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.     

Erythrocyte macrocytosis in feline leukemia virus associated anemia

Using erythrocyte volume distribution histograms (erythrograms), erythrocyte macrocytosis and anisocytosis were quantitated in 139 cats tested for feline leukemia virus group-specific antigen. Feline leukemia virus-negative cats with non-regenerative anemia or normal packed cell volumes had normal mean corpuscular volume values. Uninfected cats with regenerative anemia had prominent significantly increased macrocytosis and anisocytosis (p less than 0.01). Ninety percent of 62 feline leukemia virus-positive cats had altered erythrograms. Thirty-three feline leukemia virus-positive cats with non-regenerative anemia had marked macrocytosis. Their mean corpuscular volume values (mean 60 fl +/- 2 fl standard error, reference range of 37-49 fl) were significantly greater than those of feline leukemia virus-negative cats except for those with regenerative anemia. Feline leukemia virus-positive, non-anemic cats had significantly increased mean corpuscular volume values of intermediate magnitude. Nine adult cats experimentally infected with feline leukemia virus developed non-regenerative anemia with significant increases in mean corpuscular volume and anisocytosis. However, the macrocytosis observed in these cats was considerably less than in naturally occurring feline leukemia virus-positive cats with non-regenerative anemia. These observations indicate there are events in the pathogenesis of feline leukemia virus-associated anemia other than simple erythroid hypoplasia. We suggest that hemolysis and erythrocyte regeneration occur before erythroid hypoplasia and may partially account for macrocytosis observed in the face of non-regenerative anemia.     

Hematologic features of iron deficiency anemia in llamas.

Iron deficiency anemia was identified and characterized in three 14 to 29-month-old male llamas (llama Nos. 1-3) from separate herds in Colorado. The identification of iron deficiency anemia was based on hypoferremia (serum iron = 20-60 micrograms/dl), erythrocytic features, and hematologic response to iron therapy. The anemia was moderate and nonregenerative and characterized by erythrocyte hypochromia, microcytosis (mean cell volume = 15-18 fl), and decreased mean corpuscular hemoglobin concentration (36.0-41.0 g/dl). Morphologic features unique to llamas with iron deficiency anemia included irregular distribution of hypochromia within erythrocytes and increased folded cells and dacryocytes. The cause of iron deficiency was not determined. The llamas were treated with various doses and schedules of parenteral iron dextran. Two of the llamas were monitored for up to 14 months after the start of iron therapy and experienced increases in hematocrit and mean cell volume values. In one llama, progressive replacement of microcytic cells with normal cells was visualized on sequential erythrocyte volume distribution histograms following iron therapy.     

Volume-controlled bronchopulmonary lavage of normal and pneumonic calves

Saline bronchopulmonary lavage of the right lung of 16 anesthetized calves was performed using a single-lumen cuffed endotracheal tube. The initial volume of saline introduced was based on the functional residual capacity (FRC) of the right lung lobes as determined from the proportional weights of the right (58% of total FRC) and left (42% of total FRC) lung lobes. Calves were divided into "pneumonic" and "normal" groups based on clinical signs. Five sequential washes were done on each calf. There was no difference in the percentage of total lavage fluid volume recoverable between normal (83.8 +/- 4.2%) and pneumonic (81.1 +/- 8.2%) calves. Cell yield in the initial wash was consistently greater than in subsequent washes for both normal (12.7 +/- 6.6 X 10(6) cells/kg body weight) and pneumonic (58.1 +/- 37.6 X 10(6) cells/kg body weight) calves, and constituted 62.0% (normal) and 75.4% (pneumonic) of the total recoverable cell yield. Total cell yields were higher (P less than 0.05) in pneumonic calves, primarily due to neutrophil leukocytes (PMN). Neutrophils constituted 53.7 +/- 25% of the total cell yield in the pneumonic calves, but only 12.3 +/- 9.5% in the normal calves. The pulmonary alveolar macrophage (PAM) was the major recoverable cell in normal calves (85.7 +/- 8.7% of total lavage cells). Macrophages constituted a smaller (42.9 +/- 23.5) percentage of the total lavage cells in the pneumonic group due to increased PMN numbers. Viability of recovered cells from the pneumonic calves (91.5 +/- 4.8%) was lower than for the normal calves (94.1 +/- 2.5%), but the difference was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)     

Changes in circulating equine erythrocytes induced by brief, high-speed exercise

Five horses were exercised at 10m/sec at a 3 degree incline for 2 mins. Packed cell volume, erythrocyte count, haemoglobin concentration, mean corpuscular volume, plasma protein, total white cell count and lymphocytes increased significantly in blood samples taken after exercise, compared with those taken before exercise; but mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration decreased. Erythrocytes were more resistant to osmotic stress after exercise, but their shape and degree of deformity were unaffected by exercise.     

