20 +/- 0.12), although those with carcass muscle traits were close to zero. The reproduction traits were independent of meat colour L* (relative brightness), but tended to be favourably correlated with meat colour a* (relative redness, 0.12 +/- 0.17 to 0.19 +/- 0.16). There was a tendency for meat final pH to have small negative favourable genetic correlations with reproduction traits (0.05 +/- 0.11 to -0.17 +/- 0.12). This study indicates that there is no antagonism between reproduction traits and carcass and meat quality indicator traits, with scope for joint improvement of reproduction, carcass and meat quality traits in Merino sheep.


Subject(s)
Breeding , Meat/standards , Reproduction/genetics , Sheep, Domestic/genetics , Animals , Female , Male , Sheep, Domestic/physiology
13.
Oecologia ; 154(4): 773-83, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17972106

ABSTRACT

Over the last 60 years changes to the management of species-rich mesotrophic grasslands have resulted in the large-scale loss and degradation of this habitat across Europe. Restoration of such grasslands on agriculturally improved pastures provides a potentially valuable approach to the conservation of these threatened areas. Over a four-year period a replicated block design was used to test the effects of seed addition (green hay spreading and brush harvest collection) and soil disturbance on the restoration of phytophagous beetle and plant communities. Patterns of increasing restoration success, particularly where hay spreading and soil disturbance were used in combination, were identified for the phytophagous beetles. In the case of the plants, however, initial differences in restoration success in response to these same treatments were not followed by subsequent temporal changes in plant community similarity to target mesotrophic grassland. It is possible that the long-term consequences of the management treatments would not be the establishment of beetle and plant communities characteristic of the targets for restoration. Restoration management to enhance plant establishment using hay spreading and soil disturbance techniques would, however, still increase community similarity in both taxa to that of species-rich mesotrophic grasslands, and so raise their conservation value.


Subject(s)
Coleoptera , Conservation of Natural Resources , Ecosystem , Poaceae , Animals , England , Seeds , Soil
14.
J Anim Breed Genet ; 124(2): 65-72, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17488356

ABSTRACT

Data from seven research resource flocks across Australia were combined to provide accurate estimates of genetic correlations among production traits in Merino sheep. The flocks represented contemporary Australian Merino fine, medium and broad wool strains over the past 30 years. Over 110,000 records were available for analysis for each of the major wool traits, and 50,000 records for reproduction and growth traits with over 2700 sires and 25,000 dams. Individual models developed from the single trait analyses were extended to the various combinations of two-trait models to obtain genetic correlations among six wool traits [clean fleece weight (CFW), greasy fleece weight, fibre diameter (FD), yield, coefficient of variation of fibre diameter and standard deviation of fibre diameter], four growth traits [birth weight, weaning weight, yearling weight (YWT), and hogget weight] and four reproduction traits [fertility, litter size, lambs born per ewe joined, lambs weaned per ewe joined (LW/EJ)]. This study has provided for the first time a comprehensive matrix of genetic correlations among these 14 wool, growth and reproduction traits. The large size of the data set has also provided estimates with very low standard errors. A moderate positive genetic correlation was observed between CFW and FD (0.29 +/- 0.02). YWT was positively correlated with CFW (0.23 +/- 0.04), FD (0.17 +/- 0.04) and LWEJ (0.58 +/- 0.06), while LW/EJ was negatively correlated with CFW (-0.26 +/- 0.05) and positively correlated with FD (0.06 +/- 0.04) and LS (0.68 +/- 0.04). These genetic correlations, together with the estimates of heritability and other parameters provide the basis for more accurate prediction of outcomes in complex sheep-breeding programmes designed to improve several traits.


Subject(s)
Breeding/statistics & numerical data , Reproduction/physiology , Sheep/growth & development , Sheep/genetics , Wool/growth & development , Animals , Australia , Body Weights and Measures , Fertility/physiology , Litter Size , Models, Genetic , Sheep/physiology , Wool/anatomy & histology
16.
Basic Res Cardiol ; 95(2): 119-26, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10826504

