International Species Information System
Physiological Data Reference Values - 1999
edited by J. Andrew Teare, DVM

At ISIS we take reasonable precautions to ensure that the reference ranges provided on this disk are of the highest possible quality. We remove extreme outlying values and quality-check the information submitted in several ways. However, as it is not possible to individually review all the test results contained in the more than 100,000 blood sample records submitted by member institutions, the pooled data is technically provided to you on an AS IS basis. Some unlikely test values may have inadvertently been included in the calculations, leading to reference ranges for individual tests that experienced clinicians will recognize as implausible. However, we are confident that the vast majority of reference values provided on this disk will provide useful diagnostic assistance for interpretation of test results obtained at your institution.

Test results for blood samples, along with associated body temperature and weight information, have been submitted to the ISIS database by member institutions for almost 20 years. Originally, paper forms were used to submit results to the database. Starting in 1992, member institutions, using the MedARKS software to manage their medical records, gained the ability to submit records electronically and the paper submission system was discontinued. The database has grown by at least 5000 records annually since the switch to electronic submissions and participation by member institutions continues to grow. The database currently contains over 100,000 sample records, obtained from more than 1000 species and provides a unique collection of physiological information for analysis.

Publication on a CD-ROM started in 1998 and replaced the paper version of the ISIS Physiological Data Reference Values that was published in prior years. The 1999 disk contains almost 3000 pages of reference values derived from the database of hematology, blood chemistry, body temperature and body weight values that is maintained by ISIS. This edition contains reference pages for more species than any previous edition and there is substantially greater information available for many species presented in earlier editions. Although still quite limited in quantity, available information on blood levels of some hormones and vitamins is included. The 1999 edition also expands over previous editions by providing body weight information for mammal species in various age groups. All pages on the disk are linked through an index page that cross-references the species by both common and scientific name.

This CD-ROM contains thousands of pages written with HTML (HyperText Markup Language). This is the same language used to build the World Wide Web (WWW), which means that you can use your Internet web browser program to display and print the pages on this CD-ROM. Start your web browser program and use the "File" and "Open" menu options on your web browser to open the starting page for the CD-ROM (index.htm). If your web browser is properly registered with the Windows operating system, the process is even easier. Use File Manager or Windows Explorer to locate the index.htm file on the CD-ROM, double-click on the file name and your web browser program will start and automatically open that file.

Once the index.htm file is displayed, you simply click on the appropriate links until you get to the correct page of reference values. This is identical to the process used to navigate around the WWW on the Internet. If you want a printed copy of these values, the web browser will also allow you to print that page of reference values. Several web browser programs have been tested and any browser capable of displaying pages that were written with HTML 3.2 should function with this CD-ROM.

There are actually 2 volumes of reference values on this CD-ROM with a separate Species Index page for each volume. For the USA units book, the reference ranges are given in the conventional units used by most USA laboratories, while the International units book uses the standard international units that are most common throughout the rest of the world. The top of each page of reference values indicates whether it is from the USA units or the International units volume. The volumes are otherwise identical.

The first page of each volume is the Species Index page; an alphabetical list of all the species with reference values. All species are listed in the index by both the scientific and the common name (in English), a design that should make it easy to quickly locate the appropriate page of reference values. The Species Index page also provides links to 4 pages that provide information about ISIS, the Physiological Data Project, and this CD-ROM.

The scientific name of the species usually provides the easiest means to get to the appropriate page of reference values, but all pages are also cross-referenced by common name. You can get to any part of the Species Index by scrolling down the index page to locate the appropriate species, but with more than 2000 entries on this page, you will probably want to use the quick index navigation section at the top of the page. Clicking on any letter in this section will jump you to the start of that alphabetic section on the index page; a much faster process than scrolling down the page to that point.

Each entry on the Species Index page is a link to another page. Clicking on a species name will usually open the appropriate page of reference ranges. However, some links from the Species Index will show you a new page that provides links to several different pages of reference values for the specified species. When there are a sufficient number of samples in the ISIS database, additional pages of reference values have been calculated for various sex and/or various age categories. For a page that links to multiple pages of reference values, simply choose the set of reference values that is most appropriate for your needs and click on the link to display that page. Each page of reference values has a link back to the start of the index page or you can use the "back" function of your web browser to go back to the previous page that was viewed.

