Gypsum labelled with tritiated water as a marker for estimating supplement intake by individual sheep fed in groups

1984 ◽  
Vol 24 (127) ◽  
pp. 484 ◽  
Author(s):  
H Dove
Keyword(s):  
Specific Activity ◽  
Tritiated Water ◽  
Rapeseed Meal ◽  
Mean Difference ◽  
Sunflower Meal ◽  
Measurement Variability ◽  
Plaster Of Paris ◽  
The Mean ◽  
Stocking Rates ◽  
Supplement Intake

Three experiments were conducted to evaluate gypsum, labelled in its water of crystallization with tritiated water (TOH), as a marker substance for estimating the intake of solid supplements by grazing ruminants. The TOH-gypsum was prepared by mixing plaster of Paris with TOH and was then incorporated into pelleted supplements of sunflower meal (SFM) or rapeseed meal (RSM). All gypsum specific activity could be recovered by 48 h extraction with 0.02 M NaEDTA, but not 48 h extraction with water. When known levels of labelled SFM were fed to housed lambs, the mean difference between known and estimated intake was 4% or 28 g/d. The slope of the regression relating these intakes was not significantly different from 1 0. In the second experiment, the same lambs were offered labelled SFM outdoors, from communal troughs, at daily rates of 400 or 1000 g/head. In the first group, mean intake estimated from the marker was 2% or 8 g/d different from that estimated from trough measurements. In the second group, spillage and trampling of supplements was observed, and intake estimated using the marker was only 88% of that estimated from trough measurement. Variability between animals in intake was high and ranged from 336 to 1302 g/d over the two feeding levels. Accuracy of the marker method was confirmed in a third study with Merinos grazing wheat stubbles at two stocking rates, supplemented with 325 g/d of SFM or RSM. Those offered RSM ate very little, but intake was accurately detected down to levels of less than 30 g/d. The results are discussed in relation to possible sources of error, particularly day-to-day variations in individual intake.

Estimation of water content by tritium dilution of animals subjected to rapid live-weight changes

1969 ◽  
Vol 72 (1) ◽  
pp. 31-40 ◽  
Author(s):  
W. R. McManus ◽  
R. K. Prichard ◽  
Carolyn Baker ◽  
M. V. Petruchenia
Keyword(s):  
Body Weight ◽  
Water Content ◽  
Total Body Water ◽  
Compensatory Growth ◽  
Specific Activity ◽  
Tritiated Water ◽  
Body Water ◽  
Under Nutrition ◽  
The Mean ◽  
Total Body

SUMMARYThe use of tritiated water to estimate total body-water content of animals experiencing recovery from under-nutrition was studied.The time for equilibration of tritiated water (TOH), given intraperitoneally, with total body water (TBW) was determined in rabbits and in rats. As judged by the specific activity of blood water, equilibration had occurred by 76–125 min in the rabbit and did not appear to be affected by the plane of nutrition. However, between slaughter groups the specific activity of water obtained from the liver 180 min after injection of TOH was significantly different from the specific activity of water simultaneously obtained from the blood plasma. It is concluded that the liver is not a suitable tissue to use for testing achievement of equilibration.As judged by the specific activity of blood water compared to that of water from the whole body macerate, equilibration in mature rats either in stable body condition or undergoing rapid compensatory growth occurred in less than 60 min.A trial comparing TOH-space (corrected by 3% body weight) and actual TBW (by desiccation) was conducted on thirty rabbits which experienced under-nutrition followed by compensatory growth.Prior to under-nutrition the agreement between actual and estimated TBW was satisfactory and within 2·3%. During compensatory growth the agreement was poor— the TOH values over-estimating actual TBW by about 12%.A trial with mature rats confirmed the findings with rabbits. For rats in stable body weight the mean estimated TOH-space for fourteen animals was within 1·2% of the actual TBW. For fourteen rats undergoing compensatory growth the mean estimated TOH-space (corrected by 3% body weight) overestimated actual TBW by 6·2%.

