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Number of results: 1457
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Abstract

Material of tesseraspids (Tesseraspidiformes) is reported from the uppermost Severnaya Zemlya Formation (Lochkovian, Lower Devonian) of the Severnaya Zemlya archipelago, in the Russian Arctic, where it is associated with other vertebrate remains, including corvaspids, acanthodians, and large but rare specimens of osteostracans. The tesseraspid material is not abundant, and most often preserved as a “patchwork” of bony platelets (tesserae), except for a few partly articulated specimens. We redescribe the holotype of Tesseraspis mosaica Karatajūtė-Talimaa, 1983, whose head carapace is preserved as a flattened tube of adjacent tesserae. This material is compared to the already published tesseraspid taxa, i.e., T. tessellata Wills, 1935, T. toombsi Tarlo, 1964, T. mutabilis (Brotzen, 1934), T. oervigi Tarlo, 1964 emend. Dineley and Loeffler, 1976, T. denisoni Tarlo, 1964, and T. talimaae Tarlo, 1965. All species are based upon rare and incomplete material, as no head carapaces associated with trunk and tail are known, and so, the intraspecific variability is also unknown. Distinction between “species” is based on the detail of the superficial sculpture of the tesserae of the head carapaces, which is unsatisfactory. It is concluded that only four of the nominal species can be retained. A review of all other known tessellated pteraspidomorphs indicates that our knowledge of tessellated heterostracans is currently insufficient to support a meaningful classification.
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Abstract

In general, Antarctic marine bacteria are small, with biovolumes ranging from 0.139 to 0.204 μm-3 cell-1, but their total biomass in seawater is considerable due to relatively high numbers that approximate to 1020 cells km-3. Bacterial biomass becomes more concentrated closer to land. Our multi-year Antarctic studies demonstrated an average total bacterial biomass of 504 tons in Admirality Bay (24 km3) or 21 tons per 1 km3, versus 6.4 tons per 1 km3 in the open ocean. Strikingly, bacterial biomass reached 330 tons per 1 km3 of seawater at the sea-ice edge, as sampled in Goulden Cove in Admiralty Bay. Bacterial biomass in Admirality Bay, which we believe can be enriched by halotolerant and thermotolerant fresh water bacteria from glacial streams, is equal to or even exceeds that of the standing stock of krill (100-630 tons per bay) or other major living components, including phytoplankton (657 tons), flagellates (591 tons), and ciliates (412 tons). However, the bacterial biomass is exceeded by several orders of magnitude by non-living organic matter, which constitutes the basic bacterial carbon source. Factors regulating high bacterial abundance in the vicinity of land are discussed.
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Abstract

Total count (TC) of bacteria in drifting annual pack-ice in austral spring fluctuated between 2.8-106 and 2,09-109 dm3. TC of bacteria was lowest in the upper layer of a large pack-ice fragment, emersed above water surface and almost completely free of diatoms; it was comparable to TC of bacteria in surrounding sea water, which was very low at this time (1,92- 106 — 5.8-106 dm -3). TC of bacteria increased in the deeper layers of pack-ice, attaining a maximum in the middle layer characterized by a high count of diatoms. TC of bacteria was highest in small pack-ice pieces 10—20 kg in being and densely overgrown with diatoms. Bacterial population in pack-ice was dominated by rods (62%), and it contained filamentous bacteria (2.4%) and prosthecate forms (4,8%), rarely present in deep sea. Mean volume of bacterial cell (0,206/μm3) was small, only slightly exceeding that of cells of free-living bacteria in sea water in summer.
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Abstract

