Effect of immune-mediated erythrocyte agglutination on analysis of canine blood using a multichannel blood cell counting system

Blood from six dogs with in vitro immune-mediated erythrocyte agglutination resulted in analytical errors in directly measured counting and sizing functions on a multichannel blood analysis system with histogram capability. Errors in the directly measured values, mean cell volume (MCV), and erythrocyte count were attributed to agglutinated erythrocyte particles that persisted during the relatively short reagent contact time of the analysis. Agglutinated particles less than 240 fl were visible on erythrocyte histograms and resulted in a false low erythrocyte count and false high MCV. Agglutinated cell particles greater than 240 fl were not present on the histogram scale. Because these latter particles exceeded the upper threshold, they did not influence determination of MCV, but resulted in a further decrease in the erythrocyte count. As a result, the other dependent erythrocyte indices were in error. These included false low hematocrit and false high mean corpuscular hemoglobin concentration (MCHC), when compared to corrected reference blood values. Similar errors occurred when analyzing blood samples that were agglutinated in vitro by incubating erythrocytes with incompatible plasma. The counting and sizing errors observed with electronic counting techniques were eliminated or greatly reduced by incubating blood in cell counting diluent for 10 minutes followed by analysis on a single channel counter with attached particle size analyzer. Error in erythrocyte measurement on a multichannel system may be anticipated if there is overt erythrocyte agglutination in a blood sample, an abnormally high MCHC is reported by the system, or subpopulations of large volume (agglutinated cells) are observed on a volume distribution histogram.     

Comparison of two automated multi-channel blood cell counting systems for analysis of blood of common domestic animals

An automated, multi-channel blood cell counting system (S-Plus) was compared to a reference counting system using blood samples from 187 animals of four species. The standard red cell bath aperture current of 150 volts (V) was used during analysis of 75% of the samples. At this setting, all samples with a Mean Corpuscular Volume (MCV) greater than 50 fl had accurate erythrocyte counts. As the MCV decreased below 50 fl, the severity of false low erythrocyte counts and false high MCV values increased. The remaining 25% of samples were analyzed with the red cell bath aperture current increased to 200 V. At this setting, only 5% or less of erythrocytes from animals with normal MCV values(>36 fl)were below the erythrocyte threshold. The red cell distribution width values provided by the S-Plus indicated that equine and bovine erythrocytes have greater anisocytosis than canine and feline erythrocytes. Leukocyte counts were significantly lower on the S-Plus (p<0.01). Canine and equine samples most frequently had platelet size distribution within the S-Plus platelet counting threshold window. Electronic whole blood platelet counting appeared unsatisfactory in cats due to large platelet size and erythrocyte-platelet size overlap. Small platelet size in cattle indicated that further modifications of the red cell bath aperture current would be required to count and size platelets in this species. Following electronic modifications, this state-of-the-art system appears adaptable to hematologic profiling in most species.     

Analysis of feline,canine and equine hemograms using the QBC VetAutoread

Blood samples form 120 consecutive clinical cases (40 cats, 40 dogs and 40 horses) were analyzed on the QBC VetAutoread analyzer and the results compared with those obtained by a Baker 9000 electronic resistance cell counter and a 100-cell manual differential leukocyte (WBC) count. Packed cell volume (PCV), hemoglobin (Hb) concentration, mean cell hemoglobin concentration (MCHC), and platelet, total WBC, granulocytes, and lymphocyte plus monocyte (L+M) counts were determined. Indistinct separation of red blood cell and granulocytes layers on the QBC VetAutoread was observed in samples from five cats (12.5%), two dogs (5%), and one horse. Significantly different (P=0.002) median values for the two methods were obtained for PCV, Hb concentration, MCHC and platelet count in cats; PCV, MCHC, WBC, count and granulocytes count in dogs; and PCV, Hb concentration, MCHC and WBC, granulocytes and platelet counts in horses. Results from the QBC VetAutoread should not be interpreted using reference ranges established using other equipment. Results were abnormal on a limited number of samples; however, when correlation coefficients were low, marked discrepancy existed between values within as well as outside of reference ranges. Spearman rank correlation coefficients were excellent (r=0.93) for PCV and Hb concentration in dogs, and Hb concentration and WBC count in horses. Correlation was good (r=0.80-0.92) for PCV and Hb concentration in cats, WBC count in dogs, and PCV, granulocytes count and platelet count in horses. For remaining parameters, correlation was fair to poor (r=0.79). Acceptable correlations (r>0.80) were achieved between the two test systems for all equine values except MCHC and L+M count, but only for PCV and HB concentration in feline and canine blood samples.     

