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Biomedical subjects

D R Hodgson

Publications and source records attributed to D R Hodgson.

At least 37 records · Page 2Linked to original sources
PubMed2002

The epidemiology of subfertility in non-seasonal calving dairy herds in the Camden region of New South Wales: description of population and incidence.

OBJECTIVE: To describe biographic, reproductive, production and disease characteristics of 965 Holstein cows from 10 non-seasonal calving dairy herds in the Camden region of New South Wales, and to describe the incidence of subfertility, that is, conception requiring > 2 inseminations, in this population. DESIGN: A retrospective epidemiologic study. METHODS: Computer records were used to determine biographic, reproductive, production and disease characteristics in all lactations that commenced between 1 July 1995 and 30 June 1996 and resulted in conception during that lactation. Differences in these characteristics among herds and between primiparous and multiparous cows were examined. The lactational incidence of subfertility for lactations commencing during the study period was determined. RESULTS: Ten herds with appropriate records and management structures entered the study. Herd size ranged from 86 to 203 lactating cows. Nutritional and reproductive management of these herds was typical of smaller pasture-based herds within the study region. Records from 1320 cows were available, of which 965 were considered suitable for descriptive analysis. Monthly variations in number of cows calving were noted, with number of lactations commenced by primiparous and multiparous cows peaking in January and October, respectively. Significant (P < 0.001) inter-herd differences for all reproductive, disease and milk production outcomes were detected for both the entire population and within primiparous and multiparous subgroups. Of 1041 cows submitted for insemination, 76 failed to conceive. The lactational incidence rate (LIR) of subfertility in all lactations was 21.1% (95% CI 19-24%). and among all cows conceiving was 22.8% (95% Cl 20-25%). The LIR of subfertility in primipara was 24.1% (95% Cl 19-28%) and varied widely between herds (10%-40%). The LIR of subfertility in multipara was 22.2% (95% Cl 20-25%) and also varied widely between herds (7%-46%). CONCLUSION: Parity and herd of origin should be considered in any further analyses of these data.

Animals↗
PubMed2002

The epidemiology of subfertility in non-seasonal calving dairy herds in the Camden region of New South Wales: preliminary investigation of risk factors.

OBJECTIVE: To investigate relationships between biographic, reproductive, production and disease traits and subfertility among 965 Holstein cows from 10 non-seasonal calving dairy herds in the Camden region of New South Wales. DESIGN: A retrospective case-control study METHODS: Biographical, disease and reproductive data were collated from computerised records for cows with lactations that commenced between 1 July 1995 and 30 June 1996 and univariable and bivariable associations with subfertility were determined. RESULTS: Records from 965 cows that conceived were considered for risk factor analyses. Associations between subfertility and a number of risk factors (P < 0.3) were detected. Significant (P < 0.05) risk factors for subfertility in multiparous cows included herd of origin and, after controlling for the effect of herd, subfertility in the previous lactation, greater than 62 days dry, parity greater than five, interval between calving and first recorded heat, metritis and cystic ovarian disease. Herd of origin and, after controlling for herd effects, dystocia, metritis and percentage of milk fat plus protein at the time of first service were significant (P < 0.05) risk factors for subfertility in primiparous cows. The direction and magnitude of these associations are presented. CONCLUSION: Subfertility has a similar rate of occurrence in the herds examined to that reported overseas. Although herd of origin has a substantial effect on individual risk of subfertility, cow-level risk factors for subfertility are likely to exist. Exposures differ between primiparous and multiparous cows.

Animals↗
PubMed2002

Predictive values, sensitivity and specificity of abdominal fluid variables in determining the need for surgery in horses with an acute abdominal crisis.

