Common Emergencies in Rabbits, Guinea Pigs, and Chinchillas

Pain management in pet guinea pigs (Cavia porcellus): a review of limitations of current knowledge and practice

OBJECTIVE

To describe recent evidence-based and peer-reviewed literature on the topic of pain assessment and pain management in guinea pigs in a systematic review. To consider impacts of current practice on guinea pig welfare and to identify areas in need of further research.

DATABASES USED

ScienceDirect, PubMed and CAB abstracts along with relevant information from books and ebooks were searched. Terms used were guinea pigs, cavies, Cavia porcellus, pain, surgery, surgical procedures, grimace, dental, bloat, analgesia, non-steroidal anti-inflammatories and opiates.

CONCLUSIONS

There are few studies available in the areas of pain assessment and pain management in guinea pigs. Grimace scales and in-clinic pain assessment scales are available for other species but have not been developed for guinea pigs. Doses of analgesic drugs are extrapolated from other species or used from anecdotal evidence in the absence of validated values. The specified dose for the only UK licenced analgesic drug for guinea pigs (meloxicam) is significantly lower than doses suggested in the reviewed literature which may have a negative impact on the welfare of this species. To improve the welfare of guinea pigs, further research into the pharmacokinetic (PK) and pharmacodynamic (PD) properties of analgesic drugs specific to this species are required. Further research into the development and validation of pain assessment methods is also indicated to promote better welfare of this species.

Non-traditional small companion mammals in Spain as reservoirs of antimicrobial-resistant Staphylococci

Introduction

The increasing prevalence of antimicrobial resistance (AMR) and multidrug resistance (MDR) in microorganisms poses a significant concern in both human and veterinary medicine. Non-traditional companion animals (NTCAs), particularly popular amongst households with children, play a crucial role in AMR epidemiology due to their rising population. Indeed, it is known that some of these animals may act as reservoirs of zoonotic pathogens and thus be able to spread and transmit them to family members, along with their AMR, through their shared environment. It is therefore imperative to address this concern with the involvement of human, animal and environmental health professionals. This pilot study aimed to assess the prevalence and AMR patterns of Staphylococcus spp. strains obtained from commensal mucosal and skin infection samples in NTC small mammals, with a focus on strains like methicillin-resistant Staphylococcus spp. (MRS) that are critical in public health.

Methods

For this purpose, 81 animals of different small mammal species were sampled, assessing antimicrobial susceptibility to 27 relevant antimicrobial agents (AMAs) in human health using minimum inhibitory concentration assays, and interpreting them according to EUCAST and CLSI guidelines. The isolated Staphylococci strains were identified by MALDI-TOF, with the predominant species being Mammalicoccus sciuri and Staphylococcus aureus.

Results and discussion

Including all strains isolated, AMR was observed against all 27 AMAs, including six last-resort AMAs in human medicine. Additionally, over 85% of the strains exhibited MDR. These findings underscore the need to monitor AMR and MDR trends in companion animals and emphasise the potential role of NTCAs in spreading resistance to humans, other animals, and their shared environment, calling for a comprehensive "One Health" approach.

Fetal dystocia in guinea pigs: A case report

Dystocia is a common complication in guinea pig pregnancies, presenting significant challenges in clinical management. The present case report describes the presentation, diagnosis, and surgical intervention in an 8 months old female guinea pig with dystocia. The subject is a primiparous guinea pig originating from a commercial breeder, exhibited prolonged labor with two pups, one of which was stillborn. Physical examination revealed a distended abdomen, lack of uterine contractions, signs of distress, and vulvar discharge. Radiographic and ultrasound tests confirmed obstruction due to large fetal size and mineralization of the pubic symphysis. Surgical intervention proceeded with a ventral midline approach, ovariohysterectomy and removal of three fetuses. The guinea pig recovered well from the procedure, being discharged with postoperative care, and the use of anti-inflammatory, analgesics, prokinetics, antibiotics as well as scopolamine. The objective of the present work is to discuss and emphasize the importance of veterinary intervention, diagnostic evaluation and therapeutics for the multifactorial nature of dystocia management. Despite the surgical treatment, the prognosis for both dam and offspring remains guarded, highlighting the need for early detection and intervention to optimize outcomes in guinea pig dystocia cases.

