Relationship between colloid osmotic pressure and plasma protein concentration in cattle, horses, dogs, and cats.

The relationship between colloid osmotic pressure (COP) and protein concentration was investigated for purified proteins and plasma samples obtained from cattle, horses, dogs, and cats. At equivalent concentrations, bovine albumin exerted a COP that exceeded that of gamma-globulins by a mean factor of 4.4. Similar relationships between COP and protein were observed in the other species. Consequently, for a given total protein concentration, COP was dependent on the albumin/gamma-globulins ratio. A commonly used nomogram for estimating COP from protein concentration, the Landis-Pappenheimer equation, did not provide reliable results for plasma samples from these species.     

Evaluation of an in-house enzyme-linked immunosorbent assay for quantitative measurement of serum total thyroxine concentration in dogs and cats

OBJECTIVE: To compare serum total thyroxine (T4) concentrations obtained with an in-house ELISA and a validated radioimmunoassay (RIA). DESIGN: Laboratory trial. SAMPLE POPULATION: 50 canine and 50 feline serum samples submitted for measurement of total T4 concentration with the RIA; samples were selected to represent a wide range of concentrations (< 6 to 167 nmol/L). PROCEDURE: Results of the ELISA and RIA were compared by calculating correlation coefficients, examining linearity, determining bias and precision, and evaluating clinical interpretations. RESULTS: Correlation coefficients for results of the 2 methods were 0.84 for the canine samples and 0.59 for the feline samples. Examination of bias plots revealed large variations in ELISA results, compared with RIA results. For the feline samples, the ELISA consistently overestimated total T4 concentration obtained with the RIA. When results of the 2 methods were categorized (low, borderline low, normal, borderline high, or high), results were discordant for 24 (48%) and 29 (58%) of the canine samples and for 18 (36%) and 28 (56%) of the feline samples (depending on whether borderline high ELISA results were considered normal or high). Reliance on results of the ELISA would have led to inappropriate clinical decisions for 31 (62%) canine samples and 25 (50%) feline samples. The ELISA coefficients of variation for the pooled canine and feline samples were 18 and 28%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Substantial discrepancies between ELISA and RIA results for T4 concentrations were detected. Thus, we concluded that the in-house ELISA kit was not accurate for determining serum total T4 concentrations in dogs and cats.     

Validation of the Sysmex XT‐2000iV hematology system for dogs,cats, and horses. II. Differential leukocyte counts

Background: The Sysmex XT‐2000iV is a laser‐based, flow cytometric hematology system that stains nucleic acids in leukocytes with a fluorescent dye. A 4‐part differential is obtained using side fluorescence light and laser side scatter. Objective: The purpose of this study was to validate the Sysmex XT‐2000iV for determining differential leukocyte counts in blood from ill dogs, cats, and horses. Methods: Blood samples from diseased animals (133 dogs, 65 cats, and 73 horses) were analyzed with the Sysmex XT‐2000iV (Auto‐diff) and the CELL‐DYN 3500. Manual differentials were obtained by counting 100 leukocytes in Wright‐stained blood smears. Results: Leukocyte populations in the Sysmex DIFF scattergram were usually well separated in equine samples, but were not as well separated in canine and feline samples. Correlation among the Sysmex XT‐2000iV, CELL‐DYN 3500, and manual counts was excellent for neutrophil counts (r ≥.97) and good for lymphocyte counts (r ≥.87) for all three species. Systematic differences between the 3 methods were seen for lymphocyte and monocyte counts. The Sysmex reported incomplete differential counts on 18% of feline, 13% of canine, and 3% of equine samples, often when a marked left shift (>10% bands) and/or toxic neutrophils were present. Eosinophils were readily identified in cytograms from all 3 species. Neither the Sysmex nor the CELL‐DYN detected basophils in the 7 dogs and 5 cats with basophilia. Conclusions: The Sysmex XT‐2000iV automated differential leukocyte count performed well with most samples from diseased dogs, cats, and horses. Basophils were not detected. Immature neutrophils or prominent toxic changes often induced errors in samples from cats and dogs.     

