Rabbit Breeding Research Articles

The efficacy of crossbreeding on reproductive and productive performance in New Zealand White and Flemish Giant rabbits

Crossbreeding is a well-established practice in livestock production aimed at improving reproductive and productive traits. This study evaluated the effects of crossbreeding on rabbits, focusing on comparisons between purebred Flemish Giant (n = 10), New Zealand White (n = 23), and their crossbred offspring (n = 27). Various parameters, including litter size, body weight, growth rate, and mortality, were assessed. The results demonstrated that crossbred rabbits presented a 15% faster growth rate than purebred rabbits, along with the lowest mortality rate and highest total meat output. This phenomenon, attributed to hybrid vigour, effectively blends the large frame of the Flemish Giant with the good litter size of the New Zealand White. Furthermore, statistical analyses, including ANOVA and Tukey‒Kramer’s honestly significant test, confirmed the significant effects of breed class on productivity, body weight, and carcass yield. Growth curves estimated using the Gompertz model highlighted the superior performance of crossbred rabbits under semiarid conditions. Notably, crossbreeding resulted in offspring with the highest dressing percentage and overall improved performance, offering potential advantages for rabbit producers worldwide.

The influence of drugs containing gluconolactone on the morphological parameters of the blood of rabbits

The work is devoted to the issues of using polyhydroxy acids in rabbit breeding. Antioxidants are extremely important compounds for living organisms. The authors considered the effect of gluconolactone used in the animal diet on the metabolic processes and physiological indicators of life activity of rabbits. Based on the studies (using gluconolactone as an example), the advisability of including supplements containing polyhydroxy acids in the rabbit diet is shown. Polyhydroxy acids, which are antioxidants, when regularly introduced with feed, help to increase the overall resistance of the body, stimulate the growth and healthy development of animals, which in turn leads to obtaining high-quality agricultural products. Rabbits, like other animals, can obtain antioxidants from plant foods, but their concentration may be insufficient for full protection against oxidative stress. To stabilize feed rations, various biologically active additives are used, which make it possible to increase the efficiency of animal rearing and improve productivity indicators. Thus, polyhydroxy acids, in particular gluconolactone, are well suited for sensitive animals that require the utmost care and gentle rearing.

GROWTH PERFORMANCE AND SEMEN CHARACTERISTICS OF MONGREL RABBIT BUCKS FED DIETARY LEVELS OF GARLIC (ALLUM SATIVUM) MEAL

This study was designed to evaluate the effect of garlic meal supplementation on growth performance and semen characteristics in rabbit bucks. Twenty-four (24) mixed breed rabbit bucks were used for this study. The bucks were allowed to acclimatize for two weeks before the commencement of the study, during this period, they were fed formulated diet and Calopogonium ad-libitum. Feed and clean drinking water were offered ad libitum to the experimental animals. Four different experimental diets were formulated with varying levels of 0.00, 0.50, 1.00 and 1.50% garlic meal as supplement and were coded as T1, T2, T3 and T4 respectively, with as control. The 24 bucks were weighed and randomly allotted into the four experimental treatments and replicated thrice with two rabbit bucks per replicate in a complete randomized design (CRD) for a period of 8 weeks. At the end of the feeding period, semen collection was done using a specially designed artificial vagina for rabbits. The data obtained were subjected to one-way analysis of variance (ANOVA) procedure using IBM Statistical Package for Social Science (SPSS) version 21. The result showed that garlic meal had significant effect (P<0.05) on final weight, total and daily feed intake. Garlic significantly influenced (p<0.05) sperm volume, motility, concentration and total cells per ejaculate however, did not affect sperm morphology. In conclusion, garlic meal supplementation at 1.0% (10g/kg) can improve some growth and seminal parameters in male rabbits.

