Journal of the South African Veterinary Association最新文献

Sporidesmin, a toxin released by a saprophytic fungus, Pseudopithomyces chartarum, causes hepatogenous photosensitivity in sheep and cattle, commonly known as Facial Eczema. A recent outbreak in the Eastern Cape Province of South Africa caused significant direct and indirect economic losses to a farmer in the area and highlighted the potential negative consequences of this mycotoxicosis to the dairy industry in this province. The milking herd consisted of 400 cross-bred Jersey/Friesian/Montbilliard cattle. The farmer identified 56 cows showing teat sensitivity/irritability during milking, hypersensitive skin, excessive licking and/or obvious skin lesions on non-pigmented skin areas. Three were culled due to the severity of their skin lesions. Grazing consisted of mixed kikuyu/perennial rye grass pasture under pivot irrigation, alternated with dryland kikuyu/Italian rye and sorghum. Typical clinical signs of severe secondary photosensitivity (skin inflammation and hypersensitivity to touch), very high serum concentrations of Gamma-Glutamyl Transferase (GGT 2143-5177 IU/L) and detection of large numbers of spores on grazed planted pastures supported the clinical diagnosis. Supplementation of zinc oxide (ZnO) powder at 12g per 500 kg cow dosed individually over the concentrates fed in the dairy, effectively reduced the incidence of new cases within two to three weeks. Weight loss, a decrease in milk volume and solids, and increased somatic cell counts were observed during this outbreak. One of these parameters, milk volume loss, was quantified by comparing the financial records of the four years preceding the outbreak to the production figures during the outbreak. The farmer lost approximately R1.5 million in milk volume during this outbreak (November 2020 - April 2021). Long term consequences were also apparent: the culling rate within the clinically affected group of 53 cows was more than 50% higher than the rest of the herd over the following two years. This case study highlights the urgent need to investigate the prevalence and potential economic impact of Sporidesmin Toxicity on the South African pasture-based dairy industry.

Population management of the African lion (Panthera leo) is often necessary in smaller non-contiguous systems. Ovariohysterectomies are commonly performed as a means of surgical birth control in many species by ventral-midline celiotomy, although a lateral laparotomy is used routinely in certain species and clinical settings. Ovariohysterectomies have been carried out in both captive and free-ranging African lion populations for birth control. This paper presents a left-lateral laparotomy (left-flank approach) for ovariohysterectomy in the free-ranging African lion, using the greater trochanter of the femur and the iliac crest as anatomical landmarks in order to determine the correct location for the abdominal incision. Unilateral ovariohysterectomies were successfully performed in three free-ranging lionesses by left-flank approach with no intra- or postoperative complications and rapid recovery. The procedure is swift, safe and provides an alternative to the ventral-midline celiotomy.

Background: Population numbers of free-roaming rhinoceros are dwindling while natural breeding in captive populations is challenged by sub-optimal fertility. When natural breeding programmes fail and population numbers continue to decline, the use of assisted reproduction technologies (ART) as a conservation tool to save wildlife species from extinction is imperative. Assisted breeding programmes in rhinoceros are challenging and attempts to develop species-specific ART beyond artificial insemination have been limited. This study evaluates various ex- and in-situ factors that could potentially affect in vitro oocyte maturation (IVM) in the Southern white rhinoceros (SWR).

Objective: To identify predictors of oocyte maturation following ovum pick-up (OPU) procedures performed on a large number of rhinoceros under different management conditions.

Methods: Data from 85 OPU procedures between November 2018 and June 2023 were obtained for this study. A total of 23 factors (three animal, four environmental, 16 laboratory) were evaluated as potentially affecting IVM success.

Results: Of the 85 procedures performed on 59 SWR, a total of 265 oocytes were collected with a median of two oocytes (range 0-18) per OPU. Eighteen (18) of the procedures yielded 0 oocytes. The overall maturation rate was 30% (80/265), and six identified factors had significant univariate associations with maturation outcome, of which three remained in the multivariable model.

Conclusion: Farming system, season and oocyte density in maturation medium (> 100 ul/oocyte) were independently associated with improved maturation success (p < 0.05).

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.

Objective: 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.

Background: Current literature most commonly describes the use of the dissociative drug ketamine for the immobilisation of baboons, either on its own or in combination with other drugs such as α-2 agonists or benzodiazepines. Currently, no reversal is available for ketamine, leading to prolonged and often rough recoveries of the animals, especially if high doses of ketamine are used.

Objective: In this study, the fixed-dose combination of butorphanol, azaperone and medetomidine (BAM) with a low dose of ketamine (K-BAM) was evaluated for immobilisation and recovery parameters of chacma baboons.

Methods: Fifteen baboons were immobilised and monitored. Actual doses administered: BAM 0.01 ± 0.005 ml/kg (butorphanol 0.31 ± 0.15 mg/kg, azaperone 0.12 ± 0.06 mg/kg, medetomidine 0.12 ± 0.06 mg/kg) and ketamine 2.04 ± 0.22 mg/kg. During immobilisation, heart rate (HR), respiration rate (RR), peripheral oxygen saturation (SpO₂), end-tidal carbon dioxide (EtCO₂), noninvasive blood pressure (BP) and blood gases were evaluated.

Results: Inductions were reached in 3.46 ± 1.36 minutes. Overall, severe hypoxaemia (SpO₂: 62 ± 13%; PaO₂: 37 ± 10 mmHg) was observed in all baboons as well as elevated EtCO₂ (63 ± 9 mmHg) and PaCO₂ (63 ± 9 mmHg) values. Other measured parameters stayed within normal ranges. Recoveries were fully reached at 4.8 ± 2.8 minutes after intramuscular injection of the reversal naltrexone and atipamezole.

