Egg Whitebased Products

The foaming capability of egg albumen is the fundamental characteristic of this product group. They are used mainly in baked products prepared at 350 400oF or in foamy drinks and desserts. They are available commercially in ready-to-cook or ready-to-eat forms. 1. Angel cake is made from egg whites, flour, and sugar. The egg whites and sugar are beaten until solidified and the flour is then added. The mixture is poured into a baking pan. No leavening agents are used. This cake is also used as a...

Community Impacts And Responses

Two central community concerns associated with the existence and expansion of CAFOs are their environmental and economic impacts. In the case of the environment, the concentration of large numbers of livestock in relatively small geographic areas contributes to concerns about manure management, water quality, odor, and air quality. 4,5 Neighbor concerns about livestock odors, as they impact human health and quality of life, may be the most serious concern for the immediate neighborhood...

Mating Systems To Exploit Heterosis

In many cases, the value of an animal's genes to its progeny depends on the genes contributed by its mate. This is true for nonlinear merit traits, for which corrective mating systems can be used. However, the classic case is that the value of an animal may be higher if its mates are of a different breed, because the progeny will be more heterozygous and will exhibit heterosis. Three types of crossbreeding system can be defined, according to the incidence of purebreds in the breed pedigree...

Other Factors

Dairy farmers continue to make additional genetic improvement by culling within the herd. Herd replacements often allow a turnover of about 30 of milking animals per year. Some culling decisions are under the manager's voluntary control, but others may be driven by fitness traits that limit the animal's ability to remain profitable and stay in the herd. A cow must be capable of timely pregnancies so that a new lactation can begin and Table 1 Relative emphasis of traits in selection indexes from...

The End Of Husbandry

Symbolically, this contract was broken in the mid-20th century when academic departments of animal husbandry changed their names to departments of animal science. As the textbooks put it, animal science became ''the application of industrial methods to the production of animals.'' This change occurred in America for a variety of reasons. 1 With projections of burgeoning population and shrinking amounts of agricultural land, agricultural scientists feared shortages in the food supply. The...

Food Production And Land

Location of food production in the world is affected by people and land resources. The suitability of the land for Fig. 1 Urban and rural interface the coexistence of the human population and commercial food animal production. (View this art in color at www.dekker.com.) Fig. 1 Urban and rural interface the coexistence of the human population and commercial food animal production. (View this art in color at www.dekker.com.) food production is very important, and the availability of technology to...

Environmental Impacts

As the structure of agriculture changes, animal production facilities are increasing in scale. Larger numbers of confined animals are raised on fewer farms. More are clustering around feed mills and processing plants. These trends have led to growing public concern about the impact of agricultural land use on ground and surface water quality. 4 Nationwide, the Clean Water Act addresses the potential water quality impacts of large-scale animal agriculture. Concentrated animal feeding operations...

Flow Sorting System

As the liquid stream containing sperm exits the sorter nozzle, it is vibrated at about 75,000 to 85,000 oscillations sec to break the stream into individual droplets. 9 Although not all of these formed droplets contain sperm, those that do are electrically charged, either positive or negative, according to the DNA content information previously provided by detector. Droplets containing improperly oriented sperm, more than one sperm, or dead sperm, as determined by uptake of a vital dye, are...

Mycotoxins

Aflatoxins are produced by molds growing in corn, peanuts, and other grain and pulse crops. This widespread toxicant can cause reduced feed intake and both acute and chronic liver damage. Highly carcinogenic, this is one of the few important natural toxins that can pass into animal products in sufficient amounts to threaten human health. Zearalenone, which is produced by a different mold in corn, is a powerful estrogen analogue that can cause feminization of male animals and disruption of...

Farmland Preservation

Citizens and state and local leaders are concerned with the amount and location of land available for farming. Beyond the need for food production, the reasons for preservation include reducing the cost of infrastructure and amenities associated with providing open space. 7 Special treatment of agricultural land is usually sought through traditional land use controls such as zoning and subdivision, with special modifications. For example, exclusive agricultural zoning, which does not allow any...

Biological Basis Of Sperm Sexing

Separation of sperm according to the sex chromosome is based on the DNA content of the sperm. Mammalian semen can be sexed because the X-chromosome-bearing sperm that produce females contain about 4 more DNA than do the Y-chromosome-bearing sperm that produce males. The procedure is 85-95 accurate for the selected sex. 1-3 Sorting of live mammalian sperm according to their DNA content first was developed the USDA Beltsville Agricultural Research Center. 4 This flow cytometric sorting procedure...

Nuisance Impacts

Every state has passed some form of right-to-farm law. These laws encourage working agricultural lands, and typically aim to protect farmers from nuisance lawsuits filed by neighboring land owners. 5 A nuisance is an activity that unreasonably interferes with or disturbs a person's use and enjoyment of their own property.1-6-1 Some right-to-farm laws restrict local governments from regulating generally accepted normal farming practices, which can be difficult to define. For example, is it...

Reproduction

Angora goats have a reputation for low reproduction rates. This causes problems for the producer in terms of lost income from sale of excess animals, making progress in herd improvement, and maintaining herd numbers. There are various reasons for low reproductive efficiency. The most important is inadequate nutrition at one or more stages of growth or during the reproductive cycle. Many reproductive problems can be cured with adequate nutrition and or increased management inputs that must be...

