Nutrition is the basis of any successful livestock management operation. Management includes virtually everything associated with the enterprise and includes such things as marketing, herd health, sire selection, pasture management, nutrition, etc. All aspects of management are important and all must be considered together. Problems develop when the individual components of the management program are singled out or not considered at all. When livestock are pregnant, stressed from cold, or fed improperly, the result can be depressed reproductivity, increased mortality, suppressed productivity and stunted body size. Animals need some source of supplemental feed, especially during the last few weeks before parturition, in order to avoid these effects.
One of the key components associated with herd management is its nutritional status. The animal system nutrients are utilized in a very definite order of priority. Specifically, consumed nutrients are used first to maintain the animal, ie. blood circulation, breathing, temperature. Next, dietary nutrients remaining in the goat go to meet the demands of fetal growth and milk production. Remaining nutrients are then used for body growth with reproductive cycling the last priority of nutrient use. In areas where inclement (cold) weather occurs, the added stress of keeping warm becomes part of the maintenance requirement.
Planning the Feeding Program – To effectively plan a feeding program we must know three basic things;
Herds of goats generally consist of animals of various ages, weights and production status, and each class of goat will have a different nutritional requirement. Thus, the number of kids, yearlings, bred and/or lactating does, males, etc. will need to be known in order to develop a sound nutritional program. Secondly we will need to know how long the feeding program will be. For example, is it just a wintering program that will run from December 15 to May 15, or is it an emergency feeding program during the last trimester of pregnancy? Lastly, we will need to know what feed resources we have available to use in the feeding program and what their relative quality is. Ideally, available forages and pastures will be used. If feeds are purchased, we will need to optimize costs while maximizing the nutrients.
Implementing the Feeding Program – Most of the information we have on goat nutrition comes from dairy and Angora goats. Goats are browsers and as such have the ability to select higher quality diets than other free-ranging herbivores grazing the same pasture areas. Daily nutrient intake of goats is a direct function of their dry matter intake. Meat-type goats will consume 3 to 3.5 percent of their bodyweight, while lactating does will consume 4 to 5 percent of their body weight in dry matter feed daily. Table 1 presents suggested daily nutrient requirements for various classes of cashmere goats.
The data in Table 1 illustrate that goats with the highest nutrient requirements are lactating does, pregnant does and growing kids. Goats on summer pasture frequently meet or exceed these requirements. However, as pastures cure and mature in the late summer and fall, nutrient content of the grazable forage frequently drops to 6 to 10 percent crude protein, and by spring it may be as low as 2 to 3 percent crude protein. The other nutrients of energy, vitamins and minerals decrease in a comparable manner. Thus the need for supplementation or a planned feeding program. Table 2 presents the nutrient content of Wyoming hays produced under various management schemes and harvested at different stages of maturity. Data on Wyoming hay is used as its climate and conditions closely approximate those of many goat growing regions. Check with your local Extension Agent or the Soil Conservation Service to obtain data for your area.
When we compare the protein content of the Wyoming hays (Table 2) to the requirement of the various classes of goats (Table 1), we see the grass hays do not meet the protein requirement of any goats represented. The immature grass hays (heads emerging) did meet the energy (TDN – total digestible nutrients) needs of dry does. The alfalfa hays met or exceeded the minimum protein requirement for all classes of goats, however fell short in several cases of meeting their energy (TDN) needs. This points out the need for supplementation and the value of knowing the nutrient composition of the feed resource used.
Table 3 presents the nutrient composition of feeds commonly available. These, when combined with native forages or harvested hays, can provide rations that will meet the nutritional requirements for all classes of cashmere goats discussed in Table 2.
Table 4, Section A details the nutritional requirements to maintain bodyweight. Section B defines how much more energy and total digestible nutrients are required for body growth. The next sections define how much more energy and TDN are required for gestation, lactation and fiber production. These requirements are directly additive, depending upon the time of year ie: goats grow or lactate in the summertime, while they grow fiber in the fall and gestate only in the winter. Thus, their nutritional requirements will change with the seasons.
Example: A doe 40 kg doe is expected to maintain her bodyweight, grow 200 grams of cashmere as well as gestate a fetus. She needs 448 grams of TDN to maintain her weight, 397 grams of TDN to gestate and 160 grams of TDN to grow fiber. This adds up to 1005 grams of TDN daily and this can be obtained by eating 2 kilos of irrigated grass hay (at 54% TDN). However, this amount of grass hay only supplies 160 grams of the necessary protein requirement of 235 grams protein (63 grams plus 82 grams plus 90 grams). Clearly, she needs to have some supplemental protein.
The nutritional management of a goat herd is a very complex and often difficult task. However, with careful, thoughtful planning one can develop an effective nutritional program that not only meets the requirements of the goats, but also enhances other management aspects of the enterprise, ie. breeding, kidding percent, etc., resulting in a more profitable enterprise.
Copyright 1994 Capricorn Press. Not to be reproduced without express written consent of Capricorn Press.