USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

General Introduction:

Normal pregnancy length can vary widely in the mare. Thus many nights can be spent waiting up for the mare to foal.

Physical signs of the mare's approaching readiness for foaling include an appropriate gestation length of greater than 320 days, udder enlargement with the presence of colostrum (milk), in the teats, waxing on teat ends and relaxation around the tail head, buttocks and lips of the vulva. While helpful, none of these signs are extremely accurate as a means of predicting when the mare will foal.

Recent studies of pre-foaling milk (mammary secretion) electrolyte changes have demonstrated an increased ability to predict foaling time. These electrolyte changes (especially with regard to calcium level) have also been shown to be related to the development of maturity of the foal in the uterus and its subsequent survivability (viability) following a normal delivery. This kit has been developed from years of extensive research and testing.

The intent is to assist you in determining when the mare is likely to foal based upon the kit's ability to detect changes in your mare's pre-foaling milk calcium level. It is a tool that, when used in an appropriate manner, will allow you to attend your mare's foaling without an excessive number of sleepless nights. The advantages of this kit include its accuracy and repeatability compared with other test kits (or test strips) available on the market, its ease of use, its quantitative (numerical) determination of the calcium carbonate level in each sample of pre-foaling milk tested and its economy.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

When to begin testing your mare:

Begin sampling and testing approximately 10 to 14 days in advance of your mare's expected foaling date (calculated as 335 to 340 days from her last known breeding date).

In mares with an unknown breeding date, testing should begin as soon as you note some udder enlargement and secretions can be obtained from the teats without undue effort. It is best to keep a close check on udder development on a daily basis and practice massage of the mare's udder and teats to allow her to get used to your presence in this area.

Once a day sampling is sufficient until you begin to get values of calcium that exceed 100 ppm. Then twice daily sampling is recommended. The more accurate assessment of your mare's readiness to foal will be a late afternoon or an evening sampling each day (as most mares foal at night).

Since a few mares do foal in the daytime, a morning sampling should not be neglected and is highly advisable when calcium values first exceed 125 ppm.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Testing Procedure:

Wipe the udder and teats with a clean, dry, soft paper towel prior to attempting to collect your sample. This reduces the amount of skin debris and dirt that might contaminate the sample, although such contamination will not alter the test result to any appreciable extent. This step is strongly recommended if the mare has been out in the weather and is wet. Your hands also should be clean and dry.

One to five mL (cc) of mammary secretion should be obtained per mare. It should collected in a clean manner by gently stripping a small amount from each teat using thumb and index or middle finger into a clean plastic test tube, or other sampling cup. The cup or test tube can be re-used if it is carefully rinsed with distilled water and then dried between uses. The sample should then be taken to a clean, dry and preferably warm area (for your comfort) for testing.

Use the syringe supplied in the kit to draw-up exactly one mL (cc) of the sample. Be sure that you do not have any air bubbles in the syringe barrel or tip, if you do, hold the tip of the syringe up, gently flick the tip with your finger to dislodge bubbles allowing them to go towards the syringe tip. Expel them by depressing the plunger. Then draw more sample into the syringe exactly to the one mL (cc) mark.

Place all the measured sample into the testing cup. Add exactly six mL (cc) of distilled water supplied in the kit. This dilution of the milk sample must be accurate.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Using the Strip Test:

One example of a water hardness strip test that has been used for this purpose is the Sofchek™ Test Strip. Once the above dilution has been accurately performed, simply dip one of these test strips into the diluted sample and swish for 1-2 seconds to be sure the pad at the bottom of the strip is wet.

Remove it, shake off the excess diluted milk sample from the tip and wait 15 seconds. Read it by comparing the color change to the side label of the Sofchek™ container. The pad may or may not change color dependent upon the concentration of calcium carbonate (ppm) it contains.

These strips tend to be useful to screen early changes, but do not respond accurately when the milk levels have greater than 120 ppm calcium carbonate. I therefore recommend using them up to this point (if desired) then switching to the FoalWatch™ kit.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Preparation and Use of FoalWatch™:

After the dilution step (above) is completed, then add one or two drops of the indicator dye solution to the diluted sample. (These instructions should be exactly the same as the product insert, except interpretation of the result, which is intended to be a direct read from the scale marked on the FoalWatch™ titret chamber.)

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Interpretation of Results:

In mares that have been evaluated by the FoalWatch™ test, there was a 54% probability that foaling would occur within 24 hours when the pre-foaling mammary secretion calcium first meets or exceeds 200 ppm.

There was an 84% probability that foaling would occur within 48 hours when pre-foaling mammary secretion calcium first meets or exceeds 200 ppm, and a 98% probability that foaling would occur within 72 hours when pre-foaling mammary secretion calcium first meets or exceeds 200 ppm.

The majority of mares foal within a short period of time when a value of 300 to 500 ppm is obtained. But not all mares can be expected to reach these higher values. For mares that had not yet reached or exceeded 200 ppm, there was a 98% probability that foaling would not occur within the next 24 hour period.

