Pregnancy Nutrition: Weight Change and Calories
Cravings should not be the sole indicator of nutritional needs. You need to turn off or at least slow down the flow of information and, instead, focus on acquiring the RIGHT information that will give you clarity and a deeper understanding to move you closer to your health goals. The Report is delivered by an Independent Expert Group and guided at a strategic level by a Stakeholder Group , whose members also reviewed the Report. The challenge is huge, but it is dwarfed by the opportunity. For FSR diagnostic work, simple measurements that can be made on certain long bones at slaughter can provide results which are generally more reliable than those obtained from blood samples. I like that the material is presented in different ways. If the district has not received a SMI review from the state agency within the past five years, the district will request from the state agency that a SMI review be scheduled as soon as possible.
CLICK A FOOD GROUP TO EXPLORE
If nutrition is identified as the critical constraint to performance, further studies on specific aspects of nutrition related to the animal or the feed may be needed. The various methods used to assess animal production performance are discussed in Module 5, and the reader should refer to it if detailed diagnosis of production performance is envisaged.
For instance, there may be data available from range evaluation and animal production studies and farm management surveys, which specifically identify nutrition as the critical constraint to production. Feed intake Intake, or the amount of feed an animal consumes, can be estimated by using either digestibility data or 'markers'. When such data are available, intake can be estimated by multiplying the dry-matter weight of faeces by a digestibility factor.
The factor is known as the feed: Digestibility and intake data can be derived from the indigestible components of a diet, known as 'markers'. Markers are classified as internal, if they are ordinarily present in the diet e.
Synthetic organic substances such as beads, rubber and ribbon have also been used, since they can be easily separated from the feed. Van Soest provides a detailed account of the various markers used to estimate intake and digestibility, and of their advantages and disadvantages. The term 'indicator' is sometimes used instead of 'marker' Dicko-Touré, , Church and Pond, ; Lambourne et al, The formula to estimate faecal output is: An animal is dosed with 50 g of chromic oxide per day to determine its daily faecal output.
The concentration proportion of marker in the dry-faeces sample is 5. The dry-matter weight of faeces excreted per day is g and 5. The proportion of the marker in the diet is 3. Calculate the DM intake of the animal. These can then be related to such variables as seasonal rainfall, stocking rate, management practices or plant composition to isolate its main determinants. Summary The normal procedures to estimate DM digestibility and intake are to: This requires the further estimation of faecal output either by total faecal collection or dosing with known quantities of, for instance, chromic oxide.
When facilities for laboratory analysis are not available or are inadequate, intake should be calculated on the basis of digestibility. Simple methods to estimate digestibility are given in the text which follows.
Composition of consumed feed There are various methods used to determine what the animal is eating. Those discussed here are: The botanical composition of feed consumed by an animal can be determined by using a surgical fistula inserted into an animal's oesophagus. The food eaten passes into a collection bag attached to the neck, and samples are taken directly from the bag after allowing the animals to graze for not more than two hours before re-inserting the fistula plug. The oesophageal fistula method provides an accurate indication of the botanical composition of the feed consumed.
An illustration of this type of approach is given by McLean et al However, because of salivary contamination of the samples, accurate direct estimates of the chemical composition of feed eaten are restricted to nitrogen, neutral detergent solubles, calcium, magnesium, sulphur and copper Little, ; Dietary phosphorus concentrations can be estimated accurately only from oesophageal extrusa labelled with radioactive P Little et al, It also tends to be time-consuming and costly, and farmers are unlikely to cooperate when their own stock is involved.
Nevertheless, ILCA research workers have used the method in the field. In Kenya, for instance, oesophageal fistulae were fitted to cows which had been purchased from Maasai pastoralists and herded with farmers herds during three seasons in several locations Semenye, a, b. The data obtained on feed composition were then complemented by studies on grazing behaviour of the type discussed below.