3种雉科鸟类血液生理指标的比较研究

为了解勺鸡、雉鸡和石鸡血液生理参数的正常值及其特点,为人工饲养繁殖以及健康状况监测提供参考依据,采用常规方法,对人工饲养的3种雉科鸟类(勺鸡、雉鸡和石鸡)红细胞数、白细胞总数、白细胞分类计数、血小板数、血红蛋白含量、红细胞沉降率、红细胞体积及红细胞比容8项血液生理指标进行了测定。结果表明,雉鸡的血小板明显高于勺鸡和石鸡(P<0.05);其它7项血液生理指标3种鸟之间差异不显著(P>0.05)。     

Reference ranges for hematologic and serum biochemical values in llamas (Lama glama)

Hematologic and serum biochemical values were determined in 174 llamas of all age groups and both sexes from ranches in California and Nevada. Compared with hematologic values for horses and cattle, llama erythrocytes were more numerous (10.1 to 17.3 x 10(6)/microliters), but the PCV was lower (25 to 45%) because the smaller elliptical cells pack tighter. The mean corpuscular volume was half that of horses and cattle (22 to 29.5 fl). The mean corpuscular hemoglobin concentration was higher (38.9 to 46.2 g/dl), and the mean corpuscular hemoglobin slightly lower (9.6 to 12.6 pg). Most serum biochemical values were similar to those of cattle and horses, with the exception of triiodothyronine (48 to 468 ng/dl) and thyroxin (9.8 to 30 micrograms/dl), which are up to 10 times higher than values for other domestic species.     

Retrograde flow of spermatozoa into the urinary bladder of rams

Retrograde flow of spermatozoa into the urinary bladder of rams during electroejaculation (EE) was examined. In experiment 1, semen and 4 consecutive samples of the urine released during the first post-EE micturition were collected once a week from 6 rams for 5 weeks during the nonbreeding season. The overall mean concentration per milliliter and the mean total number of spermatozoa in the urine ranged from 3.06 to 4.32 X 10(6) and from 80 to 2,865 X 10(6), respectively. The spermatozoal concentration in sequential urine samples was not different between samples, indicating that these spermatozoa had mixed with the urine before micturition. The percentage of the total number of spermatozoa displaced during EE, which flowed into the urinary bladder (retrograde flow), varied among rams (range 3.9% to 80%). The overall mean percentage of retrograde flow during the nonbreeding season was 28.3%. In experiment 2, a catheter was implanted into the urinary bladder of 6 rams (4 rams were from experiment 1), and semen was collected over 4 weeks during the subsequent breeding season. A urine sample was collected from the implanted catheter before EE. Immediately after semen collection, urine was collected by evacuating the bladder. The spermatozoal concentration in the pre-EE urine ranged from 0 to 1.3 X 10(6) (mean +/- SD, 0.17 +/- 0.38 X 10(6)) and was significantly (P less than 0.0001) lower than the spermatozoal concentration in the post-EE urine, which ranged from 1.10 to 22.55 X 10(6) (mean +/- SD, 9.46 +/- 11.30 X 10(6)).(ABSTRACT TRUNCATED AT 250 WORDS)     

Hematologic and serum protein reference values of the Octodon degus

Blood and serum from normal degus (Octodon degus) that ranged in age from 3 to 48 months were analyzed to determine reference hematologic and serum protein values. Both sexes were evaluated and were similar. The hematologic and serum protein values for males were: erythrocytes, 8.69 +/- 0.19 X 10(6) /microliter; packed cell volume, 42.1% +/- 0.59%; hemoglobin, 12.0 +/- 0.15 g/dl; leukocytes, 8.50 +/- 0.39 X 10(3)/microliter; neutrophil-to-lymphocyte ration, 40:60; and total protein, 5.70 +/- 0.20 g/dl. The hematologic and serum protein values for females were: erythrocytes, 8.94 +/- 0.16 X 10(6)/microliter; packed cell volume, 40.0% +/- 0.61%; hemoglobin, 11.7 +/- 0.17 g/dl; leukocytes, 8.20 +/- 0.36 X 10(3)/microliter; neutrophil-to-lymphocyte ratio, 40:60; and total protein, 5.62 +/- 0.18 g/dl. The hematologic and serum protein values for the degu were similar in some respects to values reported for guinea pigs and rats.     

Basic hematologic values in gilts of the Large White breed and their crosses with the Landrace breed

The basic haematological parameters (erythrocytes, haemoglobin, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, leucocytes, leucocyte type) were determined in 83 clinically relatively healthy gilts of the Large White breed and 85 gilts--crossbreds with the Landrace breed, at the age of five to seven months. The results were subjected to statistical processing. The erythrocyte counts are significantly higher in the crossbreds than in the gilts of the LW breed. The basic erythrocyte values, dependent on the number of erythrocytes, are significantly higher in the gilts of the Large White breed. The leucocyte counts correlate with those of the gilts of the same age; however, they are higher than in the adult sows. As a result of the evaluation of the leucocyte type, the gilts at the age of five to seven months were found to have a white blood picture of lymphocytic type. Further, a shift towards younger forms of cells of the granulocytic series was observed even in clinically relatively healthy animals.     

