The present study characterized movement restriction in reproducing does kept in a part-time collective system in parks with different group size (2 or 4 does, i.e., 2 or 4 modules joined to have 100-cm and 200-cm long parks), grouping time (12, 15 or 18 d after kindling) and observation day (at grouping time and after 3 d). For this purpose, the number of different types of hops was considered, i.e. number of single hops and series of consecutive double, triple and multiple hops. On average, single hops accounted for 53.64% of all hops observed; double hops were 28.39% and triple hops averaged 12.56%, whereas multiple hops (>3) accounted for 5.41%. When group size increased from 2 to 4 does, the occurrence of multiple hops increased (3.84 to 6.99% of total hops; P<0.001). The number of hops (whatever type) significantly decreased when grouping time increased (from 10.18 to 8.12 and 6.92 per time interval per doe with grouping at 12, 15 and 18 d post-partum, respectively; P<0.001) and when comparing the grouping day with 3 d after grouping (9.72 vs. 7.09 hops; P<0.001). In conclusion, movement restriction, defined as the inability to perform three consecutive hops, does not occur when the enclosure has a minimum length of 100 cm. Nevertheless, the increase of the park length is associated with an increase in the number of hops (all types), including multiple hops.

In this study we determined clinical and epidemiological aspects of clinical pregnancy toxaemia/ketosis (CPTK) in female rabbits housed in commercial farms in Portugal and Spain. Information was gathered through 12 611 visits to 1422 doe farms during 1994-2024. The median size of the doe farms visited by the end of the period was 868 does (mean size: 1067 does, ranging from 100 to 6000 does). Diagnoses were based on macroscopic post-mortem examinations by veterinarians. Over the 31-yr study, we conducted 5117 necropsies of does on 607 rabbitries. Within a sub-set of 126 farms, we identified 401 does presenting CPTK lesions. The at-risk female population across the 126 farms totalled 152 218 does. From this data, we estimated the relative incidence of the disease at 0.26% of at-risk females on the day of the visit. The median size of farms with females at risk was 400 does (minimum to maximum: 100-3015 does). In this study, age emerged as a significant risk factor: does in their first-pregnancy or first-lactation were more predisposed to CPTK, mostly between days 27 and 32 of gestation. Additionally, 20.2% of females that died from CPTK experienced abortions between days 23 and 30 of pregnancy. Seasonal variation also appeared to influence disease occurrence, with lower incidence during autumn. CPTK in farmed female rabbits carries a poor prognosis, often going unnoticed due to the large number of kindlings in each batch. From this study we infer that the most efficient control strategies on farms were medical prophylaxis and management-based prevention. These include monitoring indoor climate and providing careful feeding for young does. Clinically, it is useful to check for the presence of hard faeces bound with hair.

The aim of this study was to evaluate the effects of dietary supplementation with organic zinc (zinc methionine with 12% of Zn) at levels exceeding standard nutritional recommendations on sexual behaviour (reaction time to ejaculation), semen quality and quantity, and sperm production in rabbit bucks. Five months old New Zealand White rabbits (n=33) were randomly assigned to three treatments: T1) basal diet (BD) or control, without the addition of zinc, considering only the provision of the ingredients included in the diet (25 mg Zn kg–1); T2) 150 Zn: BD+150 mg of organic Zn; T3) 200 Zn: BD+200 mg of organic Zn. A completely randomised design was employed, with 11 replicates per treatment. Each buck constituted an experimental unit. Six semen collection sessions were carried out with two ejaculations per buck, one collection per week. The dietary Zn concentration in the diet was shown to affect curvilinear sperm velocity (VCL; P=0.026), curvilinear sperm distance (DCL; P=0.007) and the percentage of normal sperm (PNS; P=0.02). The VCL, DCL and PNS in rabbits with 200 Zn were higher than those in the 150 Zn and the control group. First ejaculates showed greater (P<0.05) reproduction potential due to: 27% less reaction time, 87.4% more presence of gel and increased seminal volume (42.7%), sperm concentration per ejaculate (41.7%), straightness of track (2.8%) and number of seminal doses (8.3), whereas the amplitude of lateral head displacement and curvilinear distance were higher (P<0.05) than in the second ejaculate. The BD bucks and those with 150 mg Zn kg–1 in their diet improved sperm kinematics, seminal quality and reproductive potential. The diet with 200 mg Zn kg–1 (T3) may have adverse effects on the reproductive performance of male rabbits, which may impact the doe’s prolificacy and fertility levels.