Biosecurity

Biosecurity is a major responsibility of the farm health team, and awareness of the ease of disease spread is required for all members of the team. It is impossible (at present) to prevent the transmission of some diseases, for example, various serotypes of Escherichia coli or earth-borne pathogens such as Erysipelothrix rhusiopathiae. Some diseases may spread long distances through the air, for example, parvovirus. Other pathogens are only locally spread. Mycoplasma hyopneumoniae, for example,...

Vaccination

Basic vaccination programs for goats include vaccinations against Clostriduim perfringens types C and D and Clostridium tetani. 1'3'6 There are multivalent clostridial vaccines, including those against black leg, malignant edema, and bacillary hemoglobinuria, used in goats. These are unusual diseases in goats, and vaccination to prevent them is usually not economically justified. Vaccines against contagious ecthyma, caseous lymphadenitis, and Chlamydia are incorporated in the vaccination...

Sexual Performance Motivation And Stimulation Of Males

Within a species, motor patterns associated with courtship and copulation are species-specific and relatively invariant, although the sequence of behaviors exhibited varies within and among individuals. Large variation in the frequency or intensity of displays of sexual behavior does occur in farm animals and is likely due to relaxation of natural selection. 2,3 For example, single-sire mating systems enable animals with poor sexual performance to produce large numbers of offspring. This would...

Laying Hens

In the United States, about 99 of laying hens are housed in so-called battery (or conventional) cages (Fig. 1). This type of housing provides the hen with protection against predators and soil-borne diseases, and although hens are kept in natural-sized social groups of 3 10 birds, their behavior is also restricted. A space allowance of about 72 in2 is required for a hen to be able to stand, turn around, and lie comfortably, although hens may be given less than this amount. Even more space is...

Decision Support Systems

Mathematical models coupled with databases containing necessary, but often difficult-to-access, input information and with a straightforward user-interface can provide individual producers insight into their production system that was previously unavailable. These applications of mathematical models allow individuals to pose and answer what-if questions in a matter of minutes rather than over the course of years, as would be required to address the same questions using the actual production...

Hepatotoxins

A wide variety of feed toxins specifically attack the liver. Usual symptoms of liver damage such as jaundice (or, icterus) and elevated liver enzymes in the blood may be present, but usually the first symptoms noticed are severe damage to the skin on exposure to sunlight. Liver damage can become fairly advanced before stock owners notice their animals are behaving as if they are ill, so blood may not be drawn or the color of membranes assessed in the early stages. But when the liver has been...

Muscle Distribution

Given that mature size is the primary trait affecting the amount of muscle at a particular weight, the other possible effect on carcass value could be differences in muscle distribution. In their classic book on cattle growth, Berg and Butterfield 7 summarized several studies of dissec-tible muscle distribution of breeds with widely different conformations. Data from one of those studies are summarized in Table 2. Similar data were summarized for sheep by Butterfield. 2 The breeds in Table 2...

Breeding Management

Primarily for economic reasons, mares are bred to have their foals during the months of January through May (Northern Hemisphere). However, horses are long-day breeders that have optimal reproductive success from April through July. The equine reproductive cycle is entrained to daylength (photoperiod) therefore, estrus can be induced earlier in the year by using an artificially lengthened photoperiod. The daily schedule should provide approximately 16 hours of light (natural plus artificial)...

Genetic Evaluation Systems

Accurate methods for evaluating genetic merit of bulls and cows for economically important traits are needed to identify those animals that are best suited to be parents of the next generation. The degree of system sophistication needed depends partially on effectiveness of the sampling program in randomizing bull daughters across herds that represent various management levels. If randomization is Fig. 1 Numbers of U.S. cows and mean milk yield by year. (Source Animal Improvement Programs...

Egg Products From Breaking Operations

Egg-breaking operations were established in order to open an outlet for surplus eggs, small eggs, cracked eggs, and dirty eggs and to provide relatively long shelf life products for bakers and confectioners who were the main users until World War II (WWII). Today, the entire production of some farms is fully directed to egg breaking. In other egg farms, most of the medium eggs are also directed to breaking, and larger eggs are sent to the fresh egg market. Prior to 1940, breaking operations...

Neuroendocrine Responses

The neuroendocrine responses to stressors are important adaptation and coping mechanisms that occur in response to a threatening stimulus. The adaptive changes initiated by stressors involve activation of the hypothalamic-pituitary-adrenal (HPA) axis. The hypothalamus and the --Glucocorticoids J J Catecholamines --Glucocorticoids J J Catecholamines Fig. 1 This diagram depicts the activation of the HPA axis in response to stress. The response is perceived and organized in the CNS, which in turn...

Microbial Effects On Host Animals

Table 2 Common bacteria in the hindgut of pigs Bacteroides fragilis Bacteroides thetaiotaomicron Bacteroides uniformis Bacteroides suis Butyrivibrio fibrisolvens Clostridium perfringens Escherichia coli Eubacterium aerofaciens Fibrobacter succinogenes Lactobacillus acidophilus Lactobacillus brevis Lactobacillus cellobiosus Lactobacillus fermentum Lactobacillus salivarius Methanobrevibacter spp Peptostreptococcus productus Prevotella bryantii Prevotella ruminicola Proteus spp Ruminococcus...

Dual Energy XRay Absorptiometry

A different attenuation of low- and high-energy X-rays by fat and nonfat or bone tissues is the basic principle for the measurement of body composition by dual energy X-ray absorptiometry (DXA). The fat and lean (nonfat) content is determined for each pixel of a scan that does not overlie bone and is reported to be virtually independent of tissue thickness. In addition to whole-body or regional composition values of fat and lean content (Fig. 1), DXA provides estimates for bone mineral content,...

