Effect of dietary iron content on hematologic and other measures of iron adequacy in dogs

Eighteen 9- to 10-week old Beagles were fed casein-based diets (4,710 kcal of metabolizable energy/kg of body weight) containing either 12, 80, or 160 mg of iron/kg of diet. Growth and feed consumption were monitored throughout the 47-day study. Hematocrit (Hct), hemoglobin (Hb) concentration, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), RBC numbers, erythrocyte protoporphyrin (EP) concentration, serum iron concentration, serum total iron-binding capacity (TIBC), and serum ferritin concentration were determined weekly. Growth rate and feed efficiency were not significantly influenced by dietary iron content. At 14 days, Hb concentration, Hct, MCV, MCH, RBC numbers, and serum iron concentration were significantly (P less than 0.05) lower in dogs fed the 12 mg/kg diet, and remained significantly low for the remainder of the study. Erythrocyte protoporphyrin concentration increased significantly (P less than 0.05) by 14 days in dogs fed the basal diet, and remained significantly high relative to that in dogs of the other dietary groups for the remainder of the study. Serum ferritin concentration decreased in dogs of the group fed the basal diet, with a significant (P less than 0.05) difference beyond day 42. Differences in Hct, MCH, MCV, or hemoglobin, serum iron, serum ferritin, or EP concentration were not found between groups fed 80 and 160 mg of iron/kg of diet. Liver nonheme iron content was significantly (P less than 0.05) affected by dietary iron content.     

Hematologic and biochemical abnormalities indicating iron deficiency are associated with decreased reticulocyte hemoglobin content (CHr) and reticulocyte volume (rMCV) in dogs

BACKGROUND: The ADVIA 120 automated hematology system uses low- and high-angle light scatter to determine individual RBC and reticulocyte volume and hemoglobin (Hgb) concentration. Current hematologic and biochemical markers of iron status in the dog are insensitive, and results may be highly variable, especially in the presence of concurrent disease (ie, inflammation, neoplasia). Reticulocyte Hgb content (CHr) has proven useful in detecting early iron deficiency and iron deficiency masked by concurrent disease in human patients. OBJECTIVES: The purpose of this study was to retrospectively investigate the association of low CHr and reticulocyte MCV (rMCV) with hematologic and biochemical abnormalities indicative of iron deficiency in canine patients. METHODS: Reference intervals for CHr and rMCV were established on a population of 362 hematologically-normal dogs using standard methods. CBC and serum biochemical results from 833 dogs at Colorado State University Veterinary Teaching Hospital were retrospectively evaluated. The prevalence of decreased CHr and rMCV values was determined based on the reference intervals. Hematologic (HCT, MCV) and biochemical (serum Fe concentration, percent saturation of transferrin [% sat]) values were compared among dogs with low CHr (n=58), low rMCV (n=50), and control dogs (cohort groups from the initial population) using a Fisher exact test. RESULTS: Reference intervals were 22.3-27.9 pg for CHr and 77.8-100.2 fL for rMCV. Seven percent (n=58) of dogs in the hospital population had low CHr and 6% (n=50) had low rMCV based on the reference values. Dogs with low CHr had significantly lower HCT, MCV, serum Fe, and % sat values than did control dogs. In addition, dogs with low CHr or low rMCV values had a higher frequency of microcytosis, anemia, low serum Fe concentration, and low % sat than did control dogs. CONCLUSION: Low CHr and low rMCV are associated with hematologic and serum biochemical abnormalities indicative of iron deficiency. CHr and rMCV hold promise as noninvasive, cost-effective measures of iron status in the dog.     

Characterization of Hepatoportal Microvascular Dysplasia in a Kindred of Cairn Terriers

