Prospective study of equine colic incidence and mortality.

A prospective study of one year was conducted on 31 horse farms to obtain population based estimates of incidence, morbidity and mortality rates of equine colic. Farms with greater than 20 horses were enrolled by randomly selecting horse owners from 2 adjacent counties of Virginia and Maryland. Descriptive information for 1427 horses was collected at the initiation of the study and updated at 3 month intervals. Time on the farm during the study was tabulated for each horse. When colic was reported by the owner, investigators visited the farm to obtain information about the colic. The crude incidence density rate of colic was 10.6 colic cases/100 horse-years, based on 104 cases/358,991 horse-days. The median farm specific incidence density rate was 7 cases/100 horse-years, and the range for individual farms varied from 0 to 30 colic cases/100 horse-years. A specific diagnosis was not made for 84 (81%) of colic episodes. Seventy colic episodes (67%) were treated by a veterinarian. Drugs were used in 83 (80%) colic episodes, and 78 (75%) of colic cases were mild, requiring no treatment or resolving after only one treatment. Four horses required colic surgery. Fourteen (13%) horses had more than one episode of colic during the year. Mortality from all causes of death was 2.5 deaths/100 horse-years, mortality rate for colic was 0.7 deaths/100 horse-years. Proportional mortality rate of colic, 28%, was higher than for any other cause of death. Horses less than age 2 years or greater than age 10 years had lower incidence than horses age 2-10 years. No difference in colic risk between genders was identified. Arabian horses had the lowest and Thoroughbreds the highest breed specific incidence rates. Horses used for eventing, or in training had a statistically significant higher incidence rate of colic compared to mature horses with no use (pets, retired, on pasture with no stated purpose). Horses used for lessons or with no use had the lowest incidence rates.

Prospective study of equine colic risk factors.

A 1 year prospective study was conducted on 31 horse farms to identify risk factors for equine colic. Farms were randomly selected from a list from 2 adjacent counties of Virginia and Maryland, USA. The association between colic and farm or individual horse risk factors related to management, housing, pasture, use, nutrition, health and events was first examined by univariate statistical analysis. Individually significant (P < = 0.25 for farm factors, P < = 0.10 for horse factors) variables were used in a stepwise multivariable forward logistic regression to select explanatory factors (P < = 0.05). Analysis was conducted at 2 levels: farm and individual horse with farm specified as a random effects variable. No farm-level variables were significant. Significant horse-level variables included: age, odds ratio (OR) = 2.8 for horses age 2-10 years compared to < 2 years; history of previous colic, OR = 3.6 relative to no colic; changes in concentrate feeding during the year (1 per year, OR = 3.6, more than 1, OR = 2.2) relative to no changes; more than 1 change in hay feeding during the year, OR = 2.1 relative to no changes; feeding high levels of concentrate (> 2.5 kg/day dry matter, OR = 4.8, > 5 kg/day dry matter, OR = 6.3) relative to feeding no concentrate; and vaccination with monocytic ehrlichiosis vaccine during the study, OR = 2.0 relative to no vaccination. Feeding a whole grain with or without other concentrate components reduced risk, OR = 0.4, relative to feeding no whole grain. Results of the study suggest that diet and changes in diet are important risks for colic in a population of horses on farms.

Prognosis for neonatal foals in an intensive care unit.

This study was conducted to develop an equation for the prediction of outcome in neonatal foals undergoing treatment in an intensive care unit (ICU). Fifty-three physical examination, historical, and clinicopathologic variables were analyzed from the records of 99 neonatal foals (< 14 days of age) treated in the neonatal ICU of the Equine Medical Center. The outcome was recorded and the results were categorized into either surviving or nonsurviving groups. The mean values for the 2 groups were compared, and variables that differed significantly between the two groups were retained and used to construct a logistic regression equation. Retained variables were heart rate, temperature, and neutrophil count. The predictive equation then was tested prospectively in 2 additional groups of foals from 2 separate ICUs. The predicted outcome was compared to the actual outcome, and performance variables were calculated. Sensitivity (.83), specificity (.87), negative predictive value (.72), and positive predictive value (.93) were determined for foals from one neonatal ICU; the sensitivity (.83), specificity (.44), negative predictive value (.44), and positive predictive value (.83) were lower for foals at a second, separate ICU.