Comparative analysis of meat quality of Laiwu black, Minxinan black and Hyla rabbits

Abstract. The meat rabbit industry in China relies on foreign breeds and synthetic lines; the development of superior domestic breeds has not yet been fully realised. We compared the meat quality of two Chinese local breeds of black rabbits (Laiwu black and Minxinan black) and Hyla commercial rabbits, to provide a reference for the utilisation of meat rabbit breeds. In the present study, 35 d old Laiwu black rabbits, Minxinan black rabbits, and Hyla rabbits (20 rabbits each) were selected and reared under identical feeding and management conditions for 7 weeks, after which 10 randomly selected rabbits from each group were slaughtered for the analysis of meat quality. The a∗ (redness) value of the two local breeds was significantly higher than that of Hyla rabbits (p<0.01). The shearing force and drip loss of Laiwu black rabbits were significantly lower than those of the other groups (p<0.05). The two local breeds exhibited significantly higher myoglobin levels than Hyla rabbits (p<0.01), while melanin was highest in the meat of Minxinan black rabbits. The essential amino acids (valine, isoleucine, leucine and lysine) were significantly lower in Minxinan black rabbits than in the other groups (p<0.05). Aldehyde (heptanal, octanal) contents in Minxinan black meat were significantly higher than those of the other groups (p<0.01); however, nucleotide (guanine, adenine) contents were significantly lower (p<0.01). Unsaturated fatty acids (oleic, linoleic, α-linolenic) were significantly higher in the meat of Laiwu black rabbits than in those of the other groups (p<0.05). Both Laiwu black and Minxinan black rabbits have certain advantages in terms of nutritional indicators while also having good meat colour and flavour. The results of this study provide a theoretical reference for the research and development of meat rabbit breeds.

Meta-analysis of genetic parameters for economic traits in rabbit using a random-effects model

The genetic improvement of rabbits helps increase their productivity and, consequently, increase the supply of animal protein for human consumption. The aim of this study was to perform a meta-analysis of genetic parameters (heritability and genetic correlation) for litter size at birth, litter weight at birth, litter size at weaning, litter weight at weaning and slaughter weight in rabbits. The final dataset contained 147 estimates of heritability and 32 estimates of genetic correlation across 34 articles published between 1992 and 2022. A random-effects model was used and the heterogeneity of estimates was assessed using Q and I2 statistics. Heritability estimates were of low magnitude for all traits, ranging from 0.09 to 0.18. The lowest heritability estimate was observed for litter size at weaning and the highest for slaughter weight. Most genetic correlations between traits were positive and moderate, ranging from 0.44 to 0.60. Significant heterogeneity among studies justified the use of random-effects models. The meta-analysis study provided reliable genetic parameter estimates and these results can support the development of rabbit breeding programmes..

A Case of Amami Rabbit Breeding in School of Yamato Village, Amami Oshima

A Case of Amami Rabbit Breeding in School of Yamato Village, Amami Oshima

Pedigree-Based Description of Danubia Alba Rabbit Breed Lines.

The diversity of livestock animal breeds is an integral part of global biodiversity and requires careful management for sustainability and future availability. Avoiding inbreeding is a crucial aspect of mating of breeding animals. Our aims were to describe the quality of the pedigree, generation interval, gene origin, inbreeding, and effective population size of Danubia Alba rabbit lines. Line "D" is the maternal, whereas lines "C" and "X" are used as the paternal lines. The pedigree information was followed back from the actual breeding rabbits up to the founder animals. The rabbits having offspring in 2023 were chosen as reference populations for each line. The complete generation equivalent (GenCom) was 17.68 for line "C", 18.32 for line "D", and 17.49 for line "X", respectively. The maximum number of generations (GenMax) was above 30 for each line. The estimated bottleneck effect is mostly the result of selection and not a real genetic loss. The Wright inbreeding coefficient (F_Wright) was the highest for the "X" line rabbits, whereas it was the lowest for the line "D". Kalinowski's decomposition of inbreeding showed that it originated mostly from the past; the current fixation of alleles was quite similar for the line "C" and "D". Based on the predicted effective population sizes, it seems that there is no problem in maintaining of Danubia Alba lines.