This work studied the effects of nano-chromium (nano-Cr) and trivalent chromium (Cr III) on hormones, semen quality and growth traits in NZW rabbits at sexual puberty age. Thirty-six male rabbits (6-wk-old; 1200±4 g IBW) were penned into 3 groups (12/each): control, Cr (III) as CrCl3 (0.5 mg/animal/wk) and nano-Cr (0.5 mg/animal/wk). The doses were administered individually as oral sips and the study lasted 100 d, until the rabbits reached 20 wk of age. Both Cr (III) and nano-Cr treatments increased T3 and T4 levels with values of 1.22, 1.16, 2.85 and 2.72 ng/mL; P<0.01, respectively, compared to the control. Testosterone and IGF-1 concentrations were highest in the nano-Cr group, reaching 1.22 ng/mL and 0.84 ng/mL, respectively. The Cr (III) group showed the highest final body weight (3502 g), total gain (2367 g) and average daily gain (23.67 g/d), along with the best carcass weight (2710 g) and dressing percentage (77.38%). Reproductive performance was most improved by nano-Cr, which increased sperm concentration (71.87×10⁶/mL), ejaculate volume (0.86 mL), progressive motility (64.17%) and the percentage of live sperm (91.30%), while reducing libido by 6.85 s and nearly doubling the total viable sperm per ejaculate from 28.93×10⁶ to 56.41×10⁶. In conclusion, nano-Cr at 0.5 mg/animal/wk seems to be a more appropiate supplement for boosting reproductive traits in male rabbits at sexual puberty age, while Cr (III) (0.5 mg/ animal/wk) seems to be more useful for meat production purposes.

The growth hormone (GH) gene and its associated regulatory components play critical roles in regulating growth in rabbits and it has been suggested as a potential marker for marker assisted selection. However, the reported association between polymorphisms in GH gene and growth traits in rabbits remains inconsistent. Therefore, this study evaluated the association between polymorphisms in the GH gene and growth performance traits in rabbits using meta-analysis. A systematic review was conducted, following the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines, and studies reporting the association of GH polymorphisms with body weight (BW) and average daily gain (ADG) were screened against predetermined inclusion criteria. A total of 7 studies met the inclusion criteria, from which 21 data points were extracted for the meta-analysis. SPSS software was used to calculate standardised mean differences, perform heterogeneity tests and publication bias assessment, while OpenMeta® Analyst software was used to conduct meta-regression and sensitivity analyses. Six genetic models including the codominant (three models), recessive, dominant and over-dominant were evaluated. GH gene polymorphisms significantly influenced BW under the co-dominant (CC vs. CT) and over-dominant (CT vs.CC+TT) models, with CT genotype exhibiting higher BW. However, no significant association was observed between GH gene polymorphisms and ADG under any genetic model. In addition, heterogeneity was significant across studies, with I² values exceeding 50% for all genetic models, suggesting that systematic differences rather than random sampling error contributed to the observed variations. Meta-regression identified location, genotyping method and breed as significant moderators influencing the association between GH gene polymorphisms and BW. These results suggest that GH gene variants, particularly the CT genotype, may serve as potential markers for improving growth traits in rabbits through selective breeding.

Transcriptome sequencing was performed to analyse the differentially expressed genes (DEGs) of skeletal muscle in Fujian white rabbits at different stages, to help establish gene expression datasets for further investigation of the mechanisms underlying genetic skeletal muscle growth in Fujian white rabbit. The transcriptomes of skeletal muscle in Fujian white rabbits at five growth stages with 25 rabbits (5 rabbits per stage) were analysed. Double fluorescence staining was performed on skeletal muscle sections at three postnatal stages for muscle fibre classification and statistical analysis. A total of 9737 DEGs were acquired from five stages. The Kyoto Encyclopaedia of Genes and Genomes analysis showed that 8249 genes were enriched in 1148 pathways, of which 67 were significantly (P<0.05) enriched, mainly in the mitogen-activated protein kinase signalling pathway, glucagon signalling pathway and peroxisome proliferator-activated receptors signalling pathway associated with normal skeletal muscle development. Among all groups, skipped exons were the most abundant alternative splice event. Many of the DEGs were well known to be related to growth of skeletal muscle in Fujian white rabbits including myogenic factor 5, Myomesin-2, Phosphoglycerate mutase 2, Myostatin and Myogenic factor 6, which were verified by quantitative reverse transcription polymerase chain reaction. These results contribute to define the molecular regulatory mechanism of muscle growth and development in Fujian white rabbits and serve as a theoretical basis for improving the meat production and growth of meat rabbit breeds.

