As lush spring grass is low in magnesium another source of magnesium must be made available to the herd. Where milk yields justify concentrate feeding, then this is the most effective method for providing supplementary magnesium Pasture dusting with finely ground calcined magnesite . Half the rate can be used if using day and night paddocks or strip grazing. Dusting is best carried out when the grass is damp e.g. covered in dew. Cystic Cows Pregnancy diagnoses may show an increasing number of cystic cows in some herds.
Some cystic cows show very frequent and irregular heats.
This may lead to an extended calving interval which is estimated to cost between 2 and 4 per cow per day beyond the desired 365 day calving interval. Cysts occur more frequently when an animal is under stress. Incidence is highest in older cows from higher yielding herds and where the cows have experienced health problems, especially difficult calvings. Good management has been shown to be effective in reducing their incidence. Work closely with your vet.