Hepatoportal microvascular dysplasia (MVD), a congenital disorder of the hepatic vasculature, is described in a kindred of Cairn Terrier dogs. Cairn Terrier dogs (n = 165) were evaluated using the serum bile acid test. Affected dogs, identified by abnormal fasting or postprandial serum bile acid concentrations, were divided into 2 groups. Group 1 dogs (n = 147) were used for pedigree analysis. Group 2 dogs (n = 18) were characterized on the basis of history, physical examination, clinicopathologic studies, diagnostic imaging of the liver and portal circulation, and hepatic histopathology. Group 2 contained control dogs (n = 2), dogs with hepatoportal MVD (n = 11), and dogs with macroscopic portosystemic vascular anomalies (PVSA) (n = 5). With the exception of high serum bile acid concentrations, dogs with hepatoportal MVD were indistinguishable from control dogs on the basis of history, physical examination, clinicopathologic findings, survey abdominal radiography, abdominal ultrasound, or transcolonic scintigraphy. Contrast portography in dogs with MVD revealed abnormalities of terminal twigs of the portal vasculature with out large intrahepatic or extrahepatic shunting vessels. Histopathologic abnormalities in dogs with hepatoportal MVD were similar to those reported for dogs with PSVA. Pedigree analysis suggested an autosomal inheritance for MVD. Dogs with MVD had high serum bile acid concentrations, abnormal indocyanine green clearance, and hepatic pathology suggestive of PSVA, but they lacked characteristic clinical findings of PSVA. The clinical significance of MVD is unclear. Dogs with MVD were clinically normal when evaluated but long-term follow-up is not yet available. Dogs with hepatoportal MVD should be identified at an early age to avoid confusion in future diagnostic evaluations. J Vet Intern Med 1996:10:219–230. Copyright © 1996 by the American College of Veterinary Internal Medicine .     

Effect of storage on microcytosis observed in dogs with portosystemic vascular anomalies

Microcytosis is a common laboratory finding in dogs with iron deficiency and congenital portosystemic vascular anomalies (PSVA), however artefactual changes due to blood storage may occur which could mask this feature. This study evaluated the effects of storage on microcytosis in dogs with congenital PSVA. Full haematological parameters were measured on the day of sampling and following 24h storage at room temperature, in unaffected dogs (n=13) and in dogs affected with PSVA (n=24). Storage for 24h resulted in significantly higher MCV values in both groups of dogs (P<0.01). The percentage increase in MCV was greater in the control dogs (median 8.07%, range 5.64-9.31%) compared to affected dogs (median 6.05%, range 3.12-15.21%) (P<0.02). Storage of 1ml EDTA blood samples at ambient temperature for 24h prior to analysis, as occurs when samples are posted to external laboratories, will have significant effects on MCV and may mask microcytosis in dogs with PSVA.     

Hematological changes during the course of canine babesiosis caused by large Babesia in domestic dogs in Warsaw (Poland)

In the presented study we evaluated the hematological changes in samples of blood obtained from 248 dogs naturally infected with large Babesia. The evaluation included red blood cell count, hemoglobin concentration, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), leucocyte counts, thrombocyte counts, mean platelet volume (MPV), morphology of erythrocytes and leucogram. The most common disorders in affected dogs were thrombocytopenia and anisocytosis. The count of erythrocytes below reference values was detected in 26.2% of dogs and 31.4% of affected animals presented hematocrit below the reference values. Hemoglobin concentration below the reference values was noted in 29% of dogs, an increase of MCHC above normal values was detected in 21% of examinated dogs and MCV below normal values was recognized in 2% of dogs. 60.5% of dogs presented anisocytosis, 25% poikilocytosis, 23.8% polychromasia, 19.7% hypochromia and 4.4% erythroblastosis. Thrombocytopenia was detected in 99.5% of dogs, but only 15.3% of examined animals showed increase of MPV, which suggests a response of the bone marrow. 36.3% of dogs had neutropenia, and 21.8% presented a left shift, 14.9% had the lymphocytosis and 7.2% lymphopenia.     

Association of maximum voluntary dietary intake of freeze-dried garlic with Heinz body anemia in horses