Material collected with the fistula method can be used in the determination of digestibility by in vitro estimation procedures see page This method is applicable to both cattle and smallstock and allows direct sampling of the contents of the rumen by means of a cannula surgically inserted into the rumen. It involves physically emptying the contents of the rumen by hand before the animal goes to graze and then taking samples from the freshly ingested material two to three hours after the animal started grazing.
It is therefore more likely to be applicable to on-farmlon-range experiments described in Section 2. Direct observation of grazing habits. The content of food consumed by grazing animals can be guesstimated by following selected animals in a herd or flock at distances which are close enough to observe what is being eaten.
Each selected animal is observed at regular intervals. Two field examples demonstrate the principles. De Leeuw and Chara used the technique to compare goat and sheep browse preferences in mixed Maasai flocks in Kenya. Observations were carried out during the dry season with randomly selected animals being followed for periods of one to two hours by one or two observers who were familiar with the local flora.
Because the animals were familiar with humans, observations could be made at distances of m. The aim was to obtain an equal number of 'hits' for sheep and goat - a 'hit' occurring each time a particular plant species was eaten. Hits per plant species were then summed and compared with the total number to determine the proportion of each plant eaten.
These figures were then used to derive an index of preference or selection. Between and hits were collected for both sheep and goats in each sample flock. Nyerges observed the grazing habits of sheep, by following each for a period of 20 minutes measured by stop watch. Animals were followed at distances of m and the shrub and ground species consumed including ground litter during the observation period were recorded. Direct observation can also be applied to other studies of animal grazing behaviour, e.
These variables can then be related to such parameters as intake, digestibility, stocking rate and distance to water, to isolate the more important determinants of grazing behaviour Lambourne et al, , pp. A modification of the direct-observation method was used by Dicko-Touré in Mali to determine the composition of feed consumed.
Selected animals were followed for a period of one minute, and distance walked as well as the number of mouthful taken during this period were recorded. A sample of forage was then collected by hand from the area grazed during the one-minute observation period.
The size of the sample taken was in proportion to the observed number of mouthfuls one hand-grab for every five mouthful. Similar measurements were made for each selected animal every 45 minutes throughout the day in order to obtain comprehensive data on feeding habits and feed composition. Lambourne et al argued that, for most purposes, such rapid-survey techniques provide sufficient detail on diet composition. They are low-cost, require minimal supervision and can be completed in a relatively short time.
Observers should, preferably, have a good knowledge of local flora, but it is more important for them to be observant. If hand samples are collected to mimic grazing habits, these can be analysed at a later stage by someone who is thoroughly familiar with the flora. Data on diet composition can be complemented by opinions obtained from herdsmen in the area.
Their knowledge about species differences in terms of selectivity and palatability is often very precise. Pasture analysis before and after grazing. The 'before' and 'after' method involves the demarcation of quadrats in a paddock before and after animals are released into an area for grazing Figure 4. Adjacent to each fenced quadrat is an equally sized area, with similar vegetation characteristics. The biomass and vegetation composition of the two 'paired' areas are measured using one of the techniques described in Module 6 and animals are then released into the area to graze t'Mannetje, Schematic representation of the pasture analysis method.
After a prescribed period e. The method will give reasonable estimates provided that the two areas are not highly variable in terms of species composition. When vegetation is highly variable, the number of paired samples required must be increased, making measurement more time-consuming.
Faecal samples have been used for microscopic analysis of the plant part they contain, to provide an indication of the vegetation consumed by an animal Stewart, However, as an indicator of dietary composition such samples tend to be unreliable since the indigestible portion of the diet may bear little relationship to the portion actually consumed. The faeces may, for instance, contain high proportions of woody ligneous material consumed during browsing.
This does not necessarily mean that the diet also contains similar proportions of this component. Feed digestibility The methods used to assess digestibility are based on: Of these, only the first three are relevant to the diagnostic phase of livestock systems research.
The in vivo method is more applicable to on-station research and involves intensive laboratory work and careful supervision. The use of markers. When it is impossible or inconvenient to measure total feed intake or to collect total faeces, markers can be used to determine intake see pages as well as digestibility.