Water samples were collected at 12 oceanographic stations from six standard depths ranging from 0 to 100 and 150 m. The number of bacteria and concentration of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under I m2 of sea of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under 1 m2 of sea surface. Total numbers of bacteria (TC) ranged from 0.16 to 7.31 x 107/1 and 1.74 — 5.67 x 10, 2/m2 saprophytic bacteria (CFU) 0.10 — 46.85 x 103/1 and 0.62 — 27.7x 108/m2. contents of particulate organic carbon (РОС) 0.02 — 0.25 mg/1 and 3.5 — 20.0 g/m2 dissolved organic carbon (DOC) 0.07 — 3.02 mg/1 and 53.5 — 207.9 g/m2, dissolved free amino acids (DFAA) 0 — 1.8965 μmol/1 and 2.7 -151.5 mmol/m2, dissolved combined amino acids (DCAA) 0 2.9366 μmо1/1 and 16.5— 163.5 mmol/m2, particulate combined amino acids (PCAA) 0 — 3.0215 μmо1/1 and 3.7 — 249.0 mmol/m2. Total numbers of bacteria and РОС, DOC and DCAA concentrations, widely differentiated in the investigated area, were on the average much lower than the values obtaine in previous years. The saprophytic bacteria content and DFAA and PCAA concentrations were at a similar level to that in the past years. Higher TC and CFU values were observed in the areas with high concentrations of phytoioplankton to the NW of Anvers I. and around Clarence I.
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Abstract

Thermoregulation is fully developed in 5 day old Wilson's storm petrels Oceanites oceanicus (Kuhl). Resting metabolic rate (RMR) and body temperature (Tb) of unattended 1- and 3-day old chicks continuously decrease at ambient temperature (Ta) of 5°C. After being heated the chicks return to normothermia. Ability to survive temporal deep hypothermia seems to be an adaptation to absence of parents and low temperatures in the nest during first days of life. After snow storm, during two days of starvation, chick RMR decreases by 40% at Ta of 0°C, but chick Tb is stable. This suggest decrease of thermal conductance (Ct). Fall of Ct may suggest beginning of hypohermia.
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Abstract

Rocks of the Legoupil Formation in the Cape Legoupil area were folded about a N70E oriented axis. Later these rocks were affected only by brittle deformation which occurred in four stages: (1) jointing — set I, (2) dyking, (3) faulting and, (4) jointing — set II. Both, folding and subsequent brittle deformation, are hardly compatible with the Mesozoic-Cenozoic eastward subduction of the ancient Pacific ocean crust.
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Abstract

Matrix metalloproteinases 2 and 9 (MMP2 and MMP9) are proteolytic enzymes involved with extracellular matrix degradation. They play a role in tumor invasion and metastases. Be- cause of their ability to degrade signaling molecules presented in extracellular matrix, MMPs contribute to tumor proliferation and apoptosis. The aim of this study was to evaluate expression of MMP2 (latent and both active and latent forms) and MMP9 (active, latent, active and latent forms) in different subtypes of canine lymphomas and their relationship with proliferative (mi- totic index and percentage of Ki67-positive cells) and apoptotic (apoptotic index) markers. Ex- pression of MMPs was assessed immunohistochemically using an immunoreactive score system. Expression of both MMPs was found in all 20 examined lymphomas belonging to six subtypes. Most cases showed a moderate level of all analyzed forms of MMP2 and MMP9. High expres- sion of MMPs was found in single cases. Except for a positive correlation between the active form of MMP9 and the mitotic index for all lymphoma cases, no other correlations between any remaining forms of MMPs and neither proliferative nor apoptotic markers were found, irrespec- tive of whether the analysis encompassed all cases or the most numerous lymphoma subtypes i.e. centroblastic and Burkitt-like. Our results were not able to clearly confirm the influence of MMPs on the proliferation and apoptotic activity of canine lymphoma cells. However, further studies examining MMPs activity by zymography, expression of their inhibitors and other factors in- volved in activation of cell proliferation and apoptosis inhibition are needed to clarify the role of MMPs, especially the active form of MMP9, in the behavior of canine lymphoma cells.
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Abstract

