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FEEDING THE PREGNANT AND MILKING DOE

T. Sahlu and A. L. Goetsch

E (Kika) de la Garza Institute for Goat Research

Langston University

Langston, Oklahoma 73050

Introduction

Feeding the high-producing dairy goat is an ever increasing challenge. As animals are selected for increased milk production, greater attention to diet composition, feed quality, and the physical form of feedstuffs is required. In addition, feeding strategies must provide for more nutrient dense diets yet remain cost effective.

Whether you are a farmer with 300 goats or a caprine enthusiast with three pets, the nutrition of your animals is of considerable importance. Not only can over- or under-feeding of animals lead to metabolic disorders, general poor health, and low production, it also can cause huge financial losses - something very few of us can afford.

How then can we ensure that we are feeding our animals at optimal levels? The answer is simple: through knowledge. We must know the animal's nutrient requirements, physiological changes that a doe goes through when pregnant or lactating and how these affect her requirements, and the quality and nutrient content of the feeds available. Formulating a diet that will be consumed to meet the nutrient needs of the animal then becomes a fairly simple task.

This workshop was designed to discuss and give better insight into:

the physiological changes in animals associated with pregnancy, kidding, and milking;

how these stages interact and influence one another; and

how to formulate feeds to best meet the animal's requirements that will ultimately optimize financial returns.

Doe Production States

Goat milk, meat, and fiber producers should be aware that pregnancy and lactation are interrelated. How you treat and feed your animals during pregnancy influences milk yield, milk quality, lactation duration and, subsequently, kid vitality and growth rate. Fiber production can also be impacted.

Early and Middle Segments of Pregnancy

Energy intake is one of the most limiting factors for milk production. Like the dairy cow, the lactating goat is able to draw upon body reserves in early lactation to meet energy requirements when feed intake lags behind nutrient demand. In early lactation, energy derived from body reserves is utilized more efficiently than feed energy for milk production. These body stores can be replaced during mid- and late lactation and in the dry period. The rate and extent to which a dairy goat is capable of drawing upon body reserves to meet the energy requirement in early lactation is critical in determining her ability to produce and sustain a high level of milk production. In addition, the ability to replenish body stores has a direct impact on the ability to conceive later.

It has not been clearly established when replenishment of body stores is most efficient or what is the optimal time pattern of tissue replenishment during late lactation and the dry period. This most likely varies with conditions such as the quantity of tissue lost earlier. From a strictly energetic point of view at particular points in time, the efficiency of energy use in tissue replacement is greater in late lactation than in the dry period, suggesting that most body weight and condition restoration should be in late lactation. However, if energy required for tissue maintenance is independent of or at least not closely associated with body composition, then the efficiency of energy use might be greater for replenishment during the dry period. Dry period tissue gain rather than in late lactation would result in a minimal period of time during which tissue must be maintained before freshening. Furthermore, in the period immediately preceding parturition and lactation, to achieve highest lactation performance it is imperative to prepare the doe for lactation demands, such as increased energy intake to increase ruminal papillae development, which lends itself well to dry period tissue replenishment.

The ability of the doe to replace energy stores in late lactation or in the dry period is obviously affected by dietary energy density. Body tissue replacement increases with increasing dietary concentration of digestible energy or concentrate level, but at excessively high energy densities fattening may result from a shift in nutrient partitioning, reducing reproductive performance and increasing periparturient health problems (i.e., fatty liver). The present nutrient requirements provided by the National Research Council do not adequately address dietary energy density in late lactation or in the dry period. There is need for information on the optimal digestible energy density in late lactation and in the dry period, so that body stores are replenished most efficiently, to avoid overconditioning, and to maximally prepare does for the onset of lactation. Overall, current information available indicates that most body energy stores used in early lactation should be replaced in the late-lactation period. European recommendations are that starting in the fourth month of lactation, multiparous and primiparous goats (i.e., does and doelings, respectively) should gain live weight at approximately 2.6 and 4.9 pounds per month, respectively. Future research at the E (Kika) de la Garza Institute for Goat Research will investigate whether there are economic advantages of differences in the time when tissue lost in early lactation is replaced.

