Effect of D-glucose on in vitro short-circuit current in neonatal calf jejunum and rabbit ileum

Thin sheets of mucosa from small intestine of neonatal calves were mounted in incubation chambers for in vitro studies. These mucosal sheets generated a potential difference (PD) of 2.05 +/- 0.02 mV (mean +/- SEM), short-circuit current (SCC) of 23.32 +/- 3.81 microA x cm2, and tissue resistance of 86.22 +/- 4.41 ohms x cm2 (n = 6). Ouabain in the serosal bathing solution caused a sharp decrease in the SCC (P less than 0.01) and PD (P less than 0.005), a decrease in tissue K content (P less than 0.05), and an increase in tissue Na content (P less than 0.05). The mucosa responded to D-glucose by an increase in PD (P less than 0.001) and SCC (P less than 0.001). In vitro methods used in the calf were validated in similar experiments on rabbit ileum.     

Verification of ineffectual activity of ivermectin against adult Onchocerca spp in the ligamentum nuchae of horses

Ivermectin paste formulation (200 micrograms/kg) was administered orally to 27 horses (13 Thoroughbreds and 14 of mixed breeding) to evaluate activity against adult Onchocerca spp in the ligamentum nuchae. Ages, known or estimated, of the horses ranged from 1 to 22 years. Single or multiple doses (1 to 5) of the drug were given to each horse. When multiple doses were administered, the intervals between treatments ranged from 7 to 92 days. At 27 to 171 days after initial treatment (single dose or first of multiple doses), the horses were killed. Some of the horses treated more than once were killed as soon as 7 days after the last treatment. At necropsy, Onchocerca spp were found in the ligamentum nuchae of 24 (89%) of the 27 horses. All of the specimens were pieces of worms, apparently adult, which appeared to be alive. The only noninfected horses were 2 to 3 years old. In 18 (75%) of the 24 infected horses, microfilariae, most being obviously viable, were found in the worm specimens or ligamentum nuchae.     

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)     

Epidemiology of ovine helminthiasis in Haryana,India

Tracer lambs were used to study the pasture contamination with infective stages of helminth parasites during one annual cycle in a subtropical climate. Post-mortem worm counts indicated that low infections with Haemonchus contortus occurred throughout the year except in June. However, twenty five or more H. contortus per lamb were recorded in January, April, May and August. Trichostrongylus colubriformis infection was detected throughout the year and 150 or more worms per lamb were recorded during January to May and in August. Anoplocephalids were recorded from the lambs throughout the year but had no seasonal pattern. Low infections with Oesophagostomum columbianum and Trichuris ovis were observed. The faecal egg counts from the permanent flock with whom the tracer lambs were grazed revealed heavy to mild worm burdens throughout the year. Coproculture indicated that H. contortus predominated from the second fortnight of May to December except in the second fortnight of July. Infection with T. colubriformis was more severe from January to the first fortnight of May and in the second fortnight of July. Negligible infections with O. columbianum, Bunostomum trigonocephalum, Gaigeria pachyscelis and Dictyocaulus filaria were also observed. Biohythergraphs prepared for H. contortus and T. colubriformis showed differences between observed and expected results. It is suggested that for realistic biohythergraphs related parameters in addition to rainfall and temperature should also be considered.     

Effect of various treatments on the nutritional value of rye or rye fractions

1. Rye grain was subjected to several treatments in an attempt to alter its nutritive value for young chickens. 2. Soaking rye in water or dilute hydrochloric acid improved its nutritional quality. This was manifested by increased food intake, food utilisation, weight gain and increased apparent absorption of fat for chicks fed on a diet containing treated rye. 3. Autoclaving rye before water soaking eliminated the effect of soaking, an effect attributed to denaturation of endogenous enzymes which were responsible for the deactivation of the deleterious compound(s). 4. Autoclaving, sprouting and soaking rye in dilute sodium hydroxide decreased its nutritive value. 5. Studies with rye fractions demonstrated that the apparent absorption of fat was lower in birds fed on diets containing rye flour compared with those fed on diets containing rye bran, that greater improvement in apparent fat absorption occurred after water soaking of rye flour than similarly treating rye bran and that the effects were greater soon after initiation of the feeding of the rye diets as compared with the later part of the feeding trial.     

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.     

Immunological studies with liposome-bound corynetoxins

Attempts were made to raise antibodies against corynetoxins, a family of toxins responsible for annual ryegrass toxicity. The glycolipid nature of corynetoxins made them ideally suited for incorporation into the structure of small unilamellar liposomes. Sheep were injected with corynetoxin liposomes with and without adjuvants such as lipid A and muramyl dipeptide, and the sera tested for anti-corynetoxin antibody. Similarly, rabbits were injected with hydrolysed corynetoxin coupled to human IgG and keyhole limpet haemocyanin and with corynetoxin coupled to bovine serum albumin. These preparations were administered with complete Freund's adjuvant. The failure of any of these preparations to elicit an anti-corynetoxin antibody response in either sheep or rabbits is discussed.     

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.     

Biochemical analysis by SDS-PAGE and western blotting of the antigenic relationship between Leptospira and equine ocular tissues.

The antigenic relationship between Leptospira interrogans, equine cornea and lens was previously noted in our studies. Serum antibodies from horses inoculated with serovars wolffi, pomona, icterohaemorrhagiae, and tarassovi, were able to bind to five antigenic fractions from both cornea and lens, as demonstrated by immunoblotting. These antigens seem to be made up of protein and carbohydrates. After treatment with periodate for cleavage of glycoside ring structures, those fractions kept their condition of target for anti-Leptospira antibodies. Nevertheless, all fractions lost that condition after being subjected to peptide hydrolysis.