IMPLEMENTASI PERANCANGAN INTEGRASI SWOT BALANCED SCORECARD DALAM PENILAIAN KINERJA BISNIS PAKAN KELINCI PADA RABBIT BROTHERS DI KABUPATEN BANDUNG

Rabbit Brothers is one of the rabbit breeders established in 2017 located in West Java, West Bandung Regency. Rabbit Brothers rabbit feed sales in 2023 fluctuated. The tighter the competition, the company needs to determine strategies in business management to determine the company's current performance. The purpose of this study is to describe the strategy based on SWOT analysis, design a Rabbit Brothers rabbit feed strategy map based on SWOT Balanced Scorecard integration, performance measurement and performance assessment of Rabbit Brothers rabbit feed based on SWOT Balanced Scorecard integration, and improve Rabbit Brothers rabbit feed business performance based on SWOT Balanced Scorecard integration. The methods in this research are SWOT Analysis, Balanced Scorecard, Analytical Hierarchy Process Software Expert Choice, and Key Performance Indicator Lead Indicator. Rabbit Brothers rabbit feed strategy and strategy map, one of which is increasing profits, Rabbit Brothers rabbit feed performance is 93.04%, meaning that the company's performance is in a very healthy condition with the category (AAA). The performance of the four performance perspectives that are not optimal is improved on strategic initiatives, one of which is the content creation program.

Biostimulation methods based on chemical communication improve semen quality in male breeder rabbits

Biostimulation aims to optimize reproductive parameters as part of animal management practices by modulating animal sensory systems. Chemical signals, mostly known as pheromones, have a great potential in this regard. This study was conducted to determine the influence of short-term male rabbit exposure to different biological secretions, potentially pheromone-mediated, on reproductive parameters of males. Four groups of 18 males each were exposed to A) doe urine, B) 2-phenoxyethanol, C) doe vaginal swab, and D) distilled water (control), three times over a 2.5h exposure window, just before semen collection. Semen volume, sperm concentration and motility, as well as subpopulation analysis of the spermatozoa were assessed for each condition. Additionally, testosterone levels in blood samples were monitored at five time points over the 2.5 h exposure window. We found a higher percentage of motile, progressive, fast progressive and mid-progressive spermatozoa in any of the three experimental groups compared to the control group. In contrast, the semen volume and the percentage of immotile and non-progressive spermatozoa was generally higher in the control group. We then identified a higher proportion of a subpopulation of fast and progressive spermatozoa in groups A, B, and C compared to group D. Our data indicates that sperm motility increases when animals are exposed to specific biological fluids potentially containing pheromones, and that an increase in sperm volume does not correlate with an increase in spermatozoa concentration, progressiveness, and speed. Finally, no differences in testosterone levels were found among comparisons, although males of groups A and C (exposed to natural female biological fluids) showed a tendency towards higher testosterone levels. In conclusion, our results indicate that rabbit sperm quality increases upon exposure to the biological secretions proposed, thereby supporting further investigation into their molecular identity. This exploration could eventually pave the way for implementing the use of pheromones in rabbit husbandry to enhance reproductive and productive parameters in farmed rabbits.

423 Comparative post-weaning performance characteristics of four breeds of rabbit in hot humid climate of Nigeria

Abstract Rabbits are one of the most popular livestock breeds raised for their meat, fur, and companionship. Rabbit meat is fast gaining prominence as a healthier meat compared with beef, mutton, pork and chevon, which are mostly consumed in Nigeria. This study investigated breed differences in mortality, survival rates and post-weaning growth rate of rabbits reared under inimical environmental conditions. The animals were fed commercially compounded feed with 18% crude protein and 2300Kcal metabolizable energy with intermittent feeding of Panicum sp and Tridax sp. The study area, located at latitude 6.5867° N and longitude 3.9700° E, had an average daily temperature of 35°C and relative humidity of 64%, which negatively impacted the adaptation, survival rates and growth performance of the rabbits. A total of 48 weaner rabbits 8 wk of age, comprising 12 each (9 does and 3 bucks) of Checkered, Chestnut, Dutch and Hyla breeds were reared for 10 wk post-weaning. Mortality was recorded across the breeds and the body weights (BW) of the rabbits were also recorded on a weekly basis for the entire 10-wk period. The study evaluated survival rates across breeds and sex and BW gain. Statistical analyses were conducted using the Minitab software for Chi Squared test of independence for counts and descriptive statistics and general linear model analysis of variance for bodyweight gain. The statistical model describing the analysis was Yijk = µ + αi + (α:β)ij + eijk where αi is the ith fixed effect of breed and βj is the jth fixed effect of sex. The model accounted for 67.03% variation in total weight gain. Further mean separation was done using the Tukey’s multiple comparison procedure. Mortality rates across breeds on the average was 56.25%, with Checkered, Chestnut, Dutch and Hyla respectively recording 66.67%, 41.67%, 50.00% and 66.67% mortality, respectively. Mortality rate across sexes was 63.89% for does and 33.33% for bucks; however, mortality rates were independent (P > 0.05) of both breed and sex with a Chi-Squared value of 2.285 and 3.41, respectively, despite the numerical differences in mortality rates across breeds and sexes. Average total BW gain during the study period across the breeds and within breeds is as presented in Table 1. The nesting of sex within breed revealed that the only significant (P > 0.05) difference was noticed between the Hyla buck and Chestnut doe, while other means were not statistically different (P > 0.05). The Chestnut breed with the least BW gain adapted well in the environment with greatest survival rate, while the Hyla breed had the greatest BW gain and least survival rate throughout the study. This study indicated a negative relationship between survival rates and BW gain, that lighter breeds of rabbit tend to have greater survival rates than the heavier breeds.