Exploring the Prevalence of Antimicrobial Resistance in Salmonella and commensal Escherichia coli from Non-Traditional Companion Animals: A Pilot Study

Companion animal ownership has evolved to new exotic animals, including small mammals, posing a new public health challenge, especially due to the ability of some of these new species to harbour zoonotic bacteria, such as Salmonella, and spread their antimicrobial resistances (AMR) to other bacteria through the environment they share. Therefore, the objective of the present pilot study was to evaluate the current epidemiological AMR situation in commensal Escherichia coli and Salmonella spp., in non-traditional companion animal small mammals in the Valencia region. For this purpose, 72 rectal swabs of nine different species of small mammals were taken to assess the antimicrobial susceptibility against 28 antibiotics. A total of one Salmonella enterica serovar Telelkebir 13,23:d:e,n,z15 and twenty commensal E. coli strains were isolated. For E. coli strains, a high prevalence of AMR (85%) and MDR (82.6%) was observed, although neither of them had access outside the household. The highest AMR were observed in quinolones, one of the highest priority critically important antimicrobials (HPCIAs) in human medicine. However, no AMR were found for Salmonella. In conclusion, the results showed that small mammals' commensal E. coli poses a public health risk due to the high AMR found, and the ability of this bacterium to transmit its resistance genes to other bacteria. For this reason, this pilot study highlighted the need to establish programmes to control AMR trends in the growing population of new companion animals, as they could disseminate AMR to humans and animals through their shared environment.

Clinicopathological and radiographic indicators for orogastric decompression in rabbits presenting with intestinal obstruction at a referral hospital (2015-2018)

BACKGROUND

Orogastric decompression is regularly recommended as a part of both medical and pre-surgical treatment for small intestinal obstruction in rabbits. However, guidelines as to when orogastric decompression is indicated are sparse.

METHODS

The medical records of 35 rabbits diagnosed with gastrointestinal obstruction over a 3-year period were examined. Differences in presentation, clinicopathological and radiographic examination findings, treatments and outcome were evaluated.

RESULTS

Approximately 49% of the cases evaluated were considered to have non-life-threatening disease, while 51% were considered to have life-threatening disease. The severity of gastric obstruction was correlated with the severity of hyperglycaemia (average 25.7 mmol/L; 463 mg/dl) and corresponding hyponatraemia (Na < 138 mmol/L; 138 mEq/L). These patients were treated with orogastric decompression and medical management only.

LIMITATIONS

This is a retrospective study and there are inherent limitations involving the quality of the data and data collection. Additional studies should be completed that strive for larger sample sizes to compare the differences in outcome between surgical and medical management, as well as investigate the outcomes of rabbits with hyperglycaemia and hyponatraemia that did not have an orogastric decompression performed.

CONCLUSIONS

Blood glucose and sodium concentrations, in combination with radiographic findings, may aid clinicians in determining if orogastric decompression is indicated to stabilise rabbits with small intestinal obstructive disorders.

The clinical effect of intravenous lipid emulsion on rabbits medicated with diazepam

Intravenous lipid emulsions (ILE) have been increasingly used to reverse a wide range of lipophilic drug intoxications. However, it is still unknown if these emulsions interfere with other lipophilic drugs routinely used while treating intoxicated patients, such as diazepam, one of the main antiepileptic drugs. Therefore, the objective of the present study was to evaluate whether the administration of a 20% ILE interferes with diazepam's clinical effect. We randomly allocated thirty rabbits to five groups. Three of those groups received diazepam (1.0 mg/kg, IV), one of which did not receive any additional treatment, while the two remaining groups were treated with ILE or lactated ringer solution (1.5 mL/kg followed by 0.25 mL/kg/min for 30 min). The fourth group only received lipid emulsion, and the fifth only lactated ringer. Successive neurological exams at 20 min intervals for a total of 100 min were performed to assess the rabbits' neurological state. We concluded that the ILE did not interfere with diazepam's clinical effect but, although unlikely, the possibility of recurrence of a sedative effect should be considered.