The formula used to calculate apparent digestibility 16 is: Calculate the apparent digestibility of the feed. To obtain data for the analysis based on markers, follow this procedure: There are two obvious sources of error in such a methodology. First, lignin may be partly digestible and is thus not always a reliable indicator marker.
Second, the feed samples taken will often be not truly representative of actual intake, particularly when pasture is highly variable, and where the choice of samples is entirely dependent on the enumerator judgement. There are various methods available to sample faecal output in the field, including: This method is practical in a range context. Schneider and Flatt, However, Dicko-Touré, , p. She argued that the costs of using indicators to estimate faecal output would, in fact, have been more expensive since this method would have involved sending samples to another country at a cost that is at least 10 times higher than the cost actually incurred by using the bag-collection method.
Thus, the methods adopted in any diagnostic study to sample faecal output should be tailored to the particular circumstances of the study, bearing in mind the financial and manpower resources of the research team. The use of faecal indices. The methods using faecal indices to estimate digestibility are based on established regression relationships between faecal indices and the digestibility of dry or organic matter Van Soest, The general model for these relationships is: The two variables merely happen to go together i.
The estimation of digestibility via faecal indices involves the following steps: The main advantages of this method are that it is relatively low-cost and results can be obtained fairly quickly. Its chief disadvantage is that it is site-specific, and the derived parameters and relations In vitro analysis of consumed feed. When digestibility is analysed by in vitro methods, samples of feed ingested are subjected to artificial tests which simulate digestibility under controlled conditions.
The more commonly applied methods involve the use of rumen fluids, chemical fermenters and nylon bags see Church and Pond, Rumen fluids are extracted from rumen-fistulated animals and used in combination with buffers to simulate the action of saliva.
The Tilley-Terry method, which is widely used, involves an additional stage in which the feed is further digested with acid pepsin for another 48 hours. The residual represents the indigestible portion of the feed.
Chemical fermenters added to the feed have been used to predict digestibility. The method is also used to study rumen function and the metabolism of certain compounds, e. The advantage of the two methods is that the analysis is not expensive if laboratory facilities are available and that it can be performed fairly quickly.
The methods can also be used to assess the digestibility of grab samples of grass or of cut samples of stover and straws taken after crop harvesting. These are inserted into the rumen of test animals and removed after a prescribed period. The loss of material from the bag as a result of fermentation is then calculated. The method is more applicable to on-station research, but it can be used together with the rumen cannula method to determine intake. Nutritive value of feed This part of the module focuses on the methods and techniques used in estimating the supply of different nutrients to animals in particular situations or systems, in relation to their need for these nutrients.
It starts with a general section on estimating the main feed components. It then goes straight to fibre analysis because of the difficulties involved in estimating feed values in very fibrous diets. Finally, it looks at some of the techniques in use for the physical sampling, from stands of different kinds of feed, for laboratory analysis. Methods to estimate feed components The feed value of a source of feed can be assessed on the basis of its energy value, crude protein content and mineral content, using methods specifically designed to estimate these components of feed.
The energy yield of a source of feed such as natural pasture can be estimated from its dry-matter weight per unit area. Module 6 discusses the various methods used to estimate biomass or dry-matter weight under rangeland conditions.
Many of these methods rely on the use of predictive equations based on the relationship between biomass and the vegetation characteristics e.
Samples can be taken to establish similar predictive relationships for the estimation of dry-matter weight of crop residues. Powell , for instance, used grain yield to predict total stover dry-matter weight and stalk and leaf dry-matter weights for millet and sorghum.
The relationships, which were based on data obtained from randomly chosen sites in Kaduna State, Nigeria, were highly significant Figure 5. Van Raay and de Leeuw adopted a similar procedure to determine the DM weight of crop residues in Katsina, Nigeria. They established predictive relationships on the basis of stalk and stand density, plant height and plant edibility subjectively estimated.