Morphometric Characterization and Production System of Rabbits Reared in the Amoron'i Mania Region Madagascar

A positive and significant correlations (p < 0.001; r=0.71) between age and LW was founded, and a significant correlations (rho= 0.79 vs rho= 0.89) with body length (BL). In summary, our study provides valuable insights into the demographics of rabbit farming, breed characteristics and morphological measurements.

Correlation Analysis among the Various Inbreeding Coefficients of Pannon Ka Rabbits

In a closed population with a limited population size, mating of related animals is unavoidable. In this study, the genealogy data of a synthetic maternal rabbit breed called Pannon Ka were used to calculate different inbreeding coefficients. The evaluated animals were born between 1995 and 2020, and the pedigree consisted of 5819 animals that originated from 4205 rabbit does and from 1314 rabbit bucks. The pedigree was further extended with 16,013 dummy progeny records in order to calculate litter inbreeding coefficients. Besides the conventional Wright inbreeding coefficients, the so-called ancestral and new inbreeding coefficients were also calculated using the gene dropping method. By the end of the evaluated period, the litter inbreeding increased to almost 11 and 60% for Wright and Ballou inbreeding, while the Kalinowski and the Kalinowski new inbreeding coefficients were 9.25 and 16.67%, respectively. Correlation coefficients were calculated for the does and for the litters. Finally, the effects of pedigree length and completeness were also taken into account using the complete generation equivalents in a partial correlation analysis. Based on the results, it could be seen that the different ancestral inbreeding coefficients had high correlation. Similarly, the conventional Wright inbreeding coefficients showed strong correlation with the new inbreeding coefficients. On the contrary, the correlation between ancestral and new inbreeding coefficients was low. Taking the complete generation equivalent into account did not give unambiguous results. It could be concluded that the different inbreeding coefficients are based on different concepts, and they are clearly different population parameters.

Genetic assessment of litter size, body weight, carcass traits and gene expression profiles in exotic and indigenous rabbit breeds: a study on New Zealand White, Californian, and Gabali rabbits in Egypt

Rabbits are essential for commercial meat production due to their efficient growth and productivity, breeds like New Zealand White (NZW), Californian (CAL), and Gabali (GAB) rabbits offer unique genetic traits in litter, growth, and carcass traits. This study aimed to evaluate heritability (h2), genetic and phenotypic correlations (rg and rp) for litter size, body weight and carcass traits across California (CAL), New Zealand white (NZW) and Gabali (GA) rabbits. Along with exploring gene expression profiles of TBC1D1, NPY, AGRP, POMC, Leptin, GH, GHR, IGF-1, CAA, GPR, ACC, CPT1, FAS, and CART in the brain, liver, and meat tissues of different rabbit breeds. The breed genotype had a significant impact on litter size (LS), litter weight (LW), body weight at 12 weeks (BW12), and daily weight gain (DWG) traits. NZW rabbits displayed superior performance in terms of litter size and litter weight, while CAL rabbits recorded the highest values for BW12 and DWG. Heritability estimates (h2) were generally low for litter size (ranging from 0.05 to 0.12) and medium for body weight (ranging from 0.16 to 0.31). Both genetic (rg) and phenotypic (rp) correlations for litter size were positive and moderate (ranging from 0.08 to 0.48), while correlations for body weight ranged from 0.21 to 0.58. Additionally, CAL rabbits exhibited higher carcass traits compared to NZW and GA rabbits. In terms of breed-specific gene expression patterns, New Zealand White (NZW) rabbits displayed the highest expression levels of key genes related to energy metabolism (TBC1D1), appetite regulation (NPY, AGRP, POMC), nutrient transport (CAA), and G protein-coupled receptors (GPR) in both brain and liver tissues. Californian (CAL) rabbits exhibited superior gene expression of the ACC gene in brain tissue and GH, GHR, and IGF-1 genes in brain and meat tissues. Gabali (GAB) rabbits demonstrated the highest expression levels of TBC1D1, NPY, AGRP, GPR, and ACC genes in meat tissues. These breed-specific gene expression differences, combined with genetic evaluation efforts, have the potential to enhance reproductive and productive performance in rabbits, offering valuable insights for rabbit breeding programs and genetic selection.