Transition or Late Dry Period

In the pregnant doe, the duration of pregnancy can be divided into three stages (day 0 to 50; 50 to 100; and > 100). Up to day 100, fetuses develop but little growth takes place. During this time, the doe requires very little additional nutrients above those which she needs for lactation, maintaining body weight, different levels of activity, and(or) her own growth (i.e., young doelings). Figure 1 illustrates the dramtic increase in nutrient requirements a doe experiences in the last 50 days of pregnancy. In the last trimester, most fetal and mammary gland growth takes place, elevating the nutrient requirements of the doe considerably. Especially with twins, triplets, and quadruplets, the space that fetuses occupy in the abdomen of the doe increases, and consequently decreases the space available for feed. During this time, the doe must be fed diets with a high concentration of digestible energy. Failing to increase the energy intake of the animal may lead to metabolic disorders such as pregnancy toxemia (also known as pregnancy disease or ketosis).

Ketosis is a common metabolic problem in early lactation and particularly late gestation with multiple fetuses. Ketosis results from an inadequate supply of glucose to maintain a normal blood glucose level. The requirement for glucose and glucose precursors is high in late gestation primarily for support of fetal development demands and in early lactation to allow the metabolism of fatty acids being mobilized from adipose tissues in support of milk synthesis. As noted later, in the last 3 to 4 weeks of gestation the dietary grain level should be increased to increase the glucose supply for fetal growth and prepare the animal to consume a mixed grain-forage diet in lactation and for the relatively sudden and large increase in demand for glucose at kidding. However, never abruptly shift animals from a high forage to a high grain diet just because nutrient requirements have increased. A drastic change can result in reduced or fluctuating feed intake, low milk fat test, large decreases in body condition in early lactation, reduced milk flow peak, poor lactation persistency, abnormal manure, and an increased incidence of metabolic diseases.

Based on research conducted at the E (Kika) de la Garza Institute for Goat Research, for the pregnant doe during the last 2 months of gestation it is recommended that daily allowances of crude protein (CP) should be at least 10 or 11% (as fed basis) and should meet or be no more than 10 to 20% above the energy recommendation of the National Research Council. Although there appears to be little influence of diet on kidding traits, care must be taken in feeding the late-pregnant doe to avoid complications arising from metabolic disturbances. Goats should have adequate fat stores at kidding to achieve high milk yields in early lactation. But, over-feeding concentrates does not enhance milk production and can be detrimental. For example, high forage intake in late gestation promotes high forage intake in lactation.

During the 3 to 4 weeks preceding kidding, does should be acclimated to any new feedstuffs to be used in lactation. The dietary grain level should be increased slowly if only forage was being consumed previously, so that at least 1% body weight of grain (dry matter basis) is being consumed before kidding. However, this level should be varied with age and milk production potential of the goat. Relatedly and ideally, forage quality should be high. Although as mentioned later, feeding of legumes, which are high in Ca, should be minimized or avoided. This increased energy density in the diet will stimulate development of ruminal papillae, necessary for high feed intake and nutrient absorption during lactation. The increased level of grain feeding also limits fat mobilization and associated metabolic problems, which is of special importance because of a decrease in feed intake that occurs in the last 2 to 3 days preceding parturition. In addition, problems with mastitis can be minimized by the increases in dietary grain level and digestible energy concentration in this transition period, due to nutrition (e.g., amino acid and trace mineral and vitamin statuses) x immunity interactions. In this regard, requirements for trace minerals in the latter part of the dry period are thought to be elevated in dairy cows, and this may be the case for dairy goats as well.

