Search

Background: Chinese indigenous rabbits have distinct characteristics, such as roughage resistance, stress resistance and environmental adaptability, which are of great significance to the sustainable development of the rabbit industry in China. Therefore, it is necessary to study the genetic diversity and population structure of this species and develop genomic resources., Results: In this study, we used restriction site-associated DNA sequencing (RAD-seq) to obtain 1,006,496 SNP markers from six Chinese indigenous rabbit breeds and two imported rabbit breeds. Jiuyishan and Fujian Yellow rabbits showed the highest nucleotide diversity (π) and decay of linkage disequilibrium (LD), as well as higher observed heterozygosity (Ho) and expected heterozygosity (He), indicating higher genetic diversity than other rabbits. The inbreeding coefficient (F IS ) of New Zealand rabbits and Belgian rabbits was higher than that of other rabbits. The neighbour-joining (NJ) tree, principal component analysis (PCA), and population structure analysis of autosomes and Y chromosomes showed that Belgian, New Zealand, Wanzai, Sichuan White, and Minxinan Black rabbits clustered separately, and Fujian Yellow, Yunnan Colourful, and Jiuyishan rabbits clustered together. Wanzai rabbits were clearly separated from other populations (K = 3), which was consistent with the population differentiation index (F ST ) analysis. The selection signature analysis was performed in two populations with contrasting coat colours. With Sichuan White and New Zealand rabbits as the reference populations and Minxinan Black and Wanzai rabbits as the target populations, 408, 454, 418, and 518 genes with a selection signature, respectively, were obtained. Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed on the genes with a selection signature. The results showed that the genes with a selection signature were enriched in the melanogenesis pathway in all four sets of selection signature analyses., Conclusions: Our study provides the first insights into the genetics and genomics of Chinese indigenous rabbit breeds and serves as a valuable resource for the further effective utilization of the species., (© 2021. The Author(s).)

The objective of this study was to assess the possibility of using two nonlinear models, i.e. the von Bertalanffy and Gompertz functions, for fitting growth curves of Popielno White and New Zealand White rabbits. The study was conducted using 37 Popielno White (21 male and 16 female) and 55 New Zealand White (28 male and 27 female) rabbits. The nonlinear regression procedure (NLIN) in SAS 9.4 software was used to model the rabbits’ growth curves from birth to 12 weeks of age. To see how rabbit growth might progress in subsequent weeks, we extrapolated the weights of the rabbits up to the age of 30 weeks. Six criteria were used to compare models: mean error, mean squared error, mean absolute error, quotient between the error sum of squares and observed sum of squares, corrected Akaike information criterion, and Bayesian information criterion. The shape of all curves was sigmoid, and both models fitted well to the data from birth to 12 weeks of age, i.e. during the interpolation process. A problem with the fit occurred later, during the extrapolation process, i.e. when the models were used to predict the animals’ course of growth in subsequent weeks. When body weight was extrapolated in later weeks of life, the fitting of the von Bertalanffy model was slightly worse, and asymptotic body weight was overestimated. To predict the further course of rabbit growth in practice, the Gompertz function would be a better choice. The Gompertz model could also be a helpful tool for breeders to describe the growth process of rabbits and to select a more economically profitable breed. [ABSTRACT FROM AUTHOR]

diets on growth performance. 30 rabbits from New Zeeland breed, on 55 days of age (±2) were randomly allocated to three experimental groups for 47 days (until reach 2100g of body weight). The experimental design consisted of three dietary treatments: 1) control group received standard compound feed - unsupplemented; 2) the first experimental group (M3) received diet supplemented with 3% thyme leaves powder instead of alfalfa hay; 3) the second experimental group (M5) received diet supplemented with 5% thyme leaves powder instead of alfalfa hay. Individual rabbits' body weights were recorded weekly. Feed intake and feed conversion rate were determined weekly per group. Carcass characteristics were determinate at the end of the trail. The results of this study have shown that thyme inclusion at level up to 3 or 5% did not adversely affect rabbit's performance. [ABSTRACT FROM AUTHOR]