Haematological profile of crossbred dairy cattle to monitor herd health status at medium elevation in Central Himalayas

Haematological profile-haemoglobin concentration (Hb), total erythrocytes count (TEC), packed cell volume (PCV), erythrocyte indices-mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were studied in crossbred dairy cattle (Holstein Friesian x Sahiwal) under various physiological states: non-pregnant heifers (NPH), pregnant heifers (PH), empty dry cows (EDC), pregnant lactating cows (PLC), medium yield early lactating cows (MYELC) and high yield early lactating cows (HYELC) during summer and winter seasons at 1700 metres altitude from mean sea level in the Central Himalayas. On comparison of annual means, the highest values of Hb and PCV were recorded in PH and of TEC in NPH, whereas the lowest values of these parameters were found in EDC. The Hb and TEC tended to decrease with increasing milk yield. Comparison of annual means of erythrocyte indices revealed the highest MCV and MCH in EDC, which simultaneously showed the lowest MCHC. Significant seasonal variations in haematological profile were recorded. The overall group mean (OGM) of Hb, MCV, MCH and MCHC was found to be significantly higher (P < 0.01) during summer whereas the TEC and PCV showed higher OGM (P < 0.01) during the winter season.     

Reference values of the red blood profile in beagle, German shepherd and golden retriever puppies

In the present study, blood samples were taken from clinically healthy puppies of the breeds Beagle, German Shepherd, and Golden Retriever between days 1 and 3 (n = 146), 8 and 10 (n = 137), 28 and 33 (n = 151), and 50 and 58 (n = 129) post natum. Measurements for red blood cell count, haemoglobin concentration, haematocrit, mean erythrocyte volume (MCV), mean corpuscular haemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC) were performed by a semi-automatic blood cell counter; the normoblast number was counted visually. Between the 1st and 3rd day of life, the erythrocyte number of the puppies was 4.57 +/- 0.68 10(6)/microliter and, as such, was clearly below the reference range for adult animals. It further decreased by the 2nd measurement (8th to 10th day of life) to 3.59 +/- 0.41 10(6)/microliter, and then increased again to 4.75 +/- 0.68 10(6)/microliter (reference range: 3.73-6.25 10(6)/microliter, 2.5% to 97.5% percentile) by the final measurement (50th to 58th day of life). The measurement values of the haemoglobin concentration (13.5 +/- 2.0 g/dl) and haematocrit (41.0 +/- 6.5%) after birth were only insignificantly below or around the lower limit of the reference range for adult animals. Both parameters decreased to a more pronounced extent than did the erythrocyte count. They reached a minimum of 8.4 +/- 1.0 g/dl and 26.8 +/- 3.2%, respectively, between the 28th and 33rd day of life. Even at the end of the examination period (50th to 58th day of life), the values of these parameters (10.1 +/- 1.1 g/dl, reference range: 7.5-11.8 g/dl; 32.1 +/- 4.2%, reference range: 24.8 to 40.8%) were remarkably lower than the minimum of reference range for adult dogs. At the 1st sampling (between 1st and 3rd day of life), MCV (89.8 +/- 6.7 fl) and MCH (29.6 +/- 1.9 pg) were distinctly higher than the reference values for adult dogs. Both parameters decreased with increasing age. Thus, from the 50th-58th day of life, the results were comparable to those of adults. No considerable age dependence was found for MCHC. During the first days of life a relatively high number of normoblasts (8 +/- 7/100 Leukozyten) was found; it decreased rapidly. The study revealed significant differences between the breeds, e.g. German Shepherd dogs had lower initial values of erythrocyte count, haemoglobin concentration, and haematocrit when compared to the other breeds. Puppies of this breed also had higher normoblast numbers than the Beagle and Golden Retriever puppies at the 2nd and 3rd samplings. No clear sex differences in the studied parameters were observed. The results of this study reflect the replacement of fetal erythrocytes by postnatal erythrocytes. Moreover, they illustrate the need to use age as well as breed-specific reference ranges.     

