Companion Rabbits Research Articles

Dental disease is a common issue in companion rabbits

There are approximately 1.1 million pet rabbits in the UK. Rabbit teeth continue to grow throughout their lifetime, and dental problems are not uncommon. New research from the Royal Veterinary College has identified that one in seven companion rabbits are experiencing dental disease. There are various risk factors which can contribute to dental disease, but all companion rabbits should have regular dental check-ups to maintain good dental health.

Rabbit intakes and predictors of their length of stay in animal shelters in British Columbia, Canada.

Domestic rabbits (Oryctolagus cuniculus) are the fourth most common species admitted to the British Columbia Society for the Prevention of Cruelty to Animals (BC SPCA) shelter system. However, shelter data analysis has largely focused on cats and dogs and little is known about the population dynamics of rabbits in shelters. We analyzed five years of rabbit records (n = 1567) at the BC SPCA to identify trends in intake and predictors of length of stay (LOS) of rabbits. The majority of rabbits were surrendered by their owners (40.2%), with most rabbits being surrendered for human-related reasons (96.9%). Overall, rabbit intakes decreased over the study period. When analyzing by month of intake, rabbit intakes were found to be the highest in May. Most rabbits in our data were adults (46.7%), non-brachycephalic (66.7%), erect-eared (82.5%), short-furred (76.2%), and subsequently adopted (80.3%). The median LOS of rabbits was 29 days, highlighting the pressing need to improve their time to adoption. A linear model was constructed to identify predictors of LOS of adopted rabbits (n = 1203) and revealed that intake year, intake month, source of intake, age, cephalic type, and breed size significantly predicted time to adoption for rabbits (F(37, 1165) = 7.95, p < 2.2e-16, adjusted R2 = 0.18). These findings help characterize shelter population dynamics for rabbits, shed light on the challenges associated with unwanted rabbits, and offer a foundation for animal shelters to design programs and marketing strategies tailored to reduce LOS of rabbits with particular characteristics. Shelter rabbits represent an understudied population and our study highlights the importance of further research in companion rabbits.

Dental disease in companion rabbits under UK primary veterinary care: Frequency and risk factors.

Some prior evidence has suggested that lop-eared rabbits and those with brachycephalic skull conformations have a higher dental disease risk. This retrospective cohort study reports the frequency and conformational risk factors for primary-care veterinary diagnosis with dental disease in companion rabbits in the UK. Anonymised VetCompass clinical records were manually reviewed to confirm dental disease cases. Risk factor analysis used multivariable binary logistic regression modelling. From 161,979 rabbits under primary veterinary care in 2019, the 1-year period prevalence of overall dental disease was 15.36% (95% confidence interval [CI]: 14.78-15.96). The prevalence of dental disease affecting incisors was 3.14% (95% CI: 2.87-3.44), and for cheek teeth it was 13.72% (95% CI: 13.17-14.29). Neither lop-eared conformation nor brachycephalic skull conformation was significantly associated with increased odds of dental disease. Dental disease odds increased as age increased and decreased as bodyweight increased. This study retrospectively accessed clinical records, so breed names may sometimes be imprecise. The high overall prevalence of dental disease represents a major welfare concern for all companion rabbits, regardless of conformation. This information can be used to encourage regular routine dental assessment of rabbits of all conformations to promote earlier diagnosis, paying particular attention to older rabbits and those with low bodyweight.

Does a stronger bond with pet rabbits equate to better husbandry conditions for them?

