Research Articles (Companion Animal Clinical Studies)

Permanent URI for this collectionhttp://hdl.handle.net/2263/1803

News

Want to become a Submitter? Please e-mail Susan Marsh

For inquiries regarding this collection or items in the collection, please contact Susan Marsh Tel.: +27 12 529 8007

Browse

Now showing 1 - 20 of 385

Effects of haemorrhage and lactated Ringer's solution or tetrastarch 130/0.4 resuscitation on colloidal osmotic pressure and osmolality in cats
(Sage, 2025-04) Michaletos, Anthea; Breytenbach, Marinell; Zeiler, Gareth Edward; gareth.zeiler@up.ac.za
OBJECTIVES : To determine the effects of haemorrhage and fluid over-resuscitation on colloidal osmotic pressure of albumin (COP albumin), plasma (Posm) and effective (Eosm) osmolality in anaesthetised cats. METHODS : A total of six cats were given three treatments once, at 2-month intervals, in a randomised, crossover haemorrhage-resuscitation study. The treatments were divided into two phases, a controlled haemorrhage phase and a fluid resuscitation phase, as follows: (1) NoHR = no controlled haemorrhage and no resuscitation; (2) LRS = controlled haemorrhage followed by lactated Ringer’s solution infusion (60 ml/kg/h); and (3) TS = controlled haemorrhage followed by 6% tetrastarch 130/0.4 suspended in 0.9% saline infusion (20 ml/kg/h). The resuscitation fluids were administered for 120 mins. Data were collected before haemorrhage, before resuscitation and at 30 min intervals until 120 mins. Variables were calculated at each time point as follows: COP albumin = albumin concentration (g/l) × 0.57; Posm = (2 × sodium) + glucose + blood urea nitrogen; and Eosm = (2 × sodium) + glucose. All Posm and Eosm concentrations were measured as mmol/l. Data were compared using a general linear mixed model (significance: P <0.05). RESULTS : Mean ± SD total haemorrhage volumes for NoHR, LRS and TS were 10.2 ± 2.3, 29.3 ± 9.0 and 29.1 ± 6.3 ml/kg, respectively. The COP albumin decreased over time in all treatments regardless of volumes of blood lost and fluid administered. The decrease in COP albumin was profound and clinically relevant in LRS and TS (both P <0.001). There were no statistical differences in Posm and Eosm over time except in LRS at 90 (P = 0.004) and 120 ml/kg (P <0.001). CONCLUSIONS AND RELEVANCE : The COP albumin decreased in all treatments but to low and clinically relevant concentrations in LRS and TS, putting the cats at risk of fluid overload. There were no clinically relevant derangements in Posm and Eosm.
Relationships between arterial and central venous blood acid–base variables in anaesthetised cats during euvolaemic and hypovolaemic states
(Sage, 2025-03) Breytenbach, Marinell; Michaletos, Anthea; Zeiler, Gareth Edward; gareth.zeiler@up.ac.za
OBJECTIVES : The aim of the study was to determine differences, agreements and correlations of acid–base variables between arterial and venous blood gas in anaesthetised cats in a euvolaemic or hypovolaemic state. METHODS : A group of six cats was used in a prospective randomised crossover haemorrhage–resuscitation study. Anaesthetised cats underwent three treatments at intervals of 2 months. Each treatment had a controlled haemorrhage phase and a resuscitation phase. The haemorrhage phase is the focus of this study. Arterial (carotid artery) and central venous blood were drawn simultaneously from preplaced catheters before haemorrhage (euvolaemic state; mean ± SD blood loss 1.3 ± 0.3 ml/kg for pre-haemorrhage data collection) and soon after controlled haemorrhage (hypovolaemic state; mean ± SD blood loss 15.8 ± 9.9 ml/kg). Acid–base variables from arterial and venous blood were compared under euvolaemic and hypovolaemic states as follows: (1) a paired t-test to determine the differences between the two samples; (2) a Bland–Altman plot to evaluate agreement and establish maximum clinically acceptable differences (defined a priori); and (3) Pearson’s correlation with least squares linear regression to determine the strength of correlation between the variables. RESULTS : The differences in pH and partial pressure of carbon dioxide were statistically significant under euvolaemic and hypovolaemic states but would not alter clinical decision-making. Agreements were clinically acceptable for all acid–base variables, except for the bias observed in the partial pressure of carbon dioxide under a hypovolaemic state. Correlations for all variables were strong under a euvolaemic state but weakened under a hypovolaemic state. CONCLUSIONS AND RELEVANCE : Using central venous blood sampling for acid–base analysis was clinically acceptable compared with arterial blood in our haemorrhage–resuscitation cat model during early compensated hypovolaemia. However, the partial pressure of carbon dioxide should be interpreted with caution, especially during hypovolaemia. Further investigation is necessary to determine whether these findings can be translated to critically ill cats.
