Evaluation of reticulocyte hemoglobin content (RET‐He) in the diagnosis of iron‐deficient erythropoiesis in dogs

Background

Reticulocyte hemoglobin content provided by the Siemens ADVIA (CHr) is an established marker of iron deficiency. The IDEXX ProCyte Dx hematology analyzer now provides a similar variable, reticulocyte hemoglobin equivalent (RET‐He).

Objectives

The objective was to evaluate RET‐He and its diagnostic utility in dogs, and to calculate a cutoff value for diagnosing iron‐deficient erythropoiesis (IDE). Furthermore, the prevalence of RET‐He values below this cutoff value was established.

Methods

One hundred and seventy‐one CBCs of healthy dogs were used to establish a RI. Stability of RET‐He was evaluated by repeated measurements over 48 hours (n = 10). The 25‐run coefficient of variation (CV) was calculated, and correlation and bias between measurements of RET‐He and CHr were assessed (n = 190). A cutoff value for diagnosing IDE was calculated. The utility of RET‐He in the detection of IDE was evaluated in 123 dogs. The prevalence of low RET‐He values was assessed retrospectively in a multicenter study (2012–2014) under participation of 7 veterinary clinics.

Results

Reticulocyte hemoglobin equivalent with an RI of 22.2 to 28.6 pg was statistically stable over 48 hours (P = .10). The CV was 1.8%. A fair correlation (ρ = 0.74) between RET‐He and CHr with a small bias of ?0.6 pg was found. The cutoff value for diagnosing IDE was 20.9 pg (sensitivity: 85%; specificity: 99%). The prevalence of RET‐He values below 20.9 pg was 10.3% (1084/10,553 dogs).

Conclusions

RET‐He on the ProCyte Dx is a precise screening tool in dogs to detect iron‐deficient erythropoiesis.     

Estimating nocturnal ecosystem respiration from the vertical turbulent flux and change in storage of CO2

Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u_*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u_*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (F_C) and change in storage (F_S) of CO₂ in the few hours after sundown. The sum of F_C and F_S reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration R_Rmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of F_c + F_s extrapolated to zero light, R_LRC, and (3) with a detailed process-based forest ecosystem model, R_cast. At most sites respiration rates estimated using the u_*-filter, R_ust, were smaller than R_Rmax and R_LRC. Agreement of our approach with independent measurements indicates that R_Rmax provides an excellent estimate of nighttime ecosystem respiration.     

Prevalence and risk factors for contamination with Listeria monocytogenes of imported and exported meat and fish products in Switzerland, 1992-2000

A total of 2053 import and 164 export samples from 425 production plants were examined over a 9-year period (1992-2000) for the presence of Listeria monocytogenes (L. monocytogenes) in Switzerland. Overall, 282 samples (12.2%) and 85 plants (20.5%) harbored the pathogen. The highest isolation risk was for marinated fish (38%); the lowest was in cured- and dried-meat products.Unconditional fixed-effect logistic regression was used to identify the main hazards associated with the presence of L. monocytogenes. The plant-level model considered potential risk factors for a positive culture operating at the production-plant level by including a random effect of plant and year.Food category was the only significant factor; sampling site, country of origin and season were not significant. Marinated fish was a strong predictor for positive culture, whereas cooked- and cured-meat products were protective. Plant and year effects were significant. Control measures should be focused on specific food items in each production plant.     

Effect of Season on Travel Patterns and Hoof Growth of Domestic Horses

Four Morgan mares and five Morgan geldings ranging in age from 5- to 12-years-old were fitted with Global Positioning System units to determine if season has an influence on travel pattern. Body and hoof growth measurements were obtained so that the influence of season on body condition and hoof growth could be determined. Waist and heart circumference, cresty neck score, and body condition score were determined in each season. The ambient temperature and precipitation was recorded for each season. Waist circumference was the greatest (P < .05) in the spring and summer and the least in the fall and winter. Hoof growth was the greatest (P < .05) in the fall and the least in the winter. The front and rear hooves grew at similar rates in all horses. Hoof growth in geldings and mares were also similar. The average distances traveled were similar across seasons; however, the horse did numerically travel more in the spring and summer compared with the fall and winter. The range of the travel pattern was influenced by season with the horses traveling significantly less in the winter, although the average travel distances were similar. In conclusion, season in temperate zones will influence body condition, hoof growth, and pattern of travel, but the total distance traveled will be similar. Further research needs to be conducted to determine the influence of season on hoof growth and travel patterns.     

