[Postparturient hemoglobinuria in a Quebec dairy herd (author's transl)]

Postparturient hemoglobinuria in a Quebec dairy herdA case of post parturient hemoglobinuria which occurred in a Quebec dairy herd is reported. Anemia and hypophosphoremia were present in many animals without any clinical signs, while others were showing severe signs of hemoglobinuria. History, diagnostic techniques and treatment are discussed.

Evaluation of various methods for the detection of enteropathogenic Escherichia coli in diarrheic calves

Evaluation of the Escherichia coli population in the small intestine of diarrheic calves was performed by estimating the number of colony-forming units and the observation of direct gram-stained smears of mucosal scrapings. Enterotoxigenicity of the isolates was determined by the infant mouse test and the ligated intestinal segment in calves. The influence of various broth culture media on the production of enterotoxin was also studied. Serologic characterization of the E coli isolates was performed. A total of 190 cases of diarrhea in bovine neonates was studied and it was found that enteropathogenic E coi was not responsible for more than 20% of the cases. A practical approach for the recognition of enteropathogenic E coli in a routine diagnostic laboratory is proposed.

The postulated role of feeder swine in the perpetuation of the transmissible gastroenteritis virus

Clinical, immunofluorescence and histopathological observations were found to be an efficient approach for the confirmation of the diagnosis of transmissible gastroenteritis in feeder swine. Two cases are reported to exemplify how feeder swine exposed to points of concentration such as holding areas, sales barns and auctions can play an important role in the epizootiology of transmissible gastroenteritis. A third field case is reported as an example of an outbreak of transmissible gastroenteritis beginning in feeder swine and then spreading to baby pigs on the farm. All baby pigs died that were born during the acute phase of the outbreak in the feeder swine. Baby pigs born shortly after the clinical signs had abated in the herd, and from sows that had been exposed orally to virulent transmissible gastroenteritis virus and vaccinated with a commercial transmissible gastroenteritis vaccine ten days before farrowing, survived. This was explained by a combination of a decrease in the amount of virus shed in the environment and the immunity induced in the sows. These observations of field outbreaks of transmissible gastroenteritis combined with recently reported experimental studies lend strong support to the hypothesis of a reservoir for transmissible gastroenteritis virus in feeder pigs. This reservoir would be based principally on the transmission of the virus on a continuous basis from the feces of recently infected pigs to susceptible pigs. Clinical signs of transmissible gastroenteritis in such pigs are difficult to recognize or absent and this contributes to the importance of the reservoir in the field.

The use of immunofluorescence techniques for the laboratory diagnosis of transmissible gastroenteritis of swine

Over a four year period, 74 of 250 field outbreaks of enteric disease (30%) and 110 of 440 swine (25%) were positive for transmissible gastroenteritis by immunofluorescence procedures. Of 141 swine from herds positive for transmissible gastroenteritis 110 (78%) were positive by fluorescent antibody techniques. The fastest, easiest to perform and most effective procedure was the examination of frozen sections of the jejunum from acutely ill animals by the fluorescent antibody tissue section technique. Only two herds were found to be positive by the fluorescent antibody tissue culture technique which were negative by fluorescent antibody tissue section technique. A considerable number of outbreaks, 21 of 74 (28%), of transmissible gastroenteritis were detected by immunofluorescence in swine over two weeks of age. The majority of outbreaks of transmissible gastroenteritis, 50 of 74 (68%), occurred in Missouri during the months of January through April and 63 of 74 (85%) during the months of December through May. The recurrence of the disease in a number of counties over a four-year period suggest the possibility of endemic foci.

A new device to support handicapped patients during venography or myelography

The authors describe a seating device which holds the patient in position when the x-ray table is tilted and permits non-weight-bearing venograms to be obtained in handicapped as well as normal patients. Simultaneous bilateral venography reduces the study time considerably. The device is also helpful in lumbar myelography in paraplegics.

The experimental infection of piglets with a porcine reovirus

A strain (Quebec) of reovirus isolated from the faeces of a pig with dysentery was neutralised by reovirus type 1 antiserum. Four of eight hysterectomy-produced, colostrum-deprived (HPCD) piglets dosed orally with the third cell culture passage of the virus developed diarrhoea and showed focal areas of villous atrophy in the small intestine. The virus was isolated from the intestinal tract of all eight specific pathogen free piglets, but not from three control animals. Nine germ-free piglets dosed orally with the eight cell culture passage of the virus showed neither clinical signs nor lesions, but virus was recovered from their intestinal tracts for 14 days after infection. No virus was isolated from four control germ-free piglets.