ABSTRACT

Brief myocardial ischemia (ISC) is known to attenuate purine metabolite accumulation in the interstitial fluid (ISF) during subsequent ISC. We determined how this attenuated purine accumulation was altered by 1) extended reperfusion (REP) and 2) multiple cycles of brief ISC. Microdialysis probes were used to assess ISF levels of the purine metabolites adenosine, inosine, and hypoxanthine in anesthetized rabbits. In one series of experiments, two 10 min periods of regional ISC were separated by 10 (n = 6), 60 (n = 6), or 180 (n = 6) min of REP. In the 10, 60, and 180 min REP groups the increase in ISF purine metabolites during the second ISC was 47%, 55%, and 53% of that seen during the first ISC, respectively. In a second series of experiments, hearts were exposed to 120 min of ISC with (n = 6) or without (n = 6) five preceding cycles of transient ISC (10 min ISC; 10 min of REP). The increase in ISF purine metabolites during the multiple cycles of ISC was progressively attenuated, and there was a delay but eventual increase in ISF purine metabolites during the 120 min ISC. These data demonstrate that attenuated purine metabolite accumulation 1) is progressively greater with multiple cycles of brief ISC, 2) has a memory time of at least 180 min, and 3) is not due to high energy phosphate depletion.


Subject(s)
Ischemic Preconditioning , Myocardial Ischemia/metabolism , Purines/metabolism , Animals , Hemodynamics , Male , Microdialysis , Rabbits
17.
Am J Surg Pathol ; 24(3): 459-63, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10716161

ABSTRACT

The authors report an unusual case of peripheral T-cell lymphoma in a 16-year-old boy who presented initially with jaundice, splenomegaly, anemia, and thrombocytopenia. A lymphoma was found subsequently in the spleen, which was infiltrated extensively in the red pulp by medium-sized, blastic-appearing lymphoma cells. Immunologic characterization of these cells revealed positivity for CD3, CD5, CD45RO, CD56, and T-cell intracellular antigen (TIA), and negativity for CD2, CD3, CD4, CD8, CD57, CD34, and terminal deoxynucleotidyl transferase (TdT). Conventional cytogenetic studies revealed the presence of isochromosome 7q. On follow up, this patient deteriorated rapidly, with evidence of liver and bone marrow involvement. Although the overall clinical and pathologic features of this disease were characteristic of hepatosplenic gammadelta T-cell lymphoma, the T-cell receptor of this tumor showed an immunophenotype of alphabeta not gammadelta lineage. Using the Southern blot technique, the authors demonstrated monoclonal gene rearrangement of the T-cell receptor beta-chain. Thus, they confirmed the existence of hepatosplenic alphabeta T-cell lymphoma. In view of its overall similarity to hepatosplenic gammadelta T-cell lymphoma, this unusual entity probably represents a slight biologic variation of the same disease.


Subject(s)
Anemia, Hemolytic/etiology , Liver Neoplasms/complications , Lymphoma, T-Cell/complications , Splenic Neoplasms/complications , Thrombocytopenia/etiology , Adolescent , Humans , Liver Neoplasms/pathology , Lymphoma, T-Cell/pathology , Male , Splenic Neoplasms/pathology
18.
Oecologia ; 124(1): 91-99, 2000 Jul.
Article in English | MEDLINE | ID: mdl-28308417

ABSTRACT

Succession is one of the most studied processes in ecology and succession theory provides strong predictability. However, few attempts have been made to influence the course of succession thereby testing the hypothesis that passing through one stage is essential before entering the next one. At each stage of succession ecosystem processes may be affected by the diversity of species present, but there is little empirical evidence showing that plant species diversity may affect succession. On ex-arable land, a major constraint of vegetation succession is the dominance of perennial early-successional (arable weed) species. Our aim was to change the initial vegetation succession by the direct sowing of later-successional plant species. The hypothesis was tested that a diverse plant species mixture would be more successful in weed suppression than species-poor mixtures. In order to provide a robust test including a wide range of environmental conditions and plant species, experiments were carried out at five sites across Europe. At each site, an identical experiment was set up, albeit that the plant species composition of the sown mixtures differed from site to site. Results of the 2-year study showed that diverse plant species mixtures were more effective at reducing the number of natural colonisers (mainly weeds from the seed bank) than the average low-diversity treatment. However, the effect of the low-diversity treatment depended on the composition of the species mixture. Thus, the effect of enhanced species diversity strongly depended on the species composition of the low-diversity treatments used for comparison. The effects of high-diversity plant species mixtures on weed suppression differed between sites. Low-productivity sites gave the weakest response to the diversity treatments. These differences among sites did not change the general pattern. The present results have implications for understanding biological invasions. It has been hypothesised that alien species are more likely to invade species-poor communities than communities with high diversity. However, our results show that the identity of the local species matters. This may explain, at least partly, controversial results of studies on the relation between local diversity and the probability of being invaded by aliens.