Energy delivered to the nests of Wilson's storm petrel, Oceanites oceanicus (Kuhl, 1820), was evaluated by measurement of the oxygen consumption of brooding adult birds and nestlings of different ages. During the brooding period adult birds have to deliver more than 180 kJ per visit to the nest vs. less than 170 kJ during the rest of the nesting period. It seems likely that the parental ability to deliver large quantities of food per visit affects the duration of the brooding period and therefore also affects growth rates of Wilson's storm petrel chicks and the duration of their nesting period.
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Abstract

The paper focuses on investigation of properties of two most widely used self-set sand binder systems APNB and FNB across the Globe, for making molds and cores in foundries to produce castings of different sizes involving wide range of metals and alloys, ferrous and nonferrous. This includes study of compression strength values of samples made out of molding sand at different binder addition level using new, mechanically reclaimed (MR) and thermally reclaimed (TR) sand. Strength values studied include dry strength (at room temperature) at specified intervals simulating different stages of mold handling, namely stripping and pre heating, followed by degraded strength after application of thinner based zircon wash by brush, subsequent lighting of, then checking strength both in warm (degraded strength) & cold (recovered strength) conditions. Throughout the cycle of mold movement from stripping to knock out, strength requirements can be divided into two broad classifications, one from stripping to closing (dry strength) and another from pouring to knock out (hot & retained strength). Although the process for checking of dry strength are well documented, no method using simple equipments for checking hot & retained strength are documented in literature. Attempts have been made in this paper to use some simple methods to standardize process for checking high strength properties using ordinary laboratory equipments. Temperature of 450°C has been chosen by trial & error method to study high temperature properties to get consistent & amplified values. Volume of gases generated for both binders in laboratory at 850°C have also been measured. Nature of gases including harmful BTEX and PAH generated on pyrolysis of FNB and APNB bonded sands are already documented in a publication [1]. This exercise has once again been repeated in same laboratory, AGH University, Poland with latest binder formulations in use in two foundries in India.
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Abstract

The study was conducted on 26 male, 30 days-old goats, separated from their mothers, divided into two equal groups: I - control and II - experimental, consisting of 13 animals each. All animals were fed with milk replacer, experimental group received additionally 50 g/kg body weight, additive of HMB, for 60 days. The following features were analyzed: body weight, daily increases of body weight, as well as hematological and biochemical blood features. Differences in body weight were found, between experimental and control group, after 60 days of experiment 0.57 kg (p≤0.01). The daily weight gain of experimental animals was higher in comparison with control group. Significant differences were also noted in results of hematological and biochemical blood parameters. Experimental animals showed a higher level of red blood cells as well as number of lymphocytes in comparison with the control group, (p≤0.01).Significant changes were also observed in the level of triglycerides, inorganic phosphorus and protein between both groups. The acid-base balance parameters and ionogram, showed a higher pH level (p≤0.05) HCO – act., HCO – std., BE, ctCO , O sat, K+, Cl– (p≤0.01), while the anion gap (AG) and Na+ were significantly lower in control group (p≤0.01).
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Abstract

New coral taxa Tetraporinus siedlecka sp. n. and Roemeripora aspinosa major ssp. n. are erected from the Lower Permian (Sakmarian and Artinskian) Treskelodden Formation of Hornsund area, Spitsbergen and Syringopora sp. similar to S. subreticulata Nowiński, 1991 are described. Studies on stable isotope ratios of carbon and oxygen in the skeletons of tabulate and rugose corals from Hyrnefjellet and Treskelen areas show that these organism did not frac­tion the isotopes to much. The differences in isotope fractionation, both for carbon and oxygen, reached 2 ‰ comparable to the concurring brachiopods, accepted as reference level.
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Keywords parasites

Abstract

What can parasites do? According to Kathleen McAuliffe’s book This is Your Brain on Parasites, they can affect human thinking and behavior, and thus change us into obedient machines.
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Keywords research on food

Abstract

The Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, one of the most robust centers for research on food and its improved quality. This year, the Olsztyn-based Institute celebrates the 30th anniversary of its establishment.
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Abstract

