A comparison of the effects of carbon dioxide and medical air for abdominal insufflation on respiratory parameters in xylazine-sedated sheep undergoing laparoscopic artificial insemination     

JD Haan  BL Hay Kraus  SR Sathe 《New Zealand veterinary journal》2018,66(4):167-171

AIMS: To determine if abdominal insufflation with medical air will improve oxygenation and ventilation parameters when compared to insufflation with CO₂ in xylazine-sedated sheep undergoing laparoscopic artificial insemination (AI).

METHODS: Forty-seven sheep underwent oestrus synchronisation and were fasted for 24 hours prior to laparoscopic AI. Each animal was randomised to receive either CO₂ or medical air for abdominal insufflation. An auricular arterial catheter was placed and utilised for serial blood sampling. Respiratory rates (RR) and arterial blood samples were collected at baseline, after xylazine (0.1?mg/kg I/V) sedation, 2 minutes after Trendelenburg positioning, 5 minutes after abdominal insufflation, and 10 minutes after being returned to a standing position. Blood samples were collected in heparinised syringes, stored on ice, and analysed for arterial pH, partial pressure of arterial O₂ (PaO₂), and CO₂ (PaCO₂). The number of ewes conceiving to AI was also determined.

RESULTS: Repeated measures ANOVA demonstrated temporal effects on RR, PaO₂, PaCO₂ and arterial pH during the laparoscopic AI procedure (p<0.001), but no difference between insufflation groups (p>0.01). No sheep experienced hypercapnia (PaCO₂>50?mmHg) or acidaemia (pH<7.35). Hypoxaemia (PaO₂<70?mmHg) was diagnosed during the procedure in 14/22 (64%) ewes in the CO₂ group compared with 8/23 (35%) ewes in the medical air group (p=0.053). Overall, 15/20 (75%) ewes in the CO₂ group conceived to AI compared with 16/22 (72.7%) in the medical air group (p=0.867).

CONCLUSIONS AND CLINICAL RELEVANCE: There were no statistical or clinical differences in RR, PaO₂, PaCO₂, pH, or conception to AI when comparing the effects of CO₂ and medical air as abdominal insufflation gases. None of the sheep experienced hypercapnia or acidaemic, yet 42% (19/45) of sheep developed clinical hypoxaemia, with a higher percentage of ewes in the CO₂ group developing hypoxaemia than in the medical air group. Based on the overall analysis, medical air could be utilised as a comparable alternative for abdominal insufflation during laparoscopic AI procedures.  相似文献   

Ergovaline does not alter the severity of ryegrass staggers induced by lolitrem B     

SC Finch  JB Vlaming  BL Sutherland  C van Koten  WJ Mace  LR Fletcher 《New Zealand veterinary journal》2018,66(2):93-97

AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline.

METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.

RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).

CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.  相似文献   

Greenhouse gas mitigation potential of agricultural land in Great Britain     

N. Fitton  C. P. Ejerenwa  A. Bhogal  P. Edgington  H. Black  A. Lilly  D. Barraclough  F. Worrall  J. Hillier  P. Smith 《Soil Use and Management》2011,27(4):491-501

The aim of this paper is to assess the greenhouse gas (GHG) mitigation potential of croplands and grasslands in Great Britain under different management practices. We consider the feasible land management options for grass and cropland using county level land‐use data with estimates of per‐area mitigation potential for individual and total GHGs, to identify the land management options with the greatest cost‐effective mitigation potential. We show that for grasslands, uncertainties still remain on the mitigation potential because of their climatic sensitivity and also their less intensive management. For croplands in Great Britain, the technical mean GHG mitigation potentials for all cropland management practices range from 17 Mt CO₂‐eq. per 20 yr to 39 Mt CO₂‐eq. per 20 yr. There are significant regional variation in all cases, with the greatest potentials in England, negligible potential in Wales and intermediate potential in Scotland, with country differences largely driven by the areas of cropland and grassland in each country. Practices such as agronomic improvement and nutrient management are the most promising options because of their impact on N₂O emissions and also their larger potential at low cost. In terms of annual emissions from agriculture, calculated mitigation potentials are small, where the technical mitigation potential of agronomy and nutrient management strategies are ca. 4.5 and 3.8%, respectively (agricultural emissions account for ca. 9% or 47.7 Mt CO₂‐eq., of total Great Britain GHG emissions, Department of Energy and Climate Change, UK). However when compared with the land use, land‐use change and forestry sector (LULUCF) emissions, nutrient management would reduce further emission reductions by approximately half of the 2005 LULUCF sink (i.e. ?1.6 Mt CO₂‐eq. per year).  相似文献   