Responses to supplements by weaned lambs grazing mature pasture or eating hay in yards

1985 ◽  
Vol 25 (2) ◽  
pp. 289 ◽  
Author(s):  
M Freer ◽  
H Dove ◽  
A Axelsen ◽  
JR Donnelly ◽  
GT McKinney
Keyword(s):  
Substitution Rate ◽  
Poor Performance ◽  
Sunflower Meal ◽  
Wool Production ◽  
Grazed Pasture ◽  
Significant Difference ◽  
Ad Libitum ◽  
Stocking Rates ◽  
Daily Gain ◽  
Supplement Intake

Weaned crossbred lambs grazing mature pasture in summer at stocking rates of 14, 28 or 42 lambs/ha were supplemented for 60 days with 0, 400, 600 or 800 g/day of either sunflower meal or a 1:1 mixture of sunflower meal and oats. Mean daily gains in fasted weight without and with supplement were - 51 and 62 g, respectively, with no significant difference between the three feeding levels. Greasy wool production increased from 4.7 g/day without supplement to 9.9 g/day at the 600 or 800 g level but the composition of the supplement had no effect. Stocking rate had no effect on animal performance. It was estimated that pasture intake increased slightly with the first 400 g of supplement but fell sharply as the level increased further, with a substitution rate of 1.3. In two experiments, yarded lambs were offered oaten or lucerne hay ad libitum and mixtures of sunflower meal and oats at levels from 400 g/day to ad libitum. Mean daily gain in fasted weight increased from about 140 to about 190 g/day over this range of supplementation and greasy wool production from about 9 to about 10 g/day. In one experiment weight gain and wool production were significantly lower with a 1:6 mixture of sunflower meal and oats than with a 1:2 mixture and the same trend was shown in the other experiment. Measurements of intake showed that the substitution rate for both types of hay was only about 0.5. Comparisons of the animals' estimated requirements and intake in all three experiments indicated that the relatively poor performance of grazing animals was due to the very high substitution rate for grazed pasture at levels of supplement intake above 400 g/day.

Rape and sunflower seed meals as supplements for sheep grazing cereal stubbles

1987 ◽  
Vol 27 (4) ◽  
pp. 513 ◽  
Author(s):  
JB Coombe ◽  
A Axelsen ◽  
H Dove
Keyword(s):  
Rapeseed Meal ◽  
High Variability ◽  
Free Access ◽  
Sheep Grazing ◽  
Sunflower Meal ◽  
Merino Sheep ◽  
Wool Growth ◽  
Wheat Stubble ◽  
Daily Intakes ◽  
Stocking Rates

In 2 experiments, Merino sheep aged about 18 months grazed cereal stubbles for 12 weeks and were either: (i) given no supplement; (ii) given free access to blocks containing 30% urea; or received daily about 300 g DM sheep-1 of (iii) rapeseed meal (RSM); (iv) formaldehyde-treated RSM (FRSM); (v) sunflower meal (SFM); or (vi) formaldehyde-treated SFM (FSFM). In experiment 1, wethers grazed a barley stubble at stocking rates (SR) of 18 and 36 sheep ha-1, and in experiment 2, mixed flocks of wethers and ewes grazed wheat stubble at 10 and 20 sheep ha-1. Mean daily intakes of urea were about 8.5 and 11.5 g sheep-1 for experiments 1 and 2 respectively. Both forms of SFM were readily eaten throughout, but in both experiments, intakes of RSM and FRSM were low and were characterised by high variability from day to day, and among individual sheep within groups. In both experiments, all sheep gained some weight during the first 2-3 weeks; thereafter control and urea fed sheep lost weight at mean rates varying from about 96 to 180 g day-1 depending on SR. Feeding SFM or FSFM reduced this loss to about 20 g day-1 at SR of 10-20 ha-1, and to 60 g day-1 at a SR of 36 ha-1, while losses were intermediate in sheep fed RSM or FRSM. In experiment 1, daily wool growth rates varied from about 5.5 g clean dry wool (CDW) sheep-1 for control and urea-fed sheep to about 11 g CDW sheep-1 for sheep fed SFM and FSFM; respective daily rates in experiment 2 were 3.6 and 8.2 g CDW sheep-1. Wool growth of sheep fed RSM and FRSM was intermediate in both experiments. When ewes were mated on high-quality feed after grazing stubbles, conception was delayed for about 14 days in a high proportion (about 40%) of those ewes that had lost considerable weight during stubble grazing. This effect was overcome by feeding daily 300 g DM sheep-1 of SFM for 7 days prior to and during mating. Delayed conception extended the lambing period. although final numbers of lambs born were not different among groups.