The present study was performed to assess the genetic variations among six rabbit breeds in Egypt based on mitochondrial 16S rRNA sequences. The length of partial mitochondrial 16S rRNA in the six rabbit breeds ranged from 546 bp to 558 bp. The sequenced regions were submitted to GenBank/NCBI under accession numbers (MW052052 - MW052057). The average content of A+T was 57% in all breeds. Among breeds, the percentages of genetic distance values were ranged from 0.000 to 0.004. The highest P-distance (0.004) was found between the New Zealand White breed and all other breeds. The results support the suitability of mitochondrial 16S rRNA for genetic diversity analysis of rabbit breeds and the applicability for future research on genetic relationships and the phylogeny of rabbit breeds. [ABSTRACT FROM AUTHOR]

Background: The study evaluated the growth performance, haemabiochemical and antioxidant profile of two breeds of rabbits fed diets containing varying levels of Rhizopus stolonifer fermented cocoa pod husk meal (FCPHM). Cocoa pod husk meal was taken through solid-state fermentation for a period of 2 weeks using Rhizopus stolonifer as its starter culture. One hundred and eighty, 5-week-old unsexed weaned rabbits 90 New Zealand white (NZW) and 90 Chinchilla (CHL) were randomly allocated into three dietary treatments, Diets I, II and III (0%, 12.5 and 25%FCPHM, respectively), and were arranged in a 2 × 3 factorial design (2 breeds and 3 diets) of a randomized block design. Results: The study showed that the breed effect and dietary treatment were significant (p < 0.01) for total weight gain and feed conversion ratio with NZW breed fed 12.5% FCPHM having higher values than CHL breed. Serum total protein concentration was significantly (p < 0.05) influenced by the dietary treatment, while alanine aminotransferase, globulin and total protein concentrations were significantly (p < 0.01) affected by the breed effect. The interactive effect of breed and dietary treatment was only significant (p < 0.05) for serum albumin concentration. Malondialdehyde concentration was significantly influenced by both dietary treatments (p < 0.05) and breed (p < 0.001) factors. Conclusion: It was observed that CHL rabbits were more predisposed to stress than the NZW rabbits as indicated by the lipid peroxidation values, and according to this present finding, 12.5% FCPHM is recommended as active feed ingredient in rabbit diets. [ABSTRACT FROM AUTHOR]

The effect of breed and season on rabbits' fur characteristics under Egyptian semi-arid conditions was studied in this research. Fifty-nine male rabbits aged 3-3.5 mo of Gabaly (GB, n=21) and New Zealand White (NZW, n=27) breeds and their crossbred (NZW×GB, n=11) were studied during two subsequent seasons; summer (n=31) and winter (n=28). Skin samples were taken pre-slaughtering to determine the histological parameters, skin layer thicknesses and physical traits of fur fibres. After slaughter, rabbits' furs were chrome tanned to determine physical and chemical properties. Results showed that all histological parameters of follicle dimensions were affected (P<0.01) by season, breed and their interaction. In summer, primary follicles had larger follicle dimensions and produced coarser fibres than in winter, whereas opposite results were observed for the secondary follicles. Additionally, the uniformity of fibre diameter distribution and hair length of furs were higher (P<0.01) in summer than in winter. Results indicated the role of the seasonal variations in body coat to accommodate the climatic changes. NZW rabbits were superior (P<0.01) in most histological parameters of follicle dimensions, followed by NZW×GB crossbred and finally GB rabbits, while NZW×GB crossbred produced finer (P<0.01) fur fibre than NZW and GB rabbits. Otherwise, influence of season and breed were negligible on the skin layer thickness values and the physical and chemical fur properties. Consequently, the study concluded that tanned rabbit furs are suitable for manufacturing leather garments when used alone, while reinforcing the fur with textile padding may increase their utility for other leather manufacturing purposes. [ABSTRACT FROM AUTHOR]