OBJECTIVE: To characterize hematologic and clinical consequences of chronic dietary consumption of freeze-dried garlic at maximum voluntary intake in horses. ANIMALS: 4 healthy sex- and age-matched horses. PROCEDURE: An initial garlic dose (0.05 g/kg, twice daily) was fed to 2 horses in a molasses carrier as part of their normal ration and was gradually increased to maximum voluntary intake (0.25 g/kg, twice daily) over 41 days. Dietary supplementation then continued for a total of 71 days. Two control horses were fed molasses with no garlic with their ration. Blood samples were collected weekly and analyzed for hematologic and biochemical changes, including the presence of Heinz bodies. Recovery of affected blood values was followed for 5 weeks after termination of dietary supplementation with garlic. RESULTS: At a daily dose of > 0.2 g/kg, horses fed garlic developed hematologic and biochemical indications of Heinz body anemia, as characterized by increases in Heinz body score (HBS), mean corpuscular volume (MCV), mean corpuscular hemoglobin, platelet count, and serum unconjugated and total bilirubin concentrations and decreases in RBC count, blood hemoglobin concentration, mean corpuscular hemoglobin concentration, and serum haptoglobin concentration. Recovery from anemia was largely complete within 5 weeks after termination of dietary supplementation with garlic. Heinz body score and MCV remained high at the end of the 5-week recovery period. CONCLUSIONS AND CLINICAL RELEVANCE: Horses will voluntarily consume sufficient quantities of garlic to cause Heinz body anemia. The potential for garlic toxicosis exists when horses are chronically fed garlic. Further study is required to determine the safe dietary dose of garlic in horses.     

Evaluation of serum bile acid concentrations for the diagnosis of portosystemic venous anomalies in the dog and cat

The serum concentration of bile acids was measured in dogs and cats with portosystemic venous anomalies (PSVA). In 14 dogs, the mean serum bile acid concentration after 12 hours of fasting was 61.7 +/- 68.7 mumol/L (normal, 2.3 +/- 0.4 mumol/L (SEM) and when measured 2 hours after a meal in 15 dogs was 229.9 +/- 87.7 mumol/L (normal, 8.3 +/- 2.2 mumol/L). The fasting serum bile acid concentration was within the normal range in 5 of 14 dogs. The postprandial concentration was determined in 3 of the 5 and in each case increased more than tenfold above the fasting value. The mean fasting serum bile acid concentration in 4 cats was 24.4 +/- 10.1 mumol/L (normal, 1.7 +/- 0.3 mumol/L) and in 2 of the cats increased to a mean of 120.6 mumol/L (normal, 8.3 +/- 0.8 mumol/L) 2 hours after feeding. The bile acid values in patients with PSVA were correlated with values for blood ammonia content, sulfobromophthalein (BSP) retention, and results of conventional tests of hepatic function. Bile acid concentrations were more sensitive than abnormalities in serum enzyme activities or BSP retention and equal in sensitivity to the ammonia tolerance test in detecting hepatobiliary insufficiency. Bile acid measurements were accomplished with less inconvenience to the patient and clinician, than tests of BSP excretion or ammonia tolerance. Used in combination with conventional laboratory tests for hepatic disease, pre- and postprandial serum bile acid concentrations appear to be a sensitive and specific indicator of hepatobiliary dysfunction of value in the diagnosis of PSVA in the dog and cat.     

Erythrocyte changes, serum iron concentration and performance following iron injection in neonatal beef calves

The injection of iron-dextran into beef calves at an early age immediately increased values for erythrocyte (RBC) numbers, hemoglobin (Hb) concentration, packed cell volume (PCV), mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV), even though the calves were not anemic. There were no significant differences in average daily gain (ADG) from birth through 15 wk between those that were injected and those that were not injected. Hereford calves had lower values for PCV, Hb, MCH and MCV than Angus and crossbred calves, and both Hereford and Angus calves had lesser body weight and slower ADG than crossbred calves. Serum iron (Fe) concentrations were higher in calves born in the spring and pastured in the summer than in calves born in late summer and fall and pastured in the fall. The serum Fe concentration of calves at first sampling (during first week of life) was positively correlated with their weight at that and subsequent times to 15 wk. Mean corpuscular volume and MCH in cows before calving were positively correlated with the MCV and MCH in their calves at first sampling. Serum Fe concentration in cows before calving was negatively correlated with the ADG of their calves through 15 wk.     

Evaluation of plasma protein C activity for detection of hepatobiliary disease and portosystemic shunting in dogs