19.
Clin Transplant ; 13(5): 426-31, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10515224

ABSTRACT

PURPOSE: Limited options are available to improve the functional class of patients awaiting cardiac transplantation. We assessed the effect of carvedilol on New York Heart Association (NYHA) class, heart rate (HR), blood pressure (BP), jugular venous pressure (JVP), electrolytes and renal function in patients with markedly decreased left ventricular (LV) function referred for cardiac transplantation assessment. METHODS: Sixty-one patients (age = 52 +/- 12 yr, EF = 23 +/- 7%, VO2 max = 16 +/- 5 mL/kg/min) referred to the cardiac transplant clinic were reviewed before and after the addition of carvedilol (starting dose 3.125 mg twice daily to target dose of 25 mg twice daily) to usual heart-failure therapy. Over a 1-yr period, at each visit prior to initiation, at baseline initiation visit and at each follow-up visit, NYHA class, BP, HR, JVP, electrolytes, and renal function were obtained. Statistical analysis was performed using random effects regression approach. A multiple logistic regression analysis was performed on 52/61 patients to determine possible associations between NYHA improvement and the following patient characteristics: sex, etiology of cardiomyopathy, initial NYHA class, and dose of carvedilol. RESULTS: Three patients died (2 after stopping carvedilol) and 3 were transplanted. Median follow-up was 100 d. Sixteen patients reached the target dose after a mean of 137 d (2.75 visits). Estimated time-to-target dose is 8 months (5.6 visits). BP tended to increase (p = 0.07 for change in trend) with no change in JVP, electrolytes or renal function. HR decreased 6 +/- 3 b.p.m. (p = 0.03). Of 14 patients NYHA class I/II at baseline, none were class III/IV at last follow-up visit. Of 47 patients NYHA class III/IV at baseline, 25 were class I/II, and 22 were class III/IV at last follow-up (p < 0.001). Multiple logistic regression analysis did not demonstrate any factor predictive of subsequent NYHA class improvement. CONCLUSIONS: Despite less than target doses in most patients, a favorable effect of carvedilol on functional class in patients with severe congestive heart failure (CHF) referred for transplant was observed. Those with good functional status remained stable and those with poor functional status improved or remained stable. No baseline patient characteristic predicted improvement. The shortage of donor organ requires optimal use of medical regimens which may improve functional class while awaiting transplantation and which may delay the necessity for heart transplantation. Therefore, addition of carvedilol to usual medical therapy may be beneficial even in patients with severe LV dysfunction and poor NYHA classification.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Carbazoles/therapeutic use , Heart Failure/physiopathology , Heart Transplantation , Propanolamines/therapeutic use , Ventricular Dysfunction, Left/physiopathology , Blood Pressure/drug effects , Carvedilol , Heart Failure/drug therapy , Heart Failure/surgery , Heart Rate/drug effects , Humans , Kidney/physiopathology , Middle Aged , Venous Pressure/drug effects , Ventricular Dysfunction, Left/drug therapy , Ventricular Dysfunction, Left/surgery
20.
Hum Reprod ; 14(4): 986-96, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10221232

ABSTRACT

The kinematic values which are determined relative to the average path by computer-aided sperm analysis (CASA) instruments are reliant upon the algorithm used for track smoothing, and therefore may differ depending upon the shape and complexity of the trajectories analysed. To overcome this potential source of error in the identification of particular trajectory patterns, kinematic values must be derived so that they are independent of the average path. In this study a number of novel kinematic measures were developed and tested for their ability to differentiate between hyperactivated and non-hyperactivated human spermatozoa. A definition for hyperactivation which relied solely upon smoothing-independent kinematic values was developed. This definition was tested on two groups of trajectories reconstructed at 60 Hz by a CASA instrument. An overall agreement of 99% between the classification of tracks as hyperactivated or non-hyperactivated was observed between the established 60 Hz definition validated for that particular CASA instrument and the new, smoothing-independent definition. Because the new values are only reliant upon (x,y) coordinates for their calculation, and do not require smoothing, it should not be difficult to incorporate them into existing CASA instruments.


Subject(s)
Biological Assay , Sperm Capacitation , Sperm Motility , Adult , Biomechanical Phenomena , Humans , Male
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