Relationships between sorghum and millet grain yields and stover dry-matter DM yields. Having obtained an estimate of dry-matter yield, an estimate of digestibility is then required before the desired approximation of the energy yield can be calculated.
The fibrous portions of a feed must, therefore, be considered before more accurate estimates of nutritive value can be made. Feeds with a high biomass per unit area are often low in energy since they also contain a high proportion of indigestible fibrous matter.
Methods of fibre analysis have been devised to separate those portions of fibre which can be utilised by the ruminant from those which are essentially indigestible. Fibre analysis is thus particularly important in the assessment of the nutritive value of these feeds. For the purposes of illustration, however, the following average relationships can be used: Let us calculate the feed energy requirements of a kg liveweight ox for maintenance, foraging and production, and compare these with the availability of energy to that animal from its feed supply.
The maintenance fasting metabolism requirement is determined as follows: Km tends to lie in the range 0. We can call this 'foraging'. The energy requirement for foraging Ef are given by the formula: To gain weight, an animal needs between 12 and 27 MJ of ME per kg liveweight, depending on the percentage that fat constitutes in the meat accumulated. We can now compare supply and requirements of feed energy per ox for the 90 days of the dry season as follows: The standard laboratory method for the estimation of crude protein is the Kjeldahl method which is described in most texts on animal nutrition e.
McDonald et al, ; Church and Pond, The analysis is used to determine the crude protein content of a sample of grass or stover, and the results can then be used to establish predictive regression equations similar to those illustrated in Figure 5. When estimating the crude protein content of browse plants and crop residues, it should be borne in mind that the presence of certain phenolics tannins in these feeds can affect the availability of nitrogen to the ruminant.
This is particularly true of feeds high in insoluble polyphenolics, for which the calculated crude protein content may overestimate the amount of nitrogen which can actually be synthesised into protein e. Woodward and Reed, Analysis should only be attempted if mineral deficiencies are clearly evident. Even then, if other nutrients such as energy or crude protein are more limiting as is likely to be the case on African rangelands , the mineral constraint should be dealt with only after the primary deficiencies have been rectified Little, The methods used by ILCA researchers to diagnose the more common deficiencies involve blood, bone, liver, milk and faecal samples and are discussed in general terms below.
All the methods outlined rely on adequate laboratory facilities. For a more detailed account of symptoms of mineral deficiency and the role of minerals in animal nutrition, the user is referred to basic nutrition texts, e. Cullison and Church and Pond Whole blood, blood serum and blood plasma samples have been used to diagnose mineral deficiencies particularly phosphorous and magnesium in livestock. Values significantly below 'normal' concentrations or ranges indicate the nutritional status of an animal with respect to a particular mineral, but the evidence is not always conclusive McDowell et al, Precautions must, for instance, be taken when samples are taken in less than optimum conditions since exercise, stress, temperature and other factors can alter mineral concentrations.
Such factors are often difficult to control in African conditions Mtimuni, and have resulted in high concentrations of phosphorous in serum when the concentration in forages consumed was, in fact, extremely low. Little et al described a method for obtaining accurate estimates of blood inorganic P concentrations, but the difficulties of interpretation of such data were noted by Gartner et al Basically, only low blood inorganic P values have any diagnostic value.
Because of the problems just described, tests using bone samples have been developed to test for phosphorus deficiency in livestock. Samples of rib bone can be obtained by simple surgery. For FSR diagnostic work, simple measurements that can be made on certain long bones at slaughter can provide results which are generally more reliable than those obtained from blood samples. These methods have been described by Little Liver samples have been used to diagnose for copper, cobalt and vitamin A deficiencies in African livestock Tartour, ; van Niekerk, ILCA has used samples of milk to diagnose mineral deficiencies in cattle in Ethiopia.
However, since milk composition is influenced by such factors as cow age, stage of lactation and genetic potential, milk sampling tends to be unreliable. The 'let-down' problem associated with zebu cattle Module 5 also means that it is cliff cut to obtain representative samples in field studies.