OBJECTIVE: To determine the predictive values, sensitivity and specificity of abdominal fluid variables associated with the need for surgery in horses with an acute abdominal crisis. DESIGN: Retrospective study. ANIMALS: Two-hundred and thirty-six horses examined for signs of abdominal pain between January 1993 and June 1999. METHODS: Breed, age and gender of the horse and colour, total protein concentration and total nucleated cell count of an abdominal fluid sample were recorded. Colour of the abdominal fluid was classified as normal if it was yellow and transparent. Turbid fluid or fluid that was serosanguinous or other colours was classified as abnormal. Protein concentration < or = 20 g/L and a total nucleated cell count < or = 5 x 10(9) cells/L were considered normal and values above these were considered abnormal. An abdominal fluid sample was classified as abnormal if one or more of the three variables were considered abnormal. Cases were defined as surgical when lesions identified at surgery or necropsy examination would not have resolved with medical treatment alone. Cases were defined as medical in horses that survived without surgical intervention, and those with a lesion found at surgery or necropsy that would have resolved with medical treatment alone. A third category was identified during the study as those diagnosed with Actinobacillus equuli--induced peritonitis. These horses were included in the study but not in the data analysis. DATA ANALYSIS: The association between the sensitivity, specificity and positive and negative predictive value of colour, total protein, and total nucleated cell count in the abdominal fluid and the need for surgery was calculated. RESULTS: There were 100 females and 136 males of mixed breeds, ranging from 3 days to 26 years of age that had an abdominocentesis performed during the specified period. There were 97 horses with a lesion classified as surgical, 91 horses with a lesion classified as medical and 48 horses with a diagnosis of A equuli-induced peritonitis. Colour of the abdominal fluid was recorded in all horses, protein concentration was recorded in 194 horses and total nucleated cell count was recorded in 179 horses. Abnormal abdominal fluid colour had a sensitivity, specificity, positive and negative predictive value of 92%, 74%, 79% and 89% respectively, associated with the need for surgery. Sensitivity, specificity, positive and negative predictive values for a serosanguinous abdominal fluid sample associated with the need for surgery were 48%, 99%, 98% and 64% respectively. Abnormal abdominal fluid protein concentration had a sensitivity, specificity, positive and negative predictive value of 86%, 75%, 77% and 85% respectively, associated with the need for surgery. The sensitivity, specificity, positive and negative predictive value associated with the need for surgery in horses with an abnormal total nucleated cell count in the abdominal fluid were 59%, 75%, 67% and 67%, respectively. An abdominal fluid sample classified as abnormal had a sensitivity, specificity, positive and negative predictive value of 92%, 74%, 79% and 89% respectively, associated with the need for surgery. CONCLUSION: Results of this study suggest that abdominal fluid sample analysis contributes to the decision to proceed to surgery, but is not a diagnostic panacea. Colour and protein concentration of abdominal fluid were the most useful variables in abdominal fluid for differentiating medical and surgical lesions. Colour and protein had a greater value in horses with a disease likely to respond to medical treatment (negative predictive value) than those with a lesion requiring surgery (positive predictive value) except when the fluid was serosanguinous. Abdominal fluid colour and protein are clinically relevant and easily measured in the field, providing immediate information without the need for sophisticated laboratory techniques.

Abdomen, Acute↗
PubMed2002

Effects of prolonged training, overtraining and detraining on skeletal muscle metabolites and enzymes.

Thirteen Standardbred horses trained intensively for 34 weeks and detrained for 12 weeks to investigate the effects of training, overtraining and detraining on muscle metabolites, buffering capacity and enzyme activities (CS, HAD and LDH). After a standardised exercise test to fatigue at 10 m/s (approximately 100% VO2max), there was significant depletion of [ATP], [PCr] and muscle [glycogen] and accumulation of muscle and plasma [lactate], [NH3] and elevated muscle temperature. After training, associated with increased run time to fatigue (148%), there was reduced depletion of muscle [glycogen] and increased [NH3] and muscle temperature at fatigue. Training resulted in increased muscle buffering capacity (19%) and activities of CS (29%) and HAD (32%) and reduced glycogen utilisation (1.32 mmol/s in week 1 to 0.58 mmol/s in week 32). Plasma [lactate] at fatigue increased with training as opposed to muscle [lactate] implying enhanced ability to remove lactate from muscle. Overtraining resulted in reduced run time and associated effects in overtrained horses. While muscle [glycogen] prior to exercise was lower in overtrained horses, glycogen utilisation/s was not reduced and it may not, therefore, have caused the reduced run time. Prolonged high intensity training caused primarily aerobic adaptations and poor performance associated with overtraining may not be due to metabolic disturbances.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed2002

Hyperhydration prior to moderate-intensity exercise causes arterial hypoxaemia.