Nutrition in the transition period affects the incidence of milk fever in early lactation, although this condition is less common in dairy goats than dairy cows. In order for mobilization of adequate bone calcium (Ca) to support milk production in early lactation and maintain adequate blood Ca levels, parathyroid hormone must be produced and active. To achieve this, dietary Ca levels should not be high in late gestation; therefore, feeding legumes that are high in calcium should be minimized or avoided if possible. In addition, feeding high dietary ratios of acidogenic (e.g., NH4Cl and MgSO4) to alkalogenic minerals (NaHCO3, KHCO3, and MgO) will help maintain proper blood pH in this period so that parathyroid hormone activity in dairy cows is high, and this is expected to apply to dairy goats also. High dietary potassium levels should be avoided in this period as well.

Although iodine and calcium deficiencies have been observed to cause fetal deaths, a vitamin A deficiency is most likely to cause fetal deaths. Especially during or after a dry summer when grass and hay usually lack adequate amounts of vitamin A, specific care is required to meet the animal's requirements. A phosphorus (P) deficiency is more likely than a Ca deficiency in grazing goats because of the relatively low phosphorus concentration in forages. It is important to be aware of possible soil mineral deficiencies in the area where your animals are grazing or where your hay is produced, since this will influence the specific content of that nutrient in the forage.

Early Lactation

Figure 2 illustrates relationships between feed intake, body weight, and milk production in the lactating does. Generally, milk yield peaks 6 to 9 weeks after kidding, with the peak being about 1 week later in Alpine doelings than does. However, feed intake does not peak until the third month of lactation or sometimes 12 to 16 weeks postpartum; thus, does are usually in a state of negative energy balance during this time. Therefore, body reserves (fat and protein) have to be used to make up for this energy deficit. The animal's nutrient intake will not meet her demands until milk production has decreased to 60 to 80% of the peak. During the first month of lactation goats may lose over 2 pounds of adipose or fat tissue each week to support milk production. An average weekly loss of adipose tissue in the second month is about 1 pound.

To increase doe productivity and to ensure high feed efficiency, producers need to pay close attention to the lactation curves of does within their herds. This could help to reduce feed costs and permit more accurate monitoring of herd health. For instance, changing of does to feeding programs with lower nutrient densities should be on the basis of milk yield and body condition. Table 1 is a summary of the nutrient requirements of does at different levels of milk production. Since high-producing does direct more nutrients to milk, it is important to monitor their body condition closely to ensure that body reserves are replenished during late lactation or the dry period.

Even though daily feed intake increases after kidding, diets need to be sufficiently high in digestible nutrients to support the increasing milk yield. Based on the quantity of dry matter a doe can consume, the diet should be formulated in such a way that it meets her requirements. The doe should preferably be fed a completely mixed diet. Lactation diets should contain 60 to 75% total digestible nutrients (TDN) and 12 to 17% CP depending on the stage of lactation, level of production, and size of doe. However, responses to different dietary CP levels have varied greatly among experiments. But it is agreed upon that milk production responses to high dietary CP levels are more likely with sources of protein that are not thoroughly degraded in the rumen (e.g., fish, blood, feather, and corn gluten meals) compared with ones that are extensively degraded by ruminal microbes (e.g., soybean meal and direct-solvent-processed cottonseed meal). Furthermore, for most efficient utilization of diets high in CP, with much of the CP supplied by feedstuffs with protein that is extensively degraded in the rumen, the digestible energy concentration of the diet must be high, such as with a 60% concentrate level and high-quality forage.