OBJECTIVE: To determine the diagnostic value of protein C (PC) for detecting hepatobiliary disease and portosystemic shunting (PSS) in dogs. DESIGN: Prospective study. ANIMALS: 238 clinically ill dogs with (n = 207) and without (31) hepatobiliary disease, including 105 with and 102 without PSS. PROCEDURES: Enrollment required routine hematologic, serum biochemical, and urine tests; measurement of PC activity; and a definitive diagnosis. Total serum bile acids (TSBA) concentration and coagulation status, including antithrombin activity, were determined in most dogs. Dogs were grouped into hepatobiliary and PSS categories. Specificity and sensitivity were calculated by use of a PC cutoff value of 70% activity. RESULTS: Specificity for PC activity and TSBA concentrations was similar (76% and 78%, respectively). Best overall sensitivity was detected with TSBA, but PC activity had high sensitivity for detecting PSS and hepatic failure. Protein C activity in microvascular dysplasia (MVD; PC > or = 70% in 95% of dogs) helped differentiate MVD from portosystemic vascular anomalies (PSVA; PC < 70% in 88% of dogs). A receiver operating characteristic curve (PSVA vs MVD) validated a useful cutoff value of < 70% activity for PC. CONCLUSIONS AND CLINICAL RELEVANCE: Combining PC with routine tests improved recognition of PSS, hepatic failure, and severe hepatobiliary disease and signified a grave prognosis when coupled with hyperbilirubinemia and low antithrombin activity in hepatic failure. Protein C activity can help prioritize tests used to distinguish PSVA from MVD and sensitively reflects improved hepatic-portal perfusion after PSVA ligation.     

Reticulocyte indices in a canine model of nutritional iron deficiency

BACKGROUND: Reticulocyte indices, especially reticulocyte hemoglobin content (CH retic), have shown promise as markers of iron deficiency (ID), but there have been no prospective investigations of reticulocyte indices in experimental models of ID. OBJECTIVES: The objective of this study was to compare reticulocyte indices with conventional hematologic and biochemical indices as markers of ID in dogs. METHODS: Iron deficiency was induced in 7 dogs by feeding an iron-deficient diet, and corrected by restoring dietary iron and by giving iron parenterally. Blood samples were collected at weekly intervals. Results of hematologic and biochemical tests were compared using t-tests and receiver operator characteristic (ROC) curve analysis. RESULTS: Comparing mean values on days 0 and 35, by which time hemoglobin concentration decreased to 90% of baseline in all dogs, % Macro retic, % Hypo retic, % Low CH retic, and % High CH retic differed by greater than 3-fold, whereas no conventional hematologic or biochemical indices differed by as much as 2-fold. Comparing conventional hematologic and reticulocyte indices by ROC curve analysis using 4 different biochemical diagnostic criteria of ID, CH retic, % Hypo retic, % Low CH retic, and % High CH retic had higher areas under the curve (AUC) than either MCV conv or MCHC conv according to all 4 criteria, and % Macro retic and MCV retic had higher AUC values according to 3 of 4 criteria (differences were not always statistically significant). CONCLUSIONS: Results of this study support the value of reticulocyte indices in the diagnosis and monitoring of ID in dogs. Species similarities in the pathophysiology and hematologic manifestations of ID suggest these findings also may be relevant to ID in people.     

Microcytosis and Iron Status in Dogs With Surgically Induced Portosystemic Shunts

Microcytosis is common in dogs with congenital portosystemic shunts (PSS) and acquired liver disease. The objective of this study was to determine if microcytosis could be induced in normal dogs by surgical creation of PSS, and to characterize the changes in hematology and iron status. Hematocrit, mean cell volume, mean cell hemoglobin, and mean cell hemoglobin concentration decreased linearly from 45.5%. 69.1 fL, 22.8 g/dL and 33.1% to 39.5%. 55.9 fL, 17.8 g/dL and 31.9%. respectively, 18 weeks after creation of PSS. The erythrocyte count did not change, but red cell distribution widths indicated a shift to a heterogenous population with decreased volume. Mean cell volume and mean cell hemoglobin decreased rapidly after induction of PSS and were significantly ( P < .05) different from presurgery values within 2 weeks. Serum iron and copper concentrations and total iron binding capacity were decreased in dogs with PSS. Liver iron concentration doubled after creation of PSS, with the majority of stainable iron located in Kupffer cells. The changes in erythrocyte indices and measures of iron status in dogs with surgically induced PSS were similar to those in dogs with congenital PSS. Microcytosis developed rapidly in dogs after induction of PSS. These results indicate that iron deficiency was not the cause of microcytosis in these dogs.     