The second day of a 3-day event is the most physically demanding of the 3 days. If this is performed under hot and humid environmental conditions, detrimental effects on cardiovascular and thermoregulatory function and, therefore, on exercise capacity, may occur due to exercise-induced dehydration. We hypothesised that the administration of fluid equivalent to 6% of the horse's bodyweight prior to a simulated second day of a 3-day event would increase plasma volume and limit increases in core temperature. Seven Standardbred geldings underwent a training protocol prior to the study. A standardised exercise test was developed for each horse so that exercise intensity at each phase would be the same percentage of the maximal heart rate for all horses. The exercise test involved 4 phases: Phase A involved 30 min exercise at 3.7 m/s (approximately 25% VO2max); Phase B 4 min exercise at 8 m/s (approximately 60% VO2max); and Phase C 50 min at 3.7 m/s, after which there was a 10 min rest. Phase D involved 14 min at 7.3 m/s (55% VO2max). In a cross-over design, horses were grouped randomly and allocated to either exercise with no fluid (control) or approximately 26 l isotonic fluid by nasogastric tube, 120 min prior to exercise. Arterial and mixed venous blood samples were collected prior to exercise, towards the end of each of the phases and during the rest period. The administration of fluid prior to exercise resulted in a pre-exercise bodyweight gain of 21.3 +/- 1.2 kg. Hyperhydration resulted in a greater degree of arterial hypoxaemia than the control group in Phases B and D, but not in Phases A and C or at rest. During Phases B and D, mean PaO2 values in the horses that received fluid were about 15 torr lower than in the control group, but there were no differences in PaCO2 values between the 2 groups. In both arterial and mixed venous blood, pH and HCO3- were significantly lower in the group that were hyperhydrated. We concluded that the most likely cause of the more severe arterial hypoxaemia in the hyperhydrated group during the intense exercise phase was some degree of pulmonary oedema, from the extravasation of the administered fluid. Hyperhydration prior to exercise may be detrimental to respiratory function and therefore care must be taken in administration of large volumes of fluid prior to exercise.

Animals↗
PubMed2002

Thermoregulatory-induced compromise of muscle blood flow in ponies during intense exercise in the heat: a contributor to the onset of fatigue?

Cardiac output (Q) and tissue blood flows (BF) were measured in four ponies at rest, after 30 min of moderate exercise (ME) (approximately 30% VO2max) and following moderately intense exercise (M-IE) (approximately 65%) until fatigue, in a mildly hot (MH) environment (dry bulb temperature = 41 degrees C, wet bulb temperature = 27.5 degrees C). Exercise at both intensities resulted in increases in Q (15.6 +/- 1.7 [rest] vs. 35.8 +/- 2.6 [ME] vs. 48.6 +/- 3.9 [M-IE] l/min) and VO2 (4.7 +/- 0.9 vs. 24.5 +/- 1.2 vs. 55.8 +/- 5.8 ml/kg/min). When compared to ME, M-IE resulted in decreases in BF to the skin (approximately 15%), nonworking muscle (46%), fat (93%), gut (56%), kidneys (57%), CNS (31-66%) and an increase in BF to respiratory (68%), limb (98.5%) and cardiac (50%) muscles. In contrast, BF to working muscle during ME in thermoneutral (TN) conditions (McConaghy et al. 2002) was higher than found during ME in MH. We calculated that limb BF was approximately 25% lower for ME in MH vs. ME in TN. Similarly, we estimated that limb BF during M-IE in MH was approximately 25% lower than for M-IE in TN. Attenuation of the increases in muscle BF during exercise in the heat may be a determinant of the onset of fatigue.

Animals↗
PubMed2002

Effects of somatotropin and training on indices of exercise capacity in Standardbreds.

The recent availability of recombinant equine somatotropin (eST) has led to concern about its use as an ergogenic aid in racehorses. This study was undertaken to investigate the changes in exercise capacity in maturing horses in a training programme, and to assess whether eST is an ergogenic aid to this group. We tested the hypothesis that the combination of training and eST, compared to training alone, would further improve exercise capacity in maturing Standardbreds, by virtue of ST's anabolic effects and potential to enhance cardiac function, circulating fluid volume and red cell mass. Twelve, untrained Standardbreds (mean +/- s.d. 20.7 +/- 1.1 months) were paired according to similar bodyweight and then assigned randomly to treatment or control group. The horses underwent a 12 week treadmill training programme. Methionyl eST (10 microg/kg for the first 7 days, then 20 microg/kg) was administered once daily, i.m., for 42 consecutive days (Weeks 4 to 9 inclusive) to 6 horses in the treatment group. All horses performed a standardised maximal exercise test to fatigue at Weeks 0, 3, 6, 9, and 12. During each exercise test VO2, VCO2, plasma lactate concentrations ([La]), heart rates, blood volume and total run time were measured. There was no significant effect of eST administration on VO2max, V200, V(LA4), LA9, red cell volume (RCV), plasma volume (PV), or run time to fatigue. Combining the data for all horses, training significantly altered the VO2max (mean +/- s.d. 98.2 +/- 11.1 ml/kg/min in Week 0 to 117.6 +/- 4.8 ml/kg/min in Week 12), V(LA4) (5.1 +/- 0.8 m/s to 7.4 +/- 1.0 m/s), LA9 (12.7 +/- 3.9 mmol/l to 7.1 +/- 1.9 mmol/l), RCV (46.3 +/- 4.7 ml/kg to 63.5 +/- 5.0 ml/kg), PV (46.0 +/- 4.8 ml/kg to 57.0 +/- 6.3 ml/kg), and run time to fatigue (431.8 +/- 30.9 to 490.2 +/- 30.5 s), but not V200 (5.0 +/- 0.5 m/s to 5.2 +/- 1.1 m/s). The administration of eST to young Standardbred horses in training did not significantly improve their exercise capacity or indices of fitness. However, these maturing horses demonstrated a rapid physiological response to training exercise. Further research is required to determine the relationship between exercise capacity and ST in the horse.