Exploring the impact of the female thoracic size, breast size and image receptor angles on the volume of missing breast tissue in mammographic imaging
(Elsevier, 2025-05) Pape, R.; Zheng, X.; Cowling, C.; West, C.; Carstens, Ann; Kostidis, M.; Bowmast, H.
INTRODUCTION : Optimal positioning in mammography and subsequent image quality can be impacted by thorax variability, breast size and the chosen image receptor (IR) angles. This study aims to explore the impact of the female thoracic size, breast size and IR angle on the volume of missing breast tissue (MBT) in mammographic imaging. METHODS : Sixty-three images were recorded: one craniocaudal (CC) at an IR angle of 0° for three sized breast phantoms attached to three sized thoracic models; and six mediolateral obliques (MLOs) at IR angles of 30°, 40°, 45°, 50°, 55°, 60° for three sized breast phantoms attached to three sized thorax models. Breast size was determined using the posterior nipple line (PNL) measurement and were recorded in millimetres. Breast volume was recorded in cubic centimetres. RESULTS : The breast size and breast tissue volume of a small thorax and large breasts was better visualised with increasing IR angles. Optimal MLO IR angles were determined for the combined average thorax with average breast at 55° and large thorax with large breast at 40° with minimum MBT values of 51.33 cm3 and 75.07 cm3, respectively. Female thoracic size, IR angle, and breast size are significant (p < 0.01) and have a positive impact on the volume of MBT. CONCLUSION : Optimal MLO IR angles were determined for the three breast phantoms attached to three thoracic models. Female thoracic size positively impacts the volume of MBT and in terms of clinical practice it is vital to adjust the MLO IR angle to ensure maximum breast tissue coverage. IMPLICATIONS FOR PRACTICE : These findings can be modelled in current clinical practice on women presented for mammography examinations with varying thorax and breast sizes, allowing optimal IR angle selection and therefore resulting in improved breast tissue inclusion and subsequently a more accurate breast cancer diagnosis.
A qualitative study of mammography best practice positioning for female body habitus and breast tissue inclusion in Australia
(Elsevier, 2025-05) Pape, R.; West, C.; Zheng, X.; Carstens, Ann; Cowling, C.
INTRODUCTION : Optimal positioning in mammography is key to maximise the inclusion of breast tissue on the image. This study aimed to explore the top performing Australian radiographers' mammography best positioning techniques for patients with various body habitus and their perspective on optimised breast tissue inclusion. METHODS : Twelve qualified Australian female radiographers with an age range of 20–70 years with equal representation from screening and diagnostic mammography settings were invited through Volpara® Health to participate in an online individual semi structured interview. Audio-recorded data was transcribed and analysed thematically. Key demographics of the participants include age, education, and mammographic experience. RESULTS : Three key themes emerged for the craniocaudal (CC) view and the mediolateral oblique (MLO) view: good communication, CC detector height and MLO image receptor (IR) angle. Responses to each theme were categorised under six female body habitus for both the CC and MLO views: small, average, large, rib hump, pectus excavatum and pectus carinatum. Effective communication was demonstrated as critical by radiographers during positioning for varied body habitus. A 45° angle was commonly used for an average, small and large body habitus. CONCLUSION : Appropriate and customised positioning and effective communication is important during mammography positioning to maximise breast tissue inclusion on the image. Routine CC and MLO positioning techniques cannot be applied for patients with extreme curvature of the thorax or protruding sternum and ribs. IMPLICATIONS FOR PRACTICE : It is critical for mammography screening programs to include a language interpretation service that targets patients from multiple cultural backgrounds to enhance effective communication during positioning. This study highlights best positioning technique by radiographers that may impact women with extreme thorax curvature or protruding ribs, and subsequent obstruction in optimal positioning.