Digestible energy and protein levels of diets are commonly increased by incorporating more grain and less forage. An increased TDN or digestible energy concentration in the diet can, however, lower the dietary fiber concentration below that required (e.g., crude fiber as presented in Table 1). For lactating dairy cows, minimum recommended dietary levels of neutral detergent fiber are 25 and 28% for cows of differing milk production potentials or in different stages of lactation, with at least 75% of this neutral detergent fiber from forages rather than concentrate or byproduct feedstuffs; minimum recommended levels of acid detergent fiber are 19 and 21%. From research conducted at the E (Kika) de la Garza Institute for Goat Research, it would appear that these fiber levels also can be applied to goats. We noted that lactating dairy goats producing over 7.7 lb/day of milk utilized dietary energy most efficiently and maintained a milk fat percentage above 3 when dietary dry matter was 18 to 22% acid detergent fiber. Lower dietary fiber levels can depress milk fat percentage and increase fat storage in the body of the doe or doeling, at a time when nutrient partitioning to milk synthesis is desired. Therefore, it is important to observe the ratio of concentrate (i.e., grains, which are thoroughly and rapidly digested) to roughage (i.e., forages, which are less completed and more slowly digested) and not to exceed 60:40.

In addition to feeding more grain to increase the TDN concentration, or as an alternative, fat products may be added to the diet. There are at least three advantages to adding fat to the diet: 1) it may increase total energy intake and milk production in early lactation; 2) it may allow the dietary level of grain to be decreased, allowing more forage to be included in the diet without lowering energy density; and 3) it may improve the metabolic efficiency of lactation. However, unprotected fat sources should not be included in the diet at more than 3 or 4%, since they can reduce fiber digestibility. High dietary fat levels also decrease Ca absorption. In accordance, somewhat higher levels of fat products that are inert in the rumen can be used, and many dairy cow producers include both types of fat sources in diets. In a recent experiment at the E (Kika) de la Garza Institute for Goat Research, a partially hydrogenated tallow product could be added to a lactating goat diet at up to 9% of dry matter without adverse effects. Economics should be a primary consideration, however, when making such dietary management decisions.

High-producing does in early lactation may require more protein than be synthesized by ruminal microbes from nonprotein nitrogen and protein sources that are thoroughly degraded in the rumen. However, there appears relatively less potential to temporarily meet this nutrient demand through tissue mobilization compared with use of body stores to provide energy needed for maximal milk production. Thus, feed sources high in protein that pass from the rumen without being degraded by ruminal microorganisms are frequently used in early lactation diets of high-producing dairy cows. Providing more amino acids to the small intestine will increase the supply of amino acids to the mammary gland, and as a result can stimulate milk synthesis. The potential for such a response is due to several factors: 1) an increase in the amino acids that are limiting production; 2) providing more glucogenic amino acids, thus sparing glucose for lactose synthesis or to provide energy to the mammary gland; and 3) alteration of hormone levels that control milk synthesis. The efficacy of dietary inclusion of feedstuffs high in ruminally undegradable protein in lactating doe diets has not been adequately established. Thus, there is currently an experiment to address this issue underway at the E (Kika) de la Garza Institute for Goat Research.

Some producers allow access of high-producing dairy goats to a block of trace mineral salt to ensure adequate trace mineral nutrition. Completely mixed diets should contain appropriate amounts of calcium and phosphorus, typically with a ratio of 1.5:1 (Ca:P). A level of 0.4% P in the total diet is recommended. Because the sodium content of many feeds is inadequate to meet the need of dairy goats, the diet should contain added salt, with a level of 0.5% common.

Feed Formulation and Guideline Tips

When formulating diets there are several guidelines and generalizations worth keeping in mind:

High-producing lactating animals should be fed totally mixed concentrate-forage diets, since consumption of forage alone does not facilitate sufficient energy and nutrient intakes for maximal production. The diet should be as high in digestible nutrients as possible.

For does, other than the high milk-producing ones, the most economically rewarding strategy is usually to formulate the diet based on the quality of available forage. In short, if you have got grass or hay, use it and add a supplement to it.

Grouping the animals (by stage of pregnancy, milk production levels, or period of lactation) will make diet formulation and the proper allocation of quantities and qualities of available feedstuffs a lot easier.