Postmortem eyefluid analysis in dogs, cats and cattle as an estimate of antemortem serum chemistry profiles.

This study was carried out to determine the diagnostic usefulness of postmortem eyefluid analysis in estimating antemortem concentrations of serochemical constituents. A total of 31 cattle, 18 dogs and 22 cats were selected from routine elective euthanasia submissions to a diagnostic laboratory. For all cases, a biochemical profile, including determinations for electrolytes, glucose, urea, creatinine, enzymes, cholesterol, bilirubin, protein and osmolality was performed on antemortem serum, and postmortem aqueous and vitreous humors at 0 and 24 h incubation periods. The association between serum and postmortem eyefluid chemistry values was examined using simple linear regression. A strong correlation between serum and postmortem eyefluid urea and creatinine concentrations was demonstrated in the three species examined over a 24 h postmortem interval. We concluded that an accurate estimate of antemortem serum urea or creatinine can be made from the analysis of aqueous or vitreous fluid at necropsy. An estimation of antemortem serum electrolytes (including calcium in cattle) cannot be made with a high degree of accuracy due to the amount of variability in the relationship between serum and eyefluid electrolyte values. For large molecules such as proteins, enzymes, cholesterol and bilirubin there was very poor correlation between serum and eyefluid values.     

Validation of the Sysmex XT‐2000iV hematology system for dogs,cats, and horses. I. Erythrocytes,platelets, and total leukocyte counts

Background: The Sysmex XT‐2000iV is a laser‐based, flow cytometric hematology system that has been introduced for use in large and referral veterinary laboratories. Objective: The purpose of this study was to validate the Sysmex XT‐2000iV for counting erythrocytes, reticulocytes, platelets, and total leukocytes in blood from ill dogs, cats, and horses. Methods: Blood samples from diseased animals (133 dogs, 65 cats, and 73 horses) were analyzed with the Sysmex XT‐2000iV and the CELL‐DYN 3500. Manual reticulocyte counts were done on an additional 98 canine and 14 feline samples and manual platelet counts were done on an additional 73 feline and 55 canine samples, and compared with automated Sysmex results. Results: Hemoglobin concentration, RBC counts, and total WBC counts on the Sysmex were highly correlated with those from the CELL‐DYN (r≥0.98). Systematic differences occurred for MCV and HCT. MCHC was poorly correlated in all species (r=0.33–0.67). The Sysmex impedance platelet count in dogs was highly correlated with both the impedance count from the CELL‐DYN (r=0.99) and the optical platelet count from the Sysmex (r=0.98). The Sysmex optical platelet count included large platelets, such that in samples from cats, the results agreed better with manual platelet counts than with impedance platelet counts on the Sysmex. Canine reticulocyte counts on the Sysmex correlated well (r=0.90) with manual reticulocyte counts. Feline reticulocyte counts on the Sysmex correlated well with aggregate (r=0.86) but not punctate (r=0.50) reticulocyte counts. Conclusion: The Sysmex XT‐2000iV performed as well as the CELL‐DYN on blood samples from dogs, cats, and horses with a variety of hematologic abnormalities. In addition, the Sysmex detected large platelets and provided accurate reticulocyte counts.     

A questionnaire on the health, management, and performance of cow-calf herds in Québec.

Questionnaires were mailed to 520 cow-calf producers in Québec in order to compare management practices and herd performance according to herd size (small: < 40 females, or large: > or = 40 females) and in 4 geographic areas for the 1995 calving season. Owners of large herds adopted management practice and preventive measures more often than did owners of small herds. Average calving and weaning rates were 95% and 87% respectively. Average perinatal and preweaning mortality rates were between 4.9% and 5.6%. A greater percentage of owners with large herds than owners of small herds reported diarrhea and pneumonia problems. Among large herds, the number of herds experiencing pneumonia and calf mortality associated with diarrhea tended to be higher in areas of the northwest. Calf mortality due to pneumonia was higher in the northeast. No regional variation was found among small herds. Further research is needed to identify diseases risk factors.     

Latex agglutination test: a simple, rapid and practical method for bovine serum CRP determination.