Association of single nucleotide polymorphisms in Neuropeptide Y (NPY) and Phosphoglycerate Mutase 2 (PGAM2) genes with growth traits in rabbits

Genetic improvement of local rabbit breeds using modern approaches such as marker-assisted selection requires accurate and precise information about marker‒trait associations in animals with different genetic backgrounds. Therefore, this study was designed to estimate the association between two mutations located in the Neuropeptide Y (NPY, g.1778G > C) and Phosphoglycerate Mutase 2 (PGAM2, c.195 C > T) genes in New Zealand White (NZW), Baladi (BR), and V-line rabbits. The first mutation was genotyped using high-resolution melting, and the second mutation was genotyped using the PCR-RFLP method. The results revealed significant associations between the NPY mutation and body weight at 10 (V-line) and 12 weeks of age (NZW, BR, and V-line), body weight gain (BWG) from 10 to 12 weeks of age (BR), BWG from 6 to 12 weeks of age (NZW, BR, and V-line), average daily gain (NZW, BR, and V-line, and BR), growth rate (GR) from 8 to10 weeks (V-line), 10 to 12 weeks (BR), and GR from 6 to 12 weeks of age (BR, and V-line). The PGAM2 mutation was associated with body weight at 10 (V-line) and 12 (NZW, and V-line) weeks of age, with significant positive additive effects at 12 weeks of age in all breeds, and was associated with BWG from 8 to 10 and 10 to 12 in BR, and BWG from 6 to 12 weeks of age (NZW, and BR), and average daily gain (NZW, and BR), and was associated with GR form 8 to 10 weeks (BR), from10 to 12 weeks (BR, and V-line) and from 6 to 12 weeks (BR). The results highlighted the importance of the two mutations in growth development, and the possibility of considering them as candidate genes for late growth in rabbits.

Dyspnea with multiple bilateral lung opacities on CT scan

A 58-year-old man was admitted with a typical presentation of acute left heart failure. However, the patient showed a partial response to the anti-heart failure therapy. Following admission, a continuous fever was monitored, and a CT scan revealed that multiple opacities on bilateral lungs had progressed. Bronchoscopy was performed, and Coxiella burnetii was detected by Metagenomic next-generation sequencing (mNGS) in bronchoalveolar lavage (BALF), and transbronchial lung biopsy showed organizing pneumonia. Considering that the patient had a history of rabbit breeding and delivery, with some newborn rabbits dying before he became ill, organizing pneumonia secondary to Q fever pneumonia was diagnosed. Anti-Q fever treatment was initiated and the patient's temperature returned to normal. Glucocorticoid was administered after adequate treatment for Q fever. The patient's symptom of dyspnea relieved soon and opacities on CT scan were absorbed remarkably. The final diagnosis was organizing pneumonia secondary to Q fever pneumonia accompanied with left heart failure.

Molecular detection and association of 12.1kb deletion within the high mobility AT-hook 2 gene in the Netherlands dwarf rabbit (Oryctolagus Cuniculus).