Safety of intravenous iodinated contrast medium injection in rabbits undergoing conscious computed tomography

Background

Contrast media in CT is widely used in dogs and cats to provide superior tissue delineation and increase the diagnostic capabilities. These contrast-enhanced imaging techniques are gaining popularity in rabbits; published studies reporting the safety of doing so are lacking.

Methods

This retrospective observational study aimed to determine the incidence of adverse events following the intravenous administration of iodinated non-ionic contrast medium in 350 rabbits. The medical records of this subset of rabbits admitted between January 2009 and November 2018, that underwent CT examination and received intravenous contrast media, were evaluated.

Results

From the 350 rabbits, 342 rabbits were still alive 7 days after the scan. A total of eight rabbits died within 7 days of the scan, seven of which within the first 24 h. All deaths were presumed to be sequelae to the diseases they were being investigated for and not thought to be related to the administration of intravenous contrast medium.

Conclusions

The results indicated that the use of intravenous non-iodinated contrast medium was well tolerated and safe in rabbits undergoing conscious CT examination.

Retrospective analysis of risk factors, clinical features, and prognostic indicators for urolithiasis in guinea pigs: 158 cases (2009-2019)

OBJECTIVE

To investigate risk factors, clinical features, and prognostic indicators in guinea pigs with urolithiasis.

ANIMALS

158 guinea pigs with urolithiasis.

PROCEDURES

Medical records of an exotics animal specialty service were searched, identifying guinea pigs with urolithiasis. Signalment, clinical data, and outcomes were recorded. Variables of interest were analyzed for statistical associations with outcome.

RESULTS

Overall, 54.4% (86/158) of animals survived to discharge. Median survival time was 177 days. Females (53.2%; 84/158) were more common than males (46.8%; 74/158). Males were presented younger (mean age, 3.64 years) than females (4.41 years). In 81 of 154 (52.5%) cases, animals were presented with primary urinary concerns, while 73 (47.5%) presented for nonurinary primary concerns. Females more commonly presented with distal urinary tract urolithiasis (63/84; 75%) but fared better overall with a longer median survival time (1,149 days) than males (59 days). Surgical intervention was not a risk factor for nonsurvival; however, increased age (> 4.1 years), male sex, anorexia, weight loss, and lower rectal temperature (< 37.2 °C) on presentation were associated with nonsurvival. Reoccurrence was noted in 13.9% (22/158) of cases, at an average of 284 days.

CLINICAL RELEVANCE

Urolithiasis should always be considered a differential diagnosis for any unwell guinea pig. In particular, distal urinary tract urolithiasis should be considered in females. A poorer prognosis was associated with older, male guinea pigs, and those displaying anorexia, weight loss, and hypothermia. The need for surgical intervention should not confer a poorer outcome. Further studies are needed to determine specific risk factors and identify possible preventative measures.

The effect of blindfolding and swaddling on the stress response to handling in domestic rabbits

Stress during handling can negatively impact the welfare of an animal. Gradual habituation or systematic desensitisation can reduce this but is not always possible. Blindfolding has been shown to decrease stress indicators, including heart rate and struggling in cattle (Bos taurus), but has not been studied in domestic rabbits (Oryctolagus cuniculus). We surveyed 49 wildlife rescues, rehabilitators and veterinarians, and found that blindfolding and swaddling are widely used and believed to reduce stress and struggling in rabbits. However, these methods may simply preclude escape and result in sensitisation over repeated exposure. We next conducted a controlled trial investigating the effects of blindfolding and swaddling repeatedly over five days on behavioural and physiological indicators of stress in 40 domestic rabbits. Neither blindfolding nor swaddling had significant impacts on heart or respiratory rate, compared to a partial hood control treatment, which involved similar levels of manipulation, but without visual or movement restriction. Behavioural responses showed variable trends, eg rabbits were more likely to approach food after handling with swaddling. Baseline levels varied significantly between individuals, suggesting previous experience to be an important determinant. Heart rates were universally high, showing that individuals in this study were stressed by handling to such an extent, that overall, effects of both blindfolding and swaddling on physiological indicators of stress were minimal. We suggest that blindfolding and swaddling may be useful as means of limiting the procedure duration and risk of injury by reducing struggling, but this study provides no evidence that welfare is otherwise improved.