The maximum predicted dry matter intake of an animal is important. It influences the amount (and therefore the cost) of feed offered per animal and desired nutrient and energy concentrations. There is considerable variation among does in dry matter intake, which can vary between 3 and 8% body weight.

By adhering to the following management criteria, feeding animals at optimum levels to maintain high production efficiency becomes a fairly simple task:

1. Define groups of does (i.e., according to body weight, milk production, or days in milk) and determine their nutrient requirements (energy, protein, Ca, and P) per day. You can either work with the group combined (total requirements) or with an average doe and later multiply by the number of animals to determine the requirement of the group.

2. Estimate the dry matter intake per animal or that of the group as a whole.

3. You can now calculate what the specific level of a nutrient must be per kilogram dry matter of the diet:

3.1. Calculate the energy concentration in the diet (include fat/protected fat sources to boost the energy for early lactation, if needed and if economical).

3.2. Check dietary protein levels.

3.3. Determine dietary protein levels.

3.4. Determine the forage to concentrate ratio in the diet.

3.5. Balance the diet for minerals and vitamins.

4. Provide adequate amounts of clean water that is cool in summer and luke warm in winter. Check for feces that is too dry or too moist.

5. Keep the same feeding frequency and sequence.

6. Milk producers: check milk volume for individuals and for the group and check the amount of milk fat.

Information on the nutrient requirements of goats is available in a book called the Nutrient Requirements of Goats, published by the National Research Council in Washington, DC in 1981. It is commonly referred to as the NRC (1981). Two tables from the NRC (1981) are presented on the next two pages. The first table represents the nutrient requirements of goats while the second presents information on the nutrient content of a variety of feedstuffs. Examples of feeds formulated by using these tables are also presented. In addition to these tables, a list of relevant publications is provided, many of which are concerned with research conducted at the E (Kika) de la Garza Institute for Goat Research.

TABLE 1. Feeding the milking doe based on the level of milk productiona.

_________________________________________________________________________________

Milk TDN Protein Ca P Crude fiber

_________________________________________________________________________________

------------------------------------%-------------------------------------

> 9 lb/d 75 18 0.7 0.5 20

7-9 lb/d 71 16 0.6 0.4 23

4-7 lb/d 67 14 0.6 0.4 26

< 4 lb/d 65 14 0.5 0.3 29

_________________________________________________________________________________

aKeep in mind that these are percentages and not absolute quantities. At a specific level of milk production, the size of the doe and the amount that she can consume (% of body weight) will influence the absolute quantity an animal needs.

TABLE 2. Nutrient requirements of animals under different production stages (NRC, 1981).

______________________________________________________________________________

Body weight TDN CP Ca P

Function (lb) (kg) (g) (g) (g) (g)

_________________________________________________________________________________

ALL GOATS (Choose 1)

Maintenance only (Penned) 22 10 159 22 1 0.7

(Little to no grazing/activity) 44 20 267 38 1 0.7

66 30 362 51 2 1.4

88 40 448 63 2 1.4

110 50 530 75 3 2.1

132 60 608 86 3 2.1

154 70 682 96 4 2.8

176 80 754 106 4 2.8

Maintenance only (pasture) 22 10 199 27 1 0.7

(Some/low physical activity) 44 40 334 46 2 1.4

66 30 452 62 2 1.4

88 40 560 77 3 2.1

110 50 662 91 4 2.8

132 60 760 105 4 2.8

154 70 852 118 5 3.5

176 80 942 130 5 3.5

ADDITIONAL REQUIREMENTS

Growing:

0.11 lb/day 100 14 1 0.7

0.22 lb/day 200 28 1 0.7

0.33 lb/day 300 42 2 1.4

Late pregnancy 397 82 2 1.4

Lactation (per lb of milk):

if 3.0% milk fat 153 29 0.9 0.6

if 4.0% milk fat 157 33 0.9 0.6

Mohair production

(At different annual fleece yields)

4.4 (lb/year) 16 9

8.8 (lb/year) 34 17

13.2 (lb/year) 50 26

17.6 (lb/year) 66 34

_________________________________________________________________________________

CONVERSION FACTORS: 1 kg = 2.2 lb = 1,000 g; 1 lb = 454 g.