Rabbits are becoming one of the most popular pets in western countries, including the Czech Republic. Until now, the welfare-husbandry conditions of rabbits in correlation with owner attachment to the rabbit has never been investigated. The aim of this study was to investigate whether the bond with a rabbit and selected factors, such as ownership of a dog and/or cat, the time spent with the rabbit, and the age of any children living in the household, have an impact on a pet rabbit’s husbandry conditions. Data was gathered on the basis of a questionnaire survey conducted among pet rabbit owners in the Czech Republic. In total, 1651 completed questionnaires were collected through various channels, namely veterinary surgeries, pet shops, breeders, and social media. The questions covered demographics, living conditions, the presence of children and/or other pets, and the strength of the bond. We found that living with a child/children under 12 years of age, owning a dog and a cat, and spending less time with the rabbit were associated with a decreased bond between the owner and the rabbit. It was also found that decreased time spent with the rabbit is associated with decreased animal husbandry conditions. However, only a weak association was found between the bond of the owners to their rabbit and its welfare-husbandry conditions. Overall, the most alarming finding was that over 80% of companion rabbits in Czech Republic are kept in isolation. In conclusion, the amount of time owners spend with their rabbit appears to be a suitable parameter for determining the strength of the bond attachment and husbandry conditions of the rabbit. There were minimal differences between the strength of the bond and the breeding status of the rabbit if there was a child and/or other pets such as a dog and/or cat in the household. The role of rabbits has changed recently, and it is therefore necessary to conduct comprehensive research into rabbit welfare.

Understanding rabbit owners' willingness to engage in disease prevention behaviors.

Rabbit hemorrhagic disease virus 2 (RHDV2) is a fatal, highly contagious pathogen that infects wild and domestic lagomorphs (rabbits and hares). RHDV2 is an important cause of disease in pet and companion rabbits, has resulted in economic losses for the commercial rabbit industry, and has caused declines of wild lagomorph populations. It is essential for domestic rabbit owners to engage in appropriate actions (e.g., using effective disinfectants, creating secure barriers between domestic and wild rabbits) to protect the health and welfare of their rabbits and reduce the risk of human-mediated spread of RHDV2. Thus, we investigated rabbit owners' stated willingness to engage in nine commonly recommended biosecurity practices and their support for seven potential government-implemented management actions. We administered an online survey to 1790 rabbit owners in the United States between April and August 2021. Respondents were likely to engage in all biosecurity measures and were supportive of most management actions that could be implemented by government agencies. Respondents' willingness to engage in and support biosecurity measures was positively correlated with their perceptions of the importance of biosecurity, risk perceptions pertaining to the impact of RHDV2 on lagomorphs and rabbit-related industries, knowledge of RHDV2, and trust in government to manage RHDV2. Respondents' motivations for owning rabbits, husbandry behaviors, and demographic characteristics also influenced their willingness to engage in or support biosecurity measures. Engaging domestic rabbit owners in collaborative biosecurity measures is critical for protecting domestic rabbit health and preventing potential spillover between domestic and free-roaming lagomorphs, as there are still many uncertainties about how RHDV2 is spreading across the United States and the world. Implementing outreach strategies that communicate the importance and effectiveness of biosecurity practices in protecting rabbit welfare, rabbit-related activities, and wild lagomorph populations may increase the likelihood of rabbit owners adopting biosecurity measures.

Companion Rabbits: A Case Study Concerning Sudden-Onset Inappropriate Urination

Abstract Despite their domestication some 1500 years ago, the behavioural repertoire of companion rabbits barely differs from that of wild rabbits. When presented with a companion rabbit behaviour issue, it is, therefore, necessary to consider their management in relation to the habitat, biology and behaviour of wild rabbits. Health factors may also be implicated; although as a prey species, rabbits naturally hide signs of disease or injury. This can complicate a health diagnosis. This case study concerns an elderly spayed female indoor rabbit, Meg, who shared a positive relationship with her caregiver. Meg had experienced degenerative musculoskeletal changes for which treatment was on-going, and had previously had treatment for dental spurs and pododermatitis. Prior to Meg’s behaviour assessment, her caregiver sought advice from their Veterinary Surgeon due to Meg’s recent-onset urination outside her litter-trays overnight and occasionally during the day. The Veterinary Surgeon referred Meg to a Certificated Clinical Animal Behaviourist (CCAB) for a behaviour assessment which was conducted remotely using a questionnaire, home-layout diagram, photographs, video-footage and video-conference software. A behaviour diagnosis was made regarding Meg’s emotional and motivational state, and additional stressors were identified. Due to likely health and behaviour overlap, the CCAB further liaised with the referring Veterinary Surgeon. A treatment plan was devised, which Meg’s caregiver diligently implemented. Meg responded well to her treatment plan and over the course of 3 weeks, inappropriate urination ceased. In turn, the welfare of Meg and her caregiver significantly improved. Information © The Author 2023