Background: Scabies, caused by infestation of the mite Sarcoptes scabiei, is one of the most severe ectoparasitic diseases in rabbits. Scabies seriously affects the commercial rabbit breeding, causing severe economic losses. Host resistance to S. scabiei is an important factor in further development of the rabbit industry. In the present study, we compared the host resistance to S. scabiei var. cuniculi of a new breed of domestic rabbit propagated by the Sichuan Animal Sciences Academy (QiXing rabbit, QX) compared with that of a traditional rabbit breed in the domestic rabbit industry (IRA rabbit, IRA). Methods: Both QX and IRA rabbits were experimentally infested with live S. scabiei var. cuniculi mites for 48 h. Then, during the course of four-week experimental infestation period, the body weight of rabbits was recorded every two weeks for calculating body-weight variations in comparison to the non-infested control rabbits. Skin lesions in the foot area were assessed on weekly basis and serum samples were tested weekly for the estimation of changes in the total antibody levels (IgG, IgE and IgM). Moreover, DNA extracted from the blood samples was amplified for analysis of the genetic diversity in the major histocompatibility complex, class II, DQ Alpha (MHC-DQA) gene. Results: Compared to the IRA rabbits, the QX rabbits showed a significantly higher (P < 0.05) relative body weight gain compared to the non-infested control rabbits and significantly lower (P < 0.05) scores for foot skin lesions and higher levels of IgG, IgE and IgM at weeks 1 to 4, week 2 and week 1 post-infestation, respectively. Furthermore, a polymorphism site at position 103 bp of exon two of MHC-DQA gene and a different gene frequency were found between two rabbit breeds, suggesting the genetic basis for the differential host resistance to the S. scabiei var. cuniculi between two rabbit breeds. Conclusions: The QX rabbits showed higher host resistance to S. scabiei var. cuniculi compared to the IRA rabbits at the clinical, immunological and genetic levels. These results provide a reference for the breeding of rabbits with adequately improved and sustained host resistance to scabies in the domestic rabbit industry. [ABSTRACT FROM AUTHOR]

The article presents data obtained during the study of the influence of various environmental factors on the biochemical parameters of blood serum in different rabbit breeds differing in directional productivity. It has been established that irrespective of the pedigree of rabbits, when growing under conditions of comparatively intensive contaminated (CIC) conditions in blood serum, the amount of total protein and albumins decreases. And the amounts of globulins and transferrin were high. [ABSTRACT FROM AUTHOR]

Genetic resource banks (GRB) are a valuable tool for maintaining genetic variability and preserving breeds from pathogens or catastrophe, enabling us to assess and correct breeding schemes, minimizing the impact of genetic drift and facilitating diffusion. This study tests their efficiency in re-establishing two extinct populations of a synthetic rabbit line selected for daily weight gain, using vitrified embryos from two generations (18th and 36th) separated by 15 years of genetic selection. The effect of long-term storage of vitrified embryos in liquid nitrogen was also evaluated. A total of 516 vitrified embryos using the same protocol were transferred into 54 recipients. The embryos had been maintained in liquid nitrogen during 2 different periods, (i) 1 year (301 embryos and 26 transfers, 36th generation) and (ii) 15 years (259 embryos and 28 transfers, 18th generation). A total of 80.0% (8/10 to 18th) and 60.0% (9/15 to 36th) of the foundational sire families were eventually re-established. Over approximately one year, animals within each population were crossed to produce the next generation and re-establish the original population size. Our study demonstrated that our GRB of embryos vitrified 15 years ago is a successful strategy to re-establish rabbit populations to continue the breeding programme. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Animal & Poultry Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study was conducted to investigate the effect of organic acids, medium chain fatty acids and yeast cell walls on the productivity, physiological state and intestinal histomorphology of the rabbits. The study was conducted with 14 Californian breed rabbits. The rabbits (77-161 days old) were assigned to two treatment groups (7 rabbits per each treatment group). The dietary treatments were 1) control diet, 2) diet supplemented with the additive Luscent (dosage 1 kg/t of feed) - from INNOV AD nv/sa, Belgium - a commercially available product that medium chain fatty acids, Yeast cell wall (Saccharomyces cerevisiae), butyric acids esters, plant extracts. The rabbits were kept in individual wire-net cages with grid floors and an individual vessel for watering and feeding. Storage conditions were the same for both groups. Rabbits were fed twice a day (ad libitum). During the feeding trial the following parameters were analysed: rabbits' performance, blood parameters, development of intestinal tract, pH and dry matter content in different parts of the intestine, the villus height and the crypt depth. The inclusion of organic acids, medium chain fatty acids and yeast cell walls in the compound feeds increased the rabbit's body weight, weight gain, growth rate and decreased feed intake. The feed additive Luscent had a positive effect on the length of the intestinal tract, the villus height in the duodenum. [ABSTRACT FROM AUTHOR]