Experimental Salmonellosis in Guinea-pigs: Haematological and Biochemical Studies

Some haematological and biochemical parameters were studied in guinea-pigs infected intraperitoneally with Salmonella dublin 493 at 1×10⁶ viable cells per animal. The infected animals showed a rise in temperature within 24 h, followed by depression and loss of body weight. On the 15th day post infection, haematological studies revealed a significant increase in the total leukocyte count due to both lymphocytosis and neutrophilia, and a decrease in the total erythrocyte count and haemoglobin concentration. There was also a significantly higher mean corpuscular volume and lower mean corpuscular haemoglobin concentration, indicating a macrocytic hypochromic anaemia. The infection caused a significant increase in alanine aminotransferase activity and creatinine, blood urea nitrogen and globulin concentrations, and a decrease in albumin and triiodothyronine. There was no significant effect on serum total protein or on thyroxine, or in the activity of aspartate aminotransferase in the serum.     

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.     

Caprine hepatic lipidosis induced through the intake of low levels of dietary cobalt

Forty-one, 10-week-old newly weaned goats were randomly allocated into two groups, namely control (n=22) and treated (n=19). Kids in both groups were fed Rhodegrass hay ad libitum that contained < 0.1 mg/kg DM cobalt and 150 g/day of a commercially prepared ruminant concentrate that contained approximately 0.12 mg/kg DM cobalt. This diet provided the minimum daily requirement of cobalt as specified for sheep. The treated goats were supplemented with bi-monthly subcutaneous injections of 2000 microg of hydroxycobalamin. All goats were weighed and blood samples collected monthly for haematological, clinical biochemical and serum vitamin B12 analysis. After a 10-month experimental period the goats were slaughtered. The control animals exhibited significantly (P<0.05) lower weight gains, and had dry scruffy hair coats. In addition, there was a decline in erythrocyte counts, mean haemoglobin, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration. Controls also exhibited significantly (P<0.05) lower levels of total serum proteins and elevated levels of serum alkaline phosphatase compared to treated goats. Fourteen (63.6%) of the control goats developed pathology consistent with reported field cases of hepatic lipidosis associated with low liver levels of cobalt. Only one (5.3%) of the treated goats developed hepatic lipidosis. Contrary to previous reports that suggested that goats are less sensitive to low levels of dietary cobalt than sheep, it is apparent that this is not the case with Omani goats. This is the first report of the induction of hepatic lipidosis in goats due to feeding low levels of cobalt in their diet.     

Hematology analyzer comparison: Ortho ELT-8/ds vs. Baker 9000 for healthy dogs,mice,and rats

A Baker 9000 hematology analyzer (electronic impedance) was purchased to replace an Ortho ELT-8/ds analyzer (laser optics) due to discontinued technical support. An analytical comparison of hemograms from healthy dogs, rats, and mice was made from paired disodium ethylenediamine tetra-acetate anticoagulated blood samples. Both instruments were calibrated with human blood products, and the ELT-8/ds hematocrit (HCT) was calibrated to a spun packed cell volume (PCV) for each species. For Beagle dogs (n = 49), Baker 9000 mean platelet (PCV) counts had a negative bias of -89 X 10(3)/microliter when compared to ELT-8/ds values. Mean +/- standard error manual PLT counts compared well with Baker 9OOO values for dogs (n = 10): 369 +/- 28 vs. 367 +/- 27 X 10(3)/microliter; r = 0.93. For CD-1 mice (n = 44), Baker 9000 mean white blood cell (WBC) counts had positive biases of 1. 1 X 10(3)/microliter when compared to ELT-8/ds and 0.5 X 10(3)/microliter when compared to hemacytometer counts. Diluted microsamples using the predilution mode on the Baker 9000 compared well with undiluted samples for mice. For Sprague-Dawley rats (n = 70), Baker 9000 mean WBC, red blood cell (RBC), and PLT counts had absolute biases of 0.8 X 10(3)/microliter, -1.09 X 10(6)/microliter, and -357 X 10(3)/microliter, respectively, when compared to ELT-8/ds values. Baker 9000 RBC, WBC, and PLT counts from rats compared well with reference hemacytometer counts. The Baker 9000 HCT determination for rats had an absolute negative bias of 6% when compared to the ELT-8/ds values or spun PCV. The Baker 9000 required whole blood calibration to PCV for accurate determination of HCT for rats. The biases between analyzers may be due to inherent physical differences between the analytical methods and/or the calibration techniques.     