Perceptions of the rabbit as a low investment 'starter pet' lead to negative impacts on its welfare: Results of two Danish surveys.

Concerns over compromised companion rabbit (Oryctolagus cuniculus domesticus) welfare are widespread. The welfare problems have been linked to the perception of rabbits as low investment 'children's pets.' To test this hypothesis and investigate the current conditions for rabbits, data were gathered from two surveys in 2021: a nationally representative survey of Danish companion animal owners (Survey I) and a detailed social media-based survey of Danish rabbit owners (Survey II). Using logistic regression, three owner-related variables (whether a child/adult was responsible for care of the rabbit, owner-opinion on rabbits' suitability as 'starter pets' and willingness-to-pay [WTP] for veterinary treatment) were employed to investigate the effect of rabbit status on owner-provision of selected husbandry conditions. The 76 (Survey I) and 4,335 (Survey II) responses suggested that most rabbits are acquired for children and are solitarily housed, and that many are kept in cages of an unsuitable size and not checked daily. Owners who perceived rabbits as 'starter pets' and with lower WTP were more likely to house rabbits in restricted space and to not provide continuous gnawing opportunities, ad libitum hay or routine healthcare. A child fulfilling the role of the rabbit's main caretaker was also associated with inadequate housing type and fewer gnawing opportunities. Thus, many rabbits live in unsuitable conditions, and owners who perceive rabbits as low investment 'children's pets' are more likely to not provide recommended resources. Changing owners' perceptions of rabbits and promoting suitable husbandry through official education programmes and minimum requirements is important if there are to be improvements made to rabbit welfare.

Death in four RHDV2-vaccinated pet rabbits due to rabbit haemorrhagic disease virus 2 (RHDV2).

To create awareness of single RHDV2 infections and cases of death despite immunisation with RHDV2-specific vaccine. Retrospective case series of four companion rabbits. Patient signalment, vaccination history, pathology and molecular examinations were obtained from the medical records. The animals died peracutely or with nonspecific symptoms like apathy and inappetence. Pathological examination indicated and molecular biological findings confirmed RHDV2 infection in four animals. Several partner animals died at the same time under the same circumstances. This is the first report of fatalities in RHDV2-vaccinated companion rabbits due to rabbit haemorrhagic disease virus 2 infection with documented case and vaccination history. Veterinarians should be aware of possible single fatal RHDV2 infections despite vaccination, should initiate the clarification of suspected cases and inform vaccine manufacturers and competent authorities.

Pododermatitis en conejos: Reporte de caso

Pododermatitis is a frequent disease found in several species to which it causes foot lesions and limb deformities depending on the degree of the lesion. In rabbits the disease presents a multifactorial character but the most common is the development due to excess weight. In this disease it is possible to observe the presence of ulcers with Osteomyelitis development triggered by the action of bacteria. The most common bacteria are Staplylococcus aureus and Pasteurella multocida. In this report it was possible to observe the bacterium Acinetobacter baumannii which is very found in the human clinic laboratory. During the work, comparisons were made between treatments developed by different authors. The main objective of this study is to report a clinical case involving ulcerative pododermatitis in companion rabbit associated to myiasis and relapsing inflammatory otitis. In addition, a discourse will be developed on the treatments developed demonstrating the real importance of the need of diagnosis by cytology and antibiogram to identify the pathogen present in order to avoid excessive treatment and bacterial resistance.

