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In the last decades, the European wild rabbit, particularly the Oryctolagus cuniculus algirus, a keystone species in the Iberian Peninsula ecosystems, declined severely, raising concerns from the wildlife authorities. The hunting calendar in Portugal limits sampling collection to a narrow window of few months annually. Nevertheless, governmental wildlife protection laws allow live rabbit sampling for population and sanitary evaluations. The aim of this study is to adjust blood collection protocols from the external jugular vein (EJV) described for domestic rabbits to the wild rabbit. Collection of peripheral blood is problematic in the wild rabbit given its small body size and the reduced calibre of vessels but mostly its nervous disposition and fragility. We describe in detail a procedure for EJV blood collection in 30 wild rabbits after sedation with midazolam. Emphasis is given to protocol adjustments for wild rabbit. Heart rate, respiratory rate and body temperature were assessed before sedation, after sedation but before collection and after blood collection. Sedation onset took on mean (SD) 8 ± 2 min. The technique allowed the collection at least 1 ml of blood, a satisfactory volume for routine laboratory testing. The differences observed in heart and respiratory rates before and after blood collection were not statistically sig-nificant, indicating that no cardiorespiratory interference occurred due to venepuncture. Recovery from sedation took on mean (SD) 17 ± 2 min. All animals were set free during the first hour after blood collection. This work aims to demonstrate that blood collection under sedation is a safe and feasible procedure in wild rabbits when practiced by experienced veteri-narians. At no time, whatsoever, was the physiological homeostasis at risk and no injuries were inflicted on the animals. To our knowledge this report constitutes the first guided description of blood collection from the EJV in sedated O. c. algirusand the first collection of physiological parameters measured under different conditions.

Objectives To calculate the size and dioptric power of a posterior chamber intraocular lens (IOL) to achieve emmetropia in adult rabbits and to compare the dioptric power calculation results using a proprietary predictive formula to a retinoscopy-based method. Animals studied Three wild rabbit cadavers, seven pet rabbits with cataracts and ten healthy pet rabbits. Materials and Methods Implant size was calculated using a capsular tension ring (CTR) (Acrivet®, Berlin, Germany). Published and cadaveric biometric data were used in the predictive formula. An IOL power-escalation study compared the predicted values to the refraction results of one pet rabbit (P1) fitted with a + 41D canine IOL (Acrivet®) and six pet rabbits (P2-P7) fitted with prototype IOLs (Acrivet®). Retinoscopy of 10 healthy pet rabbits served as controls. Results A 13.5 mm CTR fitted in all rabbits and permitted the use of a 13 mm IOL. The predicted IOL power ranged between +24D and +25D. The +41D IOL resulted in a refraction error of +8D. Progressive recalculation through a calibration formula led to the insertion of three +49D IOLs in two pet rabbits and a refraction of +6D to +8D, followed by seven +58D IOLs in four pet rabbits and a refraction median of 0D (range: −1.5D to +1D). Conclusions A 13 mm prototype IOL of +58D achieves emmetropia and is of adequate size for rabbits. The combined use of a CTR and retinoscopy is a useful method to calculate the size and refractive power of a new, species-specific, veterinary IOL.

Wild predators are targeted if they are perceived to affect game species or domestic animals. Over the last century, the direct persecution of birds of prey and mammalian carnivores has led to their widespread decline, even local extirpations. Many such cases involved the illegal use of poisoned bait. We used 1,305 detected poisoning events and 59 biophysical variables to construct a distribution model of illegal poisoning throughout Andalusia, southern Spain. We chose this region because the largest number of poisoning events recorded in Spain were detected in Andalusia during the period 1990–2005. Our results showed greater incidence of poisoning was correlated with areas of high predator richness and high wild rabbit hunting yields. Thus, we hypothesize that wildlife managers should be able to estimate current and potential poisoning areas using frequency of poisoning events data. Managers can then focus control within those areas identified as conflict zones and establish surveillance schemes that prevent the loss of wildlife within the targeted areas. Our results have potential application in strategic planning for conservation of vulnerable high-profile species such as birds of prey and mammalian carnivores in southern Spain and other regions. © 2012 The Wildlife Society.