Comparison of rapeseed meal, sunflower and soyabean meals as protein sources in concentrates for milking cows

1989 ◽  
Vol 1989 ◽  
pp. 142-142
Author(s):  
Isobel C. Vincent ◽  
R. Hill ◽  
R.C. Campling
Keyword(s):  
Crude Protein ◽  
Block Design ◽  
Control Diet ◽  
Rapeseed Meal ◽  
Major Protein ◽  
Protein Supplement ◽  
Sunflower Meal ◽  
Soyabean Meal ◽  
The Mean ◽  
Friesian Cattle

A compound feed that is designed to be given in equal amounts with cereals for milk production would contain about 30% crude protein, and if rapeseed meal were the major high protein supplement to be used along with cereal, about 60% would need to be included. No observations have been reported in which this high proportion of rapeseed meal has been used and the experiment described was planned to provide this information, using low glucosinolate rapeseed meal. The control diet contained soyabean meal in place of rapeseed meal, and a third compound was used containing sunflower meal seed as the major protein supplement.Thirty-nine Friesian cattle were used in a randomised block design: the three treatments, compounds containing low glucosinolate rapeseed meal, sunflower seed meal and soyabean meal, were applied for 16 weeks. There were 21 cows and 18 heifers, the mean days in milk at the start of the experiment was 62 days and the mean yield over the previous two weeks was 26.9 kg.

scholarly journals Do we need to improve the reporting of evidence in tendinopathy management? A critical appraisal of systematic reviews with recommendations on strength of evidence assessment

2021 ◽  
Vol 7 (1) ◽  
pp. e000920
Author(s):  
Dimitris Challoumas ◽  
Neal L Millar
Keyword(s):  
Systematic Reviews ◽  
Assessment Tool ◽  
Data Extraction ◽  
Cochrane Collaboration ◽  
Mean Difference ◽  
Strength Of Evidence ◽  
The Mean ◽  
Randomised Controlled ◽  
Meta Analyses ◽  
The Cochrane Collaboration

ObjectiveTo critically appraise the quality of published systematic reviews (SRs) of randomised controlled trials (RCTs) in tendinopathy with regard to handling and reporting of results with special emphasis on strength of evidence assessment.Data sourcesMedline from inception to June 2020.Study eligibilityAll SRs of RCTs assessing the effectiveness of any intervention(s) on any location of tendinopathy.Data extraction and synthesisIncluded SRs were appraised with the use of a 12-item tool devised by the authors arising from the Preferred Reporting Items in Systematic Reviews and Meta-Analyses statement and other relevant guidance. Subgroup analyses were performed based on impact factor (IF) of publishing journals and date of publication.ResultsA total of 57 SRs were included published in 38 journals between 2006 and 2020. The most commonly used risk-of-bias (RoB) assessment tool and strength of evidence assessment tool were the Cochrane Collaboration RoB tool and the Cochrane Collaboration Back Review Group tool, respectively. The mean score on the appraisal tool was 46.5% (range 0%–100%). SRs published in higher IF journals (>4.7) were associated with a higher mean score than those in lower IF journals (mean difference 26.4%±8.8%, p=0.004). The mean score of the 10 most recently published SRs was similar to that of the first 10 published SRs (mean difference 8.3%±13.7%, p=0.54). Only 23 SRs (40%) used the results of their RoB assessment in data synthesis and more than half (n=30; 50%) did not assess the strength of evidence of their results. Only 12 SRs (21%) assessed their strength of evidence appropriately.ConclusionsIn light of the poor presentation of evidence identified by our review, we provide recommendations to increase transparency and reproducibility in future SRs.

scholarly journals The Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) Study—Defining a Threshold for Non-Cycloplegic Myopia Prevalence in Children

2021 ◽  
Vol 10 (6) ◽  
pp. 1215
Author(s):  
Aparna Gopalakrishnan ◽  
Jameel Rizwana Hussaindeen ◽  
Viswanathan Sivaraman ◽  
Meenakshi Swaminathan ◽  
Yee Ling Wong ◽  
...  
Keyword(s):  
Open Field ◽  
Tamil Nadu ◽  
Mean Difference ◽  
School Vision ◽  
Elite School ◽  
Prevalence Estimates ◽  
The Mean ◽  
Clinically Significant ◽  
Set Up ◽  
Definition Of