Large variations in butterfat content between successive milkings of the same cow reflect this problem Lambourne et al, However, milk samples are very useful in the diagnosis of iodine deficiency Committee on Mineral Nutrition, Apart from their use in digestibility and intake studies, faecal samples have been used to diagnose for phosphorus and sodium deficiencies Little, A vegetable is not considered a grain, fruit, nut , spice , or herb.
For example, the stem , root , flower , etc. Vegetables contain many vitamins and minerals ; however, different vegetables contain different spreads, so it is important to eat a wide variety of types. For example, green vegetables typically contain vitamin A , dark orange and dark green vegetables contain vitamin C , and vegetables like broccoli and related plants contain iron and calcium. Vegetables are very low in fats and calories , but ingredients added in preparation can often add these.
These foods provide complex carbohydrates, which are a good source of energy but provide little nutrition. While they may serve as a filler in low-fat meal plans, replacing these with nuts and seeds would be a better option. Examples include corn , wheat , pasta , and rice.
In terms of food rather than botany , fruits are the sweet-tasting seed -bearing parts of plants, or occasionally sweet parts of plants which do not bear seeds. These include apples , oranges , grapes , bananas , etc. Fruits are low in calories and fat and are a source of natural sugars , fiber and vitamins. Processing fruit when canning or making into juices may add sugars and remove nutrients.
The fruit food group is sometimes combined with the vegetable food group. Note that a massive number of different plant species produce seed pods which are considered fruits in botany, and there are a number of botanical fruits which are conventionally not considered fruits in cuisine because they lack the characteristic sweet taste, e. A food pyramid's tip is the smallest part, so the fats and sweets in the top of the Food Pyramid should comprise the smallest percentage of the diet.
The foods at the top of the food pyramid should be eaten sparingly because they provide calories, but not much in the way of nutrition. These foods include salad dressings, oils, cream, butter, margarine, sugars, soft drinks, candies, and sweet desserts.
Dairy products are produced from the milk of mammals , usually but not exclusively cattle. They include milk, yogurt and cheese.
Milk and its derivative products are a rich source of dietary calcium and also provide protein, phosphorus , vitamin A, and vitamin D. However, many dairy products are high in saturated fat and cholesterol compared to vegetables, fruits and whole grains, which is why skimmed products are available as an alternative. Historically, adults were recommended to consume three cups of dairy products per day. For example, recent research has shown that dairy products are not related to stronger bones or less fractures; on the flip side, another study showed that milk and yogurt consumption results in higher bone mineral density in the hip.
Overall, the majority of research suggests that dairy has some beneficial effects on bone health, in part because of milk's other nutrients.
Meat is the tissue — usually muscle — of an animal consumed by humans. Since most parts of many animals are edible, there is a vast variety of meats. Meat is a major source of protein , as well as iron, zinc , and vitamin B Meats, poultry, and fish include beef , chicken , pork , salmon , tuna , shrimp , and eggs.
The meat group is one of the major compacted food groups in the food guide pyramid. Many of the same nutrients found in meat can also be found in foods like eggs , dry beans , and nuts , such foods are typically placed in the same category as meats, as meat alternatives.
These include tofu , products that resemble meat or fish but are made with soy , eggs , and cheeses. For those who do not consume meat or animal products see Vegetarianism , veganism and Taboo food and drink , meat analogs , tofu , beans, lentils, chick peas, nuts and other high-protein vegetables are also included in this group. The food guide pyramid suggests that adults eat 2—3 servings per day.
In April , the U. This incident was only one of many in which the food industry attempted to alter federal dietary recommendations in their own economic self-interest. Some of the recommended quantities for the different types of food in the old pyramid have also come under criticism for lack of clarity. For instance, the pyramid recommends two to three servings from the protein-rich group, but this is intended to be a maximum.