In some circumstances, the presence of adipocere may retard decomposition and complicate postmortem interval estimation. This article explores the correlation between Accumulated Degree Days (ADD) and early stage formation of adipocere. Sixty wild rabbit (Oryctolagus cuniculus) carcasses were used in this experiment; a control group (N = 30) deposited directly on the ground surface and an experimental group (N = 30) completely submersed in water in individual buckets. Data (water and inner body temperature, pH, and total body score) were collected every 100 ADD. Results indicated that early stage adipocere is correlated to ADD and that its formation on submersed remains is more likely to occur after 630 ADD. Skin sloughing promoted the formation of adipocere. No adipocere was formed on any of the control group rabbits. This study also highlights the fact that multiple factors influence adipocere formation and it is suggested that further research needs to be conducted into this area.

The social organisation of a free-living population of wild rabbits was examined. Discrete breeding groups were recognised which consisted of individuals who shared access to underground refuges. Males attempted to maximise their access to females by a) occupying large home ranges; b) defending female access indirectly through territorial defence; c) defending female access directly within groups. Females defended nest site access within groups. Intergroup interactions between females were rare because of limited home range overlap. Interruption of female-female aggression by males was observed suggesting that conflicts of interest arose between the sexes. Adult-juvenile aggression was primarily intra-sexual; females initiated more interactions than males who adopted a protective role in some cases.

Summary Wild rabbit populations from several parts of south-eastern Australia and from Tasmania and Macquarie Island were tested for the As1, As2, As3 (a locus) and the As4, As5, As6, As9 (b locus) allotypic IgG markers. All markers except As6 were present in the Australian mainland and Tasmanian populations, and there appeared to be a significant increase in As1 frequency with decreasing rainfall. On the other hand the Macquarie Island samples were virtually all homozygous As1 at the a locus and lacked As6 and As9 at the b locus. These results are discussed against the background of the known history of the introduction of the rabbit into the areas studied. It was felt that ‘founder effect’ could account for the observed distribution on Macquarie Island. However, the As1 cline in Australia warrants further study, particularly in relation to possible selective effects.

Evidence for two new alleles (TfC and TfD) at the transferrin locus (Tf) in wild rabbit, Oryctolagus cuniculus, is presented. Blood samples were collected in Continental Portugal (178 individuals), and in the Azores Islands of Terceira (52) and S. Miguel (59). The frequency of TfA, which is the only allele detected up to now in domestic rabbits, varied from 0.20 +/- 0.13 to 0.95 +/- 0.05 in the populations sampled in Continental Portugal. In the island populations sampled the frequency of TfA was greater than 0.8.

The European wild rabbit (Oryctolagus cuniculus) is the main prey for several endangered species and an important game species in the Iberian Peninsula. However, over the last several decades 2 diseases, myxomatosis and rabbit hemorrhagic disease (RHD), have contributed to a decline in rabbit populations. In Spain, vaccination campaigns against both diseases and the translocation of vaccinated rabbits are frequently used in projects aimed at stimulating the recovery of wild populations. We estimated which factors related to body condition were associated with successful immunization by vaccination. In 191 adult wild rabbits, we calculated a body-mass index and analyzed a number of biochemical parameters and antibody concentrations before and after vaccination. Results showed that, respectively, 81 and 84% of initially seronegative rabbits seroconverted after vaccination against myxomatosis and RHD. We also found that RHD antibody concentrations after vaccination were positively associated with total protein concentrations at the moment of vaccination in all rabbits, whereas RHD antibody concentrations were negatively related to the creatinine concentration at the end of our study for initially seronegative rabbits. Our results suggested that In wild rabbits vaccination was an effective way of increasing antibody concentrations and, thus, of fighting myxomatosis and RHD, although the intensity of the immune response was conditioned by the body condition of individual rabbits. Consequently, rabbit translocations could be improved by avoiding the translocation of individuals with poor body condition and by improving vaccination protocols. In addition, success rates in mass vaccination programs carried out in free-living wild populations may be increased if the body condition of individuals is evaluated before vaccination campaigns are carried out.