Relationship of serum ferritin and iron concentrations and serum total iron-binding capacity to nonheme iron stores in dogs

The relationships of various iron-related analytes were evaluated in 95 dogs. Liver and spleen nonheme iron content was determined coulometrically on acid-digested tissue specimens. Serum iron concentration and total iron-binding capacity also were measured coulometrically, whereas serum ferritin concentration was measured by ELISA. Significant (P less than 0.0002) correlation was found between serum ferritin concentration and nonheme iron stores. Significant correlation was not found between nonheme iron stores and serum iron concentration or total iron-binding capacity. Serum ferritin concentration should provide a convenient and relatively noninvasive means of estimating iron stores in dogs.     

Predicted mean corpuscular volume as an indicator of bone marrow iron in anemic dogs

A predicted mean corpuscular volume (PMCV) was calculated from the reticulocyte percentage and compared to the actual mean corpuscular volume for the purpose of determining bone marrow iron depletion in the dog. A difference of greater than 10 fl between the pMCV and the actual measured MCV accurately predicted the absence of stainable iron in bone marrow aspirates (sensitivity 86%, specificity 93%). The difference (Diff) between the predicted and actual measured MCV may also be a valuable method for following response to iron therapy in dogs with iron deficiency anemia without the necessity for repeated bone marrow examination. The predicted MCV may be useful in determining which patients are not at risk for canine iron deficiency.     

Bile acid concentrations in the diagnosis of hepatobiliary disease in the dog

The clinical usefulness of measuring serum bile acid concentrations as a diagnostic test for hepatobiliary disease, was examined in 150 dogs that were suspected of having hepatic disease. Serum values of total bilirubin (TB), alkaline phosphatase (ALP), alanine transaminase (ALT), and albumin were also measured. Fasting serum bile acid (FSBA) values were determined, using a solid-phase radioimmunoassay for total conjugated bile acids or a direct enzymatic spectrophotometric method. A definitive diagnosis was established by histologic examination of the liver. On the basis of histologic findings, dogs were assigned to groups (1 to 8, respectively) including: extrahepatic bile duct obstruction, cirrhosis, portal systemic vascular anastomosis (PSVA), hepatic necrosis, intrahepatic cholestasis, steroid hepatopathy, neoplasia, and secondary disease. Dogs in group 8 had no morphologic evidence of hepatobiliary disease or had mild hepatic lesions. Test efficacies of FSBA, TB, ALP, ALT, and albumin were expressed using 4 indices: sensitivity, specificity, and positive-predictive and negative-predictive values. The diagnostic efficacy of FSBA was examined alone and in combinations with the other tests. There was wide overlapping of FSBA values among dogs in groups 1 to 7, and there was wide overlapping of ALT and ALP values among dogs in all groups. The specificity of FSBA for the diagnosis of liver disease exceeded 90% at values greater than or equal to 30 mumol/L and reached 100% at greater than or equal to 50 mumol/L. Individual liver tests with the best sensitivity for each group were:FSBA and ALP for extrahepatic bile duct obstruction; FSBA for cirrhosis and PSVA; ALT for hepatic necrosis; and ALP for intrahepatic cholestasis, steroid hepatopathy, and neoplasia. Combinations of tests with the best sensitivity for each group were: FSBA + ALP for extrahepatic bile duct obstruction; FSBA + ALT for cirrhosis and PSVA; FSBA + ALT and TB + ALT for hepatic necrosis; and FSBA + ALP for intrahepatic cholestasis, steroid hepatopathy, and neoplasia. Individual tests had the best sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of clinical status, renal function, and hematopoietic variables after unilateral nephrectomy in canine kidney donors

