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1.
Animal ; 16(4): 100490, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35306467

RESUMEN

Greenhouse gas emissions from Western Australia's sheep flock account for 26% of the state's agricultural emissions, principally as a result of enteric methane emissions. A decrease in emissions between 2005 and 2019 can be partly explained by a 44% drop in sheep numbers over that period, but less is known about potential changes in the methane intensity of sheepmeat and wool kg CO2 equivalents/kg product. Using the livestock systems modelling software GrassGro™, we assessed the changes in methane intensity of sheepmeat and wool produced in two major sheep-producing regions in Western Australia. We also evaluated a series of future scenarios. Our results demonstrate that the observed emissions reductions are largely a result of a decrease in flock size, although methane intensity has also decreased somewhat by 11.1%. Simulation of future trajectories indicates that methane intensity could be as much as 18.8% lower by 2030, compared to 2005, with further reductions of up to 42% considered possible. The primary driver of the decreased methane intensity to date is increased flock reproductive performance through increased marking rates, higher rates of ewe lamb mating, and lower ewe death rates. However, despite reductions in methane intensity per kg of product, net emissions per ewe have risen 11.6% since 2005 and are forecast to rise by up to 21.8% by 2030, with potential further increases of up to 61% considered possible. This is driven by increased feed intake due to an increased number of lambs produced per ewe, higher ewe standard reference weights, and lower ewe death rates. Therefore, achieving absolute net reductions in the methane emissions through productivity improvements is unlikely to be prospective. Reducing net emissions is instead likely to be contingent on a reduction in flock numbers, breakthroughs in anti-methanogenic research, or via emissions offsetting. Our approach can be applied in other major livestock producing regions to evaluate emissions performance, with potential implications for agricultural and trade policy as markets increasingly seek lower emissions product.


Asunto(s)
Gases de Efecto Invernadero , Lana , Animales , Femenino , Ganado , Metano , Estudios Prospectivos , Ovinos
2.
Animal ; 15(12): 100392, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34844185

RESUMEN

Ruminant red meat production systems around the world often include a grain feeding phase. The role of red meat in the food system is therefore often discussed in terms of the food vs feed debate, as well as invoking the comparatively poor feed conversion efficiency of ruminants and climate impacts from enteric methane. The concept of net protein contribution (NPC) incorporates the quality attributes of protein produced by livestock systems into estimates of the efficiency of production systems. We applied the NPC method to two Australian beef supply chains, i) Grass-fed and ii) Grain-finished beef, using an established model of ruminant grazing systems (GrassGro®) and these are reflective of beef production systems in other countries. The beef supply chains evaluated did not compete with humans for protein. The Grain-finished beef supply chain, while positively contributing to human protein requirements (NPC value 1.96), had markedly lower NPC values than the Grass-fed system (NPC value 1 597). However, Grass-fed beef production systems have a higher methane intensity than the Grain-finished supply chain. The two examples of pasture-based beef production systems examined provide a positive net protein contribution to human food supply, even with extended periods of finishing on grain-based diets. This is achieved by ruminant grazing on pastures converting low-quality forage into high value human edible protein. The efficiency of protein production varies according to the system design, and other considerations such as land use and enteric methane production are elements that need consideration in the overall assessment of the production footprint.


Asunto(s)
Alimentación Animal , Grano Comestible , Alimentación Animal/análisis , Animales , Australia , Bovinos , Dieta , Metano
3.
Animal ; 12(9): 1967-1980, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29198288

RESUMEN

Highly variable climates induce large variability in the supply of forage for livestock and so farmers must manage their livestock systems to reduce the risk of feed gaps (i.e. periods when livestock feed demand exceeds forage supply). However, mixed crop-livestock farmers can utilise a range of feed sources on their farms to help mitigate these risks. This paper reports on the development and application of a simple whole-farm feed-energy balance calculator which is used to evaluate the frequency and magnitude of feed gaps. The calculator matches long-term simulations of variation in forage and metabolisable energy supply from diverse sources against energy demand for different livestock enterprises. Scenarios of increasing the diversity of forage sources in livestock systems is investigated for six locations selected to span Australia's crop-livestock zone. We found that systems relying on only one feed source were prone to higher risk of feed gaps, and hence, would often have to reduce stocking rates to mitigate these risks or use supplementary feed. At all sites, by adding more feed sources to the farm feedbase the continuity of supply of both fresh and carry-over forage was improved, reducing the frequency and magnitude of feed deficits. However, there were diminishing returns from making the feedbase more complex, with combinations of two to three feed sources typically achieving the maximum benefits in terms of reducing the risk of feed gaps. Higher stocking rates could be maintained while limiting risk when combinations of other feed sources were introduced into the feedbase. For the same level of risk, a feedbase relying on a diversity of forage sources could support stocking rates 1.4 to 3 times higher than if they were using a single pasture source. This suggests that there is significant capacity to mitigate both risk of feed gaps at the same time as increasing 'safe' stocking rates through better integration of feed sources on mixed crop-livestock farms across diverse regions and climates.


