Key Technical Points for Feeding and Management of Dairy Cows During the Dry Period

In order to raise dairy cows well during the dry period, the dry period is generally divided into two stages for feeding: the early dry period and the late dry period. The entire stage from the start of drying off to 15 days before calving is called the early dry period, and the 2 weeks before calving to parturition is often called the late dry period (also known as the prepartum transition period).

In the early dry period, dairy cows are generally given a moderate nutritional status, using 4~5 kg of high-quality hay and about 10 kg of mixed concentrate. The body condition score is 3.8~4.2, with a plump body and glossy coat. For thin dry cows, nutrition should be increased; on the basis of the nutritional requirements for pregnancy, an additional 5~10 kg of the nutritional requirements for milk production should be added, so that the cow's body condition recovers to between 3.5~4.0 within 20 days. Within one week of drying off, the udder condition should be observed; if there are hard lumps and the cow is restless, treatment must be given promptly, and drying off should proceed only after the condition improves. During this stage, the diet should be based mainly on roughage, with appropriate matching of concentrate. The amount of concentrate generally accounts for 0.6%~0.9% of body weight, that is, 3.5~5 kg, and the dry matter ratio of concentrate to roughage is between 30:70~20:80. The crude fiber content of the diet should not be lower than 18%. For first-calf heifers, the feed allowance should be increased by 10%~18% to prevent an excessively thin body condition and negative metabolic balance after calving. The diet of dry cows must be formulated from high-quality, easily digestible feeds. Spoiled and deteriorated feeds must not be used. The use of low-nutrient-concentration roughage and succulent feeds should be limited to avoid pressing the fetus and causing premature birth. In addition, clean drinking water should be provided. In summer, the water temperature is best controlled at around 100C, and in winter at around 150C. Drinking ice water must be strictly avoided.

In the late dry period, cows should be given a medium-to-upper nutritional level so that the cow's body condition at calving is close to a score of 4.5. Therefore, based on the cow's body condition, appetite, manure type and expected milk yield at the time, the amount of concentrate fed should be increased. Generally, the concentrate is increased to 1~1.5 kg per 100 kg of body weight, but the concentrate-to-roughage ratio of the diet must be kept between 30:70~40:60, and the crude fiber level must not be lower than 17%. Of course, the increase in concentrate level should follow a gradual schedule, generally increasing by 0.3 kg per day. When cows show anorexia, concentrate should no longer be increased; only after this phenomenon disappears can a slight further increase in concentrate be considered. For cows with excessive udder expansion or severe edema a few days before calving, concentrate should be appropriately reduced, succulent feeds should be stopped, and salt usage should be reduced. If wet concentrate is used for feeding, the concentrate at this stage should not be mixed too wet. From 20~30 days before calving, a low-calcium diet should be fed, reducing the calcium content in the dry matter of the diet to 0.2%, and salt usage should be reduced. During the 2~3 days before calving, anionic salt feed may be fed to prevent milk fever in dairy cows. At the same time, to prevent constipation, the amount of laxative feeds such as wheat bran in the concentrate should be appropriately increased, and may account for 15%~23% of the concentrate. In the late dry period, the udder condition must be carefully checked; if there is mastitis, treatment should be given immediately.

In addition, throughout the entire dry period, cows should be allowed free exercise to reduce dystocia, and crowding must also be prevented. Strengthen pregnancy maintenance: do not feed deteriorated feed, do not provide ice water, do not wash cows with cold water, and do not let cows fall or slip.