PubMed Health⌕ Search

Biomedical subjects

G Fecteau

Publications and source records attributed to G Fecteau.

At least 19 recordsLinked to original sources

Evaluation of the embryo transfer procedure proposed by the International Embryo Transfer Society as a method of controlling vertical transmission of Neospora caninum in cattle.

OBJECTIVE: To evaluate efficacy of embryo transfer into seronegative recipients, using the procedure proposed by the International Embryo Transfer Society (IETS), for preventing vertical transmission of Neospora caninum in cattle. DESIGN: Prospective clinical trial. ANIMALS: 87 recipient cows and heifers and their embryo transfer calves from 22 donors originating from 9 dairy herds. PROCEDURE: Neospora caninum serologic status of donors and recipients was determined before collection and transfer of embryos. Viable embryos were washed and treated with trypsin. Recipients in experimental groups A (n = 50) and B (29) were seronegative and received embryos from seropositive and seronegative donors, respectively. Recipients in group C (n = 8) were seropositive and received embryos from seronegative or seropositive donors. Antibody titers against N caninum were determined monthly during pregnancy in recipients and in calf blood samples collected at birth. Tissues collected from stillborn calves and aborted fetuses were analyzed histologically and by immunohistochemical (IHC) methods. RESULTS: 76 calves and 11 fetuses and stillborn calves were examined. All calves from groups A and B were seronegative (n = 70) or lacked evidence of infection by use of tissue analysis (9). In group C, 5 of 6 calves were seropositive at birth, and IHC results were positive for 1 of 2 calves. Vertical transmission rate was significantly lower in groups A and B (0%) than in group C (75%). CONCLUSION AND CLINICAL RELEVANCE: Embryo transfer into seronegative recipients, using the procedure proposed by IETS, is an effective way to prevent vertical transmission of N caninum. Results provide support for pretransfer testing of all embryo transfer recipients.

Animals↗

Failure of dogs to shed oocysts after being fed bovine fetuses naturally infected by Neospora caninum.

Neospora caninum is a protozoan that causes abortion in cattle. The dog has recently been identified as a definitive host for N. caninum. To verify if bovine fetuses can infect dogs, nine 2-4-month-old dogs were fed bovine fetuses naturally infected by N. caninum. None of the dogs excreted oocysts, seroconverted, had clinical signs or lesions compatible with N. caninum infection. Additional studies will be necessary to determine the natural mode of infection of dogs by N. caninum.

Animals↗

Virulence factors in Escherichia coli isolated from the blood of bacteremic neonatal calves.

Twenty-five Escherichia coli isolates from the blood of critically ill bacteremic calves sampled in two separate studies on a calf-rearing farm housing over 15,000 calves, in the San Joaquin Valley, California were studied. Isolates were characterized for O serogroups and for pathotypes as determined by the presence of specific virulence factors including heat-labile enterotoxin (LT), heat-stable enterotoxins a and b (STa, STb), verotoxins 1 and 2 (VT1, VT2), cytotoxic necrotizing factor (CNF), aerobactin, intimin Eae and P, F17 and CS31A fimbrial adhesins, and resistance to bactericidal effects of serum. These isolates constituted a heterogeneous group. However, isolates were mostly aerobactin positive and often resistant to the bactericidal effects of serum. Isolates of pathotypes O78 (n=6), O119:CS31a (n=3), and P positive but O non-typeable (n=3) were associated with a high mortality rate. The remaining isolates belonged to diverse pathotypes, often possessing the adhesins P, F17, CS31A and Eae but belonging to O serogroups other than O78 and O119, and were less frequently associated with mortality. Although no virulence factor common to all isolates was identified, the capacity to use iron by the presence of aerobactin which is important to the capture of iron was a predominant factor. Moreover, certain pathotypes appear to be associated with primary colisepticemia whereas other pathotypes may cause a bacteremia without necessarily leading to septicemia.

Adhesins, Bacterial↗

Rare detection of Neospora caninum in placentas from seropositive dams giving birth to full-term calves.