We examined an index of abundance for rabbits Oryctolagus cuniculus involving a spotlight plot count (SPC) using capture-mark-resighting as a reference method in five study areas. In these areas, density varied over a wide range, from 0.7 to 23.4 rabbits/ha, which is representative of most European populations. The SPC precision was good, as the coefficient of variation ranged within 5-54%, the median value being 17%. We showed area and year effects on the index and a significant relationship between the SPC and ln(density) (P < 0.0001). The logarithmic relationship between density and SPC suggests a saturation of the index when density increases. Despite the fact that the SPC index was highly correlated with density, its ability to detect population changes was rather poor. This lack of sensitivity may be due to factors affecting rabbit detectability such as climatic conditions, lunar phases, observers, changes in crop rotation and, more generally, to factors affecting the number of rabbits abov...

European wild rabbits originated in southwestern Europe but have been introduced into many other countries world-wide, becoming serious pests in many instances. As a consequence of rabbits being regarded so differently, applied research for their management often has opposing goals, namely their conservation or their control. Furthermore, modern gene technology has led to the concept of using genetically modified myxoma viruses for rabbit management, again with quite contrary aims in mind. In this paper we explain the possible ecological and economic consequences of using these genetically modified viruses inappropriately and we consider whether national and international regulations are sufficient to prevent improper use. If international regulations are inadequate, molecular biologists and ecologists must consider the consequences of their research and advice beyond their own country to avoid unwanted impacts.

In last week’s issue Vic Simpson and others ( VR , September 30, 2017, vol 181, pp 350-351) describe a shot wild rabbit in good condition that was found to have an unusual form of myxomatosis consisting of multiple dermal masses over the lumbar region. It is not known to what extent that case may be related to ‘lumpy bunny syndrome’ occasionally seen in …

THE emergence of rabbit haemorrhagic disease (RHDV) virus 2 (RHDV2) in Europe (Le Gall-Recule and others 2011) has been associated with declines in wild rabbit ( Oryctolagus cuniculus ) populations (Delibes-Mateos and others 2014, Guerrero-Casado and others 2016, Monterroso and others 2016) previously exposed to RHDV. All RHDV genotypes of the G1–G6 genogroups, hereafter referred to as RHDV, belong to the same antigenic serotype (Le Gall-Recule and others 2013). The unique antigenic nature of RHDV2 (Le Gall-Recule and others 2013, Barcena and others 2015) is reflected in its capacity to kill rabbits vaccinated against RHDV (Le Gall-Recule and others 2011, Dalton and others 2014, McGowan and Choudhury 2016) and its rapid spread in Europe (Dalton and others 2012, Le Gall-Recule and others 2013, Abrantes and others 2014, Baily and others 2014, Westcott and others 2014) and Australia (Hall and others 2015) with associated peaks in RHD epizootics. The capacity of RHDV2 to overcome RHDV immunity, reported so far only in vaccinated rabbits, may partly explain the observed decline in wild rabbit populations where RHDV had already been circulating. Here the authors report the infection by RHDV2 of three Australian wild rabbits with a known RHDV antibody-positive serological history, with clinical signs of RHD visible in one fresh carcase, the first documented cases of RHDV-immune wild rabbits being infected with and/or succumbing to RHDV2 infection. This demonstrated capacity of RHDV2 to overcome immunity derived from natural infections with RHDV supports an immunogenic difference between RHDV and RHDV2 at the level of serotype. With the emergence and spread of RHDV2 …