OBJECTIVE: To determine clinical status and renal and hematopoietic function after kidney donation and identify risks associated with kidney donation in dogs. DESIGN: Prospective study. ANIMALS: 14 dogs that underwent unilateral nephrectomy for kidney donation. PROCEDURES: Records were reviewed retrospectively to collect data regarding prenephrectomy clinicopathologic variables. Dogs were reexamined prospectively at various times after nephrectomy, and pre- and postnephrectomy CBC, serum biochemical analyses, urinalysis, and urine protein-to-urine creatinine ratio were compared. Six dogs had postnephrectomy renal volume determined ultrasonographically, and 4 of those dogs also underwent scintigraphic determination of glomerular filtration rate and renal biopsy. RESULTS: All dogs were clinically normal at the time of reevaluation. There were no significant differences between prenephrectomy and postnephrectomy values for BUN concentration or urine specific gravity. Mean postnephrectomy serum creatinine concentration was significantly greater than prenephrectomy concentration. Mean serum phosphorus concentration was significantly decreased after nephrectomy, and mean Hct, corpuscular volume, and corpuscular hemoglobin concentration were significantly increased after nephrectomy. Postnephrectomy renal volume was greatest in dogs < 12 months old at the time of surgery. Mean postnephrectomy glomerular filtration rate was 2.82 +/- 1.12 mL/kg/ min (1.28 +/- 0.51 mL/lb/min). Renal biopsy specimens obtained during and after nephrectomy were histologically normal. CONCLUSIONS AND CLINICAL RELEVANCE: Renal and hematopoietic variables were within reference ranges in dogs examined up to 2.5 years after unilateral nephrectomy. Compensatory renal hypertrophy was greatest in dogs < 1 year of age at donation. Donor age, along with histocompatability, may be an important factor in selecting dogs for kidney donation.     

Desferoxamine and iron dextran in acute Salmonella cholerae-suis infection in pigs

Serum iron (SI)-related and hematologic changes were evaluated in a herd of weaned pigs inoculated with a strain of Salmonella cholerae-suis, causing 83% mortality within 22 days after inoculation was done. Serum iron concentrations decreased to 35% of base-line values 2 days after inoculation was done, but recovered to near base line subsequently. Total SI-binding capacity (TIBC) decreased gradually for 14 days after inoculation was done. Transferrin (TF) concentrations decreased to near half the base line throughout the postinoculation observation period. The calculated SI saturation coefficient decreased to half the base line, but recovered to or above the base-line value subsequently. Combined observations of SI, TIBC, TF, and SI saturation coefficient concentrations indicated that there was higher saturation of host iron-binding proteins and recruitment of additional iron-binding systems subsequent to 2 days after inoculation was done. Day 2 after inoculation seemed to be a critical period for host iron metabolism. Injection of supplemental iron dextran simultaneously with Salmonella infection resulted in lower mortality of iron-injected pigs (P less than 0.005). A highly significant negative correlation was observed between SI concentration and rectal temperatures after pigs were inoculated with Salmonella (r = -0.54; P less than 0.0001). Hemoglobin concentrations, mean corpuscular volume, and mean corpuscular hemoglobin were not significantly affected by Salmonella infection or iron injection concurrent with Salmonella infection.(ABSTRACT TRUNCATED AT 250 WORDS)     

Enzyme-linked immunosorbent assay to quantitate serum ferritin in black and white ruffed lemurs (Varecia variegata variegata).

Lemurs in captivity progressively accumulate iron deposits in a variety of organs (hemosiderosis) including duodenum, liver, and spleen throughout their lives. When excessive, the toxic effects of intracellular iron on parenchymal cells, particularly the liver, can result in clinical disease and death. The pathogenesis of excessive iron storage in these species has been attributed to dietary factors related to diets commonly fed in captivity. Tissue iron stores can be directly estimated by tissue biopsy and histologic examination, or quantitated by chemical analysis of biopsy tissue, However, expense and risk associated with anesthesia and surgery prevent routine use of tissue biopsy to assess iron status. A noninvasive means of assessing total body iron stores is needed to monitor iron stores in lemurs to determine whether dietary modification is preventing excessive iron deposition, and to monitor potential therapies such as phlebotomy or chelation. Serum ferritin concentration correlates with tissue iron stores in humans, horses, calves, dogs, cats, and pigs. Serum ferritin is considered the best serum analyte to predict total body iron stores in these species and is more reliable than serum iron or total iron binding capacity, both of which may be affected by disorders unrelated to iron adequacy or excess including hypoproteinemia, chronic infection, hemolytic anemia, hypothyroidism, renal disease, and drug administration. We have developed an enzyme-linked immunosorbent assay to measure serum ferritin in lemurs. The assay uses polyclonal rabbit anti-human ferritin antibodies in a sandwich arrangement. Ferritin isolated from liver and spleen of a black and white ruffed lemur (Varecia variegata variegata) was used as a standard. Ferritin standards were linear from 0 to 50 microg/L. Recovery of purified ferritin from lemur serum varied from 95% to 110%. The within-assay variability was 4.5%, and the assay-to-assay variability for three different samples ranged from 10% to 17%. The assay also measures serum ferritin in several other lemur species.     