Asunto(s)
Alimentación Animal , Clima , Ganado , Animales , Australia , Agricultores , Granjas
4.
Animal ; 10(2): 183-91, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26355660

RESUMEN

Given the capacity of ruminants to modify diet selection based on metabolic needs, we hypothesised that, when given a choice, lambs experiencing a vitamin E deficiency would consume more of a vitamin E-enriched feed than lambs not deficient in vitamin E. Fifty-six Dohne Merino lambs were divided into two groups and fed either a vitamin E-deficient diet over 40 days to induce low plasma vitamin E or a vitamin E-enriched diet to induce high plasma vitamin E. The lambs were then offered a choice of vitamin E-enriched and vitamin E-deficient pellets. For half of the animals, the enriched diet was paired with strawberry flavour and the deficient diet was paired with orange flavour, while the reverse pairings were offered to the others. Lamb preference for the diets was measured daily for the following 15 days. There was a three-way interaction between the high and low vitamin E treatment groups×vitamin E content and type of flavour in the feed×time (days). The lambs preferred pellets flavoured with strawberry but this preference changed to orange flavour in vitamin E-deficient lambs if the orange flavour was paired with high vitamin E. Lambs without a deficiency continued to prefer strawberry-flavoured pellets, regardless of the vitamin E concentrations in the pellets. It is possible that self-learning contributed to the low vitamin E group of lambs changing preference to orange flavour in order to consume more vitamin E, presumably to remediate the deficiency.


Asunto(s)
Alimentación Animal/análisis , Dieta/veterinaria , Preferencias Alimentarias/fisiología , Enfermedades de las Ovejas/fisiopatología , Deficiencia de Vitamina E/veterinaria , Vitamina E/administración & dosificación , Alimentación Animal/normas , Animales , Conducta de Elección/fisiología , Dieta/normas , Femenino , Aromatizantes/farmacología , Distribución Aleatoria , Ovinos , Oveja Doméstica , Gusto/fisiología , Vitamina E/análisis , Deficiencia de Vitamina E/fisiopatología , alfa-Tocoferol/sangre
5.
J Pediatr Urol ; 11(3): 137.e1-5, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25824876

RESUMEN

OBJECTIVE: While there are many options for children with treatment refractory urinary incontinence, there is no single accepted method. This study's aim was to prospectively evaluate the effect of transcutaneous electrical nerve stimulation in children with urinary incontinence resistant to standard medical, urological therapy and/or biofeedback. PATIENTS & METHODS: This study was performed at a university hospital. For inclusion, patients >5 years of age first underwent evaluation with urinary ultrasonography, uroflow-electromyogram and voiding diaries. Treatment with biofeedback, alpha adrenergic blockers, anticholinergics and/or urotherapy was commenced according to uroflow-EMG and voiding diary findings. Patients with partial or no response to this standard therapy were then included in this study, performed between April 2012 and February 2014. Patients with anatomical or neurological causes for urinary incontinence were excluded. TENS was performed on S3 dermatome, every day for 3 months. Each session lasted 20 min with a frequency of 10 Hz and generated pulse of 350 µs. Intensity was determined by the child's sensitivity threshold. Medical treatment and urological therapy was continued during TENS. Uroflow parameters (voiding volume as percentage of expected bladder capacity, Qmax, Qave, flow and voiding time, postvoiding residual urine) and urinary system symptoms (presence of urinary tract infection, frequency, urge incontinence, fractionated voiding and constipation) were compared immediately before commencement and immediately after the completion of 3 months of TENS. RESULTS: Twenty-seven patients were included in this study (4 males, 23 females). Patients' average age was 7.2 years, 11 had overactive bladder and 16 had dysfunctional voiding. Comparison of urinary system symptoms and uroflow parameters before and after TENS are shown in Table. After 3 months of TENS; a statistically significant decrease was observed in the number of patients with frequency, urge incontinence, urinary tract infections and constipation. There was a decrease in the number of patients with fractionated voiding, although this change was not statistically significant. Similarly, for uroflow-EMG parameters; bladder capacity, Qmax, Qave and flow time increased while voiding time and PVR decreased. Changes seen in bladder capacity, Qmax and PVR were statically significant, while other changes were not. Patients' response rates after 3 months of TENS were; complete response in 70.4%, partial response in 22.2% and no response in 7.4%. CONCLUSION: This study has shown that transcutaneous electrical nerve stimulation is a promising treatment option for standard-treatment refractory children with urinary incontinence.