In the last 1.5 decade in Romania has launched a few very important breeding programmes in the field of rabbit breeding. Namely three rabbit breeds were created in a period of ten years (this period represents the time from the start of the first project until the three breeds were officially recognized by the Ministry of Agriculture and Rural Development through the National Livestock Production Agency "Prof. Dr. K. G. Constantinescu"). Before 2016 Romania had no certified rabbit breed. The three rabbit breeds we are talking about are: Rabbit of Cluj, Giant of Transylvania and the Szekler Rabbit. The latter (Szekler Rabbit) has its breed standard published in 2016, were three color variety is mentioned (the black sallander, the havana-sallander, and the blue-sallander color variety). The creation of the black sallander Szekler Rabbit was previously described in 2015. So far there is no publication concerning the creation/development of the havana-sallander and the blue-sallander color variety. Therefore the present paper aims to describe in detail, step by step the havana color variety breeding programme. Briefly havana-sallander Szekler Rabbit descends from the black sallander Szekler Rabbits, which was infused with havana color gene (bb). The infusion crossings involved the French Lop and Giant Papillon (the solid color variety) and California (havana-himalaya) breeds certainly all of them havana colored. During the breeding programme, beside the new/external blood infusion through the three breeds mentioned (havana gene carriers) also consaguinization was used in order to stabilize the color pattern. From here it can be deduced that the havana-sallander Szekler Rabbit has a polyphyletic origin. Although the havanasallander Szekler Rabbit is a very recent creation, it is already present in the rabbit shows, attaining very promising results even in a national show in Romania in 2017. [ABSTRACT FROM AUTHOR]

With >1600 documented human infections with Middle East respiratory syndrome coronavirus (MERS-CoV) and a case fatality rate of approximately 36%, medical countermeasures are needed to prevent and limit the disease. We examined the in vivo efficacy of the human monoclonal antibody m336, which has high neutralizing activity against MERS-CoV in vitro. m336 was administered to rabbits intravenously or intranasally before infection with MERS-CoV. Prophylaxis with m336 resulted in a reduction of pulmonary viral RNA titers by 40-9000-fold, compared with an irrelevant control antibody with little to no inflammation or viral antigen detected. This protection in rabbits supports further clinical development of m336. [ABSTRACT FROM AUTHOR]

Our study aimed at investigation of the main performance indices of young rabbits at slaughtering, depending on the breed, at 90 days of age. Three different and well-known rabbit breeds were used in this study: White Giant, New Zealand Red, and Giant Papillon. In terms of body weight at slaughtering and carcass weight, the best results were obtained in the case of Giant White rabbit, while the poorest were in the case of New Zealand Red. In terms of slaughter yield with head, the best results were recorded for Giant Papillon rabbit, while the poorest were obtained in the case of New Zealand Red. However, the situation was rather different for the slaughter yield without head. For this index, the Giant White rabbit showed better results than both other two rabbit breeds, Giant Papillon and New Zealand Red. Although a medium sized breed carcass should be of higher quality that those obtained from large breeds, in our case the New Zealand Red showed the poorest meat/bones proportion at 90 days when compared to Giant White rabbit and Giant Papillon rabbit. The last breed mentioned, Giant Papillon, showed the best results for carcass quality and meat/bones proportion. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

6 293 records of three diallelic crossings among four rabbit breeds (California, C; Chinchilla, CH; New Zealand, N and Semigiant, S) were used to determine the individual heterosis (hI), maternal (gM) and direct (gI) additive effects on the prolific features at birth: total born (TB), born alive (BA) and viability at birth (VIAB). A mixed generalized linear model was used with the help of macro GLIMMIX from SAS for estimating the average of each genetic group. The model considered, as fixed effects, the genetic group and the experiment as well as the random effect of the parturition order. The estimations were made through the linear contrast among the average obtained for each genetic group, according to the model of Dickerson. Differences among the genetic groups showed the advantages of the pure N for each features. The maternal additive effects were more important for these features than the direct. The litters of N breed benefit in the TB, while for the VIAB the young rabbit benefit with C genes. The maternal effects were favorable for the CH and N breeds, as maternal breeds for these indicators. A significant heterosis was found for the TB and BA between - 4.6 y - 6.5% for F1 CN and CHN crossing. The differences between the evaluated crossbreeding for these features can be attributed to the maternal and direct additive effect, favorable for using the N and C breeds as paternal and the CH and N as maternal breeds. [ABSTRACT FROM AUTHOR]