The Flock

Reproductive management is all-encompassing with respect to the flock. In other words, in addition to the primary factors of genetics and environmental influences, the role of both the ram and the ewe must be taken into account for successful replication of their species and or breed. When considering reproductive management of sheep, it should be reviewed within the context of gender management because of the uniqueness and functionality of both rams and ewes within the broad scope of sheep...

Prebiotics

Prebiotics are nondigestible food ingredients that benefit the host by promoting the growth of beneficial bacteria in the gastrointestinal tract. Beneficial species of bacteria such as bifidobacteria and lactobacilli readily ferment the prebiotic oligosaccharides (oligofructose and inulin), whereas pathogenic bacteria such as Salmonella and E. coli do not. 4 The potential of prebiotics to replace antimicrobials for pathogen control or performance enhancement has not been proven conclusively,...

Whole Egg Products

Hard-cooked eggs are made by placing the egg in vertical position in cold water and bringing it to a boil. Then the eggs are simmered for about 10 minutes, rapidly cooled down, and peeled manually or mechanically by machines, which today have a capacity for up to 70,000 eggs hour (Fig. 1). Products are sold with or without peel in liquid- containing packages in dry plastic that is either flexible or rigid. These packages contain as few as 2 eggs up to 5 gallon drums for institutional use. 2....

Performance Recording

Little genetic improvement can be achieved without objective measurement of traits targeted for improvement. Countries vary considerably in percentage of cows that are in milk-recording programs. In the United States, slightly less than 50 of dairy cows are enrolled in a dairy records management program that supplies performance records to the national database, and parentage of only about 65 of those cows is known. The first traits to be evaluated nationally in the United States were milk and...

Inspection

Inspection laws and regulations pertaining to poultry were not enacted in the United States until the late 1900s because most of the poultry was produced by farmers on a small scale and sold, either live or dressed, at local markets. As poultry production and consumption increased during the last five decades, several agencies, acts, and programs were introduced by the federal government to define, regulate, and enforce inspection activities (Table 1). The Poultry Products Inspection Act of...

Security

Breakdown of nitrogen storage vessels is the most common catastrophe facing frozen storage. Another crisis can arise from outbreak of notifiable animal disease (e.g., foot-and-mouth disease in the U.K.) resulting in a movement restriction of material in or out of the store while this persists, the bank becomes unusable. Apart from proper alarms fitted to storage dewars, it is a good policy for the collection to be divided between two storage sites geographically separated from each other.

Why Accommodate

The first question that needs to be addressed is Why should we accommodate the needs of livestock The idea that livestock are for our use, and therefore, it is they that must accommodate to our needs, is flawed simply because often livestock are unable to accommodate. This inability to accommodate is due to characteristics that are hardwired, innate, or instinctual. These words mean that livestock have needs that are determined by their genetic makeup, thus they can not be altered. It is in the...

Calendar Of Operations

In Texas, Angora does are bred in October to kid in March. Two to three weeks before and after males are introduced (one male to 20 25 does), does may be supplemented nutritionally to enhance ovulation rates. Throughout winter, range and forage conditions are evaluated in conjunction with the body condition of does so that a timely decision on required supplementation can be made. Also, internal parasites are monitored so the goats can be treated with anthelmintics after first frost, when fecal...

Embryo Sexing

Microsurgical methods have been developed to extract individual cells (blastomeres) from early stage embryos. The cells remaining in the biopsied embryo generally survive and develop into a viable offspring. The individual cells removed from both early- and later-stage embryos can be used to determine the sex of each embryo prior to its transfer to a recipient female. Embryo sexing using the DNA amplification procedure known as the polymerase chain reaction (PCR), with specific Y-chromosome DNA...

Otariidae Eared Seals

The fur seals and sea lions (family Otariidae) have resolved the conflict between marine foraging and terrestrial nursing in a strikingly different manner. Although mothers initially haul out onto land to give birth and remain ashore for 1 1.5 weeks, they then begin a series of periodic foraging trips to sea interspersed with 1 4-day nursing periods ashore. Depending on species and pupping site, the foraging trips may be of remarkable length, from less than 1 day to more than 20 days. 1,2 The...

Natural Dietary Habits

When observed for a sufficient period, omnivory is clearly a combination of carnivory and herbivory. The proportions of animal and plant foods consumed by omnivorous mammals are dependent both upon species' preferences and foods available in the environment. Omnivorous species are found in taxonomic orders that include bats, marsupials, pigs, primates, rodents, and Carnivora. 1,2 However, grouping these species in an omnivorous category tends to obscure the diversity of their dietary habits....

Dietary Sources and Interconversions

Common dietary sources of the various polyunsaturated fatty acids are shown in Table 1. Vertebrate animals can synthesize saturated and monounsaturated fatty acids from dietary carbohydrate but are unable to synthesize 18 2o6 or 18 3o3. These polyunsaturates must, therefore, be provided in the diet and are referred to as essential fatty acids. Animals can, however, convert 18 2o6 to 20 4o6 via the action of desaturase and elongase enzymes. 1 The same enzymes are involved in the conversion of 18...

Dietary Manipulation Of Fatty Acid Profile And Nutrient Content Of Animal Products

Manipulation of the fatty acid profile of body lipid and of vitamin and mineral content in slaughter animals should be considered, as it influences storage and sensory properties of animal products. It also provides a means to supply fatty acids and nutrients in animal products that are beneficial to human health. Fig. 2 Schematic representation of the relationship between energy intake and accretion of body protein and body lipid in growing animals. (From Refs. 3,6,7.) Fig. 2 Schematic...