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.     

Evaluation of Citrate-Phosphate- Dextrose-Adenine as a Storage Medium for Packed Canine Erythrocytes

Packed canine red blood cells (RBCs) stored in the anticoagulant-preservative solution citrate-phosphate-dextrose-adenine (CPDA-1) were studied at 1, 10, 20, 30, and 40 days. The extracellular concentrations of potassium and sodium, erythrocyte mean corpuscular volume, and osmotic fragility increased during storage (P less than 0.05). There was a decrease in the pH, plasma concentration of glucose, and erythrocyte concentrations of 2,3-diphosphoglycerate (2,3-DPG) and adenosine-5'-triphosphate (P less than 0.05). Erythrocyte 2,3-DPG concentration decreased by 54% within the first 24 hours of storage (P less than 0.001). Posttransfusion viability (PTV) decreased from 90% on day 1 to 46% on day 40 (P less than 0.05). The PTV of the RBCs stored for 10 and 20 days complied with the Food and Drug Administration (FDA) standard. Although there are marked biochemical and hematologic changes in stored packed red blood cells (pRBCs), 20-day-old units may be expected to be of acceptable quality. The sharp decrease in 2,3-DPG concentration suggests a reduction in oxygen carrying capacity in erythrocytes stored as pRBCs. Hyperkalemia occurs during storage of pRBCs and does not appear to be associated with high intraerythrocytic potassium concentrations.     

Sizing of animal erythrocytes using sulfate based diluent

Sulfate based cell counting diluent and human erythrocyte size standards were evaluated for electronically sizing erythrocytes of common domestic species. Mean differences between calculated and human cell referenced electronic mean corpuscular volume values were 0, 0.4, 0.8, and 2.1 fl for blood of dogs, horses, cats, and cows, respectively. These differences were statistically significant only for the cat (p=0.029) and cow (p=0.0002). Electronic mean corpuscular volume was measured on multiple lots of human cell control material following calibration with human cells and cells of each of the four species. There were no significant differences between assigned assay values and direct measurements at each calibration (F=0.14, df=29). Sulfate based diluent, used on some automated cell counting systems, appears suitable for sizing animal erythrocytes and commercially available human cell standards are appropriate for calibration of certain systems used in veterinary hematology.     

Erythrocyte distribution in ducks

A study on erythrocyte distribution was performed on 10 healthy, nonstressed adult white Pekin ducks. Results indicated 2 populations of erythrocytes, with average mean corpuscular volumes of 128.37 fl/cell and 308.50 fl/cell. Variations in erythrogram patterns were evident over time, when comparing specimens from different ducks or the same duck. There were 5 patterns of cell number/volume distribution observed between the 2 cell populations when all ducks were studied. Females had a greater change than did males when population density and volume percentage comparisons were made on erythrocyte compartments.     

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   

Changes in subpopulations of lymphocytes in peripheral blood, and supramammary and prescapular lymph nodes of cows with mastitis and normal cows

Direct immunofluorescence (IF) and indirect IF techniques were employed to analyze the distribution of B and T lymphocyte populations in peripheral blood, and in supramammary (draining), and prescapular (non-draining) lymph nodes of cows with mastitis and normal cows. In the peripheral blood there was a significant decrease in the percent and absolute number of B lymphocytes in mastitic cows (n = 29; 17.1 +/- 10.2%; 3.4 +/- 2.7 X 10(5) cells/ml) as compared to normal cows (n = 38; 25.2 +/- 7.8%; 9.3 +/- 5.4 X 10(5) cells/ml). The percent T lymphocyte count in mastitic cows (71.2 +/- 7.1%) was slightly increased over that of normals (65.8 +/- 7.2%), although the absolute number of T lymphocytes was decreased in mastitic cows (1.49 +/- 0.91 X 10(6) cells/ml vs. 2.47 +/- 1.28 X 10(6) cells/ml). In the prescapular lymph node the percent of B lymphocytes, but not T or "null lymphocytes", decreased significantly in mastitic cows as compared to that of normals. The decrease, i.e. 32%, paralleled the 32.1% decrease found in peripheral blood B lymphocytes. In contrast, in the supramammary lymph node of mastitic cows, the percent B lymphocytes increased over that of normals (35.1 +/- 2.0% vs. 20.4 +/- 9.4%), whereas the percent T lymphocytes decreased to 54.5 +/- 2.8% compared to 70.7 +/- 3.5% in normal cows. There was no significant change in percent "null lymphocytes". The weight of prescapular lymph nodes did not change in mastitic cows when compared to that of normals. As a result, the estimated number of B lymphocytes, but not of T and "null lymphocytes", decreased.(ABSTRACT TRUNCATED AT 250 WORDS)