Performance,endoparasitary control and blood values of ewes locally adapted in semiarid region

This study evaluated the variation in the prevalence of endoparasitoses and their impact on body condition and blood values of sheep of the Morada Nova breed. A total of 138 ewes were examined for their morphology (body weight, BW; body condition score, BCS), parasitology (faecal egg count, FEC; Famacha© score; coproculture), hematology (red blood cell count,RBC); hemoglobin concentration, HE; packet cell volume, PCV; mean corpuscular volume, MCV,; mean corpuscular hemoglobin, MCH; mean corpuscular hemoglobin concentration, MCHC; leukocytes, WBC) and serum biochemistry (glucose, cholesterol, triglycerides, urea, creatinine, total protein, albumin, globulin, AST and ALT). Overall the animals presented higher BW and BCS in the months of September and December, however, with high FEC, in addition to a large number of animals with Famacha score 4 and 5. The results showed that the main hematophagous worm affecting the sheep, the genus Haemonchus ssp, appeared in a greater proportion (30–71.66%) than the other worms in all months of the study, except in March. About 30% of the hematological values found in the study are outside the reference ranges for suable sheep e 45.50% for serum biochemistry. These findings demonstrate the most healthy period of the year was from March to June for endoparasites control, however, in the months of September and December the animals showed better performance measures.     

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.     

The haematological examination of canine blood samples received by post: the influence of delay in examination on red cell parameters

The mean packed cell volume (PCV) for canine blood samples received by post was significantly higher than that for fresh samples, at each haemoglobin value over the range 9 to 19 g/dl. As a consequence the mean corpuscular volume (MCV) and the mean corpuscular haemoglobin concentration (MCHC) also differed. Apart from one Hb value there was no significant difference in the mean red blood cell (rbc) count over the Hb range 6 to 14 g/dl. It is suggested that the normal values for the PCV and MCV should be 3 to 5% and 5 to 7 f 1 higher respectively for postal samples as compared to fresh samples while the MCHC should be about 3 to 4 g/dl lower.     

Stability of hematologic analytes in monkey, rabbit, rat, and mouse blood stored at 4°C in EDTA using the ADVIA 120 hematology analyzer

Background: The time from sampling to analysis can be delayed when blood samples are shipped to distant reference laboratories or when analysis cannot be readily performed. Objective: The objective of this study was to evaluate the stability of hematologic analytes in blood samples from monkeys, rabbits, rats, and mice when samples were stored for up to 72 hours at 4°C. Methods: Blood samples from 30 monkeys, 15 rabbits, 20 rats, and 30 mice were collected into EDTA‐containing tubes and were initially analyzed within 1 hour of collection using the ADVIA 120 analyzer. The samples were then stored at 4°C and reanalyzed at 24, 48, and 72 hours after collection. Results: Significant (P<.0003) changes in hematologic analytes and calculations included increased HCT and MCV and decreased MCHC and cell hemoglobin concentration mean (CHCM) at 72 hours and increased MPV at 24 hours in monkeys; increased MCV at 72 hours and MPV at 48 hours and decreased monocyte count at 24 hours in rabbits; increased MCV and decreased MCHC, CHCM, and monocyte count at 24 hours in rats; increased MCV, red cell distribution width, and MPV and decreased MCHC, CHCM, and monocyte count at 24 hours in mice. Conclusions: Although most of the changes in the hematologic analytes in blood from monkeys, rabbits, rats, and mice when samples were stored at 4°C were analytically acceptable and clinically negligible, the best practice in measuring hematologic analytes in these animals is timely processing of blood samples, preferably within 1 hour after collection.     