The carcass characteristics of the Albanian local rabbit breed farmed in two different production systems were compared. The carcasses were measured and retailed according to the norms of the World Rabbit Scientific Association. The rabbits that were reared on the family farms, the traditional system (n=36), showed a lower live weight at the slaughter age of 101 days (2025 vs. 2303 g, P<0.03), as well as a lower dressing out percentage (59.41 vs. 60.53%, P<0.05), than the rabbits (n=40) reared on the commercial farms, the conventional production system. A higher proportion of the hind part of the carcass (42.11 vs. 36.93%, P<0.05) and two shoulders (17.5 vs. 16.1%) were observed in the conventional production system when compared to the traditional one. The average of the pelts was also different at 286.5 g (traditional system) and 328.2 g (conventional system) (P<0.01), while the ratio of the pelts to the live weight at slaughter age were equal. The production system did not affect the total inedible parts percentage. In conclusion, the local rabbits reared in the conventional systems showed better carcass characteristics. [ABSTRACT FROM AUTHOR]

Se realizaron 4725 observaciones de tres cruces dialélicos completos entre cuatro razas de conejos (California, C; Chinchilla, CH; Nueva Zelanda, N y Semigigante, S) para determinar los efectos raciales y la heterosis en rasgos de prolificidad. En el primer estudio, se aplicó un modelo lineal generalizado mediante el procedimiento GENMOD del SAS (2007), que consideró los efectos de raza (paterna, materna y su interacción), paridad y generación. En el segundo, se utilizó un modelo mixto mediante el PROC MIXED, también del SAS, que consideró al genotipo (cruce vs. puros) como aleatorio y la paridad y la generación, como fijos. Los BLUP resultantes del segundo modelo se utilizaron en el cálculo de heterosis. Se analizaron los indicadores nacidos totales (NT), vivos (NV) y número de destetados (ND). La raza materna fue el único efecto importante para los NT y NV. Se destacó la Chinchilla, con más de siete gazapos para ambas medidas. Se halló heterosis positiva no significativa en los cruces recíprocos CCH-CHC para cada uno de los rasgos en estudio, así como en los CN-NC para el ND. En las combinaciones restantes la heterosis fue negativa o nula. El empleo de la C como raza materna es una vía para mejorar los rasgos de NT y NV. Con el cruce CCH-CHC, se obtienen ventajas al nivel de la heterosis para todos los rasgos de prolificidad estudiados, y con CS-SC para el ND. Estos resultados demuestran que el cruzamiento es una alternativa para incrementar la productividad en diferentes explotaciones cunículas. [ABSTRACT FROM AUTHOR]

An experiment was conducted to evaluate the effect of replacing fish meal with grasshopper meal on haematology, blood chemistry and carcass characteristics of growing rabbits. Forty rabbits of mixed breeds, aged 6-10 weeks, were randomly assigned to the dietary treatments in a complete randomized design with eight rabbits per treatment. The rabbits were fed with diets containing 0, 1.25, 2.50, 3.75 and 5% grasshopper meal in diets designated as T1 (control), T2, T3, T4 and T5, respectively. The experimental diets and clean drinking water were supplied ad libitum throughout the experimental period of nine weeks. At the end of the feeding trial, three rabbits per treatment were slaughtered for carcass evaluation, while blood samples were collected for analysis. The result of the experiment showed significant differences (P<0.05) among the treatments for packed cell volume (PCV), red blood cell count (RBC), white blood cell count (WBC), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) but there was no significant effect (P>0.05) on haemoglobin and mean corpuscular haemoglobin concentration (MCHC). The results also revealed significant differences (P<0.05) for serum globulin, glucose, cholesterol, urea and creatinine but there was no significant effect (P>0.05) on serum albumin and total protein. The results of carcass characteristics showed significant differences among treatments (P<0.05) for slaughter weight, carcass weight, dressing percentage, skin pelt, tail, feet and abdominal fat. The slaughter weight and carcass weight were better in groups receiving 2.5% grass hopper meal (50% fish meal replacement). From the results, it can be concluded that inclusion of 2.50% grasshopper meal as a replacement for fish meal (50% replacement) has no adverse effects on the haematological parameters, serum biochemistry and carcass characteristics of rabbits. [ABSTRACT FROM AUTHOR]

The article focuses on the study conducted to examine the role of P-Loop residues in K+ channels. The difference in the P-loop sequence of HCN channels reveals that the residues could account for differences in channel families. It also mentions threonine is highly conserved in K+ channels. It establishes the presence of the TIGYG pore-lining sequence that does not confer K+ selectivity to rabbit HCN4 channels. Further it suggests that differences in selectivity of HCN4 versus K+ channels genrate from differences outside the P-loop region.

