. Veterinary studies for agricultural students. Veterinary medicine. LECTURE XXX STOMACH WORMS (SHEEP) The stomach worm is an especially common and serious para- site of sheep, and this means much, for parasitic diseases of sheep are the serious ones. This parasite is very widespread especially in permanent grass pastures. It affects sheep of all ages and young cattle, but especially lambs. Older sheep showing no symp- toms are the ones usually to blame for spreading the disease. The parasite (Hcemonchivs contor- tus) which causes this trouble is a small, threadlike worm, perhaps an inch in le
. Veterinary studies for agricultural students. Veterinary medicine. LECTURE XXX STOMACH WORMS (SHEEP) The stomach worm is an especially common and serious para- site of sheep, and this means much, for parasitic diseases of sheep are the serious ones. This parasite is very widespread especially in permanent grass pastures. It affects sheep of all ages and young cattle, but especially lambs. Older sheep showing no symp- toms are the ones usually to blame for spreading the disease. The parasite (Hcemonchivs contor- tus) which causes this trouble is a small, threadlike worm, perhaps an inch in length and so slender that it must be looked for carefully or one is liable to miss it. The individual worms are somewhat twisted and are found in the fourth stomach. Fre- quently they are in motion. If they are present in great numbers, the stomach contents near the mucous membrane may seem to be fairly alive and squirming. The worms vary from reddish to dirty white in color. Life history.—This parasite is pres- ent in the stomach at all times of the. Ere. 51. year. Embryo of Swmonclius contorius coiled on tip of grass blade. Enlarged 100 times. (Eansom, B. A. I., Circular 93.) The eggs are passed off in the feces, hatch in 14 to 24 hours in warm weather, and reach the ensheathed embryo stage in from ten days to two weeks when conditions of temperature and moisture are suit- able. Eggs and newly hatched embryos are very sensitive to freezing or drying, and easily die under these conditions. En- sheathed embryos are very resistant. We cannot depend on 149. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Reynolds, Myron Herbert, 1865-. New York, The Macmillan Company
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectveterin, bookyear1922