Efficacy of Fluralaner in the Treatment of Sarcoptic Mange (Sarcoptes scabiei) in 12 Pet Rabbits

Sarcoptes scabiei var. cuniculi are cutaneous mites of companion rabbits. In rabbits, sarcoptic mange is characterized by intense pruritus, alopecia, erythema, scales, and crusts around the head, neck, trunk, feet, and genitals. The goal of this study was to evaluate the effectiveness of oral fluralaner in pet rabbits naturally infested by S scabiei var. cuniculi. Twelve privately owned pet rabbits with a definitive diagnosis of sarcoptic mange were included in the study if they had compatible clinical signs and positive superficial skin scrapings for S scabiei. Clinical and parasitological evaluations were performed on days 0, 7, 14, 21, 30, 60, and 90 after receiving a single oral dose of 25 mg/kg of fluralaner. On day 7, 5 of 12 rabbits had positive skin scrapings, while 8 of 12 had clinical signs (alopecia and erythema) still present. By day 14 none of the rabbits had positive skin scrapings and only 1 of 12 had persistent clinical signs. By day 21 none of the rabbit had positive skin scrapings nor had clinical signs. A reoccurrence of the clinical signs or positive skin scrapings was not observed for the duration of the study (day 90). A single oral dose of fluralaner was effective for the treatment of naturally occurring sarcoptic mange in rabbits over a 90-day period.

The effects of single-dose administration of two topical antiglaucoma medications, 0.005% latanoprost and 0.125% demecarium bromide, on intraocular pressure and iridocorneal angle parameters in nonglaucomatous companion rabbits

Glaucoma is a blinding, painful disease in mammals, including rabbits. This study aimed to determine effects on intraocular pressure (IOP) and iridocorneal angle (ICA) morphology of two antiglaucoma therapies, 0.005% latanoprost (latanoprost) and 0.125% demecarium bromide (demecarium) in companion rabbits. Twenty healthy rabbits of varying breeds and ages were used. All animals received a complete ophthalmic examination including rebound tonometry and gonioscopy, and ICA imaging using spectral domain optical coherence tomography (SD-OCT), high-resolution ultrasound, and Scheimpflug imaging (Pentacam® HR). Angle opening distance (AOD) and angle recess area (ARA) were measured. Demecarium was applied to one eye and latanoprost to the contralateral eye. Each eye was re-evaluated 1 hour later with tonometry, imaging, and gonioscopy. Pre- and post-treatment groups were compared with a Wilcoxon signed-ranked test for IOP, ARA, AOD, and gonioscopy score. Estimates of treatment effects were performed to identify clinically significant differences of demecarium and latanoprost on ICA parameters. Latanoprost caused a significant increase in gonioscopy score, ARA, and AOD when measured via SD-OCT whereas demecarium caused a significant decrease in gonioscopy score, ARA, and AOD when measured via SD-OCT and Pentacam® HR. Demecarium significantly increased IOP whereas latanoprost had no effect on IOP. Based on the increased ICA parameters in normal companion rabbits, latanoprost can be considered as a glaucoma medication in rabbits. Demecarium increased IOP and decreased ICA parameters; therefore, its use in rabbits is not recommended.

Parotid salivary mucocele in a companion rabbit (Oryctolagus cuniculus): a report on the clinical and laboratory characteristics and surgical treatment ˗ case report

ABSTRACT The present report aimed to describe the main characteristics of the parotid salivary mucocele in an adult male rabbit, which presented with a painless fluctuating mass with fluid content. Owing to the need for repeated fluid drainage, surgical excision was the chosen mode of treatment. Preoperative evaluation included radiography and blood analysis. The patient underwent surgical excision of the affected gland. Inhalation anesthesia was maintained by means of isoflurane and the cardio-respiratory parameters were monitored throughout the surgery. A bipolar electrocautery was used to assist in the incision and polyglactin 910 and nylon were the suture materials used in the wound closure technique. Post-operative medications included analgesics, anti-inflammatory agents and antibiotics. Histopathology of the excised glandular tissue revealed a mixed inflammatory infiltrate, fibroblasts, hemorrhage and hyperemia. The observations in this case suggest that surgical excision of the affected gland is the treatment of choice for the management of mucocele in companion rabbits, which has already been identified for other animals. Periodic acid-reactive Schiff staining confirmed the diagnosis of salivary mucocele. The complementary investigations helped to rule out the differential diagnosis and indicated a favorable prognosis, in view of the fact that the case was successfully resolved without complications or recurrence.