TABLE 3. Estimated as fed nutrient composition (per lb) of feeds (NRC, 1981).

______________________________________________________________________________

Feedstuff Moisture TDN Protein Ca P

Common name Scientific name (%) (g) (g) (g) (g)

______________________________________________________________________________

HAYS

Alfalfa hay, early vegetative Medicago sativa 10 268 90.7 7.4 1.5

Alfalfa hay, late vegetative " " 10 259 81.2 6.3 1.2

Alfalfa hay, mature " " 9 222 35.4 5.1 0.8

Alfalfa meal (17% CP) " " 8 254 78.5 6.4 1.0

Bahiagrass hay Paspalum notatum 9 213 33.6 2.1 0.9

Coastal bermudagrass, early Cynodon dactylon 6 259 68.0 1.8 0.7

Coastal bermudagrass, late " " 9 227 68.0 1.8 0.7

Common bermudagrass (8% CP) " " 9 191 36.3 2.0 0.7

Dallisgrass, midbloom Paspalum dilatatum 9 213 29.5 1.8 0.7

Ryegrass hay, early Lolium multiflorum 11 277 61.7 2.4 1.3

Ryegrass hay, late " " 14 240 39.9 2.4 1.3

GRAINS

Corn grain (8% CP) Zea mays 13 322 36.3 0.2 1.1

Corn, yellow dent (9.5% CP) Zea mays indentata 11 349 43.1 0.1 1.2

Cottonseed meal (41% CP) Gossypium sp. 9 313 186.9 0.8 5.0

Molasses, sugar beet pulp Beta vulgaris altis. 9 304 39.9 2.9 0.4

Molasses, sugarcane Saccharum officin. 25 245 20.0 3.4 0.4

Oats Avena sativa 11 308 53.5 0.3 1.5

Rice bran with germs Oryza sativa 9 286 57.6 0.3 7.0

Sorghum (milo) grain Sorghum bicolor 11 354 46.3 0.1 1.3

Soybean meal (45% CP) Glycine max. 10 358 203.0 1.4 2.9

Wheat germ Triticum aestivum 11 354 64.4 0.2 1.7

ANIMAL PROTEIN

Fishmeal, menhaden (61% CP) Brevoortia tyrannus 8 304 277.1 23.5 13.1

Meat and bone meal (50% CP) 7 299 228.6 46.7 23.1

MINERAL SUPPLEMENTS

Calcium carbonate (CaCO3) 1 0 0 178.7 0.2

Calcium phosphate, dibasic 3 0 0 96.6 84.8

Limestone 0 0 0 154.0 0.1

Oystershell, ground 1 0 0 170.6 0.3

Rock phosphate 0 0 0 145.1 81.6

Sodium phosphate, monobasic 3 0 0 0 98.9

______________________________________________________________________________

Feed Formulation Examples

Example 1

Scenario: Pregnant doe weighs 130 lb, is in late pregnancy, stays in backyard.

DM intake (average = 3.5% of body weight) = 4.55 lb

Requirements:

______________________________________________________________________

Productive Function TDN CP Ca P

______________________________________________________________________

--------------------------g/day---------------------------

Maintenance, low activity, 130 lb 760 105 4.0 2.8

Late pregnancy 397 82 2.0 1.4

Total daily requirement (g/day) 1157 187 6.0 4.2

______________________________________________________________________

Feed Composition:

______________________________________________________________________________

Nutrients provided

Feed ________________________________________

intake,

Feed Ingredient lb/day TDN CP Ca P

____________________________________________________________________________

------------------g/day, as fed basis--------------------

Common bermudagrass hay 2.25 430 81.7 4.50 1.58

Corn, ground 2.00 644 72.6 0.40 2.20

Soybean meal 0.25 90 50.8 0.35 0.73

Total intakea 4.50 1164 205.1 5.25 4.51

____________________________________________________________________________

aAdditional mineral supplementation required (to increase the amount of Ca in the diet).