Other Biological Hazards

Food-producing animals may also serve as sources of parasitic and viral disease agents. 1 For example, swine may be involved in the transmission of trichinosis (Trichinella spiralis), sarcocystosis (Sarcocystis spp.), and toxoplas-mosis (Toxoplasma gondii) and poultry of toxoplasmosis, whereas beef cattle may transmit tapeworms (Taenia spp.) and Sarcocystis spp. or serve as indirect vectors for the transmission of Cryptosporidium parvum (cryptosporidio-sis) through water contaminated with...

Gestational Development and Lactogenesis

Extensive mammary development occurs during gestation, at which time mammary growth is exponential and driven by hormones of pregnancy. 1,2 Epithelial development during pregnancy gives rise to true alveoli that emanate from the distal termini of ducts. The resulting structures have been likened to clusters of grapes, wherein the grapes represent alveoli and the stems represent ducts that drain these secretory units. Alveoli consist of a single layer of epithelial cells overlain and engulfed by...

Response To Stress

Every environment can expose livestock to some type of stressor. These stressors can be thermal, physical, and social. How the animal is able to cope with these potential stressors depends on the species abilities, for instance, swine can not sweat. Similarly, past experiences are important for coping in situations that may involve confrontations between individuals. When livestock are exposed to a stressor, the body automatically initiates a stress response. Stress responses are characterized...

Control And Regulation Of Maternal Behavior

Species-specific maternal behavior appears spontaneously after delivery, even in naive animals. Prior to birth many females are indifferent, or even aggressive, to neonates, but maternal behavior is expressed immediately at the birth of their own young. The rapid onset of maternal care requires hormonal priming by an increase in ovarian hormones (estrogen and progesterone) and Fig. 2 Passive maternal behavior shown by the pig (a) in comparison to the active behaviors shown by sheep (b). Photos...

In Vitro Fertilization

For over two decades researchers have been fine tuning in vitro (test-tube) fertilization (IVF) procedures for cattle. The IVF technology has only been commercially available at embryo transplant stations for cattle producers since the early 1990s because IVF is a complex multi-step process that requires a well-equipped laboratory and a skilled technician. From good-quality oocytes harvested from cattle ovaries, one would expect a 90 in vitro maturation rate and > 80 cleavage rates. The...

Body Weight Management

Body weight management comes into play at two critical periods during the life of a flock of laying hens, specifically the rearing and the molt periods. During the rearing period it is important to manage the nutrition, vaccination, beak trimming, house ventilation, and general management program so that the pullets meet the recommended body weight for the strain. 3 With the modern layer strains this process can be managementintensive, because it is not recommended to feed-restrict Threshold...

Husbandry And The Anticruelty Ethic

For most of human history, the anticruelty ethic and laws expressing it sufficed to encapsulate social concern for animal treatment for one fundamental reason During that period, and today as well, the majority of animals used in society were agricultural, utilized for food, fiber, locomotion, and power. Until the mid-20th century, the key to success in animal agriculture was good husbandry, a word derived from the old Norse term for ''bonded to the household.'' 1 Humans were in a contractual,...

Behavior of Mothers of Altricial Offspring

These species are often predators and frequently solitary, or they live in family groups (e.g., rodents, dogs, cats). Altricial offspring are generally born in large litters, and individuals are small relative to maternal bodyweight. Maternal investment in each individual is, therefore, relatively low, and the survival of some of the litter takes precedence over the survival of all offspring. Mothers of altricial offspring construct a den or nest in which to give birth and maintain the litter...

Mysticeti Baleen Whales

The baleen whales (suborder Mysticeti) are filter-feeders that reach gargantuan size. At 100,000 kg or more, a fully- grown blue whale attains the largest mass of any animal. This large mass allows females to mobilize vast quantities of nutrients from body reserves during lactation. 4,9 Most of the very large species, such as gray, humpback, fin, and blue whales, migrate back and forth between high-latitude polar regions, where they feed, and warm temperate tropical regions, where they give...

Glucose Metabolism

Some of the increase in hepatic gluconeogenesis in late-pregnant ruminants is due to increased voluntary feed intake. 1 However, intake is often constrained by physical factors such as diet quality and abdominal distension, as well as endocrine factors such as the surge in estrogen secretion in late pregnancy. 2 Under these or more controlled conditions of feed restriction, an increase in glucose production is sustained by increased peripheral mobilization and hepatic uptake of endogenous...

Dietary Determinants Of Efficacy

At least four dietary factors can modulate phytase efficacy. First, high levels of dietary calcium or calcium phosphorus ratios reduce the effectiveness of phytase. In phytase-supplemented diets, the recommended calcium phosphorus ratio is 1.2 1, not 2 1 as used in diets with adequate inorganic phosphorus added. Second, moderate to high levels of inorganic phosphorus may inhibit the full function of phytase. Third, supplemental organic acids such as citric acid or lactic acid enhance phytase...

Placental Endocrine Functions

The placenta is a complex endocrine organ that synthesizes and metabolizes a large variety of steroid and peptide hormones as well as numerous other substances in large quantities for release into maternal and fetal circulations. Most of the substances appear to be synthesized by trophoblast elements such as the binucleate cells of sheep. The precise roles of placental and fetal hormones, the mechanisms by which they are involved with placental functions, fetal growth and development, and...