Diagnostic value of reticulocyte indices for the assessment of the iron status of cats with chronic kidney disease

BackgroundReticulocyte indices have been suggested as alternatives to transferrin saturation (TSAT) for iron status assessment in humans and dogs but they have not been evaluated thoroughly in cats.ObjectivesTo assess the value of the reticulocyte indices for the diagnosis of iron deficiency in cats with chronic kidney disease (CKD) and chronic hematuria associated with subcutaneous ureteral bypasses (SUBs).AnimalsSixty‐four cats: 16 healthy, 14 CKD without SUB, and 34 CKD with SUB.MethodsProspective observational cross‐sectional study of cats presented for routine nephrology visits. Primary outcomes included assessment of the diagnostic values of erythrocyte indices (mean corpuscular volume, hemoglobin, and hemoglobin concentration: MCV, MCH, and MCHC) and reticulocyte indices (mean corpuscular volume, MCVr; corpuscular hemoglobin, CHr), using TSAT as reference.ResultsIron deficiency was diagnosed in 9/64 cats (14%). A receiver‐operating characteristic curve analysis yielded a moderate discriminatory value for CHr in this diagnosis: area under the curve [AUC] = .75 (95% confidence interval, 0.48‐0.89); P = .006; sensitivity 67%, specificity 82% for a cutoff of 15.9 pg. This compared favorably to MCVr (AUC = .63; P = .29), MCV (AUC = .58; P = .45), MCH (AUC = .64; P = .19), and MCHC (AUC = .7; P = .03).Conclusion and Clinical ImportanceCHr added moderate value to the diagnosis of iron deficiency in cats with CKD.     

不同海拔高度西藏高原牦牛若干血液生理常值的比较

本试验对西藏藏北高原那曲(海拔4500米)牦牛,藏南河谷林芝(海拔3000米)牦牛进行了某些高原生理特性对比研究。测定了红细胞总数、红细胞压积、血液总量、血红蛋白含量及其电泳分析、血清蛋白含量及其电泳分析等。测定结果表明,生活在高海拔的藏北那曲牦牛,其红细胞总数、红细胞压积、血液总量、血红蛋白均极明显地高于较低海拔的藏南河谷牦牛,而其红细胞容积的立方微米数值较小,红细胞内血红蛋白的平均重量较轻,并发现变异血红蛋白(A_3)。根据本文分析,其主要归因于高海拔、低氧压。雄性牦牛的变异血红蛋白数量高于雄牦牛,差异极显著(P相似文献   

Serum zinc, chromium, and iron concentrations in dogs with lymphoma and osteosarcoma

We compared serum concentrations of zinc, chromium, and iron in dogs with cancer to those of normal dogs. Dogs with lymphoma (n = 50) and osteosarcoma (n = 52) were evaluated. Dogs with lymphoma had significantly lower (P = .0028) mean serum zinc concentrations (mean +/- SD; 1.0 +/- 0.3 mg/L) when compared to normal dogs (1.2 +/- 0.4 mg/L). Dogs with osteosarcoma also had lower mean serum zinc concentrations (1.1 +/- 0.4 mg/L), but this difference was not significant (P = .075). Serum chromium concentrations were significantly lower in dogs with lymphoma (2.6 +/- 2.6 microg/L, P = .0007) and osteosarcoma (2.4 +/- 3.1 microg/L, P = .0001) compared to normal dogs (4.7 +/- 2.8 microg/L). Serum iron concentrations and total iron-binding capacity were significantly lower in dogs with lymphoma (110.8 +/- 56.7 microg/dL, P < .0001, and 236.6 +/- 45.6 microg/dL, P < .0001, respectively) and osteosarcoma (99.6 +/- 49.3 microg/dL, P < .0001, and 245.0 +/- 43.8 microg/dL, P = .0011, respectively) when compared to normal dogs (175.1 +/- 56.7 microg/dL and 277.1 +/- 47.4 microg/dL). Mean ferritin concentration was significantly higher in dogs with lymphoma (1291.7 +/- 63.0 microg/L) than in normal dogs (805.8 +/- 291.1 microg/L, P < .0001) and dogs with osteosarcoma (826.5 +/- 309.2 microg/L, P < .0001). Further investigation is needed to explore the clinical significance of these mineral abnormalities in dogs with cancer.