Wintering - Cows and Bulls

Management objective: To maintain the breeding herd in good productive condition, as economically as possible.

Points to Remember

• Both critical and non-critical feed periods must be considered when planning the winter feeding program.
• The non-critical feed period for the cow is the second trimester of pregnancy. The least damage to the cow and fetus will be incurred by reducing feed supplies or feeding lower quality feeds in this period. Severe feed restriction can, however, lead to a weakened fetus and lower calf survival.
• Bulls should be sorted three ways before winter. The largest group should be the mature bulls in good condition and do not require special care. The second group is bulls which are still growing and need higher quality feed. This group includes yearling bulls which were used in the breeding pastures. The last group is the older, crippled bulls that have completed their productive life and are to be marketed.
• The normal herd health program should include both bulls and cows. Bulls are more vulnerable to lice than cows and should be treated for both warbles and lice in the fall as well as being protected from the biting flys and mosquitoes in the summer. If a fecal examination shows internal parasites, a systemic endectocide should be used.
• Salt and mineral supplements should be available at all times. They should be carefully designed to give proper supplementation of the nutrients needed according to the winter diets being fed. A hay based diet will require a different mineral balance in the supplement than will a cereal silage, green feed or straw based diet.
• A routine feed analysis of the feed supply for the winter should be taken early to ensure that all the necessary energy, proteins, minerals and vitamins will be supplied to the herd.

• Thin cows and replacement heifers should receive extra feed and higher quality feeds in the third trimester of pregnancy.
• Heifers which have just weaned their first calf may also need extra feed if they have lost condition over summer.
• Condition scoring of all females will allow for more precise planning of the amount and quality of feeds that will be needed during the winter feeding period.
• Bulls should also be included in the planning for health and parasite control programs as well as for the winter feed requirements.

• Plan for third trimester feeding. Remember that the best quality feed should be saved for the third trimester (last ninety days) of pregnancy and the period from calving until there is good new grass for grazing.
• Seeking new management ideas and long-term planning are activities for the mid-winter period.
• Analyze production records from the past year, compare with previous year's records and assess progress and needs.
• Plan breeding programs and plan the purchase of new bulls.

Other Documents in the Series