Rabbits are mainly bred for human consumption and medical research. However, it has been recently showed that several rabbit breeds are also kept as pets for human leisure. The Netherlands dwarf rabbit is currently in the immense interest of many Vietnamese customers due to its personality and miniature stature. However, 12.1kb deletion from position 44,709,089 to 44,721,236bp in the high mobility AT-hook 2 (HMGA2) gene on chromosome 4 was identified as the structural variant causing dwarfism and altered craniofacial development in this breed. It has been documented that HMGA2 plays an important role in regulating growth and individuals with genotype HMGA2 del/del are fatal several days after birth. Despite the economically high value of the Netherlands dwarf rabbit, there has been no study on the genetic survey of lethal alleles in this breed in Vietnam. The aim of this study is to develop a fast and reliable method to screen the frequency of lethal alleles of HMGA2 in the South of Vietnam. Rabbit saliva was collected, and DNA extraction was followed. Multiplex polymerase chain reaction (PCR) with three primers was optimized and performed to detect the presence of 12.1kb deletion within the HMGA2 sequence. Our data showed that the 12.1kb deletion in the Netherlands dwarf rabbit population was detected by our optimized multiplex PCR. In 100 rabbit animals, 34 and 16 individuals were homozygous wild type (+/+) and homozygous mutant (del/del), respectively, while 50 rabbits were heterozygous. The frequency of HMGA2 lethal allele carrier was 66% (66/100 individuals). Our results indicated that we successfully developed a fast, accurate multiplex PCR to detect carrier individuals. Verification of the genotypes was followed by sequencing. We recommend implementing our multiplex PCR procedure in genetic selection for carrier and homozygous wild-type animals in the mating scheme to prevent the lethality of the rabbit offspring. Additionally, awareness should be raised among rabbit breeders to monitor the genetic makeup of the Netherlands dwarf rabbit populations. However, due to the limitation of the sample size, more samples should be taken in future studies to obtain the genetic frequency of the HMGA2 lethal allele more accurately.

RAPID: A rabbit pregnancy diagnosis device based on matrix optical sensing

Effective early pregnancy diagnosis is crucial for commercial rabbit breeding. Early pregnancy diagnosis enables the implementation of staged feeding for pregnant does, effectively preventing excessive weight gain and reducing the high mortality rates of kits during the birthing stage. This not only enhances production efficiency but also ensures the health and well-being of the breeding rabbits. The study introduces a method and device, the Rabbit Pregnancy Identification Device (RAPID), for detecting rabbit pregnancies using matrix optical sensing. RAPID comprises eight sensor modules and a central host unit. Each sensor module is equipped with three LEDs emitting light at wavelengths of 660 nm, 850 nm, and 940 nm, along with two photodiodes for data collection. A mobile application was developed to enable flexible control of the device. Signal-to-noise ratio tests were conducted to evaluate the stability of data collection by the device across varying light intensities. The experimental results reveal a direct correlation between light intensity levels and the signal-to-noise ratio of collected data. Notably, under a light intensity level of 4, RAPID achieves a signal-to-noise ratio ranging from 42 to 45 dB, satisfying the necessary criteria for data collection. Different classification models were trained using sample data from 216 does across various batches, and their generalization capabilities were evaluated. The experimental findings indicate that the optimal time for RAPID to diagnose the pregnancy status of does is on the 14th day after insemination, achieving an accuracy of 86.63 % and a recall of 80.49 %. Moreover, the model exhibits a degree of generalization, achieving an accuracy of 78.36 % when classifying another batch of sample data. RAPID achieves an accuracy of 97.25 % for pregnancy diagnosis of older does, which is 7.44 % higher than that of younger does; the accuracy rate for pregnancy diagnosis of does with sparse hair is 86.92 %, which is 4.78 % higher than that of does with dense hair. By comparing the effectiveness of using data from 8 sensor modules and data from a single sensor module for pregnancy diagnosis of different batches of does, it was found that the former exhibits more stable generalization capability in doe pregnancy detection.

Neoplastic and non-neoplastic lesions in biopsy samples from pet rabbits in Hong Kong: a retrospective analysis, 2019-2022.

