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A dry cow in good condition. The ribs are well covered but there are no patchy fat deposits in the brisket or flank. Dry cow programs in Oregon vary from "rough-.

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Dry Cow Feeding and Management Oregon State University Extension Service • Reprinted September 1977 • EC 925

A dry cow in good condition. The ribs are well covered but there are no patchy fat deposits in the brisket or flank.

A dry cow carrying too much condition. Notice the fat deposits in the brisket and flank areas, and the fatty thickness around the withers and rump.

Dry cow programs in Oregon vary from "roughing it" to feed lot-type fattening programs. Since research and common sense dictate that the dry period is an important and integral part of the whole dairy program, let's identify specific objectives for it. It is a necessary management practice to have cows calve approximately every 12 months to maintain an economical level of milk production. A part of this program is to cease milking the cow about 60 days before she calves. This period is referred to as the dry period in this circular. A dry period is necessary for nearly all dairy cows in order for them to produce up to their potential. Research with identical twin heifers shows a drop in milk production when cows have no dry period. Compared to cows with a 60-day dry period, second lactation experimental cows produce only 75 percent, and third lactation only 62 percent as much milk as cows with normal dry periods. This occurred when the cows were in good body condition, showing that rest is necessary for udder secretory tissue regeneration and proper hormone balance. Data from the Dairy Herd Improvement Association records show that cows produce about the same amount of milk with dry periods between 40 and 70 days in length; while cows with either

longer or shorter dry periods produce less milk per year. The usual length of a dry period is 60 days to complement a standard 305-day lactation. A dry period of 50 to 60 days is a reasonable goal. Of course, this implies that the dairy manager has sufficient records to accomplish this. Drying off procedure When the time comes to dry off a cow, it can be done quickly. This is easily done with those cows producing less than 40 pounds of milk by removing grain from the ration, and the abrupt cessation of milking. For cows producing higher amounts of milk, it is best to anticipate the dry period and remove grain from the ration, change to lower energy forage, and limit drinking water for several days. This will reduce milk production to 40 pounds per day or less, at which point one can stop milking. There is no need to milk the cow out after drying off if she has a healthy udder. In cases where mastitis is suspected, milk the cow out 2 or 3 days after turning her dry and then treat to eliminate mastitis. Mastitis treatment Cows with diseased udders should be treated at the start of the dry period. Moreover, since it has been shown that some cows can become infected with mastitis organisms during the dry

period, many veterinarians recommend treating every cow as she goes dry regardless of her udder health. Dry cow treatment is particularly effective and offers the best chance to cure mastitis. Dairy managers should work out the proper dry cow program for their herd with the help and advice of a veterinarian. The important thing is to have a program that will maintain or improve udder health in your herd. Other management practices Because most worming medicines can only be used during the dry period, and discomfort and blood loss from blood sucking lice will adversely effect milk production, this is an excellent time to treat cows for both internal and external parasites. Several sprays and dusts that will control lice are obtainable through farm supply stores. Be sure to read the label to make sure you are using the right material in the proper way. Misuse may contaminate the milk causing it to be unmarketable. Management practices for sanitary milk production, such as clipping the udder and flanks, can also be done at this time. Nutrition Dry cow feeding is a very important part of the dairy program. Both research and practical experience have demonstrated that proper feeding can greatly reduce the incidence of certain diseases such as ketosis, milk fever, and displaced abomasum. The nutritional requirements of the dry cow ration are shown in the following table:

The table shows that energy concentration for dry cow ration can be low compared to the milk producing cow. When cows are underfed, and finish their lactation in poor body condition, feeding them grain will increase their body weight and improve milk production during the following lactation period. In well managed herds today, however, most dairy cows are in good flesh when turned dry. In fact, research shows that cows gain body weight more efficiently while milking than when dry. Dairy managers can save feed and money by taking advantage of the cow's ability to store energy during the last 3 or 4 months of lactation, plus cows will be in good body flesh when turned dry. Therefore, the feeding program during the dry period needs to be one that only maintains body weight or supports very small gains. Excellent quality high energy forage, particularly com silage, should be limited or diluted with lower energy forage to prevent fattening. It has been the practice of some dairy managers, in recent years, to feed grain or com silage liberally and to over condition dry cows. This practice leads to problems, including: • Ketosis—fat cows often have poor appetites following calving, this predisposes them for ketosis. Ketosis causes rapid loss of body weight and greatly reduces milk production. Dairy managers should be advised, however, that dry cows should not be underfed so that they lose body weight as this also can cause ketosis and low milk production. Frequently observe the condition of dry cows and adjust feed ration accordingly.

Nutrient Requirements of the Cow ^=^^^^===^=^^^ Dry Matter Basis Dry cow Crude protein Total digestible nutrients Fiber Calcium Phosphorus Calcium to phosphorus ratio Magnesium Sulfur Copper Manganese Zinc Cobalt Iodine Selenium Iron Vitamin A Vitamin D

High producing cow

8.50 % min. 53.00 15.00 .40 .30

% % % %

min. min. min. min.