The aim of this study was to investigate the agreement between cycloplegic and non-cycloplegic autorefraction with an open-field auto refractor in a school vision screening set up, and to define a threshold for myopia that agrees with the standard cycloplegic refraction threshold. The study was conducted as part of the Sankara Nethralaya Tamil Nadu Essilor Myopia (STEM) study, which investigated the prevalence, incidence, and risk factors for myopia among children in South India. Children from two schools aged 5 to 15 years, with no ocular abnormalities and whose parents gave informed consent for cycloplegic refraction were included in the study. All the children underwent visual acuity assessment (Pocket Vision Screener, Elite school of Optometry, India), followed by non-cycloplegic and cycloplegic (1% tropicamide) open-field autorefraction (Grand Seiko, WAM-5500). A total of 387 children were included in the study, of whom 201 were boys. The mean (SD) age of the children was 12.2 (±2.1) years. Overall, the mean difference between cycloplegic and non-cycloplegic spherical equivalent (SE) open-field autorefraction measures was 0.34 D (limits of agreement (LOA), 1.06 D to −0.38 D). For myopes, the mean difference between cycloplegic and non-cycloplegic SE was 0.13 D (LOA, 0.63D to −0.36D). The prevalence of myopia was 12% (95% CI, 8% to 15%) using the threshold of cycloplegic SE ≤ −0.50 D, and was 14% (95% CI, 11% to 17%) with SE ≤ −0.50 D using non-cycloplegic refraction. When myopia was defined as SE of ≤−0.75 D under non-cycloplegic conditions, there was no difference between cycloplegic and non-cycloplegic open-field autorefraction prevalence estimates (12%; 95% CI, 8% to 15%; p = 1.00). Overall, non-cycloplegic refraction underestimates hyperopia and overestimates myopia; but for subjects with myopia, this difference is minimal and not clinically significant. A threshold of SE ≤ −0.75 D agrees well for the estimation of myopia prevalence among children when using non-cycloplegic refraction and is comparable with the standard definition of cycloplegic myopic refraction of SE ≤ −0.50 D.

scholarly journals Estimates of the mean difference in orthopaedic randomized trials: obligatory yet obscure

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lauri Raittio ◽  
Antti Launonen ◽  
Ville M. Mattila ◽  
Aleksi Reito
Keyword(s):  
Primary Outcome ◽  
Outcome Measure ◽  
Patient Reported Outcome ◽  
Ceiling Effect ◽  
Mean Difference ◽  
Discussion Section ◽  
Power Calculations ◽  
Randomized Controlled ◽  
Patient Reported ◽  
The Mean

Abstract Background Randomized controlled trials in orthopaedics are powered to mainly find large effect sizes. A possible discrepancy between the estimated and the real mean difference is a challenge for statistical inference based on p-values. We explored the justifications of the mean difference estimates used in power calculations. The assessment of distribution of observations in the primary outcome and the possibility of ceiling effects were also assessed. Methods Systematic review of the randomized controlled trials with power calculations in eight clinical orthopaedic journals published between 2016 and 2019. Trials with one continuous primary outcome and 1:1 allocation were eligible. Rationales and references for the mean difference estimate were recorded from the Methods sections. The possibility of ceiling effect was addressed by the assessment of the weighted mean and standard deviation of the primary outcome and its elaboration in the Discussion section of each RCT where available. Results 264 trials were included in this study. Of these, 108 (41 %) trials provided some rationale or reference for the mean difference estimate. The most common rationales or references for the estimate of mean difference were minimal clinical important difference (16 %), observational studies on the same subject (8 %) and the ‘clinical relevance’ of the authors (6 %). In a third of the trials, the weighted mean plus 1 standard deviation of the primary outcome reached over the best value in the patient-reported outcome measure scale, indicating the possibility of ceiling effect in the outcome. Conclusions The chosen mean difference estimates in power calculations are rarely properly justified in orthopaedic trials. In general, trials with a patient-reported outcome measure as the primary outcome do not assess or report the possibility of the ceiling effect in the primary outcome or elaborate further in the Discussion section.

