Profiles of some clinical chemical parameters in growing dwarf and landrace kids.
Plasma creatinine, urea, bilirubin, glucose, cholesterol, calcium, magnesium, sodium, potassium, inorganic phosphorus and total serum proteins were analyzed in kids of Dwarf and Danish Landrace breeds from birth to 12 months of age. The purpose was to determine the reference ranges, age profiles and the influence of other factors. Comparisons between parametric (mean +/- standard deviation) and the corresponding nonparametric (5th and 95th percentile, median) values were calculated for each parameter, the results of which indicated no apparent differences. The levels were very much dependent on age. Creatinine, urea and total serum protein levels increased gradually with age. Glucose and cholesterol levels were high at birth and then decreased with age. The electrolyte concentrations were maintained within narrow limits. Significant differences were observed between kids of different ages (within the breeds), breeds (within similar age) and herds (within the same age and breed). Differences between female and male Landrace kids of the same ages were observed in plasma urea, creatinine, glucose and total serum proteins. It is concluded that age has a major influence on the clinical chemical reference values in young goats, followed by herd and breed, but the influence of sex was small and is negligible in most parameters.
Erythrokinetics and albumin metabolism in primary experimental Schistosoma bovis infections in Zebu calves.
Red cell kinetics and albumin metabolism were studied in calves infected with either 100 or 200 Schistosoma bovis cercariae per kg body weight, by the use of 59Fe-labelled transferrin, 51Cr-labelled erythrocytes and 125I-labelled albumin; a third group of worm-free animals acted as controls. The anaemia which developed in the infected calves was shown to be due basically to an accelerated rate of red cell loss from the circulation, and became evident around the seventh week of infection, increased in severity during the following two months, and subsequently subsided. In view of its close similarity to the pattern of faecal egg excretion, it was concluded that haemorrhage into the intestine caused by the exit of eggs was the principal aetiological factor: haemolysis was excluded by the absence of both splenomegaly and hyperferraemia . Erythropoiesis was also accelerated in infected animals, but could not keep pace with the rate of red cell breakdown to which the animals were concurrently subjected. Haemodilution was involved, but not to a significant extent. The hypoalbuminaemia associated with infection was caused by an increased rate of albumin catabolism, and a plasma volume expansion, and was accompanied by marked depletion of all albumin pools, but particularly the extravascular pool. The pattern of albumin catabolism closely followed that of red cell loss, suggesting that passage of plasma as whole blood into the intestine was the basic cause of hypoalbuminaemia. Red cell losses and albumin hypercatabolism were more severe in the more heavily infected group, and although both subsided as egg counts fell, they remained evident even 1 year after infection. This may partly explain the failure of infected animals to regain the weight lost during earlier stages of disease.
Immunisation of sheep against Schistosoma mattheei using either irradiated cercariae or irradiated schistosomula
Abstract Irradiated cercariae, irradiated schistosomula, or hcterologous infections were used to vaccinate sheep against Schistosoma mattheei infection. In the first experiment four doses of I04 S. mattheei cercariae irradiated at 6Kr were administered to sheep by percutaneous infection at 4 week intervals. This induced a 74% reduction in a challenge infection compared to control sheep while only 13% protection was achieved in a third group of sheep immunised with normal cercariae of the heterologous parasite S. mansoni. No significant differences were seen in histopathology of the liver of any of the sheep but the pathological changes were more severe in the large and small intestines of sheep vaccinated with the heterologous parasite. In the second experiment with irradiated cercariae only one or two immunising exposures were used. The degree of protection in the adult worm load (9–11%) was not significant and no significant differences were noticed in the pathology of the vaccinated and control animals. In the third experiment four doses of irradiated organisms were used to vaccinate five groups of sheep: 3Kr or 6Kr cercariae were administered by percutaneous infection; 6Kr skin-transformed scbistosomula were administered by intramuscular injection; the same 6Kr skin-transformed schistosomula were given by intravenous injection and 6Kr syringe transformed schistosomula were administered by intramuscular injection. The degree of protection (determined as the reduction in worm burden) achieved by these different procedures was respectively 72%, 61%, 77%, 56% and 78%. These results indicate the possibility of making a live vaccine against ovine schistosomiasis and show that effective immunisation is not dependent on the presence of a mature worm infection or on cercarial penetration of the skin by the immunising infection.