Newcastle disease (ND) is a highly contagious and economically important disease in the poultry industry caused by avian avulavirus-1, historically known as Newcastle disease virus (NDV). Control of ND primarily relies on prophylactic vaccination of flocks, and many vaccines are available on the market, both conventional and more recently introduced new generation recombinant types. To assess the protection level achieved by vaccination ELISA tests are typically used, they also are to track an infection with field strains in non-vaccinated flocks. Special modifications of ELISA can be used as a screening tool to detect infection in flocks vaccinated with new generation vaccines. In this study, we have developed an ELISA test for the detection of antibodies against the nucleoprotein (NP) of NDV and for differentiation of chickens vaccinated with commercial and prototype in-house recombinant vector vaccines from those infected with field NDV strains. The NP gene of LaSota NDV strain expressed in a baculovirus vector was used as a coating antigen in the ELISA. The developed test was optimized, validated and compared to other serological tests. The sensitivity, specificity and accuracy of recombinant NP protein-based ELISA were respectively 96.1%, 96.3%, and 96.2%. Inter-rater (kappa) agreement between the NP-ELISA and the gold standard HI test was calculated to be 0.995. In our comparisons, commercially available ELISA tests revealed different specificities ranging from 95.5–100% and sensitivities at variance, ranging from 90.1 to 99.0%. A high level of maternally derived antibodies was measured in the serum of 1-day-old broilers in the NP-ELISA assay. These antibodies had disappeared and were undetected at 3, 5 and 6 weeks post-vaccination but birds became positive again at 2 weeks after control infection with a velogenic NDV strain. In SPF chickens, antibodies against NP protein were detected only after a challenge. The recombinant NP protein-based ELISA test is sensitive, specific and accurate when compared to the gold standard HI test and commercially available kits. Moreover, the method could be also used for the differentiation between vaccinated and infected birds.
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Abstract

The aim of this study was to determine the effects of factors such as sex, eye-side and diurnal variation on intraocular pressure (IOP) values measured by Tono-Pen Vet® in healthy calves. Twenty four (12 males, 12 females) calves were used in this study. IOP measurements were per- formed in the morning (6:00 a.m.) and at night (8:00 p.m). Average IOP values in all calves were measured as 17.67±2.64 mmHg in the morning and 15.52±2.05 at night and the difference between these two time points was found to be statistically significant (p<0.0001). Average IOP values were measured as 16.04±2.82 mmHg in males and 17.15±2.23 mmHg in females with a statistically significant (p<0.05=0.023) difference between them. Average IOP values were 16.81±2.85 mmHg in right eyes and 16.37±2.23 mmHg in left eyes and the difference between these values were statistically insignificant (p>0.05). At the end of study, overall average IOP in all calves was measured as 16.59±2.59 mmHg. The present data showed a significant difference in terms of sex and diurnal variations and a non-significant difference in eye-side. In addition, this study is the first research article in which the intraocular pressure in calves was measured by Tono-Pen Vet®.
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Abstract

Three tectonic units occur in folded stratified volcanic sequence on Barton Peninsula. Fossil flora (Del Valle et al. 1984) occurs in the basal part of the upper unit which age is not younger than Paleocene. The rocks of the middle and lower units are older, possibly Mesozoie.
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Abstract

Thin coal seams found in the Lions Cove Formation, Polonia Glacier Group (Middle Eocene, upper part) at King George Bay, King George Island (South Shetland Islands, West Antarctica), represent lustrous (vitrine) brown-coal metaphase. The coal from the lower seam represents carbonized wood, probably angiosperm, that from the upper ones originated due to accumulation of branches or larger wood fragments and leaf remains. These coals are slightly older than metaxylite brown coal previously described from Admiralty Bay on King George Island, and dated at Eocene-Oligocene boundary. Both coal occurrences are evidences for a warm climate which prevailed in the Antarctic Peninsula sector during the Arctowski Interglacial (ca 50—32 Ma).
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Abstract