In hybrid zones between genetically differentiated populations, variation in locus-specific rates of introgression may reflect adaptation to different environments or adaptation to different genetic backgrounds. The European rabbit, Oryctolagus cuniculus, is well-suited to studies of such hybrid zone dynamics because it is composed of two genetically divergent subspecies that hybridize in a zone of secondary contact in central Iberia. A species-wide survey of allozyme variation revealed a broad range of locus-specific divergence levels (FST ranged from 0 to 0.54, mean FST=0.16). Interestingly, the two loci that fell at opposite ends of the distribution of FST values, haemoglobin α-chain (HBA) and haemoglobin β-chain (HBB), encode interacting subunits of the haemoglobin protein. The contrasting patterns of spatial variation at these two loci could not be reconciled under a neutral model of population structure. The HBA gene exhibited higher-than-expected levels of population differentiation, consistent with a history of spatially varying selection. The HBB gene exhibited lower-than-expected levels of population differentiation, consistent with some form of spatially uniform selection. Patterns of linkage disequilibrium and allele frequency variation do not appear to fit any simple model of two-locus epistatic selection.Heredity (2008) 100, 602–609; doi:10.1038/hdy.2008.26; published online 30 April 2008 [ABSTRACT FROM AUTHOR]

The objectives of this study were to describe and compare means and measures of variability of fiber characteristics and fiber production between genetically furred and furless rabbits and among classes of furless rabbits. An F1 generation of rabbits was produced by mating New Zealand White does to a rare, furless Mini Lop buck. All F1 offspring had normal coats of fur. Inter se random matings of the F1 stock (barring full-sibling matings) were made to produce the F2 generation that consisted of approximately 75% furred and 25% furless progeny. Furless animals were further subjectively classified into 3 distinct classes (1 to 3) having increasingly more fur. In yr 1, 17 furred and 20 furless rabbits (age 28 to 49 d) were randomly assigned to growing pens, and in yr 2, 17 additional furless and 9 additional furred rabbits were included to increase the size. After 6 wk, the rabbits were weighed, and a measured area of fur (∼20 cm²) was shorn from the left flank of each rabbit. This fiber was weighed and measured for staple length, fiber diameter, prickle factor (% of fibers >30 μm in diameter), and fiber curvature. Fiber production per unit area of skin was calculated and fiber production per animal was estimated. In yr 2, all of the furless and 2 of the furred rabbits were shorn over their entire bodies to obtain direct measurements of total fur weight. Furless rabbits were 9% heavier (1,941 vs. 1,783 g of BW, P < 0.01) and produced approximately 90% less fiber per unit area of skin than furred rabbits (1.74 vs. 15.83 mg/cm², P < 0.01). The fibers from furless rabbits were shorter (1.54 vs. 2.56 cm, P < 0.01) and coarser (15.8 vs. 14.5 μm diameter, P < 0.01) than those from furred rabbits and exhibited greater prickle factor (11.3 vs. 3.5%, P < 0.01) and curvature values (47.5 vs. 38.5 deg/mm, P < 0.01). Class 3 furless rabbits were heavier than rabbits of classes 1 and 2 (2,075 vs. 1,817 and 1,981 g of BW, respectively, P < 0.05). Means for actual total fiber production per animal for classes 1 to 3 were 0.64, 2.07, and 8.68 g, respectively, compared with 23.0 g for furred rabbits (P <0.01). Although some similarities were present, several of the correlations involving fiber properties and BW were substantially different (e.g., BW vs. staple length and fiber diameter vs. weight of fiber per unit area) for furred and furless groups. These results, and those reported elsewhere from a series of experiments, support the potential for production of furless rabbits in arid and tropical environments. [ABSTRACT FROM AUTHOR]

Although the European rabbit ( Oryctolagus cuniculus) is used both in agronomics and in research, genomic resources for this species are still limited and no microsatellite-based genetic map has been reported. Our aim was to construct a rabbit genetic map with cytogenetically mapped microsatellites so as to build an integrated genetic and cytogenetic map. A reference population of 187 rabbits comprising eight three-generation families with 10–25 offspring per family was produced. One hundred and ninety-four of 305 previously identified microsatellites were included in this study. Of these, 158 were polymorphic with two to seven alleles. The map reported here comprises 111 markers, including 104 INRA microsatellites, five microsatellites from another source and two phenotypic markers ( angora and albino). Ninety markers were integrated into 20 linkage groups. The remaining 21 microsatellites mapped to separate linkage groups, 19 with a precise cytogenetic position and two with only a chromosomal assignment. The genetic map spans 2766.6 cM and covers 20 rabbit chromosomes, excluding chromosomes 20, 21 and X. The density of this map is limited, but we used it to verify the location of angora and albino on chromosomes 15q and 1q, respectively, in agreement with previously published data. This first generation genetic/cytogenetic map will help gene identification and quantitative trait loci mapping projects in rabbit. [ABSTRACT FROM AUTHOR]