Age Factors↗
PubMed2001

Coughing in thoroughbred racehorses: risk factors and tracheal endoscopic and cytological findings.

A matched case-control study was made of 100 thoroughbred horses which were coughing and 148 control horses which were free of clinical signs of respiratory tract disease. The variables identified by multivariable conditional logistic regression as being significantly associated with coughing included age (the risk decreased with age), the stage of training (horses in early training were at greatest risk), the time since the last race (horses that had never raced were at greatest risk) and the time since they were last transported (horses transported more than 14 days previously were more likely to cough than those transported within the last week). The coughing horses were significantly more likely to have high scores for upper and lower tracheal mucus and pharyngeal lymphoid hyperplasia. In addition, the tracheal aspirates of the coughing horses had increased odds of neutrophilia and were more likely to have intracellular bacteria than the control horses. However, a considerable proportion of the control horses had cytological and/or endoscopic evidence of airway inflammation.

Age Factors↗
PubMed2001

Cardiovascular, haematological and biochemical responses after large volume blood collection in horses.

To determine whether removal of 20 mL/kg of blood (approximately 25% of blood volume) resulted in adverse physiological effects in donor horses, we removed this volume of blood from five horses and selected cardiovascular, haematological and biochemical variables measured during collection and for 31 days thereafter. We found that alteration in most variables occurred, although the changes in values usually remained within published reference ranges. Also, recovery of these alterations to pre-collection values was rapid, occurring within 24--48 h in most instances. We concluded that volumes of blood less than or equal to 20 mL/kg when collected appropriately from healthy donor horses result in no adverse acute or chronic physiological changes. These results suggest that horses undergo adequate physiological compensation when approximately 25% of blood volume is removed for the purposes of blood donation or production of plasma.

Acid-Base Equilibrium↗
PubMed2001

Evaluation of high-speed treadmill videoendoscopy for diagnosis of upper respiratory tract dysfunction in horses.

OBJECTIVE: To evaluate high-speed treadmill videoendoscopy as a diagnostic technique and document the abnormalities found in Australian horses referred for poor performance associated with abnormal upper respiratory tract noise but where a definitive diagnosis could not be made at rest. DESIGN: A retrospective clinical study using client-owned horses. PROCEDURE: The clinical records and videorecordings of all horses referred to the University of Sydney for poor performance associated with abnormal upper respiratory tract noise during a 13-month period were examined. Only horses with a normal physical examination including absence of lameness, and where a definitive diagnosis of the cause of the abnormal upper respiratory tract noise could not be made from the resting videoendoscopic examination were included in the study. The age, gender, breed of horse and the purpose for which the horse was used were ascertained from the record and videorecordings were reviewed by the authors and any abnormalities noted. RESULTS: There were 37 horses included in the study. An upper airway abnormality was identified during high-speed treadmill videoendoscopy in 73% of horses. One abnormality was identified in 22 horses, 2 abnormalities in 4 horses and 3 abnormalities in 1 horse. Abnormalities identified included laryngeal hemiparesis (n = 15), axial deviation of the aryepiglottic folds (n = 10), pharyngeal collapse (n = 3), dorsal displacement of the soft palate (n = 2), epiglottic collapse (n = 1), axial deviation of the vocal cord (n = 1) and laryngeal collapse (n = 1). CONCLUSIONS: The results of this study are similar to reports from overseas and suggest high-speed treadmill videoendoscopy appears to be a useful technique to diagnose the cause of upper airway dysfunction in Australian horses referred specifically for poor performance associated with abnormal upper respiratory noise. However, a diagnosis will not be made in all horses undergoing this procedure. There were five horses with two or three abnormalities none of which were apparent at rest. This would suggest that in all horses making abnormal upper respiratory noise associated with poor performance, even where an abnormality is identified at rest, high-speed treadmill videoendoscopy should be performed for a complete diagnosis.