Anthracite coal matter fills irregular voids in dolostones of the Upper Proterozoic Höferpynten Formation in the Hornsund area, south Spitsbergen. The coals are of organic origin, as indicated by a variety of coal-petrographic studies, and by association with algal structures. They probably derived from bitumina accumulated in voids of dolostone at an early diagenelic stage. The degree of coalification (graphitization) is high but diversified, suggesting several coalification stages, probably related t o successive metamorphic events. The oldest changes may correspond to initial stage of t h e greenschist-amphibolite phase of regional metamorphism, with temperatures of over 500°C and pressure of over 20,000 MPa . Multiphase graphite crystallites which occur in t h e coal are mainly fibrous. There are also crystallites which precipitated from gaseous phase, and pyrolitic graphite; they may have originated due to action of mesothermal solutions which had produced ore-bearing veins.
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Abstract

αB-crystallin is a member of a small family of thermal shock proteins that protects cells from stress. Because of lack of its expression in peripheral blood leukocytes, it was proposed as a molecular marker of circulating tumor cells in canine mammary gland tumors. The aim of the present study was to determine if αB-crystallin shows stability of expression, what is the requirement for this type of marker. It was also assessed whether there is co-expression of αB-crystallin with the basal marker, cytokeratin 17. For this purpose, samples of various types of canine mammary gland tumors of epithelial origin, were selected. Using RT-qPCR, we have found αB-crystallin and cytokeratin 17 co-expression in benign and malignant canine mammary gland tumors. It has been demonstrated that the expression of αB-crystallin in tested neoplastic samples is not stable in comparison to the control group. Furthermore αB-crystallin overor down- expression was associated witch the same cytokeratin 17 pattern. αB-crystallin can be a marker of circulating tumor cells in the bloodstream, but for cancers in which basal marker expression occurs and thus not universal for all cancers originating from the mammary gland tissue.
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Abstract

The propagation of EM waves in soil is defined by permittivity and permeability which are in turn affected by the soil parameters such as soil moisture and texture. Therefore, a suitable Dielectric Model like MBSDM is required for the channel characterization of WUSN. Effect of soil parameters and environmental conditions on signal propagation is modelled using Superposition Model. The simulation of these stages is done in MATLAB for UG-UG, UG-AG and AG–UG scenarios. The system is further implemented on the ZYNQ ZC–702 hardware platform.
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Abstract

The results presented in this article are part of the research on fatigue life of various foundry alloys carried out in recent years in the Lukasiewicz Research Network – Institute of Precision Mechanics and AGH University of Science and Technology, Faculty of Foundry Engineering. The article discusses the test results obtained for the EN-GJS-600-3 cast iron in an original modified low-cycle fatigue test (MLCF), which seems to be a beneficial research tool allowing its users to evaluate the mechanical properties of materials with microstructural heterogeneities under both static and dynamic loads. For a comprehensive analysis of the mechanical behaviour with a focus on fatigue life of alloys, an original modified low cycle fatigue method (MLCF) adapted to the actually available test machine was used. The results of metallographic examinations carried out by light microscopy were also presented. From the analysis of the results of the conducted mechanical tests and structural examinations it follows that the MLCF method is fully applicable in a quick and economically justified assessment of the quality of ductile iron after normalizing treatment.
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Abstract

