The lactating doe has very high nutrient requirements. Calculate the requirements for a 4-year-old, 110-pound Boer cross doe nursing twins in week four of lactation. When lactating is selected under question #2 on the Langston Interactive Nutrient Calculator (LINC), a form drops down. Select litter size (twins), week of lactation (4), and age at kidding (4). The program then predicts production of 4.5 pounds of milk per day with 3.6 percent fat and 3.3 percent crude protein. Nutrient requirements are 2.8 pounds of total digestible nutrients (TDN), 0.41 pounds of crude protein (CP), 7.61 grams of calcium, and 5.33 grams of phosphorus, with 4.14 pounds of dry matter intake predicted (based on default dietary TDN and CP concentrations). During lactation, the doe can consume nearly enough nutrients if an abundant supply of high quality pasture is available, such as in spring or early summer. However, does will likely lose some body weight due to the high demands of peak lactation in weeks three to eight of lactation and an inability to consume an adequate quantity of feed. Kidding should take place when there is an adequate supply of high quality pasture. If there is not adequate pasture, supplemental feed will be required. Inadequate nutrition will decrease body condition, reduce milk production, reduce kid weaning weight and increase kid mortality.
If feeding bermudagrass hay and a 16 percent dairy ration, 2.6 pounds of hay and 2.0 pounds of the ration are required to fulfill requirements. However, the doe will still lose 2.0 pounds of body weight per month. When fed high levels of grain such as the amount in this example, the animal should go through an adjustment period of two to three weeks during which time the grain portion of the diet is gradually increased to prevent digestion and other problems from occurring. Feeding a dairy ration and hay to a doe during late gestation and the lactating period will cost approximately $30 per animal. Utilizing available pasture as a feed source is a much cheaper alternative.
Kids are usually weaned at about 12 weeks of age. Milk production of the doe begins to decrease after the sixth week of lactation and is quite low by the 12th week. Nutrient requirements decline as stage of lactation advances, enabling the doe to maintain body condition or even increase it on pasture alone. Kids may be creep fed while nursing to increase growth rate and reduce nutrient demands on the doe for milk production.
Reference: Hart, S. 2008. Meat Goat Nutrition. Pages 58-83 in Proc. 23rd Ann. Goat Field Day, Langston University, Langston, OK.