Validation of the Coulter AcT Diff hematology analyzer for analysis of blood of common domestic animals

Abstract: The objective of this study was to compare and assess the agreement between the Coulter AcT Diff hematology analyzer (CAD) and the Bayer Technicon H1 (H1) using blood samples from 391 animals of 4 species. The H1 has been used in veterinary laboratories for many years. Recently, Coulter modified the CAD and added veterinary software for hematologic analysis of feline, canine, and equine samples. A comparison of hemograms from dogs, cats, horses, and cattle was made using EDTA-anticoagulated blood samples. Both instruments were calibrated using human blood products. Performance characteristics were excellent for most values. The exceptions were MCV in canine samples (concordance correlation of .710), platelet counts for feline and equine samples (.258 and .740, respectively), feline and bovine WBC counts (.863 and .857, respectively), and bovine hemoglobin (.876).     

Modification and evaluation of a multichannel blood cell counting system for blood analysis in veterinary hematology

A multichannel, semiautomated, blood cell counting system (Coulter Counter Model S550) was modified for use in veterinary hematology by increasing both the erythrocyte and leukocyte aperture currents to 225 V and 195 V, respectively, followed by calibration with human blood. It was evaluated by use of 350 samples from dogs, cats, horses, and cows. Values for leukocyte count, erythrocyte count, mean corpuscular volume, and hematocrit generated by the S550 were compared with values generated by an automated multichannel counter with histogram capability and other reference procedures when appropriate. Mean differences for values between S550 and reference values were less than calibration tolerance limits for the instrument. Correlation coefficients were excellent for all values of each species. To assess behavior of leukocytes of the different species with respect to the counting threshold, leukocyte size distribution histograms were generated for all samples analyzed on the S550. Means for mean leukocyte volumes in diluent and lysing reagents were 55.5, 56.6, 67.4, and 72.8 fl for dogs, cats, horses, and cows, respectively. Canine leukocyte counts, because of small leukocyte size, were an average of 14% less for 5 samples analyzed on the unmodified instrument, compared with analysis after increasing the leukocyte aperture current. Leukocyte threshold failures attributable to interfering particles, resulting in falsely high counts, were recognized in 14%, 10%, 8% and 0% of feline, bovine, canine, and equine samples, respectively. The magnitude of error in these samples averaged 5% for cows and dogs, but was considered not important. However, leukocyte counts of feline samples in this group averaged 44% falsely high.     

黄曲霉毒素对常见家畜的危害及防治

黄曲霉毒素诱发多种疾病,对养殖业造成很大的危害。因此,如何防治该疾病至关重要。本文就常见家畜所遭受黄曲霉茵毒素侵害及当前能采取的解毒措施进行了综述。     

三种抗原对家畜日本血吸虫病诊断价值的比较

以日本血吸虫基因重组抗原LHD-Sj23／pGEX、可溶性虫卵抗原（soluble egg antigen，SEA）及SEA经Sephadex G-200柱层析分离后得到的第一峰SEAl作为诊断抗原，应用ELISA检测人工感染日本血吸虫绵羊血清及自然感染日本血吸虫水牛血清。结果显示，三种抗原用于检测人工感染日本血吸虫绵羊血清的阳性符合率分剐为88．79％、98．15％、100％，阴性符合率均为100％；自然感染日本血吸虫水牛血清的阳性符合率分别为80％、80％、84％，阴性符合率分别为88．9％、93．3％、91．1％；三种抗原与伊氏锥虫病牛血清无交叉反应；检测感染日本血吸虫不同时间绵羊血清，发现感染6周后均被检出针对这三种抗原的特异性抗体，且SEA及SEAl在感染4周后即可检出特异性抗体。三种抗原的诊断效果差异不显著。     

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 spectrophotometric methods for ceruloplasmin measurement in pigs

Ceruloplasmin (Cp) determination could provide an objective measure of the health status of an animal and could be used as marker of animal health and welfare (Skinner, 2001) (Skinner, J. G., 2001. Special report. International standardization of acute phase proteins. Veterinary Clinical Pathology 30, 2-7.) but only manual methods have been reported to determine Cp concentrations in pigs (McCosker, 1961; Toussaint et al., 1995; Eckersall et al., 1996) (McCosker, P. J., 1961. Paraphenylenediamine oxidase activity and copper-levels in mammalian plasmas. Nature. 190, 887-889; Toussaint, M. J. M., Van Ederen, A. M., Gruys, E., 1995. Implication of clinical pathology in assessment of animal health and in animal production and meat inspection. Comparative Haematology International 5, 149-157; Eckersall, P. D., Saini, P. K., McComb, C., 1996. The acute phase response of acid soluble glycoprotein, alpha(1)-acid glycoprotein, ceruloplasmin, haptoglobin and C-reactive protein, in the pig. Veterinary Immunology and Immunopathology 51, 377-385). In the present study two automated methods based on the use of two different substrates for the determination of serum ceruloplasmin in pigs were developed, evaluated and compared. Both methods showed a good precision and detection limits, with no signs of inaccuracy and could be applied to biochemical autoanalyzers usually found in clinical laboratories using only minimal amounts of serum. Additionally the behaviour of Cp in experimental and clinical situations was studied showing an increase of around two fold after turpentine administration and significantly higher values in cases of pigs with inflammatory conditions when compared with healthy pigs.     