Patterns of mandibular asymmetries in two types of companion rabbits.

Developmental instability hypothesis suggests that asymmetric variation can partially reflect the body's inability to buffer environmental and/or genetic perturbations. Fluctuating asymmetry (FA), that is random differences between the left and right sides of body features that are symmetric at the population level, can assess this approach. Another kind of asymmetry is directional asymmetry (DA) which appears when the left and right sides differ consistently from each other. Extreme selection for morphological traits, as appear in some companion rabbits selected for a paedomorphic (dwarf rabbits) or gerontomorphic (belier rabbits) appearance, may cause abnormal functional conditions, which in turn could be expressed as significative degrees of asymmetries. To study these phenomena, we analysed 62 mandibles of companion rabbits (20 beliers and 42 dwarfs) by means of geometric morphometric methods and quantified their size and shape asymmetric variation (both FA and DA) using 18 landmarks on the lateral side. FA was present in both types but in different degrees, being higher among dwarfs. It is considered that this type is subject to deeper changes than among beliers, and therefore, there is higher pressure on the phenotype. This observation could be assumed to be an adaptive response, coming out as FA. The presence of DA was significative and similar for two types. This likely indicates common masticatory lateralization, a pattern that has been detected in other domestic mammals. The methodological framework presented in this study can be valuable for future works focused on genetically and/or environmentally related form study in pets.

A double-blind, placebo-controlled trial investigating the value of Pet Remedy in ameliorating fear of handling of companion rabbits

Rabbits are popular companion animals. There are numerous welfare issues affecting the majority of the population, including the fact that most rabbits are fearful when handled. Pet Remedy ™ (Unex Designs) is an herbal product containing valerian, marketed as a natural calming aid. Its efficacy for domestic rabbits is previously untested. We describe a randomized, double-blind, placebo-controlled trial into the effectiveness of Pet Remedy. Fifty rabbits underwent a baseline test followed by both a placebo and a Pet Remedy treatment. We measured rabbit’s behavior by a novel arena test, responses to the experimenter when in the home enclosure and when being handled, and heart and respiratory rates during handling. Repeated measures analysis of variance tested differences between treatments, taking into account rabbits’ individual baselines. Exposure to Pet Remedy was associated with a significant decrease in heart rate during handling (F(1,42) = 4.41, P = 0.042) and a significant increase in the number of positive behaviors observed in the novel arena (F(1,47) = 4.52, P = 0.039). Other variables which may have been predicted to change were unaffected. Rearing in the novel arena increased with day (F(1,45) = 6.91, P = 0.012). Significant individual variation occurred throughout, and heart rates were universally high suggesting that handling is generally an aversion to rabbits. The results suggest that Pet Remedy may have potential value for rabbits during periods of acute stress, slowing heart rate, and allowing the performance of more positive, relaxed behaviors. It may be useful during veterinary visits and initial handling. However, given the high levels of physiological and behavioral stress exhibited by rabbits, optimal handling and appropriate habituation and desensitization and counter-conditioning protocols should also be simultaneously implemented.

