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21.
An osteodystrophy with features of both rickets and fibrous osteodystrophy was diagnosed in growing pigs housed indoors and fed on a diet deficient in vitamin D. Affected pigs were severely lame and preferred to remain recumbent. At necropsy, the long bones had reduced breaking strength and in one five-month-old pig the articular surfaces of both proximal humeri were indented due to collapse of subchondral bone. Microscopic changes in the bones included prominent osteoclastic activity in the proximal metaphyses, variable myelofibrosis, trabecular microfractures, and focal thickening of the hypertrophic zone in some growth plates. Treatment consisted of an injection of Vitamin D3, addition of dicalcium phosphate to the diet for 18 days and long-term supplementation of the diet with fat-soluble vitamins. This is the first report of an osteodystrophic disease in pigs in New Zealand.  相似文献   
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1. Comparisons of the effects of age (up to 364 d) and sex on the rate of growth, eviscerated yield, blood loss and yield of skin, breast, thigh and drumstick muscles, heart, liver and gizzard have been made on a commercial British broiler strain.

2. Male broilers grew linearly up to 76 d whereas the females grew more slowly after 35 d. At 364 d the difference in live body weight was small.

3. Up to 56 d, males had a slightly higher eviscerated yield. There was no significant difference between the sexes beyond this age.

4. The proportional yield of breast muscle was variable with age, whereas that of thigh and drumstick increased with age in the male, particularly at 175 and 364 d.

5. After 35 d the proportion of skin was larger in females, whereas the gizzard as a proportion of live body weight in both sexes decreased rapidly between 21 and 76 d. Blood loss during killing was always higher in male broilers after 21 d.  相似文献   

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The effect of low grade chronic Fasciola hepatica infection on the concentration of plasma glutamate dehydrogenase (GD), gamma-glutamyl transpeptidase (gamma-GT) and aspartate aminotransferase (AST) was investigated in sheep dosed daily with three (AL3), eight (AL8) or 14 (AL14) metacercariae over 22 weeks or given a single dose of 200 metacercariae. Significant increases in plasma GD activity first occurred after nine, 12 and 23 weeks and in gamma-GT activity after 12, 24 and 32 weeks for groups AL14, AL8 and AL3 respectively. Changes in AST activity were not as clearly related to dose level. In sheep with single infection, both GD and gamma-GT were capable of detecting liver damage resulting from the migration of 10 or more flukes. Plasma GD and gamma-GT activities are more sensitive indicators of liver cell damage in chronic subclinical fascioliasis than AST activity and gamma-GT may be more suitable as a diagnostic aid on account of its greater stability.  相似文献   
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1. Blackening of the skin in factory processed cooked hens has been associated with elevated copper levels.

2. The degree of blackening was not directly related to copper content although the latter level was always higher than in control hens.

3. Simulated factory procedures, using scald water at 53 °C or 60 °C containing 50 mg Cu2+/1 and 50 mg C12/1, produced blackened skins of varying intensity on cooking.

4. It is suggested that the problem arose from a malfunction of the chlorination plant which produced excessive levels of chlorine and low pH, followed by erosion of copper from water pipes and subsequent interaction of copper and chlorine with the chicken skin.  相似文献   

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The functional capacity of a mirex-induced, enlarged liver was studied in rats. The tests used were sulfobromophthalein clearance, hepatic cytochrome P-450 concentration, serum total protein concentration and electrophoretic pattern, serum total lipid concentration, serum glucose concentration, and the liver response to epinephrine. There was no indication of a loss of functional capacity in the enlarged liver. Sulfobromophthalein clearance and microsomal cytochrome P-450 concentration indicated an increase in total liver functional capacity. We conclude that mirex is not a direct hepatotoxin producing generalized parenchymal cell damage.  相似文献   
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