Since myxomatosis, around half a million rabbits are restocked annually in France and the Iberian Peninsula. The effectiveness of this approach to restoration is still unknown. In this study, the efficacy of traditional restocking was evaluated by marking rabbits with radiocollars and reproducing the methodology usually employed in Spain. The estimated mean survival rate for the first 10 days after release was very low (

Rabbit numbers are rising in most parts of Britain. Previous research in southern England has indicated that the rate of increase in spring due to breeding may vary according to soil type. This has serious implications for the likely rate of invasion into new habitats and for planning control operations. To investigate the hypothesis, post-mortem examinations of over 2500 rabbits from 14 sites on sand, chalk or clay were made. The length of the breeding season and percentage of females breeding differed significantly between soil types but litter size and intra-uterine mortality did not. The product of breeding season length and litter size results in an estimate of annual productivity per adult female. This was 22, 20, and 14 young born per female on clay, chalk, and sandy sites, respectively. Rabbits may invade new habitats, such as set-aside, at different rates according to soil type and therefore require different levels of control regime for population management.

Four batches of wild rabbit (Oryctolagus cuniculus: winter, spring, summer and autumn) were caught at the end of the respective season of the year. A study of the meat chemical composition of these animals was carried out. The classes and amounts of total, apolar and polar lipid fractions, and their fatty acids, have been extensively studied. The total, apolar and polar lipid contents from the muscle of the four batches ranged from 37 to 14, 30-1 to 8–4 and 9–0 to 4–8 g kg−1 FW respectively. Triglycerides accounted for more than 59% of the apolar lipids, and phosphatidylcholine and phosphatidyl-ethanolamine were the major phospholipids (>44% and >35% of total phospholipids, respectively). Almost always, 16:0, 18:0, 18:1 and 18:2 were the more abundant fatty acids of the total lipid fraction. Many seasonal differences may be observed in the fatty acid composition of total and apolar lipid fractions which are obviously related to the kinds of feed available in each season. One of the most significant differences is in 18:1 concentration. This fatty acid accounted for more than 50% in the apolar lipids from rabbits caught in autumn whereas the same fatty acid never reached 30% in other seasons. On the contrary, 18:2 and 20:0 showed a lower concentration in the autumn batch by comparison with those of the other seasons.

The effects of different rabbit grazing regimes on the concentration and relative amounts of individual glucosinolates were studied overwinter in the green tissue of two oilseed rape cultivars (Bienvenu, a single-low type, and Ariana, a double-low type) and two forage rape cultivars (Hobson and Bonar). Grazing significantly increased total glucosinolate content. Within this general increase, the proportion of aliphiatic glucosinolates was reduced whereas the proportion of both indole and phenylethyl glucosinolates increased. Possible reasons for such changes are discussed.

WE wish to report the detection of a new variant of rabbit haemorrhagic disease virus (RHDV) (Lagovirus, Caliciviridae) which is circulating in France and has been causing high mortality in domestic and wild rabbit populations since the end of the summer of 2010. Rabbit haemorrhagic disease (RHD)

Evidence for the genetic determination of A100 allotypic specificity suggests that it is the product of an allele at the alpha locus. The A100 allotypic specificity was detected in a wild rabbit lacking all the known specificities of the a series. None of the 8 rabbits possessing the A100 allotypic specificity possessed two allotypic specificities of the a series. The concentration of A100+ molecules is larger in the serum of a presumably homozygous rabbit than in that of a presumably heterozygous rabbit. In the sera of heterozygous A100+ rabbits, the A100 allotypic specificity and the known specificity of the a series are carried by different molecules. The determinants responsible for the A100 allotypic specificity are present both on IgG and IgM. They are located on the heavy chain and the Fab fragment of IgG. A family of variants of A100 specificity has been detected and cross-reactivity between A100, a1 and a3 specificities has been found. This was detected and studied with anti-a3 antisera. It seems that A100 allotypic specificity is closer to a3 specificity than a1 is to a3 specificity.