Animals↗
PubMed2001

Peritonitis associated with Actinobacillus equuli in horses: 51 cases.

OBJECTIVE: To review the clinical findings, diagnosis and treatment of 51 horses with peritonitis attributed to Actinobacillus equuli. DESIGN: Retrospective study of clinical cases. METHODS: Breed, age and gender of horse, history, physical examination findings, treatment and outcome were determined from the hospital records of 51 horses in which a diagnosis of peritonitis attributed to A. equuli was made between January 1993 and June 1999. Results of abdominal fluid cytology and bacteriology, antimicrobial sensitivity patterns, haematology and faecal egg counts, when performed, were also retrieved. RESULTS: There was a variety of breeds of horses affected. There were 35 male and 17 female horses, aged from 9 months to 22 years, presented. Lethargy, signs of depression with mild to moderate signs of abdominal pain and inappetence were the most common reasons for presentation. Most horses had elevated heart and respiratory rates, an elevated rectal temperature and reduced intestinal borborygmi heard on auscultation of the abdomen. Abnormal colour with an elevated protein were features of an abdominal fluid sample in 98% of horses and a marked elevation in nucleated cell count was present in all samples. Pleomorphic gram-negative rods were seen on cytology in 53% of samples and a positive culture of A. equuli was returned in 72% of samples. Other laboratory findings in some horses included mild haemoconcentration, hypoproteinaemia, an elevated circulating nucleated cell count with a left shift, an elevation in fibrinogen concentration and an elevated faecal egg count. All horses demonstrated a rapid response to treatment with procaine penicillin alone, or a combination of procaine penicillin and gentamicin sulphate. Where antimicrobial sensitivity tests were performed, all but two isolates were sensitive to procaine penicillin. All horses responded to antimicrobial and supportive therapy and were discharged from hospital. CONCLUSION: Horses with A. equuli peritonitis present with similar clinical signs as horses with other causes of abdominal pain. However, these signs, when evaluated in conjunction with the results of abdominal fluid analysis and response to treatment, are characteristic of A. equuli peritonitis. Pleomorphic gram-negative bacteria may be seen on a cytological preparation of the abdominal fluid sample, and a positive bacterial culture may be obtained in some, but not all, cases. Most isolates are sensitive to procaine penicillin, so treatment with procaine penicillin and gentamicin sulphate is recommended until antimicrobial sensitivity is known.

Actinobacillus↗
PubMed2001

Surgical correction of carpal valgus deformity in three alpacas.

Two alpaca crias and one 14-month-old alpaca were referred for treatment of bilateral carpal valgus. In one cria, hemi-circumferential periosteal transection and elevation combined with an ulna osteotomy was performed initially without success, however transphyseal bridging with screws and wires was used successfully in both crias to straighten the limbs. As the distal radial and ulna growth plates had closed in the 14-month-old alpaca, bilateral wedge ostectomies of the distal radius and transfixation casts were used to straighten and stabilise the limbs. The ostectomy sites healed and the alpaca is ambulatory, although carpal flexion is significantly reduced. Until the relationship between the growth rate of crias and the success of hemicircumferential periosteal transection and elevation and ulna osteotomy is established, transphyseal bridging may provide a more reliable result in crias with carpal valgus deformity and open physes. Wedge ostectomy and application of a transfixation cast can be used to correct severe carpal valgus deformities in alpacas with closed physes.

Animals↗
PubMed2001

Use of quantitative analysis of sonographic brightness for detection of early healing of tendon injury in horses.