Rabbits are popular pets in the urban environment of Hong Kong, ranking third behind cats and dogs. Here we describe the frequency of neoplastic and non-neoplastic lesions in biopsies from pet rabbits submitted to the CityU Veterinary Diagnostic Laboratory between 2019 and 2022, comprising 247 tissue samples from 243 rabbits collected by veterinarians in 19 veterinary clinics. Among the 243 rabbits, there were 128 females (65 spayed), 114 males (54 castrated); sex information was not provided for 1 rabbit. The rabbit breeds included 45 Lionhead, 35 Dwarf, 14 Lop, 11 Dwarf Lop, 5 French Lop, 3 Angora, 2 Dutch, 2 Holland Lop, and 1 each of Netherland Dwarf, Velveteen, Mini Lop, and New Zealand White. The mean ages of rabbits with neoplastic and non-neoplastic lesions were 7.1 and 5.7 y, respectively. The most common neoplastic lesions were adenocarcinoma (26.4%), trichoblastoma (21.4%), sarcoma (9.4%), and thymoma (8.2%). The most common non-neoplastic lesion was uterine cystic endometrial hyperplasia (14.8%), followed by dermal abscess formation in the ventral abdomen or skin of the head (12.5%). Although a broad spectrum of other lesions was described, our findings in biopsies from pet rabbits in Hong Kong are consistent with those in other jurisdictions.

Conformation-associated health in pet rabbits in the UK: A VetCompass cohort study.

Domestic rabbit breeds vary substantially from the wild rabbit body type. However, little is known about how the conformation of pet rabbits influences their health. Data were extracted from VetCompass anonymised clinical records of rabbits under UK primary veterinary care during 2019. The study included 162,107 rabbits. Based on 88,693 rabbits with relevant breed information recorded, skull shape was classified as brachycephalic (79.69%), mesaticephalic (16.80%) and dolichocephalic (3.51%). Based on 83,821 rabbits with relevant breed information recorded, ear carriage was classified as lop-eared (57.05%) and erect-eared (42.95%). From a random sample of 3933 rabbits, the most prevalent disorders recorded overall were overgrown nail(s) (28.19%), overgrown molar(s) (14.90%) and obesity (8.82%). Compared to those with a mesaticephalic skull shape, brachycephalic rabbits had lower odds of obesity, anorexia and gastrointestinal stasis and higher odds of perineal faecal impaction, tear duct abnormality and haircoat disorder. Compared to erect-eared rabbits, lop-eared rabbits had higher odds of perineal faecal impaction and tear duct abnormality. A large proportion of records with incomplete breed information hindered full analysis for breed-related and conformation-related attributes. Limited evidence for major links between skull shape or ear carriage conformations andoverall disorder risk suggests that factors such as husbandry or even just living life as a domesticated species may be bigger drivers of common health issues in pet rabbits in the UK.

Evaluation of genetic diversity within different rabbit (Oryctolagus cuniculus) genotypes utilizing start codon targeted (SCoT) and inter-simple sequence repeat (ISSR) molecular markers

Abstract. This work aimed at studying the genetic diversity among different rabbit genotypes reared in Egypt by two different molecular markers (start codon targeted, SCoT, and inter-simple sequence repeat, ISSR) to improve breeding strategies. Five different groups of rabbits were used Gabali (Gab), New Zealand white (NZW), Californian (Cal), Rex, and Papillon (Pap). DNA was extracted and analyzed using SCoT and ISSR-PCR, and the obtained fragments were analyzed. Six SCoT primers scored 60 bands with 78.33 % polymorphism; primer SCoT 6 was the most polymorphic marker with 92.31 % polymorphism, while SCoT 5 was the lowest with 60 %. A dendrogram based on SCoT-PCR revealed that the Rex breed was the most genetically different. Seven ISSR primers gained 56 bands in total with 49.762 % polymorphism. ISSR 4 was the most polymorphic primer that detected 75 % of polymorphism, while ISSR 6 was not able to detect any polymorphism. It was suggested that the SCoT markers may be more effective than ISSR for differentiating and identifying the genetic variations within investigated breeds. Also, the usage of molecular markers of SCoT and ISSR may be more proper for calculating genetic diversity and common ancestry among tested rabbit breeds. Furthermore, evaluating genetic variability is important for enhancing existing breeds' adaptation to ecological alterations and crucial for preservation or breeding purposes.