scholarly journals Corneal Biomechanical Parameters and Central Corneal Thickness in Glaucoma Patients, Glaucoma Suspects, and a Healthy Population

2021 ◽  
Vol 10 (12) ◽  
pp. 2637
Author(s):  
Mª. Ángeles del Buey-Sayas ◽  
Elena Lanchares-Sancho ◽  
Pilar Campins-Falcó ◽  
María Dolores Pinazo-Durán ◽  
Cristina Peris-Martínez
Keyword(s):  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Mean Difference ◽  
The Other ◽  
Control Group ◽  
Healthy Population ◽  
Diagnostic Categories ◽  
Significant Difference ◽  
Biomechanical Parameters ◽  
The Mean

Purpose: To evaluate and compare corneal hysteresis (CH), corneal resistance factor (CRF), and central corneal thickness (CCT), measurements were taken between a healthy population (controls), patients diagnosed with glaucoma (DG), and glaucoma suspect patients due to ocular hypertension (OHT), family history of glaucoma (FHG), or glaucoma-like optic discs (GLD). Additionally, Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated IOP (IOPcc) were compared between the different groups of patients. Methods: In this prospective analytical-observational study, a total of 1065 patients (one eye of each) were recruited to undergo Ocular Response Analyzer (ORA) testing, ultrasound pachymetry, and clinical examination. Corneal biomechanical parameters (CH, CRF), CCT, IOPg, and IOPcc were measured in the control group (n = 574) and the other groups: DG (n = 147), FHG (n = 78), GLD (n = 90), and OHT (n = 176). We performed a variance analysis (ANOVA) for all the dependent variables according to the different diagnostic categories with multiple comparisons to identify the differences between the diagnostic categories, deeming p < 0.05 as statistically significant. Results: The mean CH in the DG group (9.69 mmHg) was significantly lower compared to controls (10.75 mmHg; mean difference 1.05, p < 0.001), FHG (10.70 mmHg; mean difference 1.00, p < 0.05), GLD (10.63 mmHg; mean difference 0.93, p < 0.05) and OHT (10.54 mmHg; mean difference 0.84, p < 0.05). No glaucoma suspects (FHG, GLD, OHT groups) presented significant differences between themselves and the control group (p = 1.00). No statistically significant differences were found in the mean CRF between DG (11.18 mmHg) and the control group (10.75 mmHg; mean difference 0.42, p = 0.40). The FHG and OHT groups showed significantly higher mean CRF values (12.32 and 12.41 mmHg, respectively) than the DG group (11.18 mmHg), with mean differences of 1.13 (p < 0.05) and 1.22 (p < 0.001), respectively. No statistically significant differences were found in CCT in the analysis between DG (562 μ) and the other groups (control = 556 μ, FHG = 576 μ, GLD = 569 μ, OHT = 570 μ). The means of IOPg and IOPcc values were higher in the DG patient and suspect groups than in the control group, with statistically significant differences in all groups (p < 0.001). Conclusion: This study presents corneal biomechanical values (CH, CRF), CCT, IOPg, and IOPcc for diagnosed glaucoma patients, three suspected glaucoma groups, and a healthy population, using the ORA. Mean CH values were markedly lower in the DG group (diagnosed with glaucoma damage) compared to the other groups. No significant difference was found in CCT between the DG and control groups. Unexpectedly, CRF showed higher values in all groups than in the control group, but the difference was only statistically significant in the suspect groups (FHG, GLD, and OHT), not in the DG group.

scholarly journals Plasma mineral (selenium, zinc or copper) concentrations in the general pregnant population, adjusted for supplement intake, in relation to thyroid function

2020 ◽  
Vol 125 (1) ◽  
pp. 71-78
Author(s):  
Victor Pop ◽  
Johannes Krabbe ◽  
Wolfgang Maret ◽  
Margaret Rayman
Keyword(s):  
Thyroid Function ◽  
Reference Range ◽  
First Trimester ◽  
Future Research ◽  
Thyroid Peroxidase ◽  
Reference Ranges ◽  
Lower Plasma ◽  
The Mean ◽  
The Impact ◽  
Supplement Intake