Postanesthetic Pulmonary Edema In an Arab Stallion

A six-year-old arabian stallion was admitted to The Ohio State University Veterinary Hospital for evaluation and repair of a comminuted fracture of the second phalanx. The horse developed impaired arterial oxygenation during surgey and pulmonary edema post-operatively. We postulate that impaired arterial oxygenation resulted from atelectasis of the dependent lung during annesthesia, and the pulmonary edema occurred following re-expansion of the atelectatic of the initiating cause of the edema, removal of excess lung water from the alveoli, and restoration of normal arterial oxygenation. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. This report describes re-expansion pulmonary edema due to reperfusion injury in a horse, treatment of the condition, and a possible explanation of the pathogenesis of this pulmonary pathology.     

Effects of Restored Stream Buffers on Water Quality in Non-tidal Streams in the Choptank River Basin

Restoration of riparian buffers is an important component of nutrient reduction strategies in the Chesapeake Bay watershed. In 1998, Maryland adopted a Conservation Reserve Enhancement Program (CREP), which provides financial incentives to take agricultural land out of production to plant streamside vegetation. Between 1998 and 2005, 1–30% of streamside vegetation (average?=?11%), was restored to forest or managed grass in 15 agriculturally dominated sub-basins in the Choptank River basin, a tributary of Chesapeake Bay. Pre-existing forested buffers represented 10–48% of the streamside (average?=?33%), for a total of 12–61% buffered streamsides (average?=?44%). Using multi-year water quality data collected before and after CREP implementation (1986, 2003–2006), we were unable to detect significant effects of CREP on baseflow nutrient concentrations based on the area of restored buffer, the percentage of restored streamside, or the percentage of total riparian buffer in the sub-basins (p?>?0.05). Although CREP increased the average buffered streamside from 33% in the 1990s to 44% by 2005, N and P concentrations have not changed or have increased in some streams over the last 20 years. Reductions may not have occurred for the following reasons: (1) buffer age, width, and connectivity (gaps) between buffers are also important to nutrient reductions; (2) agricultural nutrient inputs may have increased during this period; and (3) riparian buffer restoration was not extensive enough by 2005 to have measurable affects on the stream water quality in these sub-basins. Significant effects of CREP may yet be resolved as the current CREP buffers mature; however, water quality data through 2006 in the Choptank basin do not yet show any significant effects.     

Glycemic Response to Oat Bran Muffins Treated to Vary Molecular Weight of β‐Glucan

Oat bran muffins, containing 4 or 8 g of β‐glucan per two‐muffin serving, were prepared with or without β‐glucanase treatment to produce a range of β‐glucan molecular weights from 130,000 to just over 2 million. Following an overnight fast, the glycemic responses elicited by the untreated and treated muffins was measured in 10 healthy subjects and compared with a control whole wheat muffin. Taken all together, the 4‐g β‐glucan/serving muffins reduced blood glucose peak rise (PBGR) by 15 ± 6% compared with the control. The 8‐g β‐glucan/serving muffins had a significantly greater effect (44 ± 5% reduction compared with the control, P < 0.05). The efficacy of the muffins decreased as the molecular weight was reduced from a 45 ± 6% reduction in PBGR (P < 0.05) for the untreated muffins (averaged of both serving sizes) to 15 ± 6% (P < 0.05) for muffins with the lowest molecular weight. As the molecular weight was reduced from 2,200,000 to 400,000, the solubility of the β‐glucan increased from a mean of 44 to 57%, but as the molecular weight was further decreased to 120,000, solubility fell to 26%. There was a significant correlation (r² = 0.729, P < 0.001) between the peak blood glucose and the product of the extractable β‐glucan content and the molecular weight of the β‐glucan extracted.     

Antibacterial compounds from marine Vibrionaceae isolated on a global expedition

On a global research expedition, over 500 bacterial strains inhibitory towards pathogenic bacteria were isolated. Three hundred of the antibacterial strains were assigned to the Vibrionaceae family. The purpose of the present study was to investigate the phylogeny and bioactivity of five Vibrionaceae strains with pronounced antibacterial activity. These were identified as Vibrio coralliilyticus (two strains), V. neptunius (two strains), and Photobacterium halotolerans (one strain) on the basis of housekeeping gene sequences. The two related V. coralliilyticus and V. neptunius strains were isolated from distant oceanic regions. Chemotyping by LC-UV/MS underlined genetic relationships by showing highly similar metabolite profiles for each of the two V. coralliilyticus and V. neptunius strains, respectively, but a unique profile for P. halotolerans. Bioassay-guided fractionation identified two known antibiotics as being responsible for the antibacterial activity; andrimid (from V. coralliilyticus) and holomycin (from P. halotolerans). Despite the isolation of already known antibiotics, our findings show that marine Vibrionaceae are a resource of antibacterial compounds and may have potential for future natural product discovery.