Dietary Supply Of Amino Acids

Bound protein in feedstuffs and pure forms of crystalline AA supply AAs in pig diets. Crystalline AAs are assumed to be completely absorbed from the gut and utilized by the animal. In contrast, animals are only able to utilize a portion of the AAs contained in bound protein for metabolic functions. Therefore, the total amount of AAs in a diet is not equal to the amount of AAs that are available to the animal for metabolic functions. As a consequence, estimates of bioavailability of dietary AAs...

Availability and Transport of Circulating Cholesterol

Free cholesterol is the precursor for all steroid hormones, but free cholesterol is typically not found within ste-roidogenic cells. Cholesterol transport involves protein protein interactions and is critical for steroid biosynthesis. Most of the cholesterol is provided by low-density lipoproteins (LDL) or high-density lipoproteins (HDL), although small amounts of cholesterol are produced by de novo synthesis. The LDL HDL cholesterol complexes bind to specific membrane receptors and are...

Rationale For Xenotransplantation

Xenotransplantation has been viewed as a plentiful source of organs and tissues for transplantation (Table 1). 1,2 However, xenotransplantation may even be preferred over allotransplantation in certain circumstances. Where organ failure is caused by a viral infection, e.g., hepatitis, xenotransplantation might be preferred because the transplant would resist reinfection by the virus that caused organ failure. 3 Xenotransplantation might also be preferred as a way of delivering genes of...

Muscle Metabolism

Muscle tissue is specialized for movement in humans and animals. The compound adenosine triphosphate (ATP) contains high-energy phosphate bonds, and these bonds can be broken to convert chemical energy into work by the myofibrils. Muscle contraction occurs when a nerve signal causes the depolarization of the muscle cell membrane and the release of calcium from the sarcoplasmic reticulum to activate the myofibril contractile proteins. Adenosine triphosphate is required to power the contraction...

Glandular Extracts Hormones And Enzymes

Glandular extracts, hormones, and enzyme collections are specific to the species, age, and sex of respective animals. Major products such as pepsin, rennin and other digestive enzymes, lipase and trypsin enzymes extracted from the pancreas, bile from the liver, adrenocortical steroids from the adrenal glands, and female reproductive hormones from the ovary are all medically significant products. Though insulin has been referenced as one of the prime pharmaceutical products derived from animal...

Effects Of Colostral Immunoglobulins And Antiinfectious Agents

The immune defense is immature in newborn animals, which depend on passive immunization from their mothers. Transmission of passive immunity from mother to young varies among different species (Table 3). In certain species (e.g., primates and rabbits) passive immunity is passed from the mother to the young through the placenta before birth. However, in most farm-animal species (e.g., cattle, sheep, pig, and horse), the newborn depends on the intestinal transmission of colostral immunoglobulins...

Behavior of Mothers of Precocial Offspring

These species are generally grazing prey animals and live in large social groups of several females with a male (e.g., horse) or matrilineal groups (e.g., sheep). Litters comprise one or two large (relative to the maternal body weight), well-developed, and mobile young. A specific birth site may be selected, sometimes remote from the social group, but nest building does not occur. Behaviors immediately following birth are usually directed toward recognition of their individual offspring and...

Partition of Maternal Nutrient Supply Between Maternal and Conceptus Tissues

The progressive gestational increases in fetal and placental demand for nutrients results in the consumption Fig. 1 Schematic representation of the pregnant ewe and its conceptus, illustrating the approach to estimating the partition of nutrients in vivo. Fig. 1 Schematic representation of the pregnant ewe and its conceptus, illustrating the approach to estimating the partition of nutrients in vivo. soon after birth and is characterized by very high plasma concentrations of growth hormone and...

Pasture Resource Availability

The number of pastures and their relative sizes can have a major influence on which crossbreeding systems are feasible. Some very effective crossbreeding systems, such as multibreed composites, can be conducted in a single breeding pasture. These systems allow relatively efficient use of heterosis, but do not allow as much opportunity to exploit breed differences as when multiple breeding pastures are available. In most cases, using a terminal sire breed will require one breeding pasture that...

Colostrum Composition

The initiation of mammary secretion (lactogenesis) consists of two stages. 1 The first stage takes place before birth and is characterized by accumulation of yellow, viscous, serumlike colostrum in the mammary glands. The second stage of lactogenesis takes place at or shortly after birth and is characterized by active synthesis of lactose in the mammary glands. Different secretory mechanisms of colostrum and milk are reflected in their chemical compositions (Tables 1 and 2). Although wide...

Sperm Mediated Gene Transfer

The simplest, but most controversial, method of gene transfer involves merely mixing a transgene with spermatozoa and using them to fertilize oocytes, either in vitro or by artificial insemination. The use of sperm-mediated transfer in mice by Dr. Lavitrano 8 was initially discounted as unrepeatable by many investigators. During the past decade, research on this procedure has persisted and many investigators report successful gene transfers by this technique. Unfortunately, only a few studies...

Transcriptional Control Of Cell Differentiation

Studies have shown that both internal and external factors can regulate differentiation by mediating gene and protein expression. External compounds, such as growth factors, pharmaceutical agents, lipids, hormones, etc., influence cell differentiation through cascades that culminate in transcription factor activation followed by gene transcription. 2 This may be followed by translation of the gene product into a protein that induces the cell's phenotypic change. For example, thiazolidinediones...