Butorphanol–azaperone–medetomidine and ketamine–butorphanol–azaperone–medetomidine chemical immobilization in habituated subadult female giraffe (Giraffa camelopardalis)
(Elsevier, 2025-07) Pfitzer, Silke; Laubscher, Liesel L.; Raath, Jacobus P.; Semjonov, Aleksandr; Basson, Etienne P.; Wolfe, Lisa L.; Miller, Michael W.; Zeiler, Gareth Edward
Please read abstract in the article.
Two point-of-care cardiac Troponin I immunoassays have acceptable analytical performance for the detection of measurands of cardiac Troponin I cardiac muscle homogenates from southern-central black rhinoceros (Diceros bicornis minor) and southern white Rhinoceros (Ceratotherium simum simum)
(Wiley, 2025) Rautenbach, Yolandi; Meyer, Leith Carl Rodney; Goddard, Amelia; Buss, Peter Erik; Hooijberg, Emma Henriette
BACKGROUND : Skeletal and possible cardiac muscle damage has been reported in chemically immobilized and transported African rhinoceros during conservation-related activities. The extent of cardiac muscle injury in these rhinoceros is unknown due to a lack of validated cardiac troponin I (cTnI) assays. However, recently, five human cTnI assays were deemed suitable for analytical validation in African rhinoceros based on cTnI sequencing results. OBJECTIVES : The first objective was to validate two cTnI immunoassay point-of-care analyzers (POCAs) in African rhinoceros and, secondly, to perform quality control (QC) validation for the POCAs. METHODS : Analytical validation of the Stratus CS Acute Care Troponin I cTnI immunoassay and Atellica VTLi high sensitivity cTnI (hs-cTnI) assay was performed using rhinoceros serum samples and species-specific cardiac muscle homogenate. Experiments included precision studies, reportable range, hemoglobin interference studies, recovery studies, and detection limit studies, with results assessed against prescribed total allowable error (TEa) performance goals. Commercial quality control material (QCM) data were used to calculate bias and imprecision for QC validation. RESULTS : Imprecision was acceptable (1.9%-10.3%) and met low cTnI concentration performance goals. Reportable ranges were similar to the manufacturer's specifications. High hemoglobin concentrations in white rhinoceros resulted in a positive bias in the Stratus CS. A simple 13s QC rule using two levels of QCM and a TEa of 70% could be used in both analyzers, except at very low cTnI concentrations in the Atellica VTLi. CONCLUSIONS : Both cTnI POCAs are suitable for use in African rhinoceros, and analytical performance goals for low cTnI concentrations in hs-cTnI assays were met.
Use of a point prevalence survey to measure antimicrobial use and antimicrobial resistance in equine veterinary hospitals
(Wiley, 2025) Leus, E.K.; Collins, N.; Gruyaert, M.; Kennedy, R.N.; McConnell, E.; McGorum, B.C.; Luethy, D.; Sanz, M.; Versporten, A.; Viljoen, Adrienne; Lyle, C.H.
BACKGROUND : Antimicrobial resistance (AMR) is increasingly recognised in equine medicine. Antimicrobial use (AMU) is a key driver of AMR. OBJECTIVES : To pilot a point prevalence survey (PPS), based on the Global-PPS used in human hospitals, to obtain data on antibiotic prescribing and AMR in equine hospitals and to identify targets for improvement in AMU. STUDY DESIGN : Point prevalence survey. METHODS : Eight equine hospitals located in Australia, Belgium, South Africa, the United Kingdom and the United States were recruited. Data on AMU were collected from all in-patients on antibiotic treatment at 08h00 on four selected study days throughout the study year (2022). RESULTS : In total, 742 patients, 310 (41.8%) surgical and 432 (58.2%) nonsurgical cases, were evaluated and 58.7% (182/310) surgical and 25.9% (112/432) nonsurgical patients were on antibiotics. The most prescribed antibiotics were penicillin, gentamicin and trimethoprim sulfonamides. In 45.2% (215/476) of prescriptions, use was prophylactic. Therapeutic use was based on a biomarker in 48.8% (127/260) of treatments. A sample was submitted for culture in 56.9% (148/260) of therapeutic treatments. A positive culture result was reported from 49.3% (73/148) of samples, with an antibiogram available for 90.4% (66/73) of the positive cultures. An antibiotic use stop/review date was not recorded in 59.5% (283/476) of uses. MAIN LIMITATIONS : This PPS was a pilot study with a relatively small sample size and likely does not reflect AMU in all types of equine hospitals in all geographic locations. CONCLUSIONS AND CLINICAL RELEVANCE : The PPS identified multiple ways in which antibiotic prescribing could be improved. Targets identified for stewardship interventions included empiric use of European Medicines Agency Category A and B antibiotics, the high prevalence of prophylaxis and the lack of use of a stop/review date. The survey could be used as a repeatable tool to assess stewardship interventions in equine hospitals.