Cryogenic gamma irradiation of prototype pork and chicken and antagonistic effect between Clostridium botulinum types A and B

Inoculated, irradiated pork (2,300 cans) and chicken (2,000 cans) pack studies were performed to establish the 12D dose for these foods. Each can was inoculated with a mixture of 10(6) spores of each of 10 strains of Clostridium botulinum (five type A and five type B), or a total of 10(7) spores. The cans received a series of increasing doses of gamma rays (60Co) at -30 +/- 10 degrees C; they were incubated for 6 months at 30 +/- 2 degrees C and examined for swelling, toxicity, and recoverable botulinal cells. The highest rate of swelling for both foods occurred within the first week of incubation, and maximum swelling was observed within 4 to 5 weeks. The minimal experimental sterilizing dose (ESD) based on flat, nontoxic sterile cans was 3.0 less than ESD less than or equal to 3.2 Mrad for pork and 4.0 less than ESD less than or equal to 4.2 Mrad for chicken. An analysis of the partial spoilage data by extreme-value statistics indicated with 90% confidence that the rate of spore death in the two foods was not a normal distribution, but appeared to favor a shifted exponential function. Based on the latter distribution, and assuming one most resistant strain in the mixture of 10 used, the 12D dose computed to 4.37 Mrad, with a shoulder of 0.11 Mrad, for pork and to 4.27 Mrad, with a shoulder of 0.51 Mrad, for chicken. An assumption that there were two or more most resistant strains in the inoculum progressively lowered the 12D dose. There was an apparent antagonism between the irradiated type A and B viable strains in the two foods. Cans with type B cells and toxin predominated over cans with type A cells and toxin, but cans with a mixture of type A and B toxins predominated over cans with a mixture of Type A and B cells. At the highest sublethal doses, only type A cells survived in pork, but in chicken there was a least one type B strain that was at least as resistant as type A strains.

Studies of bone and soft-tissue tumours induced in rats with radioactive cerium chloride

A colloidal suspension of radioactive cerium chloride was inoculated into the hind legs of Sprague Dawley rats. Bone and soft-tissue tumours were induced at the site of inoculation in 77% of the animals. All bone tumours were osteogenic osteosarcomas. Soft tissue tumours were mostly malignant and were of various histological types, predominantly fibrosarcomas, haemangiopericytomas, angiosarcomas and rhabdomyosarcomas. A kinetic study showed that the doubling time (DT) of tumours was closely correlated with the anatomical site of tumour development: bone tumours had a DT of 17.4 +/- 4.3 days and malignant tumours which developed in soft tissues had a DT ranging from 7.4 to 8.4 days with the exception of two haemangiosarcomas which had a long DT of 17 +/- 0.6 days. Pulmonary metastases were frequent for osteosarcomas and tumours of vascular origin. This model of induction of bone and soft-tissue tumours in rats by injection of a colloidal suspension of radioactive cerium chloride offers the possibility of more comprehensive physiopathological and kinetic studies of these tumours and may constitute a good model for their human counterparts.

[Onchocerca cervicalis infection in Quebec: clinical signs and diagnostic methods]

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Induction in rats of paranasal sinus carcinomas with radioactive cerium chloride

A colloidal suspension of radioactive cerium stabilized in the form of hydroxide was inoculated into young Sprague-Dawley rats near the maxillary sinus. Well-differentiated epidermoid carcinomas of the paranasal sinus were obtained in 8 of 12 rats and in 8 of 9 animals that liver more then 200 days. Therefore, this istope was highly effectivein inducing tumors at the site of injection. The uniformity of the histologic type of tumors induced under these experimental conditions was remarkable.

[Analysis of radio-isotope tests "in vivo" and "in vitro" in the diagnosis of hyperthyroidism. Statistical study of parameters obtained from routine investigations in normal and hyperthyroid subjects (author's transl]

Considering recent progress which permits routine direct estimation of circulating iodinated hormones, classical investigations based on plasma iodine fractions (PBI 127, BEI 127, 127 IH) must be considered out of date for the routine diagnosis of hyperthyroidism. The best possible approach for the detection of hyperthyroidism by radio-isotope tests in vitro consists of associating a determination of the free thyroxine index and tri-iodothyronine. Certain types of hyperthyroidism, mainly in the goup of toxic adenomas, escape this detection in vitro, and justify the use of conventional in vivo tests whenever this diagnosis is suspected.

Pathological and microbiological observations made on spontaneous cases of acute neonatal calf diarrhea

The purpose of this report is to describe clinical signs, gross and microscopic lesions, bacteriological and immunofluorescence observations made on spontaneous cases of acute neonatal calf diarrhea (NCD) in dairy and beef herds. The following diagnostic tools were used: 1) direct smears of intestinal content, 2) Escherichia coli counts, 3) aerobic bacterial cultures of the small intestine and other organs (The O serogroup and the enterotoxigenicity of the E. coli isolated was determined), 4) detection of the two Nebraska NCD viruses (reo-like and corona-like) by the fluorescent antibody technique and 5) histological examination on different segments of the digestive tract. The following etiological diagnoses were suggested after post mortem examination of 55 cases of NDC (34 were submitted alive): reo-like virus only (1), reo-like virus + E. coli (4), reo-like virus + cryptosporidium (2), reo- + corona-like viruses (5), reo- + corona-like viruses + cryptosporidium (3), reo- + corona-like viruses + infectious bovine rhinotracheitis virus (1), coronavirus-like agent only (2), coronavirus-like agent + mycotic abomasitis (1), coronavirus-like agent + crytosporidium (1), E. coli only (6), cryptosporidium only (5), mycotic abomasitis (3), mycotic rumenitis + reticulitis (1) and undetermined (20). Most of the calves in the last group were submitted dead.