Pomegranate enriched diet enhances the hematology, innate immune response, and disease resistance in olive flounder against Philasterides dicentrarchi

Olive flounder, Paralichythys olivaceus fed with pomegranate enriched diet and challenged with or without Philasterides dicentrarchi had a significantly higher white blood cell (WBC) count on weeks 2 and 4 than the infected group fed with non enriched diet (standard diet). Similarly the red blood cell (RBC) counts did not significantly change in control and treated fish on weeks 1 and 2. It was significantly increased in treated fish on week 2 when compared to the control. In both the groups the hemoglobin (Hb) and hematocrit (Ht) levels significantly increased on weeks 2 and 4. The mean corpuscular volume (MCV) did not significantly change at any time in both groups whereas mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) increased significantly on week 4 in the treated group. The leukocytes such as lymphocytes (Lym), monocytes (Mon), neutrophils (Neu), and biochemical parameters such as total protein (TP), glucose (GLU), and calcium (CAL) levels significantly increased in treated groups on week 2 or 4 as compared to the control. The scuticocidal activity and respiratory burst activity were significantly enhanced in treated groups with or without parasite on weeks 2-4. However, the serum lysozyme activity was significantly enhanced from weeks 1 to 4. The protective response in terms of cumulative mortality was low in groups fed with enriched diet against parasite when compared to control. Therefore, we suggest that pomegranate enriched diet following challenge with P. dicentrarchi restores the altered hematological and biochemical parameters, and improves the innate immune system in olive flounder against P. dicentrarchi.     

Studies on some paraclinical indices on intoxication in horses from freshly cut Jimson weed (Datura stramonium)-contaminated maize intended for ensiling

Monitoring of changes in some blood laboratory parameters in 34 horses after ingesting freshly harvested maize that was to be used for ensiling, heavily contaminated with young Datura stramonium plants, is described. For a 7-day period the following parameters were monitored: haemoglobin content (HGB), red blood cell counts (RBC), white blood cell counts (WBC), haematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), differential white cell counts (DWC), erythrocyte sedimentation rate (ESR), protein fractions, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), total bilirubin (TB), direct bilirubin (DB), blood glucose (Glu), total protein (TP), globulin (Glob) and albumin (Alb). The intoxication was accompanied by erythrocytosis, leukocytosis, regenerative left shift neutrophilia, lymphopaenia, eosinopaenia, increased haematocrit values, low erythrocyte sedimentation rate, hyperglycaemia, bilirubinaemia, hypoproteinaemia and increased activity of AST and LDH. No changes occurred in the mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), albumin, globulin and globulin fractions (alpha 1, alpha 2, beta 1, beta 2 and gamma). The blood parameters returned to normal between post-intoxication days 2 and 5. The observed changes in clinical chemistry indices could be used in the diagnosis, differential diagnosis and prognosis of Jimson weed intoxication.     

果寡糖对固始鸡血液生理指标的影响

本试验旨在研究不同添加剂量的果寡糖对固始鸡血液生理指标的影响,并确定果寡糖的最佳添加剂量。选用1日龄固始鸡公雏150只,随机分成5个处理组,1个为对照组,其余4个为试验组,对照组不加果寡糖,其他4个组的果寡糖添加水平分别为3、5、7mg/kg和9mg/kg。测定红细胞压积(PCV)、血红蛋白(Hb)含量、红细胞数量、白细胞数量、平均红细胞体积(MCV)、平均红细胞血红蛋白含量(MCH)和平均红细胞血红蛋白浓度(MCHC)等指标。试验结果表明:1)21和42日龄时,果寡糖试验组的红细胞压积、血红蛋白含量、红细胞数量和白细胞数量均显著高于对照组(P<0.05);与对照组相比,试验组的MCH和MCHC均略有升高,并且可以显著提高MCHC(P<0.05);2)日粮中添加5mg/kg果寡糖对提高红细胞压积、血红蛋白含量、红细胞数量、白细胞数量、MCH和MCHC具有最佳效果。     