Equine colic outcomes and prognostic factors at a South African academic hospital (2019–2021)
(Medpharm Publications, 2025) Van der Merwe, L.M.; Schliewert, Eva-Christina
BACKGROUND : Colic is a common equine emergency requiring medical or surgical intervention. These interventions can be costly, making outcomes data and prognostic indicators essential for guiding referral and treatment decisions. OBJECTIVES : To determine survival rates to hospital discharge and evaluate prognostic indicators in equine colic cases treated at a referral hospital (Onderstepoort Veterinary Academic Hospital [OVAH], South Africa). METHODS : This retrospective observational cohort study analysed records from horses with colic that were presented to the OVAH from January 2019 to August 2021. Data included signalment, admission heart rate (HR) and packed cell volume (PCV), treatment type (medical vs. surgical), surgical diagnosis, postoperative complications, and survival to discharge. RESULTS : Of 415 cases, 375 were treated (292 medically, 83 surgically). 91% of medically, 77% of surgically treated, and 88% overall survived. Compared to a previous study, overall survival to discharge improved by 5% (p = 0.025), mainly due to improved surgical outcomes. Survival was associated with treatment type and surgical lesion site (lower for small intestinal than large intestinal lesions). Medically treated cases with an increased HR and surgical cases with a high PCV had lower survival rates. Signalment showed no association with outcomes. CONCLUSION : Survival rates to discharge were comparable to previously published international reports and showed significant improvement to previous results from the same institution, due to improved surgical outcomes. These findings can assist veterinarians in referral and treatment decisions. Further research on long-term survival and additional prognostic indicators is required to improve outcome predictions for equine colic treatment.
Influence of carcinoma and sarcoma on neutrophil gelatinase-associated lipocalin and symmetric dimethylarginine concentrations in dogs
(Wiley, 2025-03) Rixon, Anouska J.; Meyer, Evelyne; Daminet, Sylvie; Goddard, Amelia; Kongtasai, Thirawut; Pazzi, Paolo
BACKGROUND : It is unknown if tumors or concomitant renal disease influence neutrophil gelatinase–associated lipocalin (NGAL) and symmetric dimethylarginine (SDMA) concentrations in tumor-bearing dogs. OBJECTIVES : Determine the effect of tumor presence, tumor type, and metastasis on concentrations of serum NGAL (sNGAL), SDMA, urinary NGAL (uNGAL), and uNGAL-to-creatinine ratio (uNGAL/Cr) in dogs with carcinoma or sarcoma without clinically relevant renal disease. ANIMALS : Twenty-one dogs with carcinoma, 18 with sarcoma, and 20 healthy age-controlled dogs. METHODS : Concentrations of sNGAL, SDMA, and uNGAL, and uNGAL/Cr ratio were measured from banked samples collected during a previous prospective study. Patient clinicopathological and histopathology records were reviewed, and those with renal azotemia or moderate to severe histopathological renal abnormalities were classified as having clinically relevant renal disease. Biomarker concentrations were compared between tumor-bearing dogs without clinically relevant renal disease and healthy age-controlled dogs. Additionally, comparisons were made between dogs with carcinoma and sarcoma, as well as between dogs with and without metastasis. Correlations between uNGAL and sNGAL concentrations, along with acute phase protein (APP) concentrations, were also analyzed. RESULTS : Tumor-bearing dogs without clinically relevant renal disease had increased uNGAL/Cr (p < 0.001), but not sNGAL, compared with healthy controls. Although median SDMA concentrations did not significantly differ between groups, increased concentrations were found in 32% of dogs with carcinoma and 20% of dogs with sarcoma. No differences were found between dogs with carcinoma and those with sarcoma, or between dogs with metastasis and those without. Urinary and serum NGAL concentrations were moderately correlated, while weak to no correlations were observed with APPs. CONCLUSION : Carcinomas and sarcomas, but not metastasis, influence uNGAL/Cr and SDMA concentrations in dogs.