Conclusion: BAM with a low dose of ketamine produced short-term immobilisation, allowing for minor veterinary procedures. The evere hypoxaemia observed in all animals, however, raises serious concerns regarding the safety of this protocol.

As a newly-minted veterinarian and aspirant pathologist, my first publication reported on an osteosarcoma at the thoracic inlet of a dog (Schröder 1976). The case was noteworthy because it was unusual for an osteosarcoma to originate on the axial skeleton, rather than on one of the long bones. Several years later, now wearing a parasitologist's hat, I have asked myself on numerous occasions if I might have missed an aetiological diagnosis of spirocercosis because I was too fixated on the neoplasm and its location. My only aide memoire is the paper from 1976, according to which I looked for and found metastases in the liver and lungs, but alas, no indication that I had also examined the oesophageal wall carefully.

Ulcerative balanoposthitis (UB) is a venereal disease which has frequently been diagnosed in sheep in South Africa (SA) since 1979, with no conclusive causative agent or treatment available. The purpose of this study was to determine whether ovine herpesvirus 2 (OvHV-2) can be used as biomarker to diagnose the early onset of UB in sheep flocks in SA. The study made use of 10 healthy Dohne Merino rams, two healthy Dorper rams, and 10 UB-affected Dorper rams. Smegma-, blood-, nasal swab- and sheath swab samples, respectively, were collected from all rams, and subjected to a single-tube hemi-nested PCR analysis to determine OvHV-2 status of all the sample types collected. The prevalence of OvHV-2 in all 22 animals was 22.75%, irrespective of breed or health status. The detection rate of OvHV-2 was 33.3% for the 10 UB-positive animals, and 16.7% for the 12 UB-negative animals. In blood, OvHV-2had a 4.54% detection rate, 8.33% in smegma, 13.64% in nasal samples, and a 0% detection in penile swabs. This study found nosignificant co-occurrence of UB and OvHV-2, which indicates that OvHV-2 cannot be considered as a biomarker for the early onset of UB or a causative agent of UB.

Many species of vulture are under threat from man-made inventions; this has led to wounded and sick vultures presenting for veterinary treatment and in need of pain management. Following the devastating effect of diclofenac on vultures in South Asia, meloxicam was found to be very safe for vultures, as a treatment as well as through ingestion of meat from treated animals. Many studies investigated the safety of meloxicam, and all found it to be safe up to 2 mg/kg, which was deemed the maximum likely exposure through treated carcasses. All studies exposed the birds either through oral dosing, treated meat or intramuscular administration, no instances of toxicity where recorded and all birds remained healthy. In this case the bird was exposed to a single dose of 2 mg/kg, intravenously, with no signs of toxicity. This appears to be the first recorded instance of accidental intravenous administration of meloxicam in a vulture.

Electrocardiography is the method used to monitor the electrical impulses in the heart. These diagnostics are increasingly making use of smartphone-based technologies. The objective of this research was to determine whether the Alivecor KardiaMobile (ECG_AKM) smartphone-modulated electrocardiographic device, a novel ECG device, can be used to obtain reliable electrocardiogram (ECG) readings in horses. The device was initially tested in 36 Nooitgedacht pony mares to determine the best site of application, method of skin preparation, and ECG_AKM device orientation for reliable ECG tracings. Once the most reliable site for ECG acquisition was determined, the device was then applied, in this manner, to 31 Nooitgedacht pony mares and compared with a standard telemetric ECG system (ECG_TV). The ECG_AKM device was best applied in the fourth intercostal space on the left hemithorax in a vertical orientation and with the skin dampened with 70% ethanol. Mean values determined for RR and QT intervals between the ECG_AKMS and ECG_TV were not significantly different, however, mean values for the duration of the QRS complexes were significantly different for the two devices. There is acceptable agreement between the ECG_TV and ECG_AKM devices with regards to the measurement of the PQ; RR and QT intervals but not the QRS duration. The automatically calculated heart rate is not an accurate measure of true heart rate. The Alivecor KardiaMobile (ECG_AKM) device can be considered as a simplified screening ECG device in situations where the more standardised system is either unavailable or impractical, but has some limitations.

The bioaerosol composition of the theatre environment plays a determining role in the development of surgical site infections (SSIs). It has been demonstrated that the concentration of viable airborne bacteria is influenced by the level of room occupancy, utilisation of surgical attire and importantly, proper ventilation systems, which are often lacking in the average veterinary facility. The aim of this study was to evaluate the airborne bacterial load encountered in non-environmentally controlled small animal veterinary theatres during routine surgical sterilisations, and to correlate these findings with the managerial practices at the facility. Four veterinary facilities with differing throughputs and managerial practices were recruited into the study. Blood agar settle plates, open from first incision to last suture, were used to quantify organisms that could settle in an incision. The 45 plates yielded 487 bacterial isolates (53 species). The Micrococcus (28.8%) and Staphylococcus (16.8%) genera were predominant. Of the isolates 61.8% were classified as human/small animal commensals and 37.2% belonged to species previously implicated in small animal SSIs. Specific trends were additionally evident in the bioaerosol loads. High room occupancy, lack of surgical attire and exposure to the outside environment were associated with higher bacterial counts. Accumulation from consecutive procedures was identified and linked to total occupancy time of the room. Current mitigation measures were not ideal to minimise the SSI risk. Routine, frequent and thorough cleaning in combination with surgical attire utilisation is recommended to reduce the bioburden for patient benefit.