Size referenced electronic leukocyte counting threshold and lysed leukocyte size distribution of common domestic animal species

Using a single channel electronic cell counter and attached particle size analyzer, leukocyte size distribution histograms were determined on canine, feline, bovine, and equine blood diluted with chloride-based diluent and treated with a conventional stromatolysin. Histograms were usually unimodal, but a few were bimodal. Mean values for mean lysed leukocyte particle volume were 49.2, 51.1, 55.4, and 65.0 fl for canine, feline, equine, and bovine blood, respectively. From inspection of histograms, a lower threshold of 30 fl referenced to latex spheres was interpreted to be appropriate for counting leukocytes of these four species simultaneously. Debris below the threshold was seen in many samples and was usually separated from the leukocyte population by a valley touching the histogram baseline at the threshold channel. Debris resulted in a visually detectable threshold failure by extending considerably into the leukocyte size range in 9% of feline, 9% of canine, and 7% of bovine samples. It is recommended that careful establishment of the lower counting threshold will minimize frequency and severity of leukocyte count error associated with failure to exclude debris.     

Guidelines for euthanasia of domestic animals by firearms

All animals that are to be killed, whether for food, for humane reasons, or because they are homeless, must receive a quick and painless death. In some smaller communities, veterinary or humane society expertise may not be readily available to humanely kill stray and unwanted animals. An alternative that provides for a humane death for the animal is by shooting. The following guidelines are intended to assist persons who must perform this usually distasteful task; they contain recommended techniques that will help to ensure that any animals killed by shooting will die in a humane way.     

Comparison of two anesthetic protocols for feline blood donation

Objective To compare hemodynamic variables during, and recovery quality following, anesthesia for feline blood donation using intramuscular ketamine–midazolam–butorphanol (KMB) versus inhaled sevoflurane in oxygen (SEV). Study design Prospective blinded, randomized, crossover study. Animals Twenty healthy, client‐owned, mixed breed cats, aged 4–8 years, weighing 5.2–6.4 kg. Methods Cats were anesthetized with KMB for one donation and SEV for another. Heart rate (HR), respiratory rate (f_R), pulse quality, mucous membrane color, capillary refill time, arterial hemoglobin saturation with oxygen (SpO₂), and noninvasive arterial blood pressure (Doppler) were assessed by a blinded observer every 1 minute during collection. A nonblinded anesthesiologist delivered drugs and responded to hemodynamic changes. Each donation consisted of 55 mL of whole blood drawn via jugular puncture over 5–22 minutes. Donors received 60 mL subcutaneous lactated Ringer’s solution before recovery. Donors were monitored for a minimum of 4 hours post‐donation, before returning home. Owners, unaware of anesthetic protocol, completed a questionnaire regarding their cat’s behavior during the 24 hours following donation. Results Both protocols provided adequate restraint but were complicated by significant hypotension, requiring intervention in 16 (84%) SEV cats, and eight (42%) KMB cats. KMB cats experienced post‐procedure hyperthermia, with body temperatures >103.5°F. All animals responded to symptomatic therapy within 2 hours. Owners noted a significantly faster return to normal behavior at home following SEV. Conclusion All cats experienced hypotension, with many animals requiring intervention. There was no significant difference between protocols in incidence and severity of hypotension. The primary post‐procedure complication was hyperthermia with KMB. Clinical relevance As a result of the potential for hypotension during blood donation, intravenous (IV) access and blood pressure monitoring are recommended for all anesthetized donor cats, regardless of the anesthetic protocol. Post‐procedure hyperthermia is a risk with KMB, so temperature monitoring is recommended. Return to normal behavior is faster with SEV.     

Comparison of haematological values in restricted- and ad libitum-fed domestic fowls: red blood cell characteristics

1. A haematological study of the red blood cell characteristics in domestic fowls fed restricted and ad libitum diets was examined. The characteristics included Hb (haemoglobin), PCV (Packed Cell Volume), Rbc (Red blood cell count), MCH (Mean Cell Haemoglobin), MCV (Mean Cell Volume), MCHC (Mean Cell Haemoglobin Concentration) and reticulocytes. 2. The investigation showed that Hb, PCV, MCH and MCV were all reduced when broilers were fed a restricted diet. The number of Rbc's in these birds also increased significantly compared with control ad libitum-fed broilers. MCHC and reticulocyte numbers did not alter significantly. 3. It is proposed that some of the red cell characteristics may be restored to within "normal" ranges by food restriction. However, the results did show that there was a tendency to induce a microcytic normochromic anaemia in these restricted-fed birds.     

p53 protein expression in conjunctival squamous cell carcinomas of domestic animals

The expression of p53 protein was investigated in eight formalin-fixed, paraffin-embedded conjunctival squamous cell carcinomas of five horses and one cow, dog and cat each by an immunohistochemical procedure in order to evaluate protein overexpression. Anti-human p53 protein mouse monoclonal antibodies known to be cross-reactive with p53 protein of the animal species examined were used. Positive p53 nuclear immunostaining was detected in five equine, one bovine and one feline cases. Conversely, no p53 immunostaining was found in the only canine case examined. These results demonstrate a frequent p53 overexpression in conjunctival squamous cell carcinoma that could be related to UV-induced mutations of the p53 tumor suppressor gene.     

Values of acid-base equilibrium in the blood of various species of domestic animals]

By means of the Astrup equilibration method the values of the acid-base balance of the blood were determined in 104 cows, 99 horses, 100 pigs, 15 sheep, 20 goats, and in 101 dogs. The pH values of the blood, the partial pressure of CO2, the base excess, the base buffer, the standard bicarbonate, the actual bicarbonate, and the total CO2 were processed statistically and are presented in tables.