Influence of tibial plateau angle in cranial cruciate ligament-deficient stifle on patellar ligament strain : an ex vivo study
(American Veterinary Medical Association, 2025-02) Bester, Elizabeth G.; Zeiler, Gareth Edward; Stoltz, George G.; Oberholster, Abraham Johannes (Abrie); Kitshoff, Adriaan Mynhardt; elge.bester@up.ac.za
OBJECTIVE : The aim was to investigate the patellar ligament strain with varying degrees of tibial plateau angles (TPAs) after tibial plateau leveling osteotomy (TPLO) in a cranial cruciate ligament (CrCL)-deficient stifle during the stance phase. METHODS : 12 pelvic cadaver limbs were secured to a custom-built jig to mimic a loadbearing stance after which an axial load of 120 N was applied. Patellar ligament strain, change in strain, and percent change in strain were calculated on pre-TPLO (intact and transected CrCL) and post-TPLO tibial TPAs of −5°, 0°, 5°, 10°, and 15°. Strain was measured using a 3-D digital image correlation to calculate Green-Lagrange strain (E33). Data were compared using a linear mixed model and applying the Dunnett method of multiple comparisons (control was pre-TPLO intact CrCL). RESULTS : The post-TPLO TPAs of 0° and 5° increased in patellar strain compared to pre-TPLO intact CrCL constructs, whereas no significant changes were seen at a TPA of −5°, 10°, and 15°. Significant changes in patellar ligament strain were noted at a TPA of 0° and 5°. The percent change in strain differed at −5°, 0°, and 5° TPAs. The median magnitude of percent change in strain was 35.1%, 37.0%, 79.0%, −7.1%, and −21.1% for −5°, 0°, 5°, 10°, and 15°, respectively. CONCLUSIONS : Significant increases in patellar ligament strain (CrCL-deficient stifle) during the stance phase were observed at TPAs of 0° and 5°. CLINICAL RELEVANCE : A TPA post-TPLO > 5° and < 15° is less likely to cause an increase in patellar ligament strain; however, further research is needed to investigate the clinical relevance of these findings.
Closed laceration of the trachea, esophagus and guttural pouches in a mare caused by blunt trauma
(Elsevier, 2024-12) Lopes, M.A.F.; Hollenbach, Elza; Schliewert, Eva-Christina; Murphy, Mark-Anthony; Correa, Felipe
A mare was admitted for progressive swelling of the neck, lethargy and anorexia. Radiography revealed perilaryngeal, peritracheal, and periesophageal emphysema. Endoscopy revealed pharyngeal and tracheal roof collapse, and a small laceration on the trachea. Treatment with antimicrobials, fluids, and flunixin was initiated. To prevent exacerbation of the emphysema, temporary tracheostomy was performed. Clipping for the tracheostomy revealed a hoofprint mark on the ventral neck. Subsequent endoscopies revealed laceration of the esophagus and guttural pouch septum communicating with the visceral compartment of the neck. Four days after admission, an esophagostomy was performed to prevent leakage of ingesta into the neck and allow feeding. Complications occurred: Deep cervical infection requiring surgical drainage; Esophageal impaction with shavings on one occasion causing extensive mucosa erosions; Laminitis managed with restricted physical activity and corrective farriery. Tracheostomy tube removal, esophagostomy tube removal, and patient discharge occurred 10, 36 and 51 days after admission, respectively. The mare did well after discharge and returned to competing in children’s showing classes. Blunt trauma to the neck can lacerate the trachea, esophagus and guttural pouches causing emphysema and deep cervical infection, which can be treated with antimicrobials, temporary tracheostomy, temporary esophagostomy, surgical drainage, and supportive care.
23rd Sharjah International Conservation Forum for Arabia's biodiversity
(Cambridge University Press, 2024-07) Seddon, Philip; Els, Johannes; Steenkamp, Gerhardus; Mallon, David; Senn, Helen; May, Sarah; Budd, Jane
No abstract available.
Suspected bacterial ventriculitis in a nine-month-old Goldendoodle
(Medpharm Publications, 2024-11) Loubser, L.C.; Botha, Willem J.; Le Roux, Christelle
Bacterial ventriculitis is an uncommon, often fatal complication of intracranial bacterial infection. This case report describes a nine-month-old spayed female Goldendoodle that presented with a history of acute onset generalised seizures. The initial clinical examination, neurological examination and minimum database laboratory tests were unremarkable, and the dog was diagnosed with probable idiopathic epilepsy. Three weeks thereafter, the patient developed breakthrough clustering orofacial and generalised seizures. Magnetic resonance imaging (MRI) findings were consistent with bacterial ventriculitis. Broad-spectrum antibiotic and supportive therapy was initiated pending cerebrospinal fluid (CSF) analysis, serology and bacterial culture; however, the patient died eight hours after initiating treatment. To our knowledge, this is the first case report of suspected bacterial ventriculitis in a dog in South Africa and describes its atypical clinical presentation, progression and unique MRI findings.