The uterine histology of wild rabbits caught in the non-reproductive season in the Revinge area in southern Sweden was studied (as part of a larger study on the biology of the wild rabbit). The uteri of the yearlings—which do not reproduce—had a low weight and a juvenile histology with a relatively thick, cell-sparse lamina propria and a weak muscular layer. After the breeding season the uteri of the adults gradually entered a regressed winter state, characterized by a well-developed muscular layer, a thin, cell-dense lamina propria and a low mucosal epithelium with few glands. A few yearlings that had ovulated shared this picture. The regressive state gradually disappeared in spring.

Information on the infestation of wild rabbits by Leporacarus gibbus (Pagenstecher), Cheyletiella parasitivorax (Megnin) and Haemodipsus ventricosus (Denny) for Victoria is presented and discussed. Infestation rates were lowest in the dry north-west region of the state. In other regions most rabbits were infested but there was a wide range in infestation numbers in all regions.

The quality of the food eaten by rabbits can be predicted from the quality of the recently ingested food in the anterior portion of the stomach using the equation: crude protein in food (% dry weight) = 1.42 × crude protein in stomach (% dry weight). The relationship which food bears to the ecology of rabbits differs from population to population. In semi-arid north-western and mediterranean New South Wales changes in food quality are closely related to changes in climate and to various important aspects of rabbit biology. In southern Queensland and subalpine New South Wales, quality of food in the stomach is less significantly related to changes in climate and the biological parameters measured.

Aa and Ab allotype frequencies have been investigated in wild rabbit populations throughout Victoria and South-east South Australia. The overall mean allele frequencies for thirty-three populations are 0-53:0-12:0-36 for a1:a2:a3 and 0-72:0-22:0-05 for b4:b5:b9. The b6 allele was not found anywhere. The a1 frequency has been found to increase in proportion to increases in mean annual rainfall. While considerable variations exist in allotype and allele frequencies from area to area, the relationships a1 greater than a3 greater than a2 and b4 greater than b5 greater than b9 are almost always observed. The results are discussed in terms of the historical origins of Australian wild rabbits and possible genetic mechanisms to explain the maintenance of allotype 'hierarchies' in large populations breeding at random.

Predation has usually been interpreted as being a compensatory mortality factor, removing only the doomed surplus. The literature on the wild Rabbit Oryctolagus cuniculus L. is reviewed to collate counter-evidence for a regulating influence of predation. This evidence is almost entirely circumstantial, not experimental. Predation has been reported to extend the length of time Rabbit populations remain low following a significant reduction of Rabbits by some other agent. Rabbit populations have been shown to increase very rapidly when predator density has suddenly been reduced. It has been suggested that predators affect the spread and dispersion of Rabbits both at the geographical and local levels. Predation has not, however, been shown to have an important influence at high Rabbit densities. Thus, its role can be that of a limiting factor rather than a density-dependent regulatory mortality factor. The concept of predator pressure is presented and discussed, pointing out that there is currently no standard technique used for its measurement. Further evidence on the importance of predation is presented from four recent studies in England and Wales that relate, by association, the distribution and abundance of local Rabbit populations to the local attitude towards predators. Rabbits were found to be significantly more widespread and abundant where predators were removed (not restricted to keepered game estates) or at low density, than when predators were undisturbed or at a high density. The significance of these results is discussed. The circumstantial and corroborative evidence leads strongly to the conclusion that predator pressure can act as an additive rather than compensatory mortality factor in some circumstances, and can thus be a potential regulating factor. Predation is more likely to be a limiting factor at low Rabbit density however, since a density-dependent relationship has not been demonstrated throughout the range of Rabbit densities that occur. This requires experimental demonstration to determine the threshold pressure below which predation becomes limiting. If so, reductions in Rabbit populations by short-term control operations could allow natural predation to help maintain low Rabbit densities for several years