August and September are the times of year when dairy cows in some areas are dry or close to going dry. Now is a good time to review your overall management program, but especially for dry cows. Pregnant cows If you do not have a recent pregnancy check, have a veterinarian check the bred cows and heifers that have not been confirmed pregnant to verify that they are pregnant. Some cows will lose their calf in the summer heat.
Dry cow management
Proper management of the dry period is critical. Body condition score of a cow should be 3.5 to 3.75 on a 5-point scale. If a heifer is calving, her body condition score should be around 3.5.
All cows should be dry treated at dry-off. Follow the recommendations of your local veterinarian. A vaccination program might include BVD, IBR, PI3, BRSV, Lepto-5, Clostridia-7 and possibly a vaccination for scours or mastitis. If necessary, cows also may be injected with selenium before calving to decrease retained placentas and possibly assist with rebreeding in the next lactation.
Check your ration for selenium levels if you have more than 20 percent retained placentas in the summer. Also consider injections of 7 cc of MU-SE at dry-off and three weeks before calving. A balanced diet of forage and, if needed, grain, should be provided to all dry cows. Trace minerals should always be available to cattle.
Cows need to calve in a clean, dry environment in good body condition. Watch heifers closely in case they need assistance at calving. If a cow has problems calving or if she is not eating, you or the veterinarian may need to treat her so that she will begin eating soon and can begin producing large quantities of milk in early lactation. If assistance is provided, use a disinfectant for you, the cow and any equipment used. Watch cows closely for health problems, especially retained placentas and metritis. Calving is the best time to deworm cattle since early lactation is the time when deworming is most likely to be economical.
Most herds on pasture may need to be dewormed but check with your local vet or do fecal egg counts to determine the level of contamination with internal parasites.
Management of newborn calf
Make sure the calf is breathing and assist if needed. Devices for artificial respiration are available, but most producers can tickle the nose with straw or hay to get the calf breathing. At times, it may be necessary to hold it by its hind legs to drain fluid from the lungs to get it breathing. Dip or spray navel with 7 percent iodine. Make sure the calf gets four to six pounds of good quality colostrum as soon as possible but within six hours of birth. Vaccinate if needed, especially for scours.
Heat stress can decrease milk production by 15 and 30 percent per day as cattle eat less and also can lower reproduction performance and animal health. As the holding pen can be the most stressful location for the lactating cow, it should be given priority over other areas of the dairy for installing facilities to improve the cowsâ comfort during hot weather.
Holding pens should be shaded and cooled to make the area a desirable location for making cows comfortable during hot weather. A well-cooled holding pen should result in cows wanting to come to the holding pen when fans and sprinklers are in use. Cows that are cooled in a holding pen usually produce 1.7 to 4.0 pounds more milk per day than cows that are not cooled in the holding pen. In one study, cows that were cooled five times per day for 30 minutes in the holding pen produced five additional pounds of milk per day compared to uncooled cows. PD
â Excerpts from University of Arkansas Dairy Digest, Vol. 16, No. 4
Jodie A. Pennington, Former Extension Dairy Specialist, University of Arkansas