Dynamics of basic hematologic values in ewes during the course of a year

Basal hematological values were studied in ten primiparous ewes of Merino breed at 15 time intervals in the period from birth to the last decade of the next gravidity. The mean erythrocyte counts ranged from 6.5 to 10.3 T . l-1, hemoglobin content from 101.3 to 121.3 g per l, hematocrit value from 0.32 to 0.37 1 per l, mean corpuscular hemoglobin concentration from 29.97 to 34.22 g per dl, mean corpuscular hemoglobin from 11.17 to 16.61 pg, corpuscular volume from 35.03 to 55.37 fl. The mean leucocyte counts were from 4.98 to 9.93 G . l-1, with 25.8 to 60.5% neutrophil granulocytes with segmented nuclei, 0.1 to 2.6% neutrophil granulocytes with rodlike nuclei, 0.8 to 8.7% eosinophil granulocytes, 0.0 to 0.33% basophil granulocytes, 30.3 to 71.2% lymphocytes and 0.4 to 4.5% monocytes. The quality of red blood component was not negatively influenced by a high degree of gravidity. In the time of parturition, neutrophil granulocytes highly dominated over the other types of white blood cells; the counts normalized since the seventh day post partum. Although statistically significant differences were calculated for some time intervals, the values were within the physiological limits.     

Investigations of anemia of male rearing calves. 1. Reference conditions and anemia frequency

In a longitudinal investigation (3 points of time n = 214, 206 resp. 202) the hemoglobin quota (Hb), the hematocrit (Hct) resp. the average corpuscular hemoglobin concentration (MCHC) were analysed at male calves receiving semi-liquid feed in the transitional period from pre-ruminal to ruminal digestion (56d). Breed, live weight development, consumption of milk, concentrated feed resp. dried forage, diseases of the calves as well as the father and the milk yield resp. the lactation age of the mother were registered as reference conditions. The percentage of calves with an Hb less than 10.5 g/dl was at the three points of time 50.00%, 86.41% resp. 41.58%, of calves with an Hct less than 33,5% it was 43.46%, 66.02% resp. 31.68% and of calves with an MCHC less than 30.5 g Hg/dl erythrocytes 51.87%, 76,21 resp. 47,03%. 21.50%, 33.50% resp. 4.46% of all test animals even had an Hb of less than 8.5 g/dl.     

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   

Hematology in sika deer (Cervus nippon yesoensis Heude, 1884)

Blood samples were taken from 78 wild and 21 farmed sika deer (Cervus nippon yesoensis) using ketamine-xylazine sedation during their excited (82 deer) and resting (17 deer) states. Red cell count (RBC), hemoglobin (Hb), packed cell volume (PCV) and mean corpuscular volume (MCV) were significantly higher and mean corpuscular hemoglobin concentration (MCHC) was lower in excited deer than in resting deer. There was no significant difference in total leukocyte count (WBC) between excited and resting wild males, while a marked increase of WBC with neutrophilia was observed in excited wild females. RBC and PCV were significantly higher and MCH was lower in excited males than in excited females. In wild deer, WBC was significantly higher in females than in males, but there was no significant difference in WBC between farmed males and females. Sex differences in the hematological parameters were not observed in fawns (10 months).     

Biochemical and hematological reference ranges for Amazon freshwater turtle, Podocnemis expansa (Reptilia: Pelomedusidae), with morphologic assessment of blood cells

Blood parameters are useful to measure physiological disturbances in chelonians. Thus they can provide important information for the diagnosis and prognosis of diseases. The aim of this paper was to determine the reference range of plasma glucose, total protein, triglycerides, cholesterol and urea levels, as well as hematocrit, hemoglobin, red blood cell, thrombocyte and white blood cell counts for healthy Podocnemis expansa (Schweigger, 1812), bred in a turtle farm in the Amazonas State, Brazil. Plasma glucose, hemoglobin, mean corpuscular volume (MCV), lymphocytes and heterophils were the parameters with the smallest variations. Significant (p < 0.001) correlations between red blood cells count and hematocrit and hemoglobin concentration were found. Turtle P. expansa had lymphocytes, azurophils, heterophils, eosinophils and basophils with morphologic features similar to the ones of others turtles species. No investigated blood parameter was influenced by sex. In further studies, the established reference ranges might be useful for the health assessment of this turtle species.     

