Evaluation of a serological test system for the diagnosis of natural Echinococcus granulosus infection in dogs using E. granulosus protoscolex and oncosphere antigens

Serum antibody responses in feral or domesticated dogs naturally infected with Echinococcus granulosus or/and other common helminths were examined in an enzyme-linked immunosorbent assay (ELISA) using antigens prepared from E. granulosus protoscoleces or oncospheres. The ELISA using the protoscolex antigen was optimised with serums from experimental dogs monospecifically infected with E. granulosus or other helminth parasites, and helminth-free dogs. Anti-protoscolex antibody was detected in 16 of 22 (72.7%) serums from feral dogs with E. granulosus burdens ranging from 300 to 302,600 worms per dog. Seven serums from feral dogs which did not harbour E. granulosus at autopsy but which originated from an endemic hydatid region were tested using protoscolex antigen, and 1 serum gave a positive reaction. One hundred and two serums from dogs known never to have been infected with E. granulosus all gave negative reactions to protoscolex antigen. The sensitivity of the ELISA test proved to be superior to that which has been achieved by arecoline purging as a method of diagnosis for E. granulosus infection in dogs. For use of the assay in hydatid control or eradication campaigns, its sensitivity can be increased by choosing a lower absorbance discrimination value above which serums are regarded as having positive reactions. However, this does introduce positive reactions of some serums from dogs infected with helminths other than E. granulosus. In further development of the assay, use of defined recombinant antigens may improve both sensitivity and specificity.(ABSTRACT TRUNCATED AT 250 WORDS)     

Canine leishmaniasis. A review based on 95 cases in The Netherlands

The clinically relevant aspects of canine leishmaniasis are reviewed. Included are data from 92 dogs imported from the Mediterranean basin and at least 2 autochthonous cases. New aspects on pathogenesis are presented, including evidence that canine leishmaniasis is an immune complex disease. Therapy with meglumine antimonate (Glucantime) is evaluated. The hazards of imported canine leishmaniasis for public health are discussed.     

The clinical pathology of heartwater. I. Haematology and blood chemistry

Clinical pathological studies were undertaken in 5 calves with experimentally-induced heartwater. The most important findings include a progressive anaemia which may be associated with bone marrow depression and fluctuations in the total and differential white cell count, of which an eosinopenia and a lymphocytosis were the most marked. A severe drop in serum protein, especially in the albumin levels, was observed in all 5 cases. This disease is probably associated with an increased capillary permeability, as the protein content of the pericardial fluid in 1 case that died, approximated that of the serum. The osmolality of the effused fluid was also higher than that of the blood. No significant changes in the serum electrolyte levels occurred, except for total calcium levels which tended to decrease to below normal during the acute stage of the disease. Marked increases in total bilirubin were recorded. This, however, was not associated with liver pathology or haemolysis and may possibly be ascribed to a fasting hyperbilirubinaemia. Darkening of plasma colour was associated with peak rises in total bilirubin. Increases in both blood urea and creatinine levels indicate interference with renal glomerular filtration during the acute stage of the disease.     

Otitis externa. A disease of multifactorial etiology

Dogs and cats with long-standing otitis externa pose a difficult diagnostic challenge for the veterinarian, because chronically affected ears usually have the same appearance regardless of the underlying cause(s). In patients with chronic otitis externa, the disease is often caused by different combinations of primary, predisposing, and perpetuating factors. The unique therapeutic needs of each patient may be determined by careful interpretation of historical and physical findings, which should be supported by ancillary diagnostic tests.     

Isoleucine requirement of broiler chicks as affected by the concentrations of leucine and valine in practical diets.

1. Chicks were fed on an isoleucine-deficient diet, with 6 added concentrations of isoleucine to determine their isoleucine requirement and an additional 6 treatments were devised to determine their isoleucine requirement when dietary leucine and valine contents were increased. 2. The diet deficient in isoleucine contained 5.6 g/kg isoleucine with leucine and valine contents of 20.1 and 10.3 g/kg, respectively. Supplementation with leucine and valine increased these to 24.7 and 12.6 g/kg, respectively. 3. The isoleucine requirement was not affected by dietary leucine and valine contents in a diet with 13.4 MJ of ME per kg. Analysis of variance and Least Significant Difference of means indicated an isoleucine requirement of 7.2 g/kg. Non-linear regression of the same data indicated an isoleucine requirement of 8.44 g/kg, based on weight gain, or 8.19 g/kg based on food efficiency. 4. Reasons for the failure to find an imbalancing effect of branched chain amino acids in practical diets are discussed.     

Blood types in cattle of Iberian ancestry and in Holsteins at various altitudes.