A semi-quantitative latex agglutination test for bovine serum CRP levels has been established by mixing diluted serum (or diluted standard serum) with a 1% latex suspension containing 0.489 micron latex particles coated with affinity-purified antibody at a ratio of 20 micrograms/mg latex. The agglutination was performed on a glass slide in a moist chamber at room temperature with 45 min. incubation. This test is reliable, reproducible and the results correlate with those of the single radial immunodiffusion (SRID) test. The effect of low temperature storage on CRP concentration revealed a 30% degradation of CRP during 2 years storage at 4 degrees C. The possible role of EDTA addition to prevent a decrease in serum CRP concentration by freezing and thawing is also discussed.     

Effects of xylazine administration on serum amylase, pancreas-specific isoamylase and pancreatic polypeptide in normal dogs.

Changes in serum total amylase, pancreas-specific isoamylase and pancreatic polypeptide activities were measured in six dogs following multiple intramuscular injections of xylazine at 0.5 mg/kg of body weight. The activities of those analytes did not change over 24 hours of study.     

Effects of hyperlipemia on radioimmunoassays for progesterone, testosterone, thyroxine, and cortisol in serum and plasma samples from dogs

Hyperlipemic serum and plasma samples often are received by clinical laboratories for endocrinologic analysis by radioimmunoassay. We designed a study to determine what effect, if any, hyperlipemia has on estimation of lipid-soluble hormone concentrations determined by solid-phase radioimmunoassays. Progesterone, testosterone, thyroxine, and cortisol concentrations were determined in canine plasma and serum with various degrees of lipemia. Samples of serum, heparinized plasma, and EDTA-treated plasma were obtained from blood collected from 4 female and 4 male Beagles by use of evacuated tubes. To induce hyperlipemia in vitro, IV fat emulsion was diluted in deionized water to produce 0 (water only), 33, 67, or 100% mixtures. Twenty microliters of each mixture then was added to the subsamples of serum and plasma from each dog. Hormone concentrations were determined, using validated radioimmunoassays. Triglyceride concentrations were determined by enzymatic assay. Addition of IV fat emulsion in vitro was an accurate and reproducible means of altering triglyceride concentrations in the samples. Triglyceride concentrations as high as 700 mg/dl had no effect on radioimmunoassays for progesterone, testosterone, and thyroxine in serum, heparinized plasma, or EDTA-treated plasma. Addition of 100% (but not 33 or 67%) fat emulsion reduced the mean cortisol concentration in heparinized plasma by 12% (P less than 0.05). This severe hyperlipemia did not affect quantification of cortisol in serum or EDTA-treated plasma.     

Effects of treatment with polysulfated glycosaminoglycan on serum cartilage oligomeric matrix protein and C-reactive protein concentrations, serum matrix metalloproteinase-2 and -9 activities, and lameness in dogs with osteoarthritis

OBJECTIVE: To investigate the effects of polysulfated glycosaminoglycan (PSGAG) treatment on serum cartilage oligomeric matrix protein (COMP) concentration, matrix metal-loproteinase-2 (MMP-2) and -9 (MMP-9) activities, C-reactive protein (CRP) concentration, and lameness scores in dogs with osteoarthritis. ANIMALS: 16 dogs with osteoarthritis and 5 clinically normal dogs. PROCEDURES: Dogs with osteoarthritis had a history of chronic lameness, and osteophytes were observed on radiographic evaluation of the affected joint. Polysulfated glycosaminoglycan was administered IM twice a week for a total of 8 treatments to all dogs with osteoarthritis and to clinically normal control dogs. RESULTS: Lameness scores after PSGAG treatment in osteoarthritic dogs improved in 12 of the 16 dogs. Serum COMP concentrations in osteoarthritic dogs were significantly higher than in control dogs before treatment. Lameness scores in osteoarthritic dogs decreased significantly after treatment, compared with before treatment. Lameness scores of 9 dogs with hind limb lameness improved significantly after treatment; these dogs had corresponding decreases in serum COMP concentrations. After treatment, serum COMP concentrations and lameness scores of 7 dogs with forelimb lameness remained high and were significantly higher than those of dogs with hind limb lameness. Serum MMP-9 activities of dogs with forelimb lameness were significantly higher than in dogs with hind limb lameness after treatment. CONCLUSIONS AND CLINICAL RELEVANCE: IM administration of PSGAG inhibited COMP degradation in dogs with osteoarthritis. Results indicate that decreases in serum COMP concentrations might be related to improvement in lameness after PSGAG treatment.     

