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Economics Given the strong demand for muskox products and the limited supply of animals, there is potential for the muskox industry in Alaska. Business success will depend on calf survival (>70-80%), herd management (eg. herd size and harvest), and the reliable supply of forages (grass hay and/or pasture) and formulated feeds. This is no different than the parameters for succeeding in other diversified animal enterprises. Budgets and revenue scenarios indicate that a new muskox enterprise with limited animal numbers is feasible. The feasibility will increase if this type of enterprise is an add-on or a change in an established agricultural business. The land and buildings, and in the case of livestock operators, the infrastructure, may already be in place. The modest investment may encourage retirees to enter the industry. It may also be an attraction to those who have established employment and are looking to an enterprise for other members of their family. The restriction to development of multiple enterprises of this type will be the supply of animals from captive herds in Canada and Alaska. Tested supplemental rations and calf diets are available from an Alaskan manufacturer (Alaska Pet and Garden, Anchorage) under license agreement with University of Alaska Fairbanks. Long term management of pastures and a reliable supply of grass hay will become increasingly important as herds develop to the capacity of each facility.
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food intake and growth From ASTF Final Report, April 2003 -- Feeds for qiviut production: trace mineral nutrition of muskoxen. The amount and quality of forage is critical to management of muskoxen because grass hay provides 97% of the dry matter ingested by adults. Demands for hay increase in late summer when food intakes increase by 74% in castrated males between April and August in Fairbanks. The efficiency of digesting fiber is sustained at high intakes indicating a remarkable plasticity of ruminal function. High intakes at high efficiencies late in the summer support rapid fat gains. This seasonal adjustment in nutrient uptake would allow reproductive females to rapidly replenish tissues that were depleted during milk production and gain fat reserves before winter. High food intakes also permit muskoxen to load nutrients such as copper and zinc that are only present at low concentrations in the diet. Grass hay is typically low in sodium but high in potassium. Therefore, high forage intakes are associated with excess intakes of potassium that exacerbate the low levels of dietary sodium. Supplements provide 78% of dietary sodium for captive muskoxen and probably facilitate high food intakes and body mass gains by compensating for the large urinary loss of electrolytes during autumn. Seasonal growth of lean tissues and hair (qiviut) alter demands for nutrients in muskoxen. Young muskoxen mostly gain lean tissues such as muscle and bone during the first summer and autumn. Consequently, young muskoxen are only 5% body fat in the middle of winter but soon gain both lean and fat tissues during the second summer to reach adult fat contents of approximately 20% body mass before the second winter. Low stores of subcutaneous fat could make young muskoxen more vulnerable to thermal stress especially if wet conditions reduce the insulative capacity of their coats during the first winter. Males grow more rapidly than females during the second year probably in response to testosterone production. Rapid growth of males will probably increase their food intakes when compared with females in the second year. Captive females are often able to complete gestation in the second winter because adequate reserves of lean and fat tissues are deposited during the second summer. Breeding of these young females may however, curtail further growth and impair delivery of large calves. Supplemental protein above the concentration of grass hay (10% crude protein in dry matter) does not increase hair growth or lean gains in young muskoxen. The excess protein is probably deposited as fat after eliminating the excess nitrogen. Therefore sustaining high intakes of hay with 10% protein is probably adequate for non-reproductive animals as long as supplements are provided to maintain supplies of minerals such as sulfur, sodium, copper and zinc. Protein supplements of 14% crude protein (dry matter basis) may be useful for lactating females to maintain sulfur and nitrogen supplies when deposition of hair, milk and tissues coincide in late summer. Trace mineral
status Adults Accumulation of copper in adult females probably relies on high intakes of forage during autumn. Castrated males consume a diet of less than 5 ppm copper when grass hay (2ppm copper) and supplement (15 ppm copper) are combined. Liver copper reserves are used to support growth of the fetus and accumulation of copper in the fetal liver. Although demands for energy and protein are both high during milk production, the deposition of copper in milk is low at only 2 to 3 ppm in dry matter. Supplementation of females with injectable copper does not affect the concentration of copper in their calves or in their milk. Calves Weaning is possible at 100 days of age when mothers are placed in breeding harems with bulls. Calves accompanying their mothers may be stressed by the herd activity. Wet conditions from rain and poorly drained pens may also contribute additional stress by increasing the rate of infection from pathogens in the ground. An increased