Effects of Tinidazole on Food Intake in Chinchillas (Chinchilla lanigera)

Tinidazole is a second-generation nitroimidazole compound that is used as an antimicrobial to treat anaerobic bacterialand protozoal infections in humans and, less frequently, in veterinary medicine. However, metronidazole, another secondgeneration nitroimidazole, is more commonly used. Nonetheless, tinidazole has proven to be a superior therapy for parasitic infections in humans, particularly in the treatment of giardiasis. Furthermore, in chinchillas, metronidazole has been shown to cause a clinically relevant reduction in food intake after oral administration at published dosages. This study's objective was to evaluate the effect of orally administered tinidazole on food intake in healthy chinchillas. In 2 randomized, placebocontrolled,blinded, crossover studies, tinidazole was evaluated at 2 single high doses (100 mg/kg and 200 mg/kg PO, n =9) and a repeated dosing schedule at a lower dose (20 mg/kg PO q12h for 10 doses, n = 12). Food intake was measured over24-h periods before and after drug administration. The single-dose treatment groups both displayed significantly reducedfood intake (200 mg/kg: -26 ± 21%; 100 mg/kg: -9 ± 21%, P < 0.01) as compared with the control group during the first 24 hafter drug administration. Food intake returned to pretreatment values within 4-5 d. Repeated administration at 20 mg/kg q12h was not associated with any significant changes in food intake. No other adverse effects were noted during this study. Tinidazole administration at single higher doses resulted in an acute self-limiting reduction in food intake. In comparison, repeated administration of lower doses (20 mg/kg PO q12h) had no significant effects on food intake in healthy chinchillas. Therefore, tinidazole may be a more suitable drug for treating Giardia and anaerobic bacterial infections in this species than the more commonly used metronidazole.

Comparison of 2 portable human glucometers for the measurement of blood glucose concentration in White New Zealand rabbits

We compared measurements of blood glucose concentrations in 30 healthy adult White New Zealand rabbits using 2 commercial portable glucometers (PGM1 and PGM2) and a laboratory chemical analyzer. Results were analyzed with Pearson correlation, Passing-Bablok regression analysis, Bland-Altman analysis, and a modified error grid. Measurements with PGM1 were significantly correlated (r = 0.37) with those obtained from the laboratory reference method (RM); Bland-Altman and Passing-Bablok analyses indicated no significant systematic or proportional differences (mean difference of -0.26, 95% CI of mean difference of -0.54 to 0.01, and LOA of -1.70 to 1.17); and error grid resulted in 100% of measurements in zone A. No significant correlation (r = -0.05) was detected between PGM2 and RM; Bland-Altman and Passing-Bablok analyses results indicated a mean difference of 2.14, 95% CI of mean difference of 1.67-2.60, and limit of agreement of -0.32 to 4.59, which overestimated blood glucose concentration, with 53% of glucose measurements in error grid zone A and 47% in zone B. PGM1 was considered accurate in normoglycemic rabbits, whereas the use of PGM2 could result in overestimations of glycemia.

Clinical and pathological findings for rabbits with dystocia: 10 cases (1996-2016)

OBJECTIVE

To characterize clinical and pathological findings of rabbits evaluated at a veterinary teaching hospital because of dystocia.

DESIGN

Retrospective case series.

ANIMALS

9 client-owned rabbits and 1 wild rabbit with signs of dystocia evaluated at a veterinary teaching hospital from 1996 through 2016.

PROCEDURES

Medical records of rabbits were reviewed to collect data on signalment; medical history; physical examination, laboratory, diagnostic imaging, and procedural findings; treatment; final diagnosis; and outcome. Data were summarized.

RESULTS

Dystocia in 7 rabbits was successfully managed through medical treatment, assisted vaginal delivery, or both (n = 6) or surgery alone (1); 3 rabbits were euthanized. Primiparous does, does ≤ 4 years old, and does of small breeds (< 2 kg [4.4 lb]) were most common. All client-owned rabbits had clinical signs of abnormal second-stage parturition, whereas the wild rabbit had only hemorrhagic vulvar discharge. Imaging was used to identify the number, size, and state of fetuses in most rabbits. Overall, 35 fetuses were accounted for, 25 of which were dead or later died. The cause of dystocia was determined for 8 rabbits and included fetal-maternal mismatch (n = 4), uterine inertia (2), fetal death or mummification (1), and stress-induced abortion (1).