Note: The FoalWatch™ test does not claim to be 100% accurate in all mares. As with any biological system, exceptions are encountered, and no test can be expected to provide completely accurate and reliable results all of the time, in all situations. This is an aid to your foaling management program, and is not intended to guarantee a successful outcome in all mares.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Interference and Complications:

Some mares are resentful of being milked, especially if they are maiden (first-time foaling) mares. Standing to the left side of the mare and facing her tail, press your shoulder firmly against her chest, reach with your right hand first to her belly near the umbilicus and rub gently and progressively toward the udder.

Several attempts may need to be made to reassure the mare that you mean no harm. Make this a pleasurable experience for the mare, offer her some grain while collecting the sample. The more comfortable she is with you collecting her milk, the easier it will be for her to accept her new foal attempting the same procedure.

It is not unusual for maiden mares to fail to develop much of an udder prior to foaling. In which case your ability to obtain a sample for testing will be greatly hampered. The 'first milk' (colostrum) is typically a very thick, honey-colored, sticky secretion. This is an appropriate sample to recover as calcium levels will be detectable just as with more 'normal' appearing milk.

Mares that have been exposed to Fescue grass (specifically the Kentucky 31 variety) pastures contaminated by the fungus Acremonium Coephenophialum during the last 60-90 days of gestation may suffer from the toxins that are produced within the grass. Such mares very often fail to undergo normal udder development prior to foaling (and often even after), a problem referred to as agalactia. Without a sample for testing, this kit will be of little help to your management of such mares. Consult your veterinarian for prevention of this problem.

Since calcium contributes to the hardness of water, all precaution should be used to rinse all re-usable items exceptionally well with distilled water prior to drying. Use only distilled water (supplied or purchased from local stores) for all sample dilutions in the testing procedure.

Obtaining the small sample volume that is required for testing, on a once to twice daily basis, for the 10 to 14 days of average duration prior to foaling, does not deprive the foal of any significant amount of colostrum (or its antibody content) once it is born and begins to nurse. Many foals have been monitored during the research and development of this procedure, and in no case was a failure of passive transfer (inadequate colostrum consumption and passing of antibodies from the mare's milk to the foal) attributable to the sampling of pre-foaling mammary secretions. In like manner, the quality of the mare's colostrum (its content of antibodies) is not affected.

Mares that are prone to 'running milk' prior to foaling will do so whether they have been sampled for testing or not. Such mares are still at risk of losing too much colostrum prior to foaling and should be managed accordingly regardless of testing. Consult your veterinarian if you are not familiar with this problem.

The procedure of pre-foaling mammary secretion sampling slightly increases the risk of mastitis development (infection of the milk and mammary tissue or udder). This is true for any animal when milking is performed manually, especially if precautions are not taken to wipe the skin and teat surfaces clean, and dry them, prior to obtaining the sample. If you note clumps of debris, or pink to red discoloration in the milk sample obtained from your mare, this may indicate an infection and you should consult your veterinarian for proper treatment.

USE OF THE FOALWATCH™ AND SOFCHEK™ TESTS FOR EVALUATION OF PRE-FOALING MILK CALCIUM CONTENT AND THE APPROACHING READINESS FOR BIRTH IN THE MARE.

Trouble Shooting:

It is not unusual for some mares to reach 100 to 175 ppm and remain at that level for several days at a time before proceeding up the scale to 200 ppm (or above). Variations occur between mares, and even within the same mare from year to year. Patience and careful monitoring on a once to twice daily schedule are a must.

A dramatic rise, or significant change in value, over a 12 to 24 hour interval indicates that the mare is advancing towards her actual delivery. Occasionally a value will drop from the previous day's sampling, this is not a cause for alarm. Repeat your dilution technique to be certain that it was accurate, and carefully draw up small increments of the diluted sample, inverting the FoalWatch™ chamber several times between each aspiration.

Reading the scale with each repetition, and observing the color change. Initial color of the diluted sample once the indicator dye has been added to it will vary from early in the mares testing period to later when she is closer to foaling. Early samples will appear more orange in color, later samples will appear a rose-pink to reddish purple. This is a normal variation we have observed and is not a cause for concern in accuracy of the result.

Read the FoalWatch™ scale at the first color change. At the transition stage, you may first note a slight greyish discoloration, or the solution in the chamber might appear to be colorless. Continue aspirating small amounts at a time, gently inverting or mixing the chamber between each aspiration, until you see a definite blue color. Then read the scale to determine the final value.

If bubbles are present in the solution at this point, stand the vial upright for a few minutes and re-read the scale. There may be a slight alteration in the actual value once the bubbles have disappeared. Base your estimate of the actual value on the bubble-free reading, estimated to the nearest pre-marked line on the scale. If you have to guess at the value, 'fudge' to the higher ppm line to be safe.

Please contact Dr. Ley if you have any questions, concerns or comments.