Stress And Muscle Metabolism

Preslaughter stress in animals causes release of catecholamines and depletion of muscle glycogen, which influence the extent of postmortem glycolysis and pH decline in muscles. Severe stress in goats prior to harvesting may result in inferior meat quality. Short-term preslaughter stress causes reduction in muscle glycogen levels in young goats, but not in older ones (Fig. 3), although increases in circulating cortisol and glucose concentrations are noticeably less in young goats compared to...

Ewe Reproduction

The ratio of light to dark during a day and the absolute periods of light and dark are known to influence reproduction in many species, especially the seasonal breeders. 4 Ewes differ from cattle in that they are anestrous, which means very few come into heat (estrus) between May and July. The decrease in the light-to-dark ratio triggers hormonal change which result in ewes exhibiting estrous cycles. The two months when most ewes show estrus are October and November (temperate zone), and the...

Well Being Assessment Concepts and Definitions

Texas Tech University, Lubbock, Texas, U.S.A. Animal welfare and animal well-being are more or less interchangeable terms. Assessment of animal welfare seems to include some subjective assessments, while the term animal well-being is viewed as more objective in some circles. In practice, the two terms have very similar meaning to the public and most scientists. Animal welfare well-being assessment is often criticized by scientists as being anthropomorphic. Anthropomorphism is the ascribing of...

Skeletal Muscle Growth

Postnatal skeletal muscle growth coincides with rapid body growth, and requires both DNA and protein accumu- Fig. 2 Accretion of bone, muscle, and fat during postnatal live weight gain of cattle. Intramuscular Intermuscular Subcutaneous Fig. 3 Distribution of fat in various depots of pigs, sheep, and cattle. Intramuscular Intermuscular Subcutaneous Fig. 3 Distribution of fat in various depots of pigs, sheep, and cattle. As adipogenesis proceeds, the lobules give rise to large lobes of...

Environment and Nutrition

In some species, it may be economically feasible to modify the temperature, humidity, air flow, photoperiod, etc. to provide a more favorable environment for optimal animal growth. At less-than-optimal temperatures, energy is expended to maintain body temperature, whereas at elevated temperatures, animals decrease feed intake to diminish heat production. Both extremes produce less-than-optimal growth. Shelters of various design and even enclosed buildings may be economically advantageous in...

Advantages Of Markerassisted Selection

Traditional methods of selection can produce very accurate evaluations of genetic merit for traits that are high in heritability (observed or measured value is a good predictor of breeding value) or for individuals that have many progeny with phenotypes recorded. However, many traits of economic importance in livestock are low or moderate (10 40 ) in heritability or can only be measured postmortem, in which case, accurate genetic evaluations are only possible through progeny testing. Other...

Utilization Of Sexsorted Sperm

The first sex-selected mammalian offspring were rabbits born following surgical insemination of sexed sperm. 5 Later, in a milestone achievement, a similar system was used to produce sex-selected piglets, demonstrating the utility of the system for pre-selecting the sex of offspring in domestic livestock. 6 The first calves born were from embryos derived from IVF with sex-sorted sperm, but most of the recent work in cattle has been done using

Cortisol and CRH Expression

Cortisol is secreted under diverse conditions that impact both physiology and behavior. 3 Short-term cortisol release is protective and facilitates normal physiological and behavioral adaptive processes, whereas high levels of cortisol have detrimental effects on various regulatory processes such as immune and neuroendocrine systems. The behavioral and physiological effects of CRH and cortisol are often independent of one another however, cortisol can influence CRH neurons by inhibiting and...

Well Being and Handling

Colorado State University, Fort Collins, Colorado, U.S.A. Reducing stress during handling for procedures such as vaccinations, milking, and herding will improve both animal welfare and productivity. Pigs and dairy cows that are afraid of people have reduced productivity. Pigs have lower weight gains and fewer piglets and dairy cows produce less milk. Fearfulness was assessed by measuring the animal's willingness to approach people. Cows on dairies where the employees had received training in...

Competitive Exclusion

Competitive exclusion (CE) is the prophylactic treatment of young animals with suspensions of enteric bacteria obtained from healthy adults. It is a highly effective method of controlling gut colonization by Salmonella and other enteric pathogens, particularly when cultures are administered to animals shortly after birth while the ecology of the gastrointestinal (GI) tract is relatively naive. 1 The mechanism by which CE cultures confer protection is not clearly understood but may involve one...

Utilization Of The Frozen Germplasm

Stored genetic resources should be used on a regular and systematic basis, and not considered a frozen museum archive. The strategies for maintaining genetic diversity should be managed by a governing body, as exemplified by the Conservation Breeding Specialist Group of the International Union for Conservation of Nature and Natural Resources, now known as IUCN-The World Conservation Union. 7 In Great Britain, the Heritage Genebank Project, managed by The Sheep Trust, 8 was established during...

Oocyte Collection From Donor Females

The IVF procedure offers an alternative to producers who have genetically valuable cows that for some reason are unable to produce viable embryos through standard embryo collection procedures. This technology can be used with oocytes harvested from older nonovulating cows, females with physical injuries (e.g., lameness), and problem breeding cows (e.g., abnormal cervix). Good success has been reported using IVF procedures on supplemental oocytes harvested from cows with cystic ovarian disease....