Neospora caninum is thought to be transmitted to cattle by dogs, the only known definitive host. Although aborted fetuses seem the most likely source of infective material for dogs, placentas from seropositive dams appear also as a potential source of infective material. The objective of the study was to evaluate the presence of N. caninum organisms in placentas of full-term calves born to seropositive cows. Sixteen placentas, 11 from Neospora-seropositive cows, were examined histologically and by immunohistochemistry and polymerase chain reaction (PCR) assay for the presence of N. caninum. Mild placentitis was observed in all placentas. Neospora caninum was not identified by immunohistochemistry, but placentas from 2 seropositive dams were positive for N. caninum by PCR. These results suggest that placentas of full-term calves from seropositive cows may be a potential source of N. caninum for dogs, but the incidence of this mode of transmission is likely to be low.

Animals↗

[Comparison of four protocols for preoperative preparation in cattle].

This study was designed to evaluate 4 preoperative skin preparations, that is, more specifically, to compare the efficacy of chlorhexidine gluconate (CG) and povidone-iodine (PI), as well as 2 hair removal techniques (clipper alone or clipper followed by razor) for preoperative skin preparation in cattle. The 4 protocols resulted in a significant decrease in the number of bacterial colony-forming units (cfu). Group 4 (clipping + shaving + CG) had a significantly lower number of preoperative cfu per gel plate compared with groups 1 (clipping + PI) and 3 (clipping + shaving + PI). Skin reaction frequency was significantly higher in groups 3 and 4 (47.8% for both protocols) than in groups 1 and 2 (clipping + PI or CG) (8.7% for both). Wound infection frequency was 4.3% (4/92) and no significant difference was observed between the 4 treatment groups. The 4 protocols tested were equivalent as to efficacy and satisfactorily decreased skin microflora. Clipping alone was shown to be preferable to clipping plus shaving as a method of hair removal in cattle, with fewer skin reactions and no more wound infections.

Animals↗

[Determination of the potassium balances in diary cows and the examination of daily and lactation period-associated variations.

The objectives of this study were to evaluate a method of determining the internal and external potassium balances in dairy cows and to determine daily and lactation period-associated variations of these balances. Ingested potassium, milk potassium concentration (LK) and potassium urinary fractional clearance (FeK) defined the potassium external balance. Serum (SK) and red blood cell (CIEK) potassium concentrations defined the potassium internal balance. Whole blood, urine, and milk were collected at different times of the day from 19 cows, grouped in 5 lactation periods. Significant differences were observed for LK between lactation periods. Significant variations occurred during the day for CIEK, LK, and FeK. Thus, in order to monitor potassium balances during a time period, samples should be collected at the same time each day. This method of determining both potassium balances simultaneously could be useful in the study of the bovine hypokalemia syndrome.

Animals↗

Multifocal subacute necrotizing encephalomyelopathy in a Simmental calf.

Multifocal subacute necrotizing encephalomyelopathy affects Simmental and Simmental-cross cattle. First clinical signs are ataxia and hind limb paresis. The characteristic gross lesion is bilaterally symmetrical, grey, depressed to cavitated foci involving nuclei in the brainstem. The caudal olivary nucleus is consistently involved. The etiology of the syndrome remains unknown.

Animals↗

Posttraumatic stress disorder arising after road traffic collisions: patterns of response to cognitive-behavior therapy.

Road traffic collisions (RTCs) are common precipitants of posttraumatic stress disorder (PTSD). Two preliminary studies suggest that cognitive-behavior therapy (CBT) is, on average, effective in treating this disorder, although the major patterns of treatment outcome remain to be identified. Such outcomes might include treatment response, partial response, and response followed by relapse. To identify these patterns. 50 people with RTC PTSD completed a 12-week course of CBT, with outcome assessment extending to 3-month follow up. Dynamic cluster analyses revealed 2 replicable patterns of outcome: one for responders (n = 30) and one for partial responders (n = 20). Partial responders, compared with responders, tended to have more severe pretreatment numbing symptoms and greater anger about their RTC, along with lower global levels of functioning, greater pain severity and interference, and greater depression and were more likely to be taking psychotropic medications. Responders and partial responders did not differ in homework adherence, number of sessions attended, therapist effects, or stressors occurring during therapy or in the presence or absence of RTC-related litigation. Implications for enhancing treatment outcome are discussed.

Accidents, Traffic↗

Vertical and horizontal transmission of Neospora caninum in dairy herds in Québec.