frequency of diarrhea during August can occur with or without separating calves from their mothers at 100d. Recurrent bouts of diarrhea are probably associated with repeated intestinal infections that ultimately slow growth and progressively debilitate the calf. Prolonged debilitation could weaken the immune system resulting in atrophy of lymph glands in the intestine and mesentery. Copper is used for several reactions in the immune response. Copper demands of muskox calves are probably increased by high rates of exposure to pathogens. Captive calves in Fairbanks suffer slowed growth and high rates of diarrhea when provided complete diets of 5 ppm copper without injectable supplements. That is, dietary copper concentrations that are similar to sedges and grass hays are not adequate for these captive animals. Injections of copper-gluconate to supplement this diet reduced frequency of diarrhea and increased the concentration of liver copper when compared with untreated calves (153 vs. 20 µg/g wet mass). The problem of inadequate copper supply to calves is confounded by the transition of the digestive tract and the liver from a diet of milk to forage. Furthermore, calves may be more susceptible than adults to other factors such as fungal toxins in hay. Therefore signs of intestinal infection, poor growth, muscle wasting and low liver copper can be the result of more than one condition. Provision of approximately 9 ppm copper to muskox calves did not prevent the onset of these signs even though this dietary concentration is apparently adequate for development of reindeer and caribou reared at high animal densities in the same facility. Our comparison of muskoxen and reindeer born in captivity indicate that the digestive tract and the liver of reindeer are more developed at birth and that reindeer mature more quickly than muskoxen. Therefore slow development may make muskoxen more susceptible to digestive disruption than reindeer even though both species are born at the same time of year. A complete diet of 30 ppm copper (dry basis) provided from birth to 160 days of age was associated with serum concentrations of 1.7 µg copper/mL and 59 IU ceruloplasmin/mL after 100 d of age. These levels are considerably higher than the minima associated with exhaustion of liver copper in adults. This suggest that the diet was apparently adequate to sustain copper supply even though the animals ultimately succumbed to repeated bouts of intestinal infection and wasting. High dietary concentrations of copper may be essential to rearing captive muskoxen especially when the rate of infection is high and commensurate with the density of animals. Long term management of a captive herd may therefore require restriction of calving areas to pastures that are actively managed to minimize infection rate by limiting animal numbers, rotation of livestock and tilling the substrate. Feeding
standards Formulated feeds for muskoxen are available from Alaska Pet and Garden, Anchorage under license agreement with the University of Alaska Fairbanks. Young muskoxen are provided a complete ration with the typical composition listed in Table 1. This product is designed to be fed free choice from birth to approximately 180 days of age when animals should be transitioned to a diet of grass hay with supplemental rations. The calf ration and the supplements should not be fed free choice because the concentrations of trace minerals are high and designed to augment the low levels in hay. Consequently, free choice feeding of these products could precipitate toxic accumulations of trace nutrients. The products are not designed for multi-species feeding, for example, the high concentrations of copper may be toxic to sheep. Weekly rates of supplementation for muskoxen are 70 g/kg0.75 body weight for yearlings and 35 g/kg0.75 body weight for adults. These weekly rates are plotted against body mass of the animal in Figure 1. The weekly ration should be provided in 2 or 3 equal allotments during the week to provide an even rate of nutrient supply and to minimize rejection, wastage or over supplementation of some animals in the herd. Supplements can be changed to low protein formulations in winter to reduce costs of feed. The largest component of feed intake is grass hay. Predicted intakes of hay are based on the difference between the rate of supplementation and the daily dry matter intakes: 45 g/kg0.75 body mass in winter and 78 g/kg0.75 body mass in summer. Hay intakes are plotted in Figure 2. Those intakes may be reduced considerably by consumption of fresh forages. Table 1. Typical composition of dry matter in the calf ration, supplements and grass hay provided to captive muskoxen at the Institute of Arctic Biology, University of Alaska Fairbanks.
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Muskox calving protocols,
rev. April 2007 Pregnant muskoxen vaccinated with Calf-Guard® (Rota-coronavirus vaccine; E. coli bacterin)
Pregnant muskoxen moved to clean calving pen. Pregnant caribou and reindeer moved to a pasture or pens that have not had recent heavy use.
Check Annual Calving Management Plan Information Sheets posted in Handling Facility for special instructions and information for current calving year. Calving pens / pastures checked early AM, late PM and throughout the day during calving season.
Neonatal handling procedure – See Table 1.
Calves checked throughout the day, in particular watching for:
Treatment for muskox calves with symptoms listed above must begin immediately. See Table 2.
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