Effects of the supplementation with an high‐polyphenols extra‐virgin olive oil on kinetic sperm features and seminal plasma oxidative status in healthy dogs

The aim of this work was to evaluate the effects of the supplementation of two extra‐virgin olive oils (EVOO) having different polyphenols content, on canine spermatozoa kinetic parameters and seminal plasma oxidative status. The study was conducted on 12 clinically healthy dogs of different breeds (2–7 years, 5–48 kg of body weight) divided into two groups: an experimental group supplemented with EVOO (Coratina cultivar) high in polyphenols (H‐P) and a control group fed EVOO (Cima di Bitonto cultivar) low in polyphenols (L‐P). The oil was daily administered per os (1 ml/3 kg BW) before meal. Semen collection was made twice at 15 days distance (D0₁ and D0₂) and then at 30 (D30), 60 (D60) and 90 (D90) days. Semen concentration and kinetic parameters were measured using computer‐assisted sperm analysis (CASA) system to evaluate: sperm total count, sperm motile (MOT%), progressive motility (PROGR%) and its fractions, straight‐line velocity (VSL, μm/s), curvilinear velocity (VCL, μm/s), average path velocity (VAP, μm/s), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), straightness (STR%) and linearity (LIN%). On seminal plasma, reactive oxygen species (ROS) and biological antioxidant potential (BAP) were tested. From findings, no differences were found for sperm MOT, VSL, VCL, VAP, ALH, BCF, STR, LIN and BAP. A gradual enhancement of PROGR% was observed in H‐P group (p < .01). The ROS levels were higher in dogs H‐P compared to the other group (p < .05). In conclusion, our results highlight the positive effects of EVOO polyphenols on sperm PROGR% in healthy dogs.     

Effects of Gn-RH on blood serum hormone concentrations, ovulation rates and embryo production in lactating cows treated with PMSG.

The effects of gonadotrophin releasing hormone injection into pregnant mare serum gonadotrophin treated cows on serum levels of luteinizing hormone, estradiol-17 beta and progesterone and ovulation rates was evaluated in 20 cows. Pregnant mare serum gonadotrophin treatment does not always induce superovulation as was shown in this study. Luteinizing hormone levels reached peak concentrations at 1.0 h and remained significantly (P less than or equal to 0.05) elevated at 2.0 h, 3.0 h, 4.0 h, and 7.0 h after the first gonadotrophin releasing hormone injection. Progesterone levels in the gonadotrophin releasing hormone treated group were significantly (P less than or equal to 0.05) higher than in the controls on the third and fourth days following injection. A significant correlation (r = 0.58-0.72) was noted between the number of corpus luteum and progesterone levels on each day between day 2 and day 7. More embryos were recovered (46 vs 26) from the ten treated than from the ten control cows.     

Effects of estrus and exogenous estrogen on circulating neutrophils and milk somatic cell concentration, neutrophil phagocytosis, and occurrence of clinical mastitis in cows.

In a study involving 56 quarters (14 cows), it was seen that standing estrus did not affect circulating neutrophil and milk somatic cell concentrations, neutrophil phagocytosis, milk production, or occurrence of clinical mastitis. The subcutaneous injection of 17beta-estradiol (E2) (0.05 mg/kg of body weight 2 times daily for 2 consecutive days) did not affect neutrophil phagocytosis or milk somatic cell values. However, a significant increase in circulating neutrophils and a significant decrease in milk production were observed. The injection of E2 was followed by clinical mastitis in 4 uninfected quarters, in 7 quarters infected with Corynebacterium bovis, and in 1 quarter infected with Streptococcus uberis and Escherichia coli.