Neospora caninum is an important cause of abortion in dairy cattle. The objective of this observational study was to estimate the rate of vertical transmission of N. caninum in dairy herds in Québec and to investigate horizontal transmission in the same herds. The genealogy of cows from 23 dairy herds were examined. Prevalence of seropositive animals in herds studied varied from 4.3% to 61.8% (average, 21.9%). The overall rate of vertical transmission was estimated to be 44.4%, varying from 0% to 85.7%. Seven cases of horizontal transmission were identified in 6 of the 23 herds studied. Estimated vertical transmission rate varied from herd to herd, but appeared to be higher in herds with a high prevalence of seropositive animals. Although horizontal transmission was identified in 6 herds, it does not appear to be the major route of infection for N. caninum.

Animal Husbandry↗

Etiology, forms, and prognosis of gastrointestinal dysfunction resembling vagal indigestion occurring after surgical correction of right abomasal displacement.

The objectives of this study were to determine the etiology and types of vagal indigestion (VI) occurring after right displacement of the abomasum or abomasal volvulus (RDA/AV), and the prognosis for each type. Data of cows presented for RDA/AV from a retrospective (n = 288) and a prospective (n = 132) study were used. Vagal indigestion occurred in 39 and 22 cows in each study, respectively. A necropsy was performed in 29 cases. Gastric compartment dilation compatible with VI type III or IV occurred in 23 cases. An abnormal gastric wall was detected in 22 cases. Peritonitis was present in 18 cows. Vagal nerve lesions were present in 5 out of 13 cases studied. Clinical, hematological, and necropsy results suggested a classification of VI with respect to presence or absence of peritonitis. Gastric wall damage, peritonitis and vagal nerve lesions appear important in the etiology. Considering peritonitis occurrence, antimicrobial therapy appears necessary in the treatment of RDA/AV.

Abomasum↗

Benefits and problems with cloning animals.

Animal cloning is becoming a useful technique for producing transgenic farm animals and is likely to be used to produce clones from valuable adults. Other applications will also undoubtedly be discovered in the near future, such as for preserving endangered breeds and species. Although cloning promises great advantages for commerce and research alike, its outcome is not always certain due to high pregnancy losses and high morbidity and mortality during the neonatal period. Research into the mechanisms involved in the reprogramming of the nucleus is being conducted throughout the world in an attempt to better understand the molecular and cellular mechanisms involved in correcting these problems. Although the cause of these anomalies remains mostly unknown, similar phenotypes have been observed in calves derived through in vitro fertilization, suggesting that culture conditions are involved in these phenomena. In the meantime, veterinarians and theriogenologists have an important role to play in improving the efficiency of cloning by finding treatments to assure normal gestation to term and to develop preventative and curative care for cloned neonates.

Animal Husbandry↗

Treatment of hypernatremia in an acidotic neonatal calf.

A 7-day-old Jersey calf was evaluated because of diarrhea and pneumonia. The calf was hypernatremic, hypoproteinemic, and acidemic, and was treated initially with i.v. administration of fluids with sodium concentration (175 mEq/L) similar to the calf's serum sodium concentration. Sodium concentration of the administered fluids was gradually decreased over the following days, but the calf's serum sodium concentration decreased too rapidly, and the calf developed neurologic signs attributed to cerebral edema. Treatment with mannitol and i.v. administration of fluids with a higher concentration of sodium resulted in abatement of clinical signs. In calves, hypernatremia may develop over several days. Prescribing traditional isotonic or hypotonic fluids in such cases will be harmful, because during chronic hypernatremia, the brain's adaptive mechanisms involve accumulation of organic osmoles that may take several days to equilibrate across cell membranes, and cerebral edema may result. Administration of fluids containing sodium concentration approximately equal to the patient's measured serum sodium concentration is required to decrease serum sodium concentration more slowly than is possible with traditional isotonic fluids.

Acidosis↗

A questionnaire on the health, management, and performance of cow-calf herds in Québec.

Questionnaires were mailed to 520 cow-calf producers in Québec in order to compare management practices and herd performance according to herd size (small: < 40 females, or large: > or = 40 females) and in 4 geographic areas for the 1995 calving season. Owners of large herds adopted management practice and preventive measures more often than did owners of small herds. Average calving and weaning rates were 95% and 87% respectively. Average perinatal and preweaning mortality rates were between 4.9% and 5.6%. A greater percentage of owners with large herds than owners of small herds reported diarrhea and pneumonia problems. Among large herds, the number of herds experiencing pneumonia and calf mortality associated with diarrhea tended to be higher in areas of the northwest. Calf mortality due to pneumonia was higher in the northeast. No regional variation was found among small herds. Further research is needed to identify diseases risk factors.