One hundred and two pet rabbits were examined and their husbandry, health and welfare were reviewed. The most common breed was the dwarf lop (n=38). The most common problem was dental disease, which affected 30 rabbits although only six of their owners were aware of the problem, which was significantly associated with feeding a rabbit mix. All the rabbits were housed in ‘hutches’ at some stage, but 89 had access to the outside and 47 came inside the home at times. Hutches bought at pet shops were significantly smaller than home-made hutches. Forty-five of the rabbits were housed alone; the relationships between rabbits with rabbit companions were described by their owners as ‘very friendly’ for 84 per cent of them and ‘quite friendly’ for the rest. [ABSTRACT FROM AUTHOR]

A complete diallel cross involving 3 maternal lines of rabbit was performed to estimate cross-breeding parameters for functional longevity. This trait was defined as the ability to delay involuntary culling. The lines considered, A, V, and Prat, had all been selected by litter size at weaning for a long period. Data were related to a total of 653 does belonging to the 9 genetic types from the diallel cross; does were reared and bred on the same commercial farm. Survival analysis `was performed using a Cox proportional hazard model. The model incorporated time-dependent factors, such as year-season, litter size, and the interaction between cycle and physiological status of the female; time-independent factors, such as the genetic type of the doe; and sire and dam random factors. Crossbreeding parameters were estimated from the solutions obtained for the type of doe and its estimated variance-covariance matrix, using a generalized least squares procedure. The estimated parameters were the differences between lines in direct genetic effects and maternal genetic effects and individual heterosis. Relevant differences were observed in direct genetic effects between lines A and Prat but not in any maternal effects. Heterosis was found to be significant and favorable between lines A and Prat, and between the lines V and Prat. The magnitude of this effect was variable but important, especially in the first cross. Results stress the importance of using crosses between specialized lines to produce does for intensive meat rabbit production. [ABSTRACT FROM AUTHOR]

The article examines carcass traits in three rabbit breeds. Forty-two rabbits from the New Zealand White, California and Chinchilla breeds were slaughtered and studied by researchers. The study found that the rabbits from the Chinchilla breed had the best weights of the different carcass components.

The article presents a study which examined the reproductive and pre-weaning performance of purebred imported rabbits in Cuban conditions. The materials and methods used are described, as well as the statistics of fertility and prolificacy. Results showed that the differences of the imported breeds, compared to that of the national breeds, indicated which of the imported breeds can make a more interesting contribution to the national breeds.

The article presents a study which compared four breeds of rabbit in a genetic unit with restricted feeding of concentrate and forage in tropical conditions. The materials and methods used are described, as well as the number of observations per breed and year. It is concluded that the breeds have very variable reproductive performances according to the environmental conditions.

This article presents a study that examined productive indicators and the influence of environmental effects on each breed of rabbits and on the population. Cuban Semi-Giant, Chinchilla, New Zealand and California are the breeds analyzed in this study. The preweaning stages considered in each breed are cited. Results of the study showed that month and year were highly significant for all traits and breeds. It also found that the only traits influenced by all the effects were fertility, the percentage of weaned litters (WL) and litter weight (LW).

The article discusses research which compared the growth and feed efficiency of four rabbit breeds. Forty eight analyses of variance of fixed effects were carried out to study liveweight, gain, viability, consumption, and conversion of the feed and dry matter of the diet. The study suggests that the use of molasses in separate troughs for measuring consumption and its effect on the use of the total diet proved to be efficient in rabbit breeding.

Presents a study which evaluated Altex and New Zealand White breeds of rabbit for postweaning individual growth and litter traits. Materials and methods; Direct breed additive effects on individual and litter traits; Results and discussion.

Studies the distribution and density of rabbit warrens on the Southern Tablelands of New South Wales. Relation of the distribution to agricultural practices and the rabbits' biological requirements; Prevalence of the highest densities of warrens in the agriculturally less valuable areas; Association of the number of burrows in use with the number of rabbits living in the warren.