Carcinogen in rock fern (Chielanthes sieberi) from New Zealand and Australia     

BL SMITH  PP EMBLING  DR LAUREN  MP AGNEW  AD ROSS  PL GREENTREE 《Australian veterinary journal》1989,66(7):230-231

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Comparison between the seminal and nodal root systems of winter wheat in their activity for N and K uptake     

H. Kuhlmann  P. B. Barraclough 《植物养料与土壤学杂志》1987,150(1):24-30

The activity of seminal and nodal root systems of winter wheat (cv. Avalon) in taking up NO₃^? and K⁺ has been measured in solution culture using a split root technique. Plants in the tillering phase of growth (36 days old) were used for the experiment which lasted 20 days. During this time plant dry weights increased by a factor of 20, whilst root: shoot ratios and nutrient compositions remained constant. Inflows (uptake rate per unit root length) were 2–6 times higher for the nodal roots than for the seminal roots, with values varying between 1 and 9 pmol cm^?1 s^?1 for N and between 0.5 and 4 pmol cm^?1 s^?1 for K. When uptake was expressed on the basis of unit fresh weight of roots, values ranged from 1 to 2.3 pmol mg^?1 s^?1 for N and from 0.4 to 1.0 pmol mg^?1 s^?1 for K, and there were only very small differences in uptake efficiency between the nodal and seminal roots. Uptake rate per unit root decreased with plant age. This was caused by a decline in shoot demand due to the reduction of the relative growth rate. When either the nodal or seminal root system alone was supplied with nutrients, uptake rate per unit root increased and nutrient uptake per plant reached 72–92% of the control.  相似文献   

Antigenic relationship of the picorna-like virus of larval barramundi, Lates calcarifer Bloch to the nodavirus of larval striped jack, Pseudocaranx dentex (Bloch & Schneider)     

BL MUNDAY  T NAKAI  HD NGUYEN 《Australian veterinary journal》1994,71(11):384-385

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2.7 Cabbage Root Fly on Brussels sprouts in Warwickshire, 1963     

K. J. Coghill  Ruth M.  Barraclough 《Plant pathology》1965,14(S1):10-11

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Unrecognized diversity in New Guinean crayfish species (Decapoda,Parastacidae): The evidence from molecular data          下载免费PDF全文

Martin BLÁHA  Jiří PATOKA  Pavel KOZÁK  Antonín KOUBA 《Integrative zoology》2016,11(6):457-468

The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders.  相似文献   

Soil N dynamics in a natural calcareous grassland under a changing climate   总被引：5，自引：0，他引：5  

N. Jamieson  D. Barraclough  M. Unkovich  R. Monaghan 《Biology and Fertility of Soils》1998,27(3):267-273

 This paper reports the results from a medium-term field scale investigation into the effects of simulated climate change on soil N mineralisation in a semi-natural calcareous grassland in southern England. The experiment utilised soil warming cables, automatic rainshelters and a watering system to examine two climate change scenarios: warmer winters with summer drought and warmer winters with enhanced summer rainfall. Gross N mineralisation rates in treated plots were determined, using ¹⁵N pool dilution techniques, at 6-weekly intervals over a 3-year period. Results from control plots showed a strong seasonality of mineralisation with highest rates in autumn and winter and lowest rates in summer. They suggest that water availability is the main constraint on microbial processes and plant growth. Unexpectedly, additional summer rainfall had no direct effect on N mineralisation at the time of application (summer). The treatment did, however, significantly (<0.05%) reduce rates in subsequent autumn and winter months. In contrast, summer drought significantly increased N mineralisation rates in autumn and winter. Winter warming similarly had no direct effect on N mineralisation in winter but decreased rates in spring. We hypothesise that the observed treatment effects result from changes in organic C and N input, in plant litter, resulting from the direct impact of climatic manipulation on perennial plant growth, death and senescence. This paper compares and contrasts the response to climate manipulation in the grassland system with results from other ecosystem types such as northern forests. Received: 1 December 1997  相似文献   

Major compositional units of the moon: lunar prospector thermal and fast neutrons   总被引：2，自引：0，他引：2  

WC Feldman  BL Barraclough  S Maurice  RC Elphic  DJ Lawrence  DR Thomsen  AB Binder 《Science (New York, N.Y.)》1998,281(5382):1489-1493

Global maps of thermal and fast neutron fluxes from the moon suggest three end-member compositional units. A high thermal and low fast neutron flux unit correlates with the lunar highlands and is consistent with feldspathic rocks. The South Pole-Aitken basin and a strip that surrounds the nearside maria have intermediate thermal and fast neutron flux levels, consistent with more mafic rocks. There appears to be a smooth transition between the most mafic and feldspathic compositions, which correspond to low and high surface altitudes, respectively. The maria show low thermal and high fast neutron fluxes, consistent with basaltic rocks.  相似文献