AbstractThe present study reports on first-trimester reference ranges of plasma mineral Se/Zn/Cu concentration in relation to free thyroxine (FT4), thyrotropin (TSH) and thyroid peroxidase antibodies (TPO-Ab), assessed at 12 weeks’ gestation in 2041 pregnant women, including 544 women not taking supplements containing Se/Zn/Cu. The reference range (2·5th–97·5th percentiles) in these 544 women was 0·72–1·25 µmol/l for Se, 17·15–35·98 µmol/l for Cu and 9·57–16·41 µmol/l for Zn. These women had significantly lower mean plasma Se concentration (0·94 (sd 0·12) µmol/l) than those (n 1479) taking Se/Zn/Cu supplements (1·03 (sd 0·14) µmol/l; P < 0·001), while the mean Cu (26·25 µmol/l) and Zn (12·55 µmol/l) concentrations were almost identical in these sub-groups. Women with hypothyroxinaemia (FT4 below reference range with normal TSH) had significantly lower plasma Zn concentrations than euthyroid women. After adjusting for covariates including supplement intake, plasma Se (negatively), Zn and Cu (positively) concentrations were significantly related to logFT4; Se and Cu (but not Zn) were positively and significantly related to logTSH. Women taking additional Se/Zn/Cu supplements were 1·46 (95 % CI 1·09, 2·04) times less likely to have elevated titres of TPO-Ab at 12 weeks of gestation. We conclude that first-trimester Se reference ranges are influenced by Se-supplement intake, while Cu and Zn ranges are not. Plasma mineral Se/Zn/Cu concentrations are associated with thyroid FT4 and TSH concentrations. Se/Zn/Cu supplement intake affects TPO-Ab status. Future research should focus on the impact of trace mineral status during gestation on thyroid function.

Responses to supplements by weaned lambs when grazing mature pasture or eating hay cut from the same pasture

1988 ◽  
Vol 110 (3) ◽  
pp. 661-667 ◽  
Author(s):  
M. Freer ◽  
H. Dove ◽  
A. Axelsen ◽  
J. R. Donnelly
Keyword(s):  
Weight Gain ◽  
Coefficient Of Variation ◽  
Substitution Rate ◽  
Eating Behaviour ◽  
Sunflower Meal ◽  
Total Intake ◽  
Grazed Pasture ◽  
Ad Libitum ◽  
Four Levels ◽  
Supplement Intake

SummaryWeaned cross-bred lambs either grazed mature pasture or were confined to yards where they were offered material cut from ungrazed areas of the same pasture. A 1:2 mixture (on an air-dry basis) of sunflower meal and oat grain was offered for 81 days at 0, 200, 400 or 600 g/head or ad libitum. Individual estimates of intake of pasture and supplement by grazing sheep at four levels of supplementation were made on four adjacent plots.Weight gain increased from –30 to 178 g/day in the grazing animals as supplement intake increased up to 1030 g D.M./day and from –25 to 142 g/day in the yarded animals as supplement intake increased to 1076 g D.M./day. Growth of greasy wool increased from 4·5 to 11·7 g/day for grazing animals and from 4·5 to 10·2 g/day for those kept in yards.At levels of supplement intake below 400 g D.M./day, the intake of grazed pasture increased by up to 58% compared with unsupplemented animals. However, when the intake of supplement was increased to about 650 g D.M./day, pasture intake fell, with an estimated substitution rate of 1·1 g D.M. pasture per g D.M. supplement. At all levels of supplementation, the intake of hay by the yarded lambs was less than half the intake of herbage in the field. However, at levels of supplement intake between 300 and 500 g D.M./day, the substitution rate was similar to that measured in the grazing animals, suggesting that this is an attribute of roughage quality, rather than differential eating behaviour between grazing and yarded animals.The wastage, w (g D.M./day), of supplement was linearly related to the amount offered, s (g D.M./day), by the equationw = 0·263s − 38·8; R2 = 0·89Variability in supplement intake between individual grazing lambs was not affected by the level of supplementation but the coefficient of variation of supplement intake was considerably greater than that of the intake of unsupplemented pasture. Variability in the intake of pasture increased with the level of supplementation but variability in the total intake of food was similar at each level of supplement, indicating some degree of individual compensation in the intake of the two components.

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