The purpose of this research was to compare the growth performance and gene expression variations in three genetic groups of meat rabbits: Alexandria line (AA), V line (VV) and the cross between Alexandria line males and V line females (AV). For the three genetic groups, which were raised under Egyptian environmental conditions, the studied offspring growth traits were individual weight at weaning (WW, 4 wk) and the end of fattening period (MW, 9 wk) and individual daily weight gain. A total number of 22 bucks, 93 does and 792 kits were used in the study. The Gompertz model was periodically used to examine the rabbits’ growth. Five kits per group were used to collect liver tissue samples at marketing age (63 d) for gene expression analysis. According to the findings, the AV strain had a body weight of 135 g more than the AA strain and 277 g higher than the VV strain. The AV strain also showed a decreased daily feed consumption and a better feed conversion ratio. With strong coefficients of determination (R²=0.86), the Gompertz growth curve successfully approximated the growth curves for all genotypes. Our results also revealed that VV strain had the highest myostatin expression, while AA and cross strains had the lowest. In contrast, there was a statistically significant difference in the growth hormone receptor (GHR) and the growth hormone secretagogue receptor mRNA levels between the VV, AA and AV strains, with the cross strain having the highest levels of GHR mRNA expression. These findings suggest that the AV strain reached maturity earlier than the AA and VV strains, which is beneficial for optimising growth and breeding processes. Furthermore, rabbits’ development, metabolism and general health may be affected by hereditary factors that impact gene expression in liver tissues. To better understand the processes at work and their possible uses in breeding programmes, further study is required.

Rabbit farming is emerging as an alternative livestock enterprise in the Philippines, particularly in response to the pork supply deficit caused by African Swine Fever. Despite its technical viability and low production cost, rabbit farming systems in the Philippines remain largely informal and face multiple socioeconomic and market-related constraints. Using a Rapid Rural Appraisal approach, this study engaged 290 rabbit farmers across five provinces to identify key barriers and potential development pathways. Findings revealed that most respondents were smallholder farmers with limited experience, integrating rabbit raising as a supplementary livelihood. The sector is male-dominated, with men older, more experienced and earning significantly higher household income than female raisers. While both sexes tended to raise similar rabbit breeds, males have more rabbits kept and derive income primarily from farming, whereas females are more engaged in non-farming income sources. Major constraints included limited market access, high breeder stock costs, inadequate veterinary and technical services and the absence of structured training programmes. Market-side issues such as low consumer acceptance and the limited availability of rabbit meat in public markets further hindered viability. Despite these challenges, farmers identified practical solutions, including the need for technical training, cooperative marketing, access to starter kits (cages, breeding stock, feeds), and local feed development. These insights underscore the critical need for an integrated support mechanism. Value chain enhancement, market integration and consumer education are essential to promote the growth and sustainability of the rabbit farming sector in the region.

The 49th Symposium of the Spanish Association of Cuniculture (ASESCU) was held last May in Burgos (Castilla y León; Spain). The event was organised in collaboration with Union de Pequeños Agricultores y Ganaderos (UPA). During the congress, two main lectures were presented. First, Luis Ángel Quintela, from Universidade de Santiago de Compostela, explained how animals use pheromones to communicate and explored their potential to reduce stress and improve animal breeding in farming. Then, Francisco Xavier Mora, from Universitat Autònoma de Barcelona, talked about re-emerging diseases found in recent years in rabbit farming. The challenges to face with the possible incoming legislation on rabbit housing were discussed by producers, researchers, rabbit meat distributors, housing manufacturers and livestock associations in a round table. Moreover, four simultaneous and interactive round tables were held during a coffee break, with dynamic discussions on processed rabbit meat products, the new legislation about rabbit health, good farming practices and the use of additives in rabbit nutrition. More than a hundred people joined the congress, including technicians, farmers and researchers. In the following pages you can see the contributions on genetics and reproduction, nutrition, housing and welfare, environmental control and pathology.

One of the main challenges in commercial rabbit production is the high nutritional demands in primiparous females, which, together with their limited intake capacity, reduces their body fat stores and could be partly responsible for their low reproductive performance. Supplementation strategies with rich sources of polyunsaturated fatty acids in primiparous rabbits could compensate for their low reproductive performance. Therefore, the aim of the present study was to evaluate the addition of increasing levels of conjugated linoleic acid (CLA) to the diet of rabbits on embryo development and embryo quality in New Zealand rabbits. Thirty New Zealand females aged 28-30 d and weighing an average of 587.5±35 g at the start of the experiment were randomly distributed into three feeding treatments: T0: (n=10) commercial diet, TCLA1 (n=10): commercial feed +2.5% CLA, TCLA2 (n=10): commercial feed +5.0% CLA, and were fed ad libitum with commercial balanced feed containing 18% crude protein and 12% crude fibre during the experimental phase (120 d). The females were exposed to a male for mating and sacrificed at 72 h postcoitus to obtain the embryos. No significant differences (P>0.05) were observed in the final weight of the animals between treatments. However, females fed with CLA presented a higher body condition compared to the control group (P<0.05). The TCLA2 group females presented an average of 9.5±1.467 embryos recovered per female, showing a significant difference (P<0.05) compared to the TCLA1 and T0 treatments. The embryos from the TCLA1 and TCLA2 treatments presented a higher percentage of excellent and good quality embryos compared to the control group (P<0.05). In conclusion, supplementation with 2.5 and 5.0% conjugated linoleic acid does not affect the final weight of female rabbits but significantly improves their body condition, the number of embryos recovered and embryo quality. These results highlight the potential of CLA as a nutritional tool to optimise reproductive efficiency in rabbit production systems.