Hematologic values in calves during the first 6 months of life

BACKGROUND: Age-related changes in hematologic values are known to occur in many species. Few published studies include repeated measurements of hematologic parameters in calves during the first months of life. OBJECTIVE: The aim of the present study was to monitor hematologic values by sequential measurements from birth to 6 months of age in 15 healthy calves of the Norwegian Red breed, and compare the results to reference intervals for adult, lactating dairy cows. METHODS: Fifteen clinically healthy calves were sampled every week during the first 5 weeks of life and every month thereafter until 6 months of age. Hematologic values were measured using the ADVIA 120 hematology system. Reference intervals were determined for 75 healthy adult cows of the same breed. RESULTS: Compared with adult reference intervals, the MCV was lower and the RBC count was higher in calves throughout the investigation period. Hemoglobin concentration stayed largely within the adult reference interval. Mean MCHC was lower than adult values for 5 weeks, then increased and reached adult values by weeks 10-12. The mean lymphocyte count for calves reached adult reference values at weeks 6-8, and the mean monocyte count increased steadily until weeks 14-16. For most leukocytes, interindividual variation was larger during the first 5-8 weeks of life. The mean platelet count for calves was higher than the adult reference interval until weeks 19-21 of age. CONCLUSIONS: Age-specific reference intervals for calves from birth to 6 month of age are needed for RBC count, MCV, MCHC, red cell distribution width, and platelet and lymphocyte counts.     

Haematological responses of repeated large volume blood collection in the horse

The haematological response of regular, repeated blood harvesting was investigated in 40 Thoroughbred and non-Thoroughbred horses that donate 8 litres of blood every 3 weeks for the purposes of commercial blood production. When this volume of blood was removed on five occasions over 12 weeks, no adverse effect on packed cell volume (PCV), haemoglobin (HB), and red blood cell count (RCC) was observed. Although PCV, RCC and Hb values decreased during the first week after blood collection, followed by a gradual increase in values until the next harvest time, all values remained within published reference ranges. Derived red cell indices [mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC)] also remained within reference range. We conclude that the removal of approximately 8 litres of blood (approximately 16 ml kg(-1)or 20 per cent of blood volume for a 500 kg horse) from blood donor horses every 3 weeks allows time for adequate recovery of haematological variables and does not result in adverse haematological changes.     

Iron Status and Erythrocyte Volume in Dogs With Congenital Portosystemic Vascular Anomalies

Microcytosis, hypochromasia, and low mean corpuscular hemoglobin are frequent hematologic abnormalities in dogs with portosystemic vascular anomalies (PSVA). The relationship of iron status to these abnormalities is unclear. We evaluated iron status and hematologic and biochemical parameters in dogs with congenital PSVA before (25 dogs) and after (11 dogs) partial ligation of the vascular anomaly. Serum iron concentration and total iron binding capacity were subnormal in 56% and 20% of dogs with PSVA, respectively. Transferrin saturation was normal in 68%, decreased in 20%, and increased in 12% of the dogs. Plasma ferritin concentration was either normal (56%) or high (44%), and was not associated with increases in ceruloplasmin concentration. Hepatic stainable iron was increased in 10 of 16 dogs. Mean corpuscular volume (MCV), mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were decreased in more than 60% of dogs with PSVA. Serum biochemical abnormalities included high bile acid concentration and alanine transaminase (ALT) and alkaline phosphatase (ALP) activities; and low urea, creatinine, cholesterol, and total protein concentrations. Serum iron concentration and clinical status (normal or PSVA) significantly influenced MCV ( P = .003 and P < .001, respectively), whereas age, ceruloplasmin, ferritin, cholesterol, bile acids, and total iron binding capacity did not. Partial ligation of PSVA was associated with resolution of clinical signs and the return to normal of iron status and all clinicopathologic abnormalities, except total fasting bile acid concentrations. These findings indicate that iron status is frequently abnormal in dogs with PSVA and that low serum iron concentration appears to be related to the development of microcytosis. The normalization of iron status and clinicopathologic abnormalities after treatment suggests that they are direct consequences of PSVA.