Surgical management of cranial cruciate ligament rupture and concurrent medial patellar luxation in a small breed dog by means of a modified cranial closing wedge ostectomy and tibial tuberosity transposition
(Medpharm Publications, 2024-11) Triegaardt, C.F.; Elliott, Ross C.; Naude, Stephanus H.; Kitshoff, Adriaan Mynhardt
Medial patella luxation (MPL) is a common cause of hindlimb lameness in small breed dogs and is associated with concurrent cranial cruciate ligament (CCL) rupture in up to 40% of cases. This case report describes a surgical technique that addressed both conditions concurrently. A four-year-old castrated, male Yorkshire Terrier presented with a chronic (two months) intermittent grade 3/5 lameness of the right pelvic limb that progressed to an acute non-weight bearing grade 5/5 lameness (Impellizeri et al. 2000). A clinical diagnosis of a grade 3 MPL and a concurrent CCL rupture of the right pelvic limb was made. A modified cranial closing wedge ostectomy (mCCWO) and a tibial tuberosity transposition (TTT), with a wedge trochleoplasty, were performed. The patient recovered uneventfully, and no lameness was detected at six weeks follow-up. No lameness or other incidents were reported by the owner on telephonic contact three months postoperatively. A follow-up clinical evaluation and lameness examination were performed at 12 months, and there was, subjectively, no visible lameness, and the radiographs showed radiographic union. This surgical technique has been shown to be an effective and viable option in this small breed patient to treat both conditions in one surgical procedure, but warrants further investigation with larger case numbers.
Promoting rhinoceros welfare during transit : veterinarians' perspectives on transportation practices
(Medpharm Publications, 2024-11) Macha, E.S.; Meyer, Leith Carl Rodney; Leiberich, Marion; Hofmeyr, M.; Hooijberg, Emma Henriette; emma.hooijberg@up.ac.za
Despite translocation being a useful conservation strategy in rhinoceros management, morbidities and mortalities occurring during transportation pose a significant concern to rhinoceros managers, veterinarians, and scientists. The objectives of this study were to better understand the effects of transport on rhinoceros and to gain insights from veterinarians involved in rhinoceros translocations about current practices and potential interventions that could improve welfare. A weblink and QR code to an online questionnaire with a total of 46 questions in Google Forms was sent to veterinarians who had experience in African rhinoceros transportation, through personal emails and social network forums. Results demonstrated that despite dehydration and negative energy balance being reported as the major causes of morbidities and mortalities during transport and post-release, most veterinarians (30/35; 86%) involved in rhinoceros translocation did not offer water, parenteral fluids, or feed to transported animals, for logistical reasons and the knowledge or perception of rhinoceros' resistance to taking ad lib food and water during transport. However, 52% (15/29) and 41% (15/34) of participants suggested that parenteral fluids could be used as an intervention to mitigate dehydration and negative energy balance respectively. To reduce stress, 94% (33/35) of respondents suggested the use of tranquilisers and sedatives. This study is the first to systematically investigate and report on practices by veterinarians involved in rhinoceros translocations globally. The study highlights that further research is required to explore optimal and pragmatic techniques in the field to mitigate reported welfare challenges in rhinoceros during transport.
Exploring the anatomy of Linguatula serrata using micro-computed tomography
(Elsevier, 2024-12) Birckhead, Alice; O’Hare Doig, Ryan; Carstens, Ann; Jenkins, David; Shamsi, Shokoofeh
Micro-computed tomography (micro-CT) is an emerging tool in parasitology that can assist in analysing morphology and host-parasitic interactions. It is a non-destructive, cross-sectional imaging technique that offers good resolution and the ability to create three-dimensional (3D) reconstructions. Here, we used micro-CT to study Linguatula serrata, which is a zoonotic pentastome parasite that infects dogs and ruminants throughout the world. The aims of this study were to describe the internal and external anatomy of adult L. serrata specimens using micro-CT, and to describe and compare specimens stained with 0.3% phosphotungstic acid (PTA) and 1% iodine (I2). Ten adult L. serrata specimens were subjected to micro-CT examination. The specimens were fixed in 70% ethanol and stained with 0.3% PTA or 1% I2. Both stains offered good tissue contrast. The main identifying external features of L. serrata (hooks, mouth, buccal cadre) were clearly visible. Virtual sections and 3D reconstructions provided a good overview of the coelomic cavity, with visualisation of the digestive tract, nervous system, and male and female reproductive organs. These micro-CT images and morphological descriptions may serve as an anatomical reference for L. serrata, in particular, the internal anatomy which has not been described in recent years.