CONCLUSIONS AND CLINICAL RELEVANCE

Obstructive dystocia from fetal macrosomia with or without secondary uterine inertia was the most common cause of dystocia in the evaluated rabbits. Although medical management was successful for many rabbits with dystocia in this study, surgery could still be required in other affected rabbits, particularly when fetal-maternal mismatch is involved.

Pharmacokinetics of hydromorphone hydrochloride after intravenous and intramuscular administration in guinea pigs (Cavia porcellus)

OBJECTIVE

To determine the pharmacokinetics of hydromorphone hydrochloride after IV and IM administration in guinea pigs (Cavia porcellus).

ANIMALS

8 healthy adult guinea pigs (4 sexually intact females and 4 sexually intact males).

PROCEDURES

In a crossover study, hydromorphone (0.3 mg/kg) was administered once IM (epaxial musculature) or IV (cephalic catheter) to each guinea pig at a 1-week interval (2 treatments/guinea pig). Blood samples were collected before and at predetermined intervals after drug administration via a vascular access port. Plasma hydromorphone concentrations were determined by liquid chromatography-tandem mass spectrometry. Noncompartmental analysis of data was used to calculate pharmacokinetic parameters.

RESULTS

Mean ± SD clearance and volume of distribution for hydromorphone administered IV were 52.8 ± 13.5 mL/min/kg and 2.39 ± 0.479 L/kg, respectively. Mean residence time determined for the IV and IM administration routes was 0.77 ± 0.14 hours and 0.99 ± 0.34 hours, respectively. The maximum observed plasma concentration following IM administration of hydromorphone was 171.9 ± 29.4 ng/mL. No sedative effects were observed after drug administration by either route.

CONCLUSIONS AND CLINICAL RELEVANCE

Pharmacokinetic data indicated that hydromorphone at a dose of 0.3 mg/kg may be administered IV every 2 to 3 hours or IM every 4 to 5 hours to maintain a target plasma concentration between 2 and 4 ng/mL in guinea pigs. Hydromorphone had high bioavailability after IM administration. Further research is necessary to evaluate the effects of other doses and administration routes and the analgesic effects of hydromorphone in guinea pigs.

Frequency of Owner-Reported Bacterial Infections in Pet Guinea Pigs

Domestic guinea pigs suffer morbidity and mortality due to a range of bacterial infections amongst other causes. Microorganisms such as Bordetella bronchiseptica and Streptococcus pneumoniae are commonly implicated in respiratory disease; however, there is a lack of research surrounding the prevalence of these bacterial infections. The aim of this study was to investigate the frequency with which owners reported bacterial infections in pet guinea pigs and to assess owner knowledge of correct husbandry practices to inform prevention of the development of bacterial infections. An online questionnaire, consisting of 30 questions was promoted to guinea pig owners. Of all respondents (n = 524), 39.39% reported that their guinea pig(s) had been clinically diagnosed with a bacterial infection, with upper respiratory tract infections the most commonly reported (46.95%), followed by urinary tract (15.49%) and then gastrointestinal infections (11.73%). Owners demonstrated knowledge of correct husbandry practices and there was no significant effect (p = 0.475) of owner knowledge on having owned a guinea pig with a bacterial infection. Bacterial infections may be more common in guinea pigs than was previously thought. Further research is required to understand why bacterial infections are common in pet guinea pigs and to help owners to prevent and recognize these infections.

Ambulatory Emergency Medicine

While practicing exotic animal medicine as an ambulatory practitioner, veterinarians need to be prepared for the inevitable emergency call. Emergencies in exotic animal medicine come in all shapes and sizes and the veterinarian must be prepared for a variety of situations. With the proper training, equipment, and managing client expectations, an ambulatory exotics animal practitioner can successfully address emergencies. This article provides a brief overview in managing emergency cases in an ambulatory exotics animal practice.