First insight into Encephalitozoon cuniculi infection in laboratory and pet rabbits in Iran

Encephalitozoon cuniculi infects a wide variety of domestic and wild mammalian species including humans. Although the infection status has been studied in laboratory and pet rabbits worldwide, there is shortage of information regarding the disease in Iran. In the present study, the occurrence of infection in brains of 117 asymptomatic rabbits from six breeding and experimental units with highest population of rabbit colonies in the country (n = 60) as well as pet rabbits of pet stores in two cities (n = 57) were examined by nested-PCR. Histological sections of brains and kidneys were also studied by light microscopy. PCR results revealed that 3.3% of laboratory rabbits (2/60) and 59.6% of pet rabbits (34/57) harboured E. cuniculi in their brains. Histopathology on the other hand showed spores of the parasite in kidney and brain of one and kidney of another pet rabbit. As encephalitozoonosis may interfere with results of experiments performed on laboratory rabbits, routine screenings for identification and culling of infected animals is recommended. Furthermore, infected companion rabbits can transmit E. cuniculi to people in close contact with them, therefore, improving public knowledge of this zoonotic infection is suggested.

Iridocorneal angle assessment of companion rabbits using gonioscopy, spectral-domain optical coherence tomography (Optovue iVue® ), high-resolution ultrasound, and Pentacam® HR imaging.

Iridocorneal angle (ICA) narrowing is a known risk factor for primary glaucoma in multiple species, but has not been described in companion rabbits. This study aimed to develop an ICA grading scheme for companion rabbits to enable early glaucoma predisposition diagnosis. Twenty healthy rabbits of varying breeds and ages. Rabbits received complete ophthalmic examinations, including gonioscopy, and imaging of the ICA using spectral-domain optical coherence tomography (SD-OCT), Scheimpflug imaging (Pentacam® HR), and high-resolution ultrasound (HRUS). Angle opening distance (AOD) and angle recess area (ARA) of the ICA were measured and assessed for agreement using a Bland-Altman analysis. A five-stage gonioscopy grading scheme was created, and Spearman-rank test assessed for correlation between gonioscopy grades and ICA measurements. Differences among age and sex were analyzed with a nonparametric ANOVA and Wilcoxon rank-sum test, respectively. Analysis revealed AOD medians of 0.28mm for SD-OCT [95% CI: 0.24-0.31], 0.20mm for Pentacam® HR [95% CI: 0.18-0.21], and 0.25mm for HRUS [95% CI: 0.22-0.28]. The median ARA was 0.14mm2 for SD-OCT [95% CI: 0.117-0.163], 0.09mm2 for Pentacam® HR [95% CI: 0.082-0.100], and 0.06mm2 for HRUS [95% CI: 0.046-0.054]. The association between gonioscopy grade and SD-OCT ARA was significant (P<0.05), and there was a significant difference (P<0.001) between imaging modalities for both ARA and AOD. Gonioscopy grade correlated well with SD-OCT ARA. Therefore, SD-OCT is recommended as a noncontact method for evaluating companion rabbit ICA. Each imaging device should not be used interchangeably for ICA evaluation.

Hypercholesterolemia and hypertriglyceridemia as biochemical markers of disease in companion rabbits.

Inflammation has important effects on lipid metabolism, but the relationship between hyperlipidemia, inflammation, and disease remains unknown in rabbits. While rabbits are sensitive to dietary hypercholesterolemia, the etiology of hyperlipidemia when fed non-atherogenic diets is uncertain. This study aimed to determine the association between hypercholesterolemia and patient characteristics, diseases, and select CBC and biochemistry analytes in rabbits, and to measure plasma lipoprotein lipid fractions in rabbits with inflammatory and other diseases. Complete blood count and plasma biochemistry data, including total cholesterol concentrations, were evaluated in 531 companion rabbits. Lipoprotein cholesterol fractions (non-high-density lipoprotein cholesterol [non-HDLc] and high-density lipoprotein [HDLc]) and triglycerides were measured using a colorimetric enzymatic assay in archived plasma from a subset of 267 rabbits. Rabbits were categorized by age, sex, spay/neuter status, breed, diet status (fed atherogenic dietary components or not), the organ system affected by disease, and the pathologic process. Cholesterol was associated with fibrinogen (P=0.01), globulins (P<0.01), and heterophil (P<0.01) concentrations. Adjusting for diet, rabbits with severe infection or sepsis (odds ratio [OR]=13.25, 95% CI=5.83-30.12), renal failure (OR=14.42, 95% CI=5.69-36.54), and hepatopathy (OR=8.55, 95% CI=3.55-20.62) had increased risks of hypercholesterolemia. Increased non-HDLc and triglyceride concentrations were also associated with these three disease states (P<0.05). Hyperlipidemia is associated with biochemical and CBC markers of inflammation, and with severe infection or sepsis, renal failure, and hepatopathy. Independent of diet, increased cholesterol, non-HDLc, and triglycerides are indicators of disease in companion rabbits.