Comparison of hematologic reference intervals between culture system and type of hybrid striped bass.

OBJECTIVE: To determine and compare hematologic reference intervals for hybrid striped bass from different culture systems and for 2 types of hybrid. DESIGN: Observational comparison study. ANIMALS: Clinically normal sunshine bass (reciprocal hybrid striped bass, female Morone chrysops X male M saxatilis) raised in high-density recirculating systems, sunshine bass raised in tanks with biofilters, and palmetto bass (original hybrid striped bass, female M saxatilis X male M chrysops) raised in tanks with biofilters. PROCEDURES: Hematologic reference intervals were determined for fish from the different production systems, following the National Committee for Clinical Laboratory Standards guidelines. Reference intervals from the 3 groups were compared. RESULTS: Reference intervals were significantly different between sunshine bass in the 2 culture systems and between sunshine and palmetto bass. Many of the differences were slight, but notable differences were observed. Sunshine bass in recirculating systems had higher total leukocyte, lymphocyte, neutrophil, and monocyte counts than did either hybrid in tanks. Palmetto bass had a greater number of neutrophils than monocytes, whereas sunshine bass had more monocytes than neutrophils. Additionally, palmetto bass had a lower PCV and hemoglobin value than did either group of sunshine bass. CONCLUSIONS: Separate reference intervals should be developed for hybrid striped bass in different culture systems and for different types of hybrids. CLINICAL RELEVANCE: Determining reference intervals for hybrid striped bass provides a tool to assess the health status of these fish.

Blood biochemical reference intervals for sunshine bass (Morone chrysops x Morone saxatilis) in three culture systems.

OBJECTIVE: To determine and compare biochemical reference intervals for sunshine bass (hybrid striped bass) from 3 culture systems. DESIGN: Observational comparison study. ANIMALS: Clinically normal sunshine bass (reciprocal hybrid striped bass, female Morone chrysops x male M saxatilis raised in high-density recirculating systems (80 g/L), low-density tanks (5 g/L) with biofilters, and cages (70 g/L) in a fresh water pond. PROCEDURE: Biochemical reference intervals were determined for fish from the different production systems following the National Committee for Clinical Laboratory Standards guidelines. Reference intervals from the 3 groups were compared. RESULTS: Reference intervals were significantly different between sunshine bass in the various culture systems. Though most of the differences in reference intervals were minor, fish in the high-density recirculating system had higher concentrations of total protein, albumin, globulin, creatinine, and phosphorus, and lower chloride values. There were no significant differences in glucose concentrations among the 3 groups of fish, and no differences in cortisol concentrations between fish in tanks and cages. CONCLUSIONS: Separate reference intervals should be developed for hybrid striped bass in different culture systems. CLINICAL RELEVANCE: Determining biochemical reference intervals for hybrid striped bass provides a tool to assess the health status of these fish.

The effect of temperature and water quality on antibody response to Aeromonas salmonicida in sunshine bass (Morone chrysops x Morone saxatilis).

The kinetics of the antibody response to Aeromonas salmonicida were determined in sunshine bass (hybrid striped bass: female Morone chrysops X male Morone saxatilis) acclimated to 10, 18, 24, 29 degrees C, and to 0.15 mg 1(-1) un-ionized ammonia and 200 mg 1(-1) nitrate levels. Temperature and water quality factors affected the immune response of sunshine bass. Temperatures of 10 degrees C and 18 degrees C decreased the magnitude and delayed the time of the antibody response to A. salmonicida. The antibody response was not affected at 29 degrees C, which is above the optimal temperature for sunshine bass. Elevated un-ionized ammonia concentrations of 0.15 mg 1(-1) also did not affect the antibody response. Elevated nitrate levels of 200 mg 1(-1), however, decreased the antibody response to the same extent as 18 degrees C water.