The pyramid recommends two to four fruit servings, but this is intended to be the minimum. The fats group as a whole have been put at the tip of the pyramid, under the direction to eat as little as possible, which is largely problematic.
School policies concerning safety will apply at all times. The superintendent or designee will ensure compliance with established district-wide nutrition and physical activity wellness policies. School food service staff, at the school or district level, will ensure compliance with nutrition policies within school food service areas and will report on this matter to the superintendent or if done at the school level, to the school principal.
If the district has not received a SMI review from the state agency within the past five years, the district will request from the state agency that a SMI review be scheduled as soon as possible. The superintendent or designee will develop a summary report every three years on district-wide compliance with the district's established nutrition and physical activity wellness policies, based on input from schools within the district.
To help with the initial development of the district's wellness policies, each school in the district will conduct a baseline assessment of the school's existing nutrition and physical activity environments and policies. Assessments will be repeated every three years to help review policy compliance, assess progress, and determine areas in need of improvement. As part of that review, the school district will review our nutrition and physical activity policies; provision of an environment that supports healthy eating and physical activity; and nutrition and physical education policies and program elements.
The district, and individual schools within the district, will, as necessary, revise the wellness policies and develop work plans to facilitate their implementation. Schools are encouraged to source fresh fruits and vegetables from local farmers when practicable. Examples include "whole" wheat flour, cracked wheat, brown rice, and oatmeal. The school district will engage students, parents, teachers, food service professionals, health professionals, and other interested community members in developing, implementing, monitoring, and reviewing district-wide nutrition and physical activity policies.
All students in grades K will have opportunities, support, and encouragement to be physically active on a regular basis. Foods and beverages sold or served at school will meet the nutrition recommendations of the U. Dietary Guidelines for Americans. Qualified child nutrition professionals will provide students with access to a variety of affordable, nutritious, and appealing foods that meet the health and nutrition needs of students; will accommodate the religious, ethnic, and cultural diversity of the student body in meal planning; and will provide clean, safe, and pleasant settings and adequate time for students to eat.
Schools will provide nutrition education and physical education to foster lifelong habits of healthy eating and physical activity, and will establish linkages between health education and school meal programs, and with related community services. To ensure that all children have breakfast, either at home or at school, in order to meet their nutritional needs and enhance their ability to learn: Schools will, to the extent possible, operate the School Breakfast Program.
Schools will, to the extent possible, arrange bus schedules and utilize methods to serve school breakfasts that encourage participation, including serving breakfast in the classroom, "grab-and-go" breakfast, or breakfast during morning break or recess.
Schools that serve breakfast to students will notify parents and students of the availability of the School Breakfast Program. Schools will encourage parents to provide a healthy breakfast for their children through newsletter articles, take-home materials, or other means.
Meal Times and Scheduling. Foods and Beverages Sold Individually i. View Additional Resources Elementary Schools. Foods A food item sold individually: One and one-quarter ounces for chips, crackers, popcorn, cereal, trail mix, nuts, seeds, dried fruit, or jerky; One ounce for cookies; Two ounces for cereal bars, granola bars, pastries, muffins, doughnuts, bagels, and other bakery items; Four fluid ounces for frozen desserts, including, but not limited to, low-fat or fat-free ice cream; Eight ounces for non-frozen yogurt; Twelve fluid ounces for beverages, excluding water; and The portion size of a la carte entrees and side dishes, including potatoes, will not be greater than the size of comparable portions offered as part of school meals.
Fruits and non-fried vegetables are exempt from portion-size limits. View Additional Resources Snacks. If eligible, schools that provide snacks through after-school programs will pursue receiving reimbursements through the National School Lunch Program.
View Additional Resources Rewards. View Additional Resources Celebrations. View Additional Resources School-sponsored Events such as, but not limited to, athletic events, dances, or performances.
Schools should provide nutrition education and engage in nutrition promotion that: View Additional Resources Communications with Parents. View Additional Resources Staff Wellness. View Additional Resources Daily Recess.