Ostertagia ostertagi infection in the calf: effects of a trickle challenge on appetite, digestibility, rate of passage of digesta and liveweight gain

The effects of a trickle challenge with the equivalent of 10,000 infective Ostertagia ostertagi larvae per day on appetite, digestibility, rate of passage of digesta and liveweight gain were investigated in 12 calves assigned to infected, pair-fed control and ad libitum-fed control groups. Digestibility of cellulose, nitrogen, organic matter and dry matter was determined using insoluble acid detergent fibre as a marker on two occasions during the study: (i) Between days 31 and 38, when abomasal dysfunction was greatest; and (ii) between days 52 and 58, beginning approximately one week after anthelmintic treatment (day 46). Rate of passage of digesta was measured using chromium mordanted hay, fed to each calf after each digestibility study period. Voluntary feed intake of the infected group was significantly reduced from day 37 with the greatest depression (77 per cent) occurring just before anthelmintic treatment. The drop in appetite was responsible for nearly 73 per cent of the difference in liveweight gain between the infected and ad libitum fed control groups. The apparent digestibility coefficient of nitrogen was significantly depressed (22 per cent) in the infected group though was restored to control levels by anthelmintic treatment. The rate of passage of digesta was significantly reduced in both pair-fed control (50 per cent) and infected (74 per cent) groups. Anthelmintic treatment increased the latter though only to pair-fed control group levels. It is suggested that the marked hypergastrinaemia seen in the infected calves may have been in part responsible for the decreased rate of passage of digesta and in turn for the drop in appetite.     

A Potential Screening System for Identifying Sorghum Ecotypes with Increased Lysine in the Seeds

Classical “high-lysine” sorghum lines are characterized by smaller seeds than average, due to a decrease in prolamin synthesis and a subsequent decrease in yield. To exploit the natural variation in lysine content and to identify ecotypes with a seed lysine content higher than average, characterized by plump seeds, a method was developed based on root-growth inhibition of seeds growing on a medium containing aminoethylcysteine (AEC), a lysine analogue. By using a collection of sorghum mutants and ecotypes a correlation coefficient of 0.926 between root length and lysine content was established. This method, which uses the root length of plants growing on aec to indicate which lines have a potential elevated lysine content, can be applied for the screening of sorghum germplasm. Since this is a non-destructive method it can also be used at the individual seed level, for example for screening progenies of regenerated plants from in vitro culture to exploit the somaclonal variation.     

Mucinous cholangiocarcinoma in a cat

Mucinous cholangiocarcinoma was diagnosed in a 14-year-old, castrated male, domestic shorthaired cat with marked peritoneal effusion. Cytological confirmation of malignancy by fluid analysis and fine-needle, ultrasound-guided aspiration of the liver was followed by histological examination of tissue samples obtained at surgery and necropsy. No observed response followed chemotherapy with doxorubicin and carboplatin. Electron microscopy and immunohistochemistry helped to further characterize this unusual tumor.     

A survey of the prevalence of Giardia in dogs presented to Canadian veterinary practices

Fecal samples (1216) were collected from dogs presented to 15 veterinary practices across Canada and tested for Giardia by ELISA for group-specific antigen. If positive, the presence of Giardia was confirmed by microscopy. Eighty-eight submissions tested positive by ELISA and microscopy. The overall prevalence rate of Giardia was 7.2%.     

Diversity,seasonality and sites of attachment of adult ixodid ticks on dogs in the central region of the Free State Province,South Africa

Several surveys of ticks infesting dogs belonging to owners in resource-limited and more affluent communities have been conducted in South Africa, but no such investigation has been carried out in the Free State Province of this country. The present study was initiated to meet this shortcoming. Ticks were collected from dogs at six localities in, and to the east of the city of Bloemfontein in the central region of the province. Three of these localities could be classed as resource-limited and two as affluent, while the sixth locality was an animal shelter serving all members of the public. Adult ticks belonging to nine ixodid tick species were collected, of which Rhipicephalus sanguineus was the most numerous. Significantly more R. sanguineus was collected from dogs at resource-limited than at more affluent localities. The greatest proportions of these ticks attached to the backs and necks of the dogs, with the proportions being larger in long-haired than in short-haired dogs. Most R. sanguineus were collected during the warmer months particularly from January to April. The greatest proportions of Haemaphysalis leachi, the next most numerous species, were also collected from the backs and the necks of the dogs. Most of these were present during the period September to November.     

Effects of interferents on the kinetic Jaffé reaction and an enzymatic colorimetric test for serum creatinine concentration determination in cats, cows, dogs and horses.

The effects of acetoacetic acid, acetone, bilirubin, beta-carotene, three cephalospoprin antibiotics, glucose, hemoglobin and lipid on the kinetic Jaffé reaction and an enzymatic reaction for the determination of creatinine concentration were studied in bovine, canine, feline and equine serum. There were no obvious species' differences. The kinetic Jaffé reaction was unaffected by the addition of beta-carotene and hemoglobin. Acetone, cefazolin, cefoxitin, ceftiofur and glucose caused a positive bias while acetoacetic acid, bilirubin, and lipid caused a negative bias when added to the kinetic Jaffé reaction. The enzymatic reaction was unaffected by the addition of acetoacetic acid, acetone, beta-carotene, cefazolin, cefoxitin, glucose and hemoglobin while added lipid, bilirubin and ceftiofur caused a negative bias in the test results. Over all species and interferents, there was no difference in the precision of the two assay methods. In a series of sera from hospitalized patients, the two methods were highly correlated in a linear fashion. The enzymatic creatinine assay deals effectively with most interferents but has a greater cost and shorter shelf-life compared with the kinetic Jaffé reaction.     

Spherocytosis associated with anaplasmosis in two cows

Spherocytes were detected on blood smears of 2 Angus cows. The RBC from both cows had increased fragility in hypotonic saline solution, supporting the presence of spherocytes. Other laboratory tests revealed a macrocytic, regenerative anemia with anisocytosis, polychromasia, basophilic stippling, Howell-Jolly bodies, nucleated RBC, and Anaplasma marginale organisms. A complement-fixation test was positive for anaplasmosis in cow 1 and a direct Coombs' test was positive for immunoglobulin G in both cows.     

Hepatopathy in 4 dogs treated with amiodarone

Amiodarone is a class III antiarrhythmic drug used in dogs with dilated cardiomyopathy and ventricular tachyarrhythmias. Hepatopathy is one of the more commonly reported adverse effects of amiodarone use in people. We describe 4 dogs that developed hepatopathy associated with amiodarone administration; 2 dogs also developed neutropenia. Three dogs had clinical signs of anorexia and lethargy; 1 did not show signs until impaired liver function had developed. Clinical signs or biochemical abnormalities developed 1.5-8 months after amiodarone treatment was started. Clinical signs resolved within 2 weeks of discontinuing amiodarone, but biochemical abnormalities did not resolve for 6-8 weeks. The delay between onset of liver disease and overt clinical signs suggests that serial evaluation of liver enzyme activities following amiodarone use in does is important.