1.5:1 to 2.5:1 .08 % min. .20 % min. 10.0 ppm min. 20.0 ppm min. 40.0 ppm min. 0.1 ppm min. 0.6 ppm min. 0.1 ppm min. 100.0 ppm min. 1450 lU/lb. 140 lU/lb.

16.0

% min.

70.0 15.0 .60 .40

% % % %

min. min. min. min.

1.5:1 to 3:1 0.1 % min. 0.2 % min. 10.0 ppm min. 20.0 ppm min. 40.0 ppm min. 0.1 ppm min. 0.6 ppm min. 0.1 ppm min. 100.0 ppm min. 1450 lU/lb. 140IU/lb.

• Displaced Abomasum — cows fed liberal amounts of grain or com silage shortly before, or after, calving are subject to a condition where the true stomach (abomasum) migrates from the right to the left side of the rumen, causing partial blockage of the digestive tract. This condition usually occurs within 2 weeks of calving; feeding long hay in preference to cubes or pellets will help prevent it. • Fat Cow Syndrome—is characterized by a pale, fatty liver, poor appetite, and poor production. Some cows actually die from this disease. Those that do not die usually have a poor appetite, lose weight, produce less milk, and respond poorly to treatment. Recent research at the Ohio State Extension Experiment Station suggests that a high protein ration (15 percent protein) during the dry period is partially responsible for the "downer" cow syndrome.

Calcium, phosphorus, and the ratio of calcium to phosphorus is extremely important to the dry cow. Excessive amounts of calcium in the diet can predispose cows to milk fever. Because of high calcium content, legumes such as alfalfa should make up only part of the forage in a dry cow ration. Dilute legume hay or silage by 20 percent to 50 percent with non-legume hay or corn silage to reduce calcium. A favorite feed of dairy managers for dry cows is oat hay because of its narrow calcium to phosphorus ratio. Phosphorus is low in most of the forages produced in the United States and it should be either added to the grain ration or fed free choice. Adding phosphorus to the grain is a more positive way to insure adequate intake. Low phosphorus intake is associated with milk fever, downer cow syndrome, retained placenta, and anestrus (no heat) following calving. Since little or no grain is fed to dry cows, a mineral mix high in phosphorus should be fed free choice. Feeding experiments have indicated excellent milk fever prevention when the calcium to phosphorus ratio is 1:2. However, it is often difficult and/or expensive to achieve this. Milk fever control has been good when the phosphorus level is at or above the nutrient requirement and the calcium to phosphorus ratio does not exceed2:1. (Seetable.) Salt should be limited to dry cows as excessive salt intake is associated with udder edema (caked udder). Salt should not be mixed with other minerals during the dry period as this may encourage excessive salt intake. Trace minerals are also needed for health and reproduction. Those trace minerals especially associated with reproduction are: Iodine—deficiency causes goiter in calves; manganese—crooked calf syndrome; and selenium—retained placenta and white muscle disease in calves.

tocopherol acetate (commercial preparation) may reduce the number of retained placentas. This same commercial preparation will prevent white muscle disease in the new bom calf. Lead or challenge feeding Lead or challenge feeding has been widely and successfully adopted. The program gets dry cows started on the lactation ration about 2 weeks before calving. This allows micro-organisms in the rumen to adjust to the milking ration and challenges the cow to produce to her maximum ability. However, grain should be limited to 1 percent of body weight before calving to help prevent displaced abomasum. The program has increased milk production per cow and has proved economically successful. Grouping those cows to be lead or challenge fed is a problem in small and medium sized herds because of the small number at any one time. One suggestion is that they be included with the lower producing cows when cows are grouped according to production. The grain requirement for low producers and dry cows 2 weeks before calving should be similar. Statistics show that cows suffer most from injuries or diseases during the period from 6 weeks before to 6 weeks after calving. Proper care and feeding of the dry cow will decrease the incidence of disease and injury and enhance the profitability of the cow. Prepared by H. P. Adams, Extension dairy specialist, Oregon State University.

Dairy cows require fat soluble vitamins A, D, and E. A deficiency of vitamin A is associated with poor maintenance of the membrane linings of the body, thus exposing animals to disease. Vitamin D, with adequate calcium and phosphorus insures proper bone growth and prevents rickets in the calf. Thirty million units of vitamin D for 5 to 7 days before calving have been used to prevent milk fever. Intramuscular injections 20 days before calving of 50 mg of sodium selenite and 680 IU of alpha

A cow that has calved and is in condition to produce a large quantity of milk efficiently.

OREGON STATE UNIVERSITY

EXTENSION n SERVICE

OREGON STATE UNIVERSITY

EXTENSION n SERVICE

Extansion Sarvica, Oragon Stata Univarsity, Corvallla, Hanry A. Wadsworth, duced and dlatributad In furtherance ol tha Ada of Congraaa of May S and cooparativa program of Oragon Stala Univarsity, tha U. S. Dapartmant ol Extension invties participation In Its program* and otters tham aqually to

director. Thla publication wat proJuna 30, 1914. Extension work ia a Agriculture, and Oragon counties. all paopla, without discrimination.