Gene frequencies of RBC antigens were determined in Holsteins and Colombian (criollas) cattle living at 3,000 m, and in cattle descended from fighting bulls (Vacas de lidia) living at 2,500 m. These frequencies were compared with those of Holsteins, cattle native to Florida (scrub cattle), longhorns, and native cattle from Brazil (caracu cattle) living at sea level. The criollas, Vacas de lidia, scrub cows, longhorns, and caracu are descendants of original Iberian stock introduced to the Americas. We found that despite common ancestry (scrub cattle, long-horns, criollas, and caracu), genetic differences may have been derived through years of demographic isolation. The most remarkable blood-group differences were found in the high prevalence of the B system phenogroup (heritable group of antigenic factors) BQA'G'34 in the Vacas de lidia, and of the S system phenogroup U1H' in these cattle and in caracu. Furthermore, the gene frequencies differed in the Holsteins maintained at moderately high altitude (descended from Holsteins kept at sea level), and may have been reflective of the need to adapt to moderately high altitude and chronic hypoxemic conditions. Blood group polymorphism was found in all groups of cattle, although it was reduced in the Vacas de lidia, possibly because their breeding has been carefully controlled and they appear to be highly inbred.     

Application of in vitro fertilisation techniques to obtain calves from valuable cows after slaughter.

The ovaries of two infertile cows of high breeding value were recovered after slaughter, and a total of 222 oocytes were obtained. Of these, 156 were classified as of good or fair quality and were subjected to in vitro maturation, in vitro fertilisation (using frozen semen from three bulls of high breeding value) and in vitro culture procedures. After eight days, 27 embryos were obtained, of which 13 were transferred fresh, and 14 were frozen. Three recipients of fresh embryos became pregnant; two calved and one aborted at four months. One of eight recipients of frozen-thawed embryos became pregnant but aborted at three months.     

Bacterial endocarditis and inflammatory joint disease in the dog

The main clinical features of 12 cases of bacterial endocarditis were lameness, pyrexia, lethargy, anorexia and systolic cardiac murmurs. The lameness varied from generalised stiffness to an inability to stand and walk. Multiple joint involvement was typical. Two types of joint pathology were identified. A marked synovitis with granulation tissue sometimes covering the articular cartilage was present in some joints associated with the presence of bacterial organisms. Other joints proved sterile and showed a milder synovial pathology. In many dogs both an infective arthritis and a non-infective arthritis co-existed. Bilaterally symmetrical joint involvement was typical of the non-infective arthritis. The pathogenesis of the latter was likely to involve the deposition of circulating immune complexes (bacterial antigens, antibody and complement) in the synovium. The infective arthritis was presumed to be secondary to embolic disease, ie, the spread of infected emboli from the heart valve to the joints. Treatment was unsuccessful in all cases.     

Adenohypophyseal receptors for LHRH, pituitary content of gonadotropins and plasma concentrations of LH in cyclic, pregnant and postpartum beef cows

Adenohypophyseal concentrations of LHRH receptors, pituitary content of LH and FSH, and plasma concentrations of LH were determined in thirty Hereford, Angus or Hereford-Angus heifers that were randomly assigned by breed and weight to five periods including day 3 of the estrous cycle (CY), pregnant day 120 (P120), 200 (P200), 275 (P275), or day 2 postpartum (PP). Jugular blood samples were collected at 10-min intervals for 8 hr from all cows. Within 2 hr after completion of blood sampling, animals were slaughtered and the pituitary gland frozen at −196 C. LH pulse frequency/8 hr was reduced (P<.05) during gestation (.5, .2, and 1.5 ± .5/8 hr, for P120, P200, and P275, respectively) and PP (.5 ± .5/8 hr) compared to CY (7.8 ± .5/8 hr). Frequency of LH pulses/8 hr was not different (P>.1) among P120, P200 or PP periods but was different (P<.05) between P200 and P275. There were no differences in LH pulse height (P>.1) among periods; however, pulse amplitude was greatest (P<.05) at P120 (1.3 ± .2 ng/ml) and lowest between P200 and PP (.6 to .8 ± .2 ng/ml). Baseline concentrations of plasma LH did not differ (P>.1) among P and PP periods (.3 ± .1 ng/ml), but were lower (P<.05) than in CY animals (.7 ± .1 ng/ml). Concentration of adenohypophyseal LHRH receptors was approximately two-fold greater (P<.05) at P120 (25.85 ± 2.2 fmol/mg) than at all other periods (9.5 to 14.9 ± 2.2 fmol/mg). Pituitary content of LH was greatest at P120 (1.56 ± .11 ug/mg) and lowest (P<.05) at P275 and PP (0.46 to 0.52 ± .11 ug/mg). Pituitary content of FSH was greatest (P<.05) in P (12.7 to 17.0 ± 1.4 ug/mg) and PP (18.3 ± 1.4 ug/mg) vs CY (5.0 ± 1.4 ug/mg) cows and increased from P120 to PP (P<.05). Results indicate that physiological changes occurring during gestation may have an effect on subsequent function of the adenohypophysis in beef cows.     

Electron microscopy as an aid to the rapid diagnosis of virus diseases of veterinary importance

The use of electron microscopy to assist in the rapid diagnosis of virus diseases of veterinary importance is reviewed. Electron microscopy can be used to assist the laboratory diagnosis of a virus disease at two stages during the investigation; either by demonstrating virus in clinical material or by identifying isolates from tissue culture or similar systems. Direct electron microscopy and immunoelectron microscopy are particularly useful for rapid diagnosis. The advantages of electron microscopy lie in speed and flexibility, and the disadvantages in the high particle concentration needed and the presumptive nature of a diagnosis.