Example: Locate reference values for comparison to test results obtained on a 4-year-old, male American black bear.

• Start the web browser program and open the appropriate species index page (USA or International)
• Click on 'U' in the index navigation section and jump to the entries in the index that start with 'U'
• Click on the link to Ursus americanus
• Click on the link for 8 day to 5 year old, male bears
• To see reference values calculated from a larger set of samples, go back one page and then click on the link for males of all ages
• To see reference values for all black bears, go back one page and then click on the link for all ages and both sexes

A reference values page starts with a header section that identifies the species, the age and sex groups used for the calculations, and the type of units, followed by a table that contains the actual calculated reference ranges for various tests. Each row in the table contains the name of the test, the mean and standard deviation of sample results, the minimum and maximum values used to calculate that mean, the number of samples used to calculate the mean and, finally, the number of individual animals that were sampled.

Hematology tests are at the top of the table, followed by blood chemistry tests and body temperature at the bottom of the table. The number of rows in this table varies greatly between species and this is entirely a reflection of the information submitted to the ISIS database by member institutions. In general, there is an inverse relationship between average body size for a species and the number of tests on a reference page for that species (smaller animals yield smaller samples, which allow for fewer tests).

There are potential problems associated with calculating physiological reference ranges from a database assembled from multiple sources. Our member institutions use different methods to collect and handle the blood samples and different laboratories are used to process the samples. Generating the reference values includes a number of steps that are designed to minimize the impact of these potential problems.

First, ISIS provides feedback on submitted results to the member institutions. All records submitted to ISIS are automatically scanned for unusual values and a report to the submitting institution provides the institution with the opportunity to review any unusual values that were detected. When records are edited by the institution, the new values are used to update the ISIS database. To minimize the impact of an outlying value, inclusion in this publication requires that a species have at least 10 sample records in the ISIS database. To maximize the number of available records for a species, all subspecies designations are ignored for the purpose of calculating the reference ranges. Only samples from animals that are classified, by the submitting institution, as being in normal health are used in calculating reference ranges.

During the calculation of reference ranges, all entries in the ISIS database are further processed in a number of ways in an attempt to eliminate values that represent laboratory or data entry errors. Finally, reference ranges are calculated in a 2-step process from the results that have passed all the previous tests. In the first step, an initial mean and standard deviation are calculated. In the second processing step, results in the sample set that deviate from the initial mean by more than 3 standard deviations are discarded and a final set of reference values are calculated from the remaining test values. This final processing step is designed to help eliminate outlying values that usually represent data errors.

A large number of factors, beyond simply the health status of the animal, can influence test results obtained from an animal. In recognition of that fact, ISIS has begun to calculate for some species, reference values from various subsets of the available information. At the recommendation of the Information Resources Committee of the American Association of Zoo Veterinarians, the first subdivisions of the information have been along the lines of sex and age. Raymund F. Wack, DVM, who chaired that committee at the time, was instrumental in establishing many of the species age grouping used in this publication and we greatly appreciate his efforts.

When a species has at least 100 records in the ISIS database, in addition to the overall reference values calculated from all the sample results, separate pages of reference pages are calculated for various sex and age groups. The age divisions vary for different species, and are selected with the intention of dividing the samples into the broad age groups of neonatal, infant/juvenile, adult and aged animals. When dividing samples by sex, only samples obtained from known males or known females are included in the calculations. Separate pages are produced for each combination of age and sex divisions, a process that can produce as many as 15 pages of reference values for a single species. Clearly, a species must have a large number of samples in the database to produce a subset reference page with a significant number of samples. Currently, any subset reference page with results is included in this publication but the value of pages calculated from a small set of sample results will need to be judged by the person using this reference.

It is hoped that future editions will be able to provide reference values for other subsets of the available information, such as for samples collected with chemical restraint versus manual restraint, or animal fasting time and animal activity prior to sample collection.