Genetic characterization of diagnostic epitopes of cardiac troponin I in African rhinoceros
(Sage, 2025-03) Rautenbach, Yolandi; Parsons, Sven David Charles; Loots, Angelika Katrin; Goddard, Amelia; Meyer, Leith Carl Rodney; Buss, Peter Erik; Hooijberg, Emma Henriette
African rhinoceros undergo chemical immobilization and prolonged transport during translocations for conservation purposes and, hence, experience several pathophysiologic changes, including skeletal muscle injury. Potential concurrent myocardial injury has not been investigated due to a lack of validated immunoassays. We aimed to use inferred cardiac troponin I (cTnI) amino acid sequences of southern white (Ceratotherium simum simum) and southern-central black (Diceros bicornis minor) rhinoceros to assess the potential usefulness of several commercial cTnI immunoassays for detecting cTnI in African rhinoceros. We extracted RNA from the myocardium of deceased rhinoceros (2 white, 1 black rhinoceros) followed by primer design, cDNA synthesis via RT-PCR, and Sanger sequencing. The inferred cTnI amino acid sequences were obtained from the mRNA transcript sequences. The homology of epitope binding sites recognized by capture and detection antibodies in 6 human immunoassays was visually evaluated using aligned inferred rhinoceros cTnI amino acid sequences. Percentage identity between white and black rhinoceros cDNA nucleotide sequences was 99%; inferred amino acid sequences were identical. There were 5 amino acid differences between humans and rhinoceros in the epitope binding sites of immunoassay antibodies; 5 assays contained antibodies against epitopes that were not conserved. For one assay, the single capture antibody targeted a short heterologous epitope (residue 87–91), and cross-reactivity with rhinoceros cTnI was deemed unlikely. For the other 5 assays, complete antibody-epitope homology, or the inclusion of multiple detection or capture antibodies, or targeting of long epitopes, indicated that these assays could be suitable for further investigation of cTnI measurement in African rhinoceros.
Calcium and magnesium abnormalities in puppies with parvoviral enteritis
(American Veterinary Medical Association, 2025-01) Mouton, Anneri; Celliers, Anri; Thompson, P.N. (Peter N.); Mellanby, Richard J.; Schoeman, Johan P.; anneri.mouton@up.ac.za
OBJECTIVE : To determine the association between ionized calcium (iCa) and/or total magnesium (tMg) and the development of sepsis and to investigate whether iCa or tMg is associated with mortality in puppies with canine parvoviral enteritis (CPE). METHODS : 64 client-owned puppies with CPE were enrolled in this prospective cohort study. Serum iCa and tMg were measured daily from admission until death or discharge. Fifteen healthy client-owned puppies were used as controls. RESULTS : Mean iCa concentrations of the CPE group on admission were significantly lower compared to the control group (1.35 mmol/L vs 1.52 mmol/L). Ionized calcium concentrations of nonsurvivors were significantly higher compared to survivors on day 2 but not on any other days. Puppies that were hypercalcemic on day 2 were also significantly more likely to die than normocalcemic puppies (OR, 10.7; 95% CI, 1.7 to 71). Ionized calcium was not associated with the development of sepsis on any day. In contrast, mean admission tMg concentrations of the CPE group were significantly higher compared to the control group (0.72 mmol/L vs 0.63 mmol/L). However, tMg concentrations were not significantly different between survivors and nonsurvivors nor were they associated with the development of sepsis on any day. CONCLUSIONS : On admission, puppies with CPE had lower iCa and higher tMg compared to healthy puppies, and higher iCa a day after initiation of treatment was associated with increased odds of mortality. CLINICAL RELEVANCE : The results of this study provide insight into calcium homeostasis in critically ill young dogs with CPE.