Reactivity to intradermal injections of extracts of house dust and housedust mite in healthy dogs and dogs suspected of being atopic.

Fifty dogs underwent intradermal allergy testing with housedust mite and house dust extracts, using concentrations recommended by the manufacturer. Twelve dogs (group I) were healthy dogs obtained from a pound; 12 dogs (group II) were healthy, privately owned dogs; 15 dogs (group III) were suspected of being atopic and had had multiple positive reactions to intradermal injections of allergens of specific trees, weeds, grasses, or molds; and 11 dogs (group IV) were suspected of being atopic, but only had had positive reactions to intradermal injections of housedust mite, house dust, and flea antigen extracts. Use of the concentrations of housedust mite and house dust extracts currently recommended for intradermal allergy testing resulted in false-positive reactions in 14 of 24 (58%) and 12 of 24 (50%) healthy dogs tested, respectively. Differences in number of dogs with positive reactions or grade of reaction to housedust mite or house dust allergens were not detected between groups of healthy dogs (groups I vs II), between groups of suspected atopic dogs (groups III vs IV), or between healthy dogs and dogs suspected of being atopic (groups I and II vs III and IV). Therefore, clinical importance of positive results of intradermal allergy testing of house dust or housedust mite allergens was equivocal for dogs suspected of being atopic. Threshold concentrations for intradermal allergy testing were determined in 24 healthy dogs (group I and II) by intradermal administration of 5 dilutions each of housedust mite extract and house dust extract.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunoglobulin M antibodies detected by enzyme-linked immunosorbent assay and radioimmunoassay in the diagnosis of cytomegalovirus infections in pregnant women and newborn infants.

Immunoglobulin M (IgM) antibodies were detected by a commercially available enzyme-Linked Immunosorbent Assay (ELISA) in 36 of 49 (73%) pregnant women with primary cytomegalovirus (CMV) infection. A positive ELISA-IgM result occurred in 10 of 13 patients (77%) assessed within 8 weeks of seroconversion. The sensitivity of the radioimmunoassay (RIA) to identify primary infection in pregnant women was comparable, 78% in general and 86% for women tested within 16 weeks of seroconversion. Of the 36 women with primary infection who had detectable IgM antibodies by ELISA, 25 (69%) were delivered of congenitally infected infants, whereas of the 13 with undetectable IgM antibodies, 7 (54%) transmitted the infection in utero. IgM antibodies were detected by ELISA in only 5 of 43 (11%) women who experienced a recurrence of CMV which either did or did not result in congenital infection. RIA was less likely to measure CMV-specific IgM in recurrent infection, inasmuch as 1 of 19 (5.2%) women with proven recurrent infection had detectable IgM antibody, giving RIA a better specificity for primary infection. Specific IgM antibodies were detected by ELISA in 42 of 61 (69%) babies congenitally infected with CMV and in 4 of 70 (5.7%) uninfected control newborn infants. The RIA was superior for diagnosis of congenital CMV infection, with a sensitivity of 89% and a specificity of 100%. The lower sensitivity of the ELISA-IgM occurred in the category of congenitally infected infants born to mothers with recurrent infection (43%), a group that is at the lowest risk of disease or to develop sequelae. This commercially available ELISA-IgM could be used in combination with a CMV-specific IgG test for monitoring women during pregnancy for primary infection.

IgM detection by ELISA in the diagnosis of cytomegalovirus infections in homosexual and heterosexual immunosuppressed patients.

A new commercially developed cytomegalovirus (CMV)-IgM ELISA was found to be sensitive and specific when compared with sucrose gradient fractionation of Ig classes in CMV antibody-positive and negative sera. The presence of CMV IgM in patients' sera correlated with positive virus isolation from circulating mononuclear blood cells and urine. Serial examinations of patients with primary or recent CMV infection revealed a typical sequence of IgM and IgG development. The frequency of CMV isolation declined as the concentration of IgM decreased and the IgG levels increased. Since the isolation of CMV from clinical specimens is a cumbersome procedure, we suggest that the IgM ELISA could provide rapid and valuable information on the presence of an active or reactivated CMV infection.