Comments:

  • If the doe is unable to consume the 4.55 lb/day day and if you know exactly how much she eats, recalculate the feed according to her intake.
  • According to the ration formulated here, the animal will need an additional 0.75 g Ca to fulfill its needs. How much limestone contains 0.75 g Ca?

In 1 lb of limestone = 154.0 g Ca (NRC table)

and 1 lb = 454 g

thus, 454 g limestone = 154 g Ca

and X g limestone = 0.75 g Ca

1. Cross multiply: 154 * X = 340.5 Ca

2. Divide on both sides by 154, solving for X:

154 * X (limestone)/154 = 340.5 (Ca)/154

X (limestone) = 2.211 g

Solved !: You need 2.211 g of limestone to add to the diet to provide the 0.75 g of Ca needed.

Example 2

Scenario: - Very dry pasture (120 g TDN/lb; 25 g protein/lb; 1.4 g Ca/lb; 0.4 g P/lb). Compared with common bermudagrass (191 g TDN/lb; 36.3 g protein/lb), the quality is very low.

- Angora doe weighing 110 lb, produces 13.2 lb of fleece/year, is on pasture and in mid-pregnancy.

- You have bought a pelleted feed containing 60% TDN and 10% protein on an as fed basis. How much of this supplement must you feed your animal, keeping in mind that the grass is "for free" and you want to feed as little as possible of the pelleted feed?

- DM intake at 3.5% body weight = 3.85 lb.

Step 1: Nutrient requirements of the animal.

______________________________________________________________________________

Nutrient Requirements

__________________________________________

Productive Function TDN CP Ca P

______________________________________________________________________________

--------------------------g/day--------------------------

Maintenance, pasture grazing, 110 lb 662 91 4 2.8

Fleece yield, 13.2 lb/year 50 26 - -

Total requirement 712 117 4 2.8

______________________________________________________________________________

Step 2: Nutrient content of the pelleted feed.

60% TDN = 600 g/kg = 600 g/2.2 lb = 273 g TDN/lb feed

10% protein = 100 g protein/kg = 100 g protein/2.2 lb = 45.5 g protein/lb feed

Step 3: Calculate the quantity of pellets needed by first looking at the energy and protein alone.

Pellets Pasture Total

__________ __________ _________

Attempt TDN CP TDN CP TDN CP

______________________________________________________________________

----------------------g/day----------------------

1 (2 lb pellets; 1.9 lb pasture) 546 91.0 228 47.5 774 139

2 (1.7 lb pellets; 2.2 lb pasture) 464 77.3 252 55.0 743 132

3 (1.6 lb pellets; 2.3 lb pasture) 437 72.8 264 57.5 713 130

______________________________________________________________________

Step 4: Calculate the Ca and P contributions from 1.6 lb pellets and 2.3 lb pasture.

Feedstuff Ca P

_______________________________________________

--------g/day---------

2.3 lb pasture 2.99 0.92

1.6 lb pellets 2.18 1.09

Total 5.17 2.01

_______________________________________________

Comments:

The animal requires a further 0.8 g P to fulfill the 2.8 g of P it needs. Checking the Ca:P ratio, it will then be 1.85:1, which is in the recommended range of 1.5:1 to 2:1.

The additional 0.8 g P can be supplied by adding sodium phosphate to the diet.

How much sodium phosphate will provide 0.8 g P?

1 lb sodium phosphate contains 98.9 g P;

therefore, 454 g sodium phosphate = 98.9 g P,

and X g sodium phosphate = 0.8 g P

Multiply diagonally:

98.9 * X = 363.2 g

98.9 * (X sodium phosphate)/98.9 = 363.2/98.9

X = 3.67 g sodium phosphate

Solved!: You need to add 3.67 g sodium phosphate to the diet to fulfill the animal's for phosphate.