Pantothenic Acid

Pantothenic acid was discovered as the cure for chick pellagra. Pantothenic acid deficiencies have been reported only as a result of feeding semisynthetic diets or an antagonist to the vitamin. 2 Pantothenic acid is the compound also known as pantoyl-beta-alanine. 1 Pantothenic acid is found in feedstuffs in the form of coenzyme A (CoA), acyl CoA synthetase, and acyl carrier protein. CoA is hydrolyzed in the intestinal lumen to pantothenic acid. Pantothenic acid crosses the intestinal lumen...

Follicular Growth During the Luteal Phase

Early stages of ovarian follicular development are not dependent upon gonadotropins a pulse of follicle stimulating hormone (FSH) initiates growth of a cohort of tertiary follicles 4,5 and is required for growth from approximately a diameter (mm) of 2 to 4 (ewe) or 4 to 9 (cow). Frequent pulses of LH are necessary for development beyond about 4 or 9 mm, respectively. As follicles grow, they secrete increasing amounts of estradiol-17p and inhibin. Each hormone has negative feedback effects upon...

Farm Animal Welfare Economic Policies

Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, U.S.A. Animal welfare is intricately related to economics. The various animal production systems (beef, pork, poultry, cheese, etc.) compete within and with each other for the same consumer dollar. This tends to keep production costs and food prices at a minimum. Technology has replaced labor and driven systems toward animal confinement and larger production sizes. And the public is increasingly asking for...

Amino Acid Degradation

Microorganisms in the digestive tract degrade all amino acids, with ammonia, fatty acids (including branched-chain fatty acids, acetate, propionate and butyrate), H2S, and CO2 being major products. In animals, amino acids are catabolized by cell- and tissue-specific pathways. The liver is the principal organ for the catabolism of all amino acids except for BCAA and glutamine. There is growing recognition that the mammalian small intestine extensively degrades essential and nonessential amino...

Broodfish and hatchery management

Proper management and care of broodfish are critical for high reproductive or spawning success. Many factors such as water quality, stocking density, and management outside the spawning season can affect catfish reproduction. Spawning success can be as high as 20 to 30 in two-year-old fish, but best reproduction is obtained from three- and four-year-old fish. The industry average for spawning success is estimated to be around 30 to 40 , and for egg hatching around 60 . A sex ratio of 1 1 or 2 1...

Handling Bulls And Boars

Research has shown that bull calves reared in physical isolation from their own species are more likely to be aggressive and dangerous after they mature than bull calves reared on a cow in a herd. 10 Dairies have learned from experience that bucket-fed Holstein bull calves can be made safer by rearing them in group pens after they reach six weeks of age. Young male calves must learn at a young age that they are cattle. If they grow up without social interactions with their own species, they may...

Well Being Assessment Behavioral Indicators

Kansas State University, Manhattan, Kansas, U.S.A. Animal well-being can be characterized as the harmony an animal is experiencing mentally and physically with its environment. Animal well-being is often used interchangeably with the term animal welfare. Domestic livestock and poultry are raised under a variety of environmental conditions that are vastly different from those of their wild ancestors. The scientific assessment of the well-being of livestock and poultry has become important to the...

Milk Synthesis

Virginia Polytechnic Institute and State University, Blacksburg, Virginia, U.S.A. Copious milk secretion begins shortly after parturition and requires 1) the prepartum proliferation of alveolar epithelial cells 2) biochemical and structural differentiation of these cells and 3) synthesis and secretion of milk constituents. Except for bottle-fed humans and milk replacer-fed dairy calves, the success of reproduction does not end with the birth of healthy offspring. Rather, suckling of the neonate...

Milk Yield Differences

Cornell University, Ithaca, New York, U.S.A. Milk production is an integral component of the total life cycle of mammals. The term lactation is another term commonly used to describe this biological process. Milk production serves a number of functions. A primary function, in most species, is to provide nutrients for newborn animals. The milk produced in the first few days of lactation is called colostrum. Typically, colostrum contains a higher level of protein, fat, energy, and solids than...

Milk Composition Species Comparisons

Smithsonian Institution, Washington, D.C., U.S.A. All mammals depend on milk as their primary source of nutrients during a phase of development. This may begin at an early developmental stage and cover a long period, as in hatchling monotremes or neonatal marsupials, or it may be a brief period following the birth of large, precocial offspring. Milk composition can change markedly during lactation, especially in monotremes and marsupials. These changes probably correlate to developmental...

Most Commonly Cultured Species

Atlantic salmon (Salmo salar) is one of the most-produced fish in the global aquaculture industry, with Norway and Chile being two of the largest producers. In 1980, only 10,000 tonnes were produced globally, but by 2010 it is expected that over 2 million tonnes will be produced. 1 Marine net pens are the most commonly used culture system, and production reached 1.4 million tonnes in 2002. Bighead carp (Aristichthys nobilis) are native to the lowland rivers of China and feed principally on...

Minor Fish Species

Arctic char (Salvelinus alpinus) has the most northern distribution of any freshwater fish species and is common in the Arctic and subarctic regions of North America, Europe, and Asia. It is a relatively new aquaculture species that, as yet, does not have much production. However, it is easy to culture, has wide consumer acceptance, and should return a fairly high price to producers. Asian sea bass (Lates calcarifer), also known as baramundi, is a carnivorous fish that spends its first 2 3...

Factors Involved In Choosing A Crossbreeding System

There are nine factors to consider in helping identify a feasible crossbreeding system. Those factors are 1) relative merit of breeds available 2) market endpoint for the calves produced 3) pasture resources available 4) size of the herd 5) availability of labor at calving time 6) availability of labor just before the breeding season 7) method of obtaining replacements 8) system of Fig. 1 Profit from breeding systems at weaning and har vest endpoints. Fig. 1 Profit from breeding systems at...