Early castration of male small ruminants is regarded as a risk factor for urolithiasis, although the underlying correlations are still unclear. One possible reason is a deferred development of the penis and the urethra after castration. Therefore, we examined the penis and urethra of castrated and intact lambs by ultrasonography to determine the correlation between urethral area and pe- nile cross-sectional area. Ultrasonography was performed in 6-month-old Lacaune crossbred lambs (early castrated, late castrated, and intact; each group, n = 11). Sectional images at 5 loca- tions (glans penis, penile urethra, distal and proximal sigmoid flexure, and ischial arch) were ob- tained to determine the urethral and penile diameters. Urethral and penile cross-sectional areas were calculated. Grey-scale analysis of ultrasound images was performed to evaluate possible differences in the penile texture between the groups. Correlation analyses between both cross-sectional areas showed a significant general correlation for location 2 in all lambs (R = 0.52; P = 0.003), for location 3 in late-castrated lambs, and for location 5 in early-castrated lambs. Statistically significant correlations between the penile and the urethral area of castrated and intact lambs were not evident. Therefore, measurement of the penile cross-sectional area alone does not allow for accurate estimation of urethral size. Statistically significant differences con- cerning the grey-scale analysis between the groups were also not detectable. Thus, simplification of the formerly presented ultrasonographic examination of the urethra is not recommended. In animals at a risk of obstructive urolithiasis, complete urethral examina- tion is essential.
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Abstract

In our recent study we demonstrated that the holding of fresh semen in fractionated seminal plasma (SP1, >40 kDa; SP2, <40 kDa), obtained by gel filtration chromatography, significantly improved the sperm quality characteristics following cryopreservation (Wasilewska-Sakowska et al. 2019). In this study we investigated the effect of post-thaw (PT) supplementation of fractionated SP (SP1 and SP2) on the survival of spermatozoa from boars with good and poor semen freezability, GSF and PSF, respectively. Two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) analysis showed distinct differences in the protein profiles of SP1 and SP2 from boars with GSF or PSF regarding the number of protein spots. Sperm motility characteristics and the motion patterns, assessed using the computer-assisted sperm analysis (CASA) system, were markedly higher in PT semen supplemented with SP1 and SP2 from boars with GSF. Post-thaw supplementation of either SP1 or SP2 from boars with GSF significantly improved mitochondrial function, plasma membrane and acrosome integrity, and viability during storage. The findings of this study have confirmed that the presence of protective protein components in varying abundance in either fractionated SP from boars with good freezability ejaculates significantly improved the sperm survival following PT storage.
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Abstract

The aim of the study was to assess the physiological stiffness of the normal canine jejunal mucosa based on shear wave elastography. The study was carried out on 60 dogs. In all the animals studied, the abdominal ultrasound was carried out using the SuperSonic Imagine Aixplorer system. The site of the jejunal elastography was determined using standard ultrasonography and all the measurements were carried out thrice. The stiffness of the area examined was determined during each measurement. Mean values were calculated based on the results obtained. The normal stiffness of the jejunal mucosa ranged from 1.305 kPa to 9.319 kPa (mean 5.31 ± 2.04 kPa). Based on our findings, we determined the range of normal values of the jejunal mucosal stiffness in healthy dogs. In addition, shear wave elastography was found to be safe and easy to perform. Moreover, it did not require anaesthesia or patient immobilisation for long periods.
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Abstract

Early recognition of altered lactate levels is considered a useful prognostic indicator in dis- ease detection for both human beings and animals. It is reasonable therefore to hypothesize that a portable, point of care (POC) spectrophotometric device for analysis of lactate levels, may have an application for field veterinarians across a range of conditions and diagnostic procedures. In this study, a total of 72 cattle in the transition period underwent POC spectrophotometric lactate measurement with a portable device (The Vet Photometer) in the field, with a small portion of blood used for comparative ELISA evaluation. Lactate measurements were compared using a of Passing-Bablok regression analysis and Bland-Altman plots. The Vet Photometer lactate mea- surement results were in agreement with those generated by the ELISA method. Values for the agreement were derived, in a 95% CI between -1.3 and 0.99, and a positive correlation (r=0.71) between the two measurements. The equation y= 0.68x + 0.60 was achieved using a Pass- ing-Bablok regression analysis. There were no statistical differences in mean values between the measurement methods. In conclusion, a novel veterinary POC spectrophotometric device “Vet Photometer” is an accurate device for evaluation of lactate levels in healthy transition cows.
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