Oda A, Messenger KM, Carbajal L, et al. Pharmacokinetics and pharmacodynamic effects in koi carp (Cyprinus carpio) following immersion in propofol. Vet Anaesth Analg 45:529-538, 2018.

This report describes post-traumatic ocular lymphoma in 3 companion rabbits; 2 rabbits with unilateral disease and 1 with bilateral disease. Historical findings suggestive of a traumatic event included either external unilateral ocular trauma or bilateral phacoemulsification. Severe corneal changes, presence of an anterior chamber mass(es), low intraocular pressures, and ocular discomfort were noted on ophthalmic examinations. All eyes were treated for variable courses with standard ophthalmic topical medications (antibiotic, anti-inflammatories, and steroid) and systemic anti-inflammatories. Based upon progression of disease, all affected eyes were ultimately enucleated; lenticular capsular rupture and a round cell neoplasm effacing normal structures with variable mitotic indices were noted on histopathology. Neoplastic lymphocytes strongly expressed CD79a via immunohistochemistry and lacked expression for CD3, indicating B lymphocyte lineage and not of T cell lineage. A single animal had evidence of local metastasis to a regional lymph node. Post-traumatic sarcomas have been reported in this species previously, however, these cases are the first reports of this novel round cell variant, named post-traumatic ocular lymphoma due to the B cell lineage confirmed through immunohistochemistry. Clinicians should be aware of this clinical presentation and the possibility of metastasis when evaluating ocular pathology in this species.

Human-directed aggression in rabbits: a behavioural case study

This behavioural case study discusses human-directed aggression in a companion rabbit. It highlights how, when assessing and treating problem behaviour, the natural habitat, biology and behaviour of wild rabbits must be considered in relation to companion rabbit management.

Diferente desarrollo cefálico según tipo de conejo

Como alometría se entiende el crecimiento relativo de una estructura biológica respecto a otra(s) o al organismo total y da cuenta de los cambios de conformación que derivan de la modificación de tamaño. Un caso particular es cuando la velocidad de crecimiento es la misma entre los caracteres en estudio, lo cual recibe el nombre de isometría. A fin de estudiar este fenómeno en el conejo doméstico, se colectó un total de 71 cadáveres frescos de conejos, de diferente edad, correspondientes a animales destetados, y se obtuvo por descarnado el cráneo de cada uno. De ellos, 59 correspondían al tipo de compañía (tipos “toys” y “beliers”) y 12 al tipo carnicero (californiano/neozelandés). Se captó una imagen digital, en la cara lateral, de cada cráneo, sobre la que posteriormente se situaron 12 hitos anatómicos, analizados mediante métodos de morfometría geométrica. Los conejos de carne presentaron un comportamiento claramente isométrico, mientras que los de compañía, y a pesar de que muchos ya eran adultos, este comportamiento era alométrico. Nos encontramos, pues, ante un caso de gerontomorfia en los conejos de carne —un desarrollo precoz— y una pedomorfia en los de compañía —un retardo en su crecimiento, puesto que, aunque adultos, siguen presentando una cara corta y plana, y un cráneo proporcionalmente grande, caracteres típicamente juveniles—. Para los primeros un desarrollo lo más precoz posible y para los segundos una retención de los caracteres juveniles; en ambos tipos, ejemplo de heterocronías de desarrollo.