OBJECTIVES: To determine whether quantitative analysis of sonographic brightness could be used to detect healing of an induced injury of the superficial digital flexor tendon in horses and whether rate of healing was influenced by equine recombinant growth hormone. ANIMALS: 8 clinically normal Standardbreds. PROCEDURES: A localized injury was created in the left and right superficial digital flexor tendons of each horse by injection of 2,000 units of collagenase. After injury, 4 horses received equine recombinant growth hormone, a possible promoter of tendon healing. Sonographic images (7.5 MHz) of the flexor tendons and ligaments of the metacarpal region were recorded on videotape prior to injury and weekly for 7 weeks after injury. Images were digitized, and sonographic brightness of tendons and ligaments was calculated. RESULTS: Collagenase-induced injury was sonographically similar to naturally occurring injury. After injury, sonographic brightness of the tendon decreased; after 3 weeks, brightness progressively increased, although by 7 weeks brightness had not returned to preinjury value. Equine recombinant growth hormone had no significant effect on the rate of tendon healing, as evaluated sonographically or at necropsy. CONCLUSIONS AND CLINICAL RELEVANCE: As healing developed, alterations in sonographic brightness of injured tendons coincided with real changes in tendon structure. Quantitative sonographic brightness could be used to accurately monitor healing of equine tendon and ligament injuries and investigate the efficacy of various treatment regimens.

Animals↗
PubMed2001

A case-control study of respiratory disease in Thoroughbred racehorses in Sydney, Australia.

In order to investigate the role of infectious agents in the aetiology of lower respiratory tract disease in Thoroughbred racehorses, a matched case-control study was conducted. Cases were identified by the presence of coughing, and were compared to a control population matched on time of sample collection and location within the same training establishment. Tracheal wash samples were collected from 100 cases and 148 controls. Case horses were more likely than controls to have endoscopic and cytological evidence of airway inflammation. There was no significant association between serological evidence of infection by commonly implicated respiratory viruses and coughing. Similarly, mycoplasma were rarely isolated and were not associated with disease. In contrast, there was a strong association between isolation of greater than a total of 10(3) colony-forming units/ml of tracheal wash and coughing. Individual bacterial species associated with disease included Streptococcus zooepidemicus, Streptococcus pneumoniae, Streptococcus suis, Streptococcus sanguis, Pasteurella spp and Bordetella bronchiseptica. This study provides evidence of the role of bacterial infection in the aetiology of lower respiratory tract inflammation in racehorses. However, in 58% of cases, few or no bacteria were isolated. Hence, at the time of identification of disease, there was no evidence of viral, bacterial or mycoplasmal infection in the majority of coughing horses. The aetiology of the signs observed in these horses requires further investigation.

Animals↗
PubMed2000

Attitudes of Australian veterinarians about the cause and treatment of lower-respiratory-tract disease in racehorses.

A questionnaire was administered to members of the Australian Equine Veterinary Association to investigate their attitudes and behaviours regarding the cause, diagnosis and treatment of lower-respiratory-tract disease in racehorses. The most-important perceived risk factors related to the level of exposure and resistance to infectious agents, whereas factors associated with racing and climatic factors were lower ranked. By far the most-commonly implicated primary cause of disease was respiratory viruses. However, specific diagnostic tests (such as viral serology or virus isolation) were rarely performed. By far the most-common diagnostic procedure was auscultation (without a rebreathing bag). The relative importance of diagnostic procedures was influenced by the proportion of total workload comprising horse work. Many respondents believed that bacteria become secondarily involved in disease; accordingly, antibiotic therapy was the most-commonly reported therapy. However, bacteriology of lower-airway-fluid samples was not commonly performed. The most-commonly used antibiotics were the potentiated sulphonamides (either alone or in combination with mucolytics or bronchodilators), followed by procaine penicillin and penicillin combined with gentamicin. Mainly, treatment would appear to be based on empirical beliefs rather than exhaustive investigation of individual cases.

Adrenal Cortex Hormones↗
PubMed2000

Issues associated with the application to veterinarians of a mailed questionnaire regarding lower respiratory-tract disease in racehorses.

This study evaluated a questionnaire investigating the attitudes and behaviours of veterinarians regarding the cause, diagnosis and treatment of lower respiratory-tract disease in racehorses. The questionnaire was sent to all non-student members (648) of the Australian Equine Veterinary Association: two mailings and a single telephone contact (each separated by four weeks). Subsequent phases were only administered to those who had not responded to earlier phases. In total, 467 (72.1%) of the 648 mailed questionnaires were returned. Of these, 354 were usable. The remaining 113 respondents gave various reasons for not completing the questionnaire; the most common (68%) was that horses were not a component of their practice. Those respondents working primarily with horses required fewer phases to return the questionnaire. Although deviating from previously described questionnaire designs, the described protocol provided a reasonable response rate.

Animals↗