Asunto(s)
Estimulación Eléctrica Transcutánea del Nervio , Incontinencia Urinaria/terapia , Adolescente , Antagonistas Adrenérgicos alfa/uso terapéutico , Biorretroalimentación Psicológica , Niño , Preescolar , Antagonistas Colinérgicos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Retratamiento , Resultado del Tratamiento , Incontinencia Urinaria/diagnóstico , Incontinencia Urinaria/etiología
6.
Int J Lab Hematol ; 30(6): 473-9, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18983299

RESUMEN

In the bone marrow (BM) nucleated differential cell count (NDC), myeloblasts are enumerated as a percentage of total nucleated cells, which are inevitably diluted with peripheral blood nucleated cells (PBNC) during BM aspiration. We propose a partial NDC (PNDC) comprising only immature haemopoietic cells capable of division, i.e. myeloblasts, promyelocytes, myelocytes and erythroblasts. We show that the myeloid : erythroid (M : E) ratio of the PNDC remains approximately constant in progressively dilute aliquots of BM aspirates. We determined the PNDC in 22 healthy subjects and investigated the effect of peripheral blood dilution on disease stratification of 66 BM aspirates with myelodysplastic syndromes (MDS). NDC and PNDC myeloblast counts were compared and the equivalent PNDC myeloblast counts for NDC myeloblast threshold counts of 5, 10 and 20% were derived. Reclassification of MDS samples with the PNDC resulted in a change in disease category in 33.3% of 51 MDS samples with NDC myeloblast counts ranging from 3 to 26%. The PNDC is independent of PBNC dilution and can be determined in dilute BM samples. It alters the disease category in a significant proportion of BM aspirates with MDS and has the potential to better stratify MDS to improve clinical outcomes and treatment.


Asunto(s)
Recuento de Células Sanguíneas/métodos , Células de la Médula Ósea/patología , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/patología , Examen de la Médula Ósea , Núcleo Celular , Células Precursoras de Granulocitos/patología , Humanos
7.
Appl Opt ; 16(4): 944-9, 1977 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20168617

RESUMEN

Image processing has become an invaluable tool in the analysis of solar astronomy and other scientific data. In particular, a number of powerful and intricate image-processing systems have been developed. One such system is the MSFC/S-056 Image Data Processing System (IDAPS), especially designed for the analysis of the Skylab/ATM S-056 X-Ray Telescope experiment data. This paper describes the IDAPS, discusses its unique interactive capabilities, and shows some recent results obtained using the IDAPS.

8.
Blood ; 94(6): 1933-42, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10477722

RESUMEN

The common beta chain (beta(c)) of the granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-5 receptors is the major signaling subunit of these receptors coupling ligand binding to multiple biological activities. It is thought that these multiple functions arise as a consequence of the recruitment of specific signaling molecules to tyrosine-phosphorylated residues in the cytoplasmic domain of beta(c). However, the contribution of serine phosphorylation in beta(c) to the recruitment of signaling molecules is not known. We show here the identification of a phosphoserine motif in the cytoplasmic domain of beta(c) that interacts with the adaptor protein 14-3-3zeta. Coimmunoprecipitation and pull-down experiments with a glutathione S-transferase (GST):14-3-3zeta fusion protein showed that 14-3-3 directly associates with beta(c) but not the GM-CSF receptor alpha chain. C-terminal truncation mutants of beta(c) further showed that a region between amino acids 544 and 626 in beta(c) was required for its association with 14-3-3zeta. This region contains the sequence (582)HSRSLP(587), which closely resembles the RSXSXP (where S is phosphorylated) consensus 14-3-3 binding site identified in a number of signaling molecules, including Raf-1. Significantly, substitution of (582)HSRSLP(587) for EFAAAA completely abolished interaction of beta(c) with GST-14-3-3zeta. Furthermore, the interaction of beta(c) with GST-14-3-3 was greatly reduced in the presence of a peptide containing the 14-3-3 binding site, but only when (585)Ser was phosphorylated. Direct binding experiments showed that the peptide containing phosphorylated (585)Ser bound 14-3-3zeta with an affinity of 150 nmol/L. To study the regulation of (585)S phosphorylation in vivo, we raised antibodies that specifically recognized (585)Ser-phosphorylated beta(c). Using these antibodies, we showed that GM-CSF stimulation strongly upregulated (585)Ser phosphorylation in M1 myeloid leukemic cells. The proximity of the SHC-binding site ((577)Tyr) to the 14-3-3-binding site ((582)HSRSLP(587)) and their conservation between mouse, rat, and human beta(c) but not in other cytokine receptors suggest that they form a distinct motif that may subserve specialized functions associated with the GM-CSF, IL-3, and IL-5 receptors.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Fosfoserina/metabolismo , Proteínas/química , Proteínas/metabolismo , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Receptores de Interleucina-3/metabolismo , Receptores de Interleucina/metabolismo , Tirosina 3-Monooxigenasa , Proteínas 14-3-3 , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Sitios de Unión , Humanos , Cinética , Sustancias Macromoleculares , Ratones , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Fosforilación , Mutación Puntual , Ratas , Receptores de Factor Estimulante de Colonias de Granulocitos y Macrófagos/química , Receptores de Interleucina/química , Receptores de Interleucina-3/química , Receptores de Interleucina-5 , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido
10.
Br Med J ; 1(5537): 437, 1967 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-6017513
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