Computed tomographic characteristics of craniomandibular osteopathy in 20 dogs
(Frontiers Media, 2024-09) Lopez, Luis A.P.; Almansa Ruiz, Jose Carlos; Steenkamp, Gerhardus; Holdsworth, Andrew
Craniomandibular osteopathy (CMO) is a proliferative, self-limiting, nonneoplastic disease of growing dogs characterised by excessive new bone formation on the skull and mandible. The radiographic findings of CMO are well described; however, limited reports of the computed tomographic (CT) appearance are available. This paper aims to characterise the spectrum of CT findings that can occur with CMO. The study is retrospective, descriptive, multicenter, and includes 20 cases. Age at presentation ranged from 6 weeks to 12 months, with no sex predisposition. Scottish terriers were overrepresented (65%); other breeds included Cairn terrier, Jack Russell terrier, Staffordshire bull terrier, labrador retriever, golden retriever, akita and Slovakian roughhaired pointer (one of each breed). Terrier breeds represented 80% (16/20) of the patient cohort. Mandibular osteoproliferation was present in all patients (marked in 80%, bilateral in 95%), affecting the rostral mandible in 25%, body in 85%, and ramus in 80%. Tympanic bulla osteoproliferation was present in 60% (12/20) of patients (all marked, bilateral in 75%). Cranial osteoproliferation (frontal, parietal, temporal, occipital bones or maxilla, or combinations of them) was present in 90% (18/20) of patients (40% marked, 27% moderate, 33% mild). Nasopharyngeal narrowing was seen in all 12 patients with tympanic bulla osteoproliferation (67% marked, 27% moderate) and caused nearly complete occlusion in two of them. External ear canal stenosis was seen in 55% (11/20) of patients (63% marked, 37% moderate, all bilateral). Temporomandibular joint (TMJ) impingement was suspected in 83% (10/12) of patients with marked tympanic bulla osteoproliferation (75% bilateral). Osteolysis with a moth-eaten pattern was seen in the mandible of 10/20 dogs, the calvarium of 5/20 dogs, and the maxilla of 1/20 dogs (5%). Lymphadenomegaly (mandibular and medial retropharyngeal) was found in 15/20 patients (70% mild, 30% moderate). The most severe CT changes were seen in Scottish terriers. CT allows for detailed characterisation of the bony changes associated with CMO, including the effects occurring secondary to osteoproliferation surrounding the tympanic bullae such as TMJ impingement, external ear canal stenosis, and nasopharyngeal narrowing. Osteoproliferation affecting the cranium and the presence of osteolysis were seen more frequently in this study than previously reported in CMO.
Acute leptospirosis in horses : a retrospective study of 11 cases (2015-2023)
(Wiley, 2024-10) Ramsay, Lynette; Eberhardt, Christina; Schoster, Angelika
BACKGROUND : Reports of leptospirosis in horses are limited. OBJECTIVES : To describe the clinical and diagnostic findings of acute systemic leptospirosis in horses. ANIMALS : Eleven client-owned horses presented to an equine hospital because of acute onset of disease between 2015 and 2023. METHODS : Retrospective case series. Horses diagnosed with leptospirosis by 1 or more of urine PCR, serologic microscopic agglutination test (MAT), and histopathology. RESULTS : Common clinical signs included lethargy (10), anorexia (10), fever (9), tachypnea (9), abnormal lung sounds (9), and epistaxis (6). Acute kidney injury was present in all cases. Evidence of pulmonary hemorrhage and liver disease was found in 8 (73%) and 6 (55%) horses, respectively. In 6 (55%) horses, kidneys, lungs, and liver were affected. Urine quantitative polymerase chain reaction for detection of pathogenic Leptospira spp. was positive in 6 (55%) cases. On serology Leptospira interrogans serovar Australis, Autumnalis, and Bratislava accounted for 86% of all titers ≥1 : 800. Overall case fatality rate was 4/11 (36%). Main findings on necropsy were tubular necrosis, interstitial nephritis, hemorrhage in the alveoli, pulmonary edema, periportal hepatitis and necrosis, cholestasis, and cholangitis. CONCLUSIONS AND CLINICAL IMPORTANCE : Leptospirosis should be considered as a differential diagnosis in horses with evidence of acute systemic inflammation and acute renal injury, epistaxis, or hepatic disease. For increased likelihood of identifying positive cases, both MAT serology and urine PCR should be performed.

Browse

Recent Submissions