Transmissible gastroenteritis in feeder pigs: observations on the jejunal epithelium of normal feeder pigs and feeder pigs infected with TGE virus

Light and electron microscopy findings in the jejunal mucosa of the normal feeder pig and feeder pigs infected with transmissible gastroenteritis (TGE) virus are reported. Villi in the mid jejunum of the normal feeder pig were elongated, finger shaped and covered with a layer of columnar absorptive cells with a well developed and regular brush border. Severe lesions of villous atrophy were present in all jejunal segments of feeder swine killed 96 hours post infection with TGE virus. Atrophic villi were covered by flat to cuboidal cells with a poorly developed brush border in some areas. In other segments, cells varied in appearance from sub-columnar to columnar type of near normal appearance. The ultrastructure of the jejunal absorptive cells in the normal feeder pig was found to be similar to that described for the jejunal cells of other adult mammals. There were no significant indications of high pinocytotic activity. The epithelial cells covering the atrophic villi of TGE infected pigs had a fine structure similar to that described for the crypt cells, ranging in appearance from very immature to moderately differentiated cells. Microvilli were very short, decreased markedly in number and irregular in arrangement. The terminal web was poorly developed. Strands of rough endoplasmic reticulum were markedly diminished and an increase in free ribosomes was noted. The significance of these observations in explaining pathogenesis of TGE in feeder pigs is discussed.

A case of viral neonatal calf diarrhea in a Quebec dairy herd

This report is concerned with a consistent problem of neonatal calf diarrhea (NCD) in a dairy herd in which, for nearly two years, the morbidity had approached 100% and the mortality had varied from 20% to 45%. Generally, diarrhea appeared at three days of age. By the fluorescent antibody tissue section technique the two Nebraska NCD viruses (reo-like and corona-like) were detected in the cytoplasm of many absorptive cells of the small intestine from a calf submitted for necropsy. Reo-like virus antigen was not detected in the absorptive and crypt cells of the colon but coronavirus-like antigen was. An adenovirus was also isolated from the small intestine of this calf. The disease was reproduced experimentally in a two day old colostrum deprived calf with a bacteria free intestinal homogenate obtained from the naturally infected calf. Both Nebraska NCD viruses were demonstrated in this experimental animal. However, the adenovirus was not re-isolated. Histological lesions observed in the small and large intestines of the naturally and experimentally infected calves were similar and because of their good correlation with the immunofluorescent findings, a combination of the two Nebraska NCD viruses was thought to be a major cause of the neonatal calf diarrhea problem afflicting this dairy herd.

Transmissible gastroenteritis in feeder swine: clinical, immunofluorescence and histopathological obervations

Eight feeder swine (four to six months of age) were inoculated orally with 200,000 to 500,000 pig infectious doses (PID) of the Purdue strain of transmissible gastroenteritis (TGE) virus. Biopsies obtained from their small intestines were examined histopathologically and by fluorescent antibody tissue section technique at intervals that included 24, 48, 72 and 96 hours postexposure, and similar examinations were carried out at necropsy 168 hours postexposure. Evidence of virus infection was demonstrated in all segments of the small intestine except the upper duodenum and the viral antigen was found only in the cytoplasm of the absorptive cells covering the villi. Although six of the eight pigs failed to show clinical signs of TGE, typical microscopic lesions of villous atrophy with replacement of columnar absorptive cells by cuboidal cells were observed in seven pigs, and TGE virus antigen was demonstrated in the intestinal cells of four of eight pigs during the first week postexposure. The infection was usually mild to moderate and focal in the pigs without clinical signs of the disease and more severe and extensive in the pigs with clinical signs of the disease variable in severity. It was concluded that TGE virus probably replicated in all feeder swine exposed, and that the presence or absence of clinical signs of TGE in these pigs was related to the severity and extent of the villous atrophy and columnar cell replacement induced in their small intestines.

Application de la Trichromie Complémentaire à l'étude des complexes métalliques en solution

Complementary tri-stimulus spectrophotometry appears as an interesting method for investigation of metal complex equilibria in solution. This has been demonstrated on various examples including bivalent (copper, vanadyl) or trivalent (iron, aluminum, yttrium, lanthanum) metal ions coordinated by several organic ligands.The formation, pH range of existence, and the number of absorbing species in colored solutions of binary or ternary (particularly bimetallic) systems are easily determined by calculation of the complementary tri-stimulus co-ordinates.The advantages (and disadvantages) of the technique are discussed. This qualitative method appears to be very useful for a first approach of coordination phenomena but needs to be completed by quantitative studies using classical methods.