Although these examples may not reflect the situation on your farm, the math and reasoning behind them are applicable to many situations. The steps follow one another logically; balance the requirements of the animal and how much it can consume (dry matter) with the nutrients in the feedstuffs available to you. Good luck!

Pertinent References

AFRC. 1998. The Nutrition of Goats. CAB, New York, NY.

Harris, B. 1990. Feeding dairy goats for maximum performance. In: Proc. Florida Dairy Goat Production Conf. pp 5-10. University of Florida, Gainesville.

Landau, S. P., Morand-Fehr, P. Bas, P. Schmidely, and S. Giger-Reverdin. 1996. Nutritional efficiency for conception, pregnancy and lactation in goats with an emphasis on glucose and nitrogen metabolism. In: VI International Conference on Goats Proc. (Vol. 2). pp 528-536. International Academic Publishers, Beijing, P. R. China.

Lu, C. D. 1987. Effect of forage length on milk production in dairy goats. J. Dairy Sci. 70:1411.

Lu, C. D. 1993. Implications of feeding isoenergetic diets containing animal fat on milk composition of Alpine does during early lactation. J. Dairy Sci. 76:1137.

Lu, C. D., M. J. Potchoiba, T. Sahlu, and J. M. Fernandez. 1990. Performance of dairy goats fed isonitrogenous diets containing soybean meal or hydrolyzed feather meal during early lactation. Small Rum. Res. 3:425.

Lu, C. D., M. J. Potchoiba, T. Sahlu, and J. R. Kawas. 1990. Performance of dairy goats fed soybean meal or meat and bone meal with or without urea during lactation. J. Dairy Sci. 73:726.

Morand-Fehr, P. 1996. Recent trends of research on nutrition and feed resources. In: VI International Conference on Goats Proc. (Vol. 2). pp 483-486. International Academic Publishers, Beijing, P. R. China.

NRC. 1981. Nutrient Requirements of Goats. National Academy Press, Washington, DC.

Qi, K., and C. D. Lu. 1996. Sulfur and sulfur-containing amino acid requirements for meat, milk and mohair production in goats. In: VI International Conference on Goats Proc. (Vol. 2). pp 537-548. International Academic Publishers, Beijing, P. R. China.

Sahlu, T. 1992. Recent advances in nutrient requirements for lactating goats and feeding for production. In: T. A. Gipson, S. Hart, and T. Le-Trong (Ed.) Proc. of the National Symposium on Dairy Goat Production and Marketing. pp 31-42. Langston University, Langston, OK.

Sahlu, T., J. M. Fernandez, Z. H. Jia, A. O. Akinsoyinu, S. P. Hart, and T. H. Teh. 1993. Effect of protein level and source on milk production in dairy goats. J. Dairy Sci. 73:2701.

Sahlu, T., S. P. Hart, T. Le-Trong, Z. Jia, L. Dawson, T. Gipson, and T. H. Teh. 1995. Influence of prepartum protein and energy levels for dairy goats on pregnancy and early lactation. J. Dairy Sci. 78:378.

Santini, F. J., C. D. Lu, M. J. Potchoiba, J. M. Fernandez, and S. W. Coleman. 1992. Dietary fiber and milk yield, mastication, digestion, and rate of passage in goats fed alfalfa hay. J. Dairy Sci. 75:209.

Smuts, M., and T. Sahlu. 1995. Effects of prepartum doe dietary protein and energy intake on performance and blood characteristics of precolostral Alpine kids. Sheep Goat Res. J. 11:35.

The proper citation for this article is:
Sahlu T. and A. Goetsch. 1998. Feeding the Pregnant and Milking Doe. Pages 4-20 in Proc. 13th Ann. Goat Field Day, Langston University, Langston, OK.


 

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