Tail painting: an economical and effective heat detection system

A major factor limiting optimum reproductive performance on many farms today is the failure to detect estrus in a timely and accurate manner. Increases in herd size and milk yield have been implicated as contributors to the decreased reproductive efficiency experienced today.

For example, during the past ten years the average Virginia DHI dairy herd has experienced a 35% increase in milking cows and a 20% increase in milk yield per cow without the same increase in additional labor force. During this same time period the average calving interval has increased from 13 to 14.5 months. This decrease in reproductive efficiency conservatively cost $12,000 per year per herd if one assumes a $2 loss per each day open over 115 days and an average herd size of 135 cows. This is not even taking into consideration the additional losses of fewer replacements, increased labor, fewer cull cows, and increased drug and veterinary expenditures.

Our research, with the electronic heat detection system HeatWatch, has reported that the "average" Holstein cow is mounted 7 times during the 7 hours of "standing" heat. During the summer months mounting activity decreases to 5 standing events and high producing cows express shorter and less intense standing activity than lower producers.

Why Tail Paint?

   * Correct use of tail painting identifies almost 90% of cows in standing heat.

   * Tail painting picks up cows which are only standing for a short time that would otherwise be missed.

How to Tail Paint

   * Use commercially available specifically formulated products (house paint may not rub off correctly, water-based paints won't last). Contact your A.I. representative, all sell an acceptable product for tail painting.

   * Apply paint to cover those points near the head of the tail which will be rubbed off by the brisket of the riding cow.

   * A strip about 2 inches wide and 6 inches long painted along the ridge of the backbone immediately above the tail is recommended.

   * Remove loose hair and dirt before applying tail paint. Do not apply paint too thickly.

   * Check the paint strip at each milking or during lock-up if head locks are available. In 90% of cases, most of the paint will be rubbed off when a cow has been in standing heat. A further 5% of cows will lose some paint, and with the remaining 5% confusion can occur so experience in reading tail paint is needed for these cows.   Paint is rarely removed by occasional mounting of cows not in standing heat.

   * Cows detected on heat and then inseminated should not be repainted until the following milking. Use a different color when re-painting inseminated cows. Unmated cows are then easier to identify.

   * Tail paint should last four weeks unless the coat hair becomes loose with shedding. Touch ups with brush or aerosol tail paint are required if this happens.

When to use Tail Paint

   * Three weeks before the voluntary waiting period (50 days in milk if start breeding at 70 days), tail paint can be used to identify non-cycling cows early.

   * At the voluntary waiting period every cow in the breeding herd should be painted.

   * May want to use one color for cows prior to voluntary waiting period, one color for cows after the voluntary waiting period and before first service, and one color for cows that have been inseminated.

By Ray L. Nebel, Extension Dairy Scientist, Reproductive Management
Dairy Pipeline Newsletter - Virginia Tech Cooperative Extension