The Pig As A Model Of Omnivorous Mammals

The eating habits of the domestic pig closely resemble those of the human, with respect to both what it eats and the pattern of meals. In young pigs, the pattern of eating consists of periodic meals separated by intermeal intervals of a few hours' duration. Much of the water consumed is drunk in close association with meals. It is presumed that during the intermeal intervals deficits of nutrients slowly develop as they are consumed in body metabolism. These deficits are then corrected at...

Welfare Issues

Intensive turkey production does not account for many of the birds' psychological and physiological needs, resulting in welfare concerns. Turkey chicks are precocial and are sustained by yolk reserves until 3 days of age. Learning to eat and drink appropriately during this time is essential, and it is common for a proportion of chicks to die (starve-out) from failing to learn, hence the use of brooding pens. Chicks' attention can be directed by tapping on the feeders and drinkers, thus...

Transmissible Spongiform Encephalopathies Biology and Disease

National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, Iowa, U.S.A. Prions are proteinaceous infectious particles, and in the most general of terminology they are chromosomally encoded proteins that have undergone a conformational change such that the new altered conformation is capable of causing a conformational change in additional molecules of the normal prion protein. They are the causative agents of a class of progressive and...

Sperm Capacitation

Department of Animal Science, University of California Davis, Davis, California, U.S.A. Abstract Sperm capacitation is a membrane destabilization process that allows membrane fusion to occur prior to and during mammalian fertilization. Removal of seminal plasma coating proteins from sperm is characteristic of capacitation in ejaculated sperm hence ejaculated sperm typically capacitate more slowly than epididymal sperm. Increased exposure to bicarbonate leading to elevated cyclic AMP, activation...

Growth and Development Peri Implantation Embryo

Progesterone Ruminant

Department of Animal Science and Center for Animal Biotechnology and Genomics, Texas A& M University, College Station, Texas, U.S.A. Veterinary Integrative Biosciences and Center for Animal Biotechnology and Genomics, Texas A& M University, College Station, Texas, U.S.A. Department of Animal Science and Center for Animal Biotechnology and Genomics, Texas A& M University, College Station, Texas, U.S.A. Guillomot et al. 1 indicated that the phases of implantation in mammals include 1)...

General Division Of Foods Feeds Or Ingredients

Food or feed is the source of materials that an animal's body needs to grow or to replace what it is using each day. In order to gain some information about what is in a feed or an ingredient, a procedure is followed that separates all feeds into six different parts or fractions. These are moisture or water, crude protein, crude fat, crude fiber, ash or mineral, and nitrogen-free extract. Results of some of these analyses are found on feed tags or food labels. All of these fractions are...

Greenhouse Gas Emissions from Animal Production Systems

Department of Animal Sciences, Colorado State University, Fort Collins, Colorado, U.S.A. Kristen A. Johnson Department of Animal Sciences, Washington State University, Pullman, Washington, U.S.A. The burning of fossil fuels and allied human activities of recent centuries result in increasing concentrations of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in the earth's atmosphere. These major gases and other miscellaneous gases and particles act like a greenhouse, blocking...

Growth and Development Pre Implantation Embryo

Stage Blastocyst Pig

Department of Animal Science and Center for Animal Biotechnology and Genomics, Texas A& M University, Texas, U.S.A. Veterinary Integrative Biosciences and Center for Animal Biotechnology and Genomics, Texas A& M University, Texas, U.S.A. Department of Animal Science and Center for Animal Biotechnology and Genomics, Texas A& M University, Texas, U.S.A. In most species, ovulated ova are at Metaphase II of meiosis and remain so until fertilized within the oviduct some 5 30min after...

Placental Transfer

Essentially all maternal fetal transfer occurs via the placenta. The chorioallantoic placenta has the same transfer mechanisms found in other epithelial systems. These include passive diffusion, facilitated diffusion, active transfer, and receptor-mediated endocytosis. Most substances present in fetal or maternal blood can cross the placenta via one or more of these mechanisms. Numerous substances traverse the placenta by simple diffusion. In general, diffusion permeability varies directly with...

Conclusion Utility Of Acquired Immune Responses

Acquired immune responses ultimately determine whether an infectious organism will be controlled and disease prevented.1-3'6-1 Vaccines enhance immunity by altering the acquired immune response. Much research is now aimed at biotherapeutics that alter the balance between Th1 and Th2 cytokine responses. Because cytokines set the direction and amplify the intensity of specific antipath-ogen and vaccine immune responses' setting the direction of the early specific acquired immune response will...

An Animals Own Performance

Animals were originally selected on the basis of their own phenotype. That is, cows that give the most milk, sows that have the largest litters, hens that lay the most eggs, and horses that run the fastest are examples of this type of selection. Although selection on phenotypes is very easy to apply, the accuracy of phenotypes as an estimate of genetic merit is equal to the square root of heritability. Heritability is the proportion of the variability in a trait that is attributable to genetics...

Manure As A Fertilizer For Crop Production

In the United States, animal agriculture accounts for approximately 100 billion annually, or half of all farm sales. The manure produced by dairy and beef cattle, poultry, and swine contains vast amounts of nitrogen and phosphorus (Table 1) that in some regions can be landapplied at agronomic rates on farms where it is produced.1-2-1 Nitrogen (N) is the most limiting nutrient to cereal crop production, so the fertilizer value of manure is usually equated to its ability to provide N to a...