Animal Husbandry↗

[Control measures for contagious enteric diseases in a veterinary teaching hospital].

Instructions and control measures related to enteric contagious diseases at the Veterinary Medical Teaching Hospital (VMTH) of the Faculty of Veterinary Medicine of the University of Montreal are presented. These control measures, which have given satisfactory results within the past decade, are exemplified by a salmonellosis outbreak that occurred in spring 1996 in the large animal clinic of the VMTH. Emphasis was put on the importance of antigenic and/or genetic characterizations of Salmonella isolates, in order to detect an eventual source of contamination, but also to determine the incidence of nosocomial infections among hospitalized animals.

Animals↗

Seroepidemiologic study of Neospora caninum in dairy herds.

OBJECTIVE: To identify risk factors associated with Neospora caninum infection in dairy herds in Québec and to estimate seroprevalence in case and control herds. DESIGN: Herd-based case-control and seroprevalence study. ANIMALS: 3,059 cows from 24 case and 22 control dairy herds in Québec. PROCEDURE: Blood samples were obtained from each cow, and sera were tested, using an ELISA, for antibodies to N caninum. Owners of herds answered questionnaires requesting information on demographics and herd management practices. Seroprevalence was compared between case and control herds, using the Mann-Whitney test. Risk factors were compared between case and control herds, using logistic regression. RESULTS: All case herds and 73% of control herds had at least one seropositive cow. Median seroprevalence was significantly greater among case herds (22.5%) than among control herds (7.5%). Dogs were found most often and in greatest numbers on farms housing case herds compared with control herds during the past 3 years. CLINICAL IMPLICATIONS: Although the exact role that dogs have in transmission of N caninum in dairy herds needs to be elucidated, dogs should have limited access to barns and cattle.

Animal Husbandry↗

Description of 14 cases of bovine hypokalaemia syndrome.

The records of 14 cases of bovine hypokalaemia observed between 1983 and 1996 were reviewed. The most common history included a protracted, often infectious, disease. All age groups were represented. Although previously reported as a risk factor, isoflupredone acetate had not been administered to five of the cases. The following clinical signs were recorded in 10 cases: abnormal position of the head and neck, severe weakness, rumen hypomotility or atony, abnormal faeces, anorexia and tachycardia. Cardiac dysrhythmia was observed in six cases. Acid-base imbalance (alkalosis in 10 cases), hyperglycaemia and increased activities of aspartate aminotransferase and creatine kinase were associated with hypokalaemia ranging from 1.35 to 2.49 mmol/litre. Treatments included symptomatic treatment, supportive care and potassium chloride given intravenously and orally at an average total daily dose of 42 g/100 kg bodyweight (26 g by mouth and 16 g intravenously) for an average of five days. Eleven cases recovered after an average of three days.

Animals↗

[Prevalence of infections caused by Salmonella spp. in cattle and horses at the Veterinary Teaching Hospital of the Faculty of Veterinary Medicine of the University of Montreal].

Bacteriologic detection of Salmonella spp. from feces of animals admitted to Veterinary Teaching Hospital of the Faculty of Veterinary Medicine, University of Montréal, in Saint-Hyacinthe was carried out during a 1-year period to estimate the prevalence of bovine and equine salmonellosis. Prevalence at the time of hospitalization was quite low: 1.4% in cattle and 1.7% in horses. Incidence was 15.1 cases/100 animal/year in cattle and 38.7 cases/100 animal/year in horses. Serotype typhimurium was the most prevalent in both species. In cattle, cases were evenly distributed over the year. In horses, a recrudescence of cases and a obviousness of transmission were apparent in April 1996.

Animals↗

Focal symmetrical encephalomalacia in a 6-month-old Dorset sheep.

Neurological examination of a sheep that had acute onset of recumbency and mental depression indicated a diffuse symmetrical thalamocortical lesion. Cerebrospinal fluid analysis suggested a degenerative central nervous system disease. Thiamin administration resulted in partial and temporary improvement. Brain histological lesions were typical of focal symmetrical encephalomalacia.

Animals↗