Stray Voltage Problems in Dairy Cattle

Stray Voltage and Milking performance in Dairy farms

Stray voltage problems (also called “ground current”) in dairy cattle with currents upwards of 3.6 mA have been shown to cause cow discomfort and poor milking performance. Dairy cows act nervous and do not consume all their feed and don`t drink the normal amount of water needed to produce milk at the level they can in a given Dairy barn facility. Lower milk production, increases in incidence of mastitis/somatic cell counts and reproductive problems can arise. Preventing Stray voltage is an approach that makes way more sense.

What is the mechanism of Stray voltage?

When milking cows make contact with metallic structures of the barn or facility they are in, a current flows through their bodies as a result of them offering an electrical resistance. They can conduct the electricity but have an inherent resistance. The level of this current is determined by how well the system of housing they are in is grounded. Depending on the current that flows through the cow, there is nervous stimulation. This current becomes relevant when certain Volts are reached and this – paired with the resistance of the animal – will cause problems mentioned above.





When dairy cows are exposed to stray voltage, the reaction that results begins with Sensory nervous stimulation that goes largely unnoticed and progresses to involuntary contraction of muscles in an obvious aversive manner. The subtle blinking of the eyes, tail swishing or limb lifting and other changes in behavior may occur – such as avoiding the feeding area or water intake. So the path to feed and water must be examined very closely for the presence of Stray voltage. Stray voltage testing is necessary to find out the exact effects. The exposure has to be long and strong enough for the milking cow to search out a different path from what she is used to. Her behavior change can then be traced to an issue with stray voltage. Popular breeds of dairy cattle under modern production systems can be subject to problems related to stray voltage.


There are numerous resources that can be found. Principally, a few key points need to be kept in mind when you are on the hunt for Stray voltage:

Are any of the below factors causing a drop in milk and cheese production?

  • Poor nutrition
  • High temperatures
  • Infectious diseases
  • Milking machine defects
  • Improper handling of cows



Are you seeing a reduced water intake and WHY?

Water intake is primarily determined by four factors:


  • dry matter intake
  • milk production
  • air temperature
  • sodium intake.


Exceptions occur when cows are not able to swallow water because of some physical disability or when the cow cannot reach a water source. Over a period of several days, a cow must consume enough water either through drinking or in forages to maintain a balance in body constituents. A change in water intake can occur whenever one or more of the four major determinants of water needs are altered.


Here is a great resource: ·




Breeding for efficiency Fleckvieh x Holstein

Fleckvieh x Holstein as an example for breeding cattle


Balanced, productive and efficient dual purpose cattle suitable for the production of milk, beef and by-products, that can be kept in all production systems of the world. The principle is to use a sire of the Fleckvieh breed – original Simmental and in 1830 Fleckvieh formed its own breed with out crossings of Red Holstein and Montbiliarde cattle. These out crossings are used with small percentages in order to keep the dual purpose nature of the ideal Fleckvieh animal going. See more at

So how does a crossing program Fleckvieh x Holstein work?

The F1 (first filial) generation is when the farm`s goal is to make the following changes:

  • Improvement of substance and muscling of the dairy cows
  • Improvement of conformation
  • Improvement of fitness
  • Improvement of of the quality of the calves (fattening ability) and of cow type
  • Improvement of milk protein content
  • Reduction of mastitis and somatic cell count

In order to reach good results in the F1-generation the Fleckvieh sire has to meet the following demands:


  • Good breeding values but not too high milk values
  • Good breeding values for classification of the carcass

Selected bulls might show negative figures for frame, but no compromises should be made as far as muscling, conformation and udder are concerned. More detail can be seen wen you enter a bull`s name in the “Search” of


Future generations

The goal to breed a balanced F1 crossed animal that has a maximum amount of heterosis, brings about the predisposition for good growth and makes the first 100 days of the lactation without melting too much of the body substance, since the cow has to become pregnant again soon in order to meet the demand of one calf per year.

Advantages of the F1 generation

  • Exploitation of the heteorsis effects, that express particularly in fitness traits
  • Excellent production and low somatic cell counts
  • Longevity and excellent health
  • Good fattening abilities of the crossed calves

The mating programme for the production of the F2, F3 and F4-generation Fleckvieh x Holstein

The F1 generation cow should be judged according to the following criteria:

  • Does the crossbred cow have enough muscling?
  • Do type traits and udder meet the demands?
  • Which traits (type traits, performance) have to be improved?

In the case the F1 cows don’t show enough substance and muscling, again a bull from the F1 generation programme should be used.

In general we recommend bulls from the upper third of the population of the Fleckvieh breed to produce the F2 generation. In this step the milk production is of great importance.

Fleckvieh can be used for all crossing steps of absorption crossing.



Buying of the young sires as done by Bayern Genetik in Bavaria:

Breeding bull selection – types of cows that result

Bavarian Fleckvieh Genetics/Bayern Genetik purchases  genomically tested breeding bulls each year at local livestock auctions or directly out of the farmer`s barns. They select their bulls from a population of 750.000 Fleckvieh herdbook cows in Bavaria. These are Fleckvieh animals – originally Simmental but Fleckvieh formed it`s own breed back in 1830.

Many of these young breeding bull sires (candidates) come out of so called planned matings, which means especially selected siredams were mated to the best Fleckvieh sires available. The expected results in their progeny which becomes evident over time is listed in a ranking.

The other bulls come out of regular but promising matings with herdbook cows. They also purchase breeding sires from other countries like Austria, the Czech Republic, Australia and South Africa. This secures a large gene pool with bloodlines being maintained and a very low inbreeding coefficient. Also cow families and bloodlines are important for decision making. Bayern Genetik ( wants to offer genetics that proves its worth in the long term in all different kinds of production systems and climates.
When buying bulls, they focus on production and fitness traits. However, great importance is also attached to the type traits of a bull. Bavarian Fleckvieh Genetics/Bayern Genetik believes in dual purpose and therefore  it is crucial how a bull looks.


At the end of the day, the target is to have more proven sires to pick form that match the needs of the particular farming operation.