- In 2001, Norway and Chile produced 43% and 25% of the Atlantic salmon, respectively. - Atlantic salmon make up the greatest part of the world production of the various salmon species T in 2001. - Of the Pacific salmon species, the production of coho salmon (Oncorhynchus. - [2] Feed (including pigments, vitamins, medication, and feed transport) accounted for 51% of the production costs in Norway and 61% in Chile. - Proceedings of the Seminar of the CIHEAM Network on Technology of Aquaculture in the Mediterra nean (TECAM), Zaragoza, Spain, 1997. - Proceedings of the EMBO Workshop on Reproduction &. - Other important traits can only be measured late in the productive life of the individual. - DNA tests are currently only available for a few of the genes with moderate or large effect. - The aggregate effect of the remaining genes is referred to as the residual polygenic breeding value, [4]. - which will often account for a very substantial proportion of the genetic variance for a trait. - As more data is acquired, estimates of the effects of test genotypes will improve. - Proceedings of the 7th World Congress on Genetics Applied to Livestock Production, Montpellier, France, Aug . - Only animals that reproduce influence the genetic composition of the next generation. - Heritability is the proportion of the variability in a trait that is attributable to genetics (Table 2). - Future selection programs will be improved versions of the traditional selection methods. - Currently, the role of sheep enterprises in much of the world is the production of lamb meat. - Yet benefits from crossbreeding depend on the genetic merit of the pure breeds crossed. - Where output is ample, the quality of the carcass becomes a focus. - Regardless of the strategy followed, an optimum rather than maximum number of lambs born is the goal. - Sheep are one of the most common species of livestock in the world and were the first to be domesticated. - Sheep inhabit many parts of the world from the deserts of Africa to the high mountains of South America. - Each factor must be considered in order to achieve opti- mum production and health of the animals. - In many parts of the world, sheep have adapted to the local environment over years of natural selection. - In the arid parts of the world, the only feed source may be coarse bunch grasses, shrubs, and woody plants. - This can be ascertained by a thorough health examination, serological testing, and health records of the flock of origin. - Ovine progressive pneumonia (OPP) is a more subtle disease with no apparent clinical signs early in the course of the disease. - Scrapie is a degenerative disease of the nervous system. - In most sheep-producing areas of the world, energy is the nutrient most likely to be limited in the diet. - Only by feeling under the wool can the condition of the animal be determined. - Sheep derive most of the protein by digesting the micro- organisms that leave their rumen. - Minerals play a major role in skeletal and nervous system functions of the body. - The health of the newborn is dependent upon the health and nutritional status of the dam. - The majority of the sheep milk is used to produce either yogurt or various varieties of cheese.. - With the higher fat in sheep yogurt, the potential harshness of the lactic acid in the yogurt may also be lessened. - In the United States, most of the sheep milk cheeses produced are artisinal cheeses. - Sheep milk yogurt and cheese are major dairy products in many of the European and Asian countries. - [2] The short-chain fatty acids contribute many of the distinctive flavors observed in sheep milk and sheep milk products. - [4] In the postwean period of the lactation, fat content is comparable for all management systems.. - Typical distribution of the various nitrogen fractions in sheep, cow, and goat milk are shown in Table 2.. - Most of the calcium in sheep milk (75 88%) is in the colloidal phase as compared to only 62 76% in cow milk. - Flavor and functional characteristics of sheep milk products may vary widely due to the seasonal nature of the milk supply.. - impaired rennet coagulation rates or lack of firmness of the gel. - Table 2 Average distribution of the various nitrogen fractions in milk. - Variations of the Major Nitrogen Fractions of Goat and Ewe Milk. - In most of the world’s sheep-grazing systems, the main period of pasture growth is in spring/. - ha) to the point that for some of the year at least, the intake of individual sheep is constrained. - These general rules are strongly influenced by the physiological state of the animal. - Below 50% digestibility, weight loss is likely, regardless of the amount of pasture on offer.. - In most cases, the protein content of green pasture is in the range 15 25% and probably provides soluble protein in substantial excess relative to the requirements of the rumen. - The legume (clover) content of pasture can exert a profound effect on the nutritional status of the grazing sheep. - because of the faster rate of legume particle breakdown in the rumen. - The products of the digestion of legumes are also used with greater efficiency for growth. - [3] The degree of this substitution may even be enough to negate the effects of the supplement.. - It follows that sensible nutritional management of the sheep must include a program for the control of internal parasites.. - A scrotal circumference measurement is taken, along with palpation of the testicles. - Photope- riod regulates the reproductive cycle of the ewe and the effects are most dramatic in the more temperate-type geographic zones. - For the ewe, it is primarily the diet that affects ovulation and lambing rates and the survival of the newborn lamb.. - As a result of the reduction in fat deposition, there is a corresponding reduction in feed intake. - As a consequence of the increased protein mass and protein synthesis, there is also an increase in maintenance requirement. - Hormones of the anterior hypophysis. - The effect of the injection of hypophyseal extract in advanced lactation. - ORGANIZATION OF THE SEMINIFEROUS TUBULE. - Spermatogenesis occurs within the seminiferous tubules of the testes (Figs. - The acrosome contains enzymes that aid in sperm penetration of the egg during fertilization. - Basic aspects of neuroendocrine regulation of the hypothalamic pituitary gonadal axis are well established in the male. - Briefly, a differentiating group of spermatogonia in the basal compartment begins spermatocytogenesis within a short section of the seminiferous tubule. - 1 Organization of the mammalian testis and excurrent ducts. - The exquisite timing of the cycle is intrinsically con- trolled and always the same within a species. - Anatomically, the epididymis is a discrete organ attached to the side of the testis and characterized by caput (head), corpus (body), and cauda (tail) regions. - 2 Cytology of the bull testis. - Endocrinology of the Male and Spermatogen esis. - Despite ex- tensive research efforts in the past 50 years, superovula- tion remains one of the weakest links in ET technology;. - size follicles is limited to the follicular phase of the cycle.. - Cattle and buffalo FSH administered on days 8 12 of the estrous cycle. - In the mare, where application of the conventional ET technique is impeded by the lack of a suitable superovulation treatment, active immunization has been shown to increase superovulation. - Superovulation can be induced in the gilt and sow by administering a single dose of PMSG at the start of the follicular phase of the estrous cycle. - In Proceedings of the 18th Meeting European Embryo Transfer Association (Rolduc). - An example of the importance of caretaker skills can be seen at the time of handling.. - Pure-breeding, as we define it now, started in Britain in the second half of the 18th century. - A common practice is to use profit equations of the form:. - This procedure has been illustrated in the elimination of the deleterious halothane gene from maternal lines, achieved in the 1980s by using biochem- ical markers. - on the order of 0.5 1.5% of the mean annually. - In The Genetics of the Pig. - Genetic Improvement of the Pig. - The Genetics of the Pig;. - 5) competency of the stockpeople. - In several parts of the world, legislation regarding stocking density, as in the European. - The ability to clinically examine, recognize, and treat disease in pigs is the responsibility of the entire farm. - Adequate training of stockpeople in the recognition of disease is a responsibility of the farm’s attending veterinarian. - Modern pig farming has a greater reliance on employed help, who may have little interest in the well-being of the pig. - In addition to swine health, feed wastage plays a key role in the profitability of swine farms, yet farms may casually waste 10% of the feed. - Analysis of the floor would also include hygiene. - Failure of the ventilation system is the classic reason for respiratory disease. - Preweaning diarrhea is often associated with drafts and chilling of the neonatal piglet.. - Direct marketing sales of pigs directly to slaughterers was a small minority of the total marketing. - The pegboard section of the retail meat department holds the further- processed products. - This change has come about only because of a concerted commitment on the part of the U.S. - The deficiency probably is part of the farm’s standard operating procedures. - In both systems, the high flow volume and the slight slope of the waste-receiving pit under the pens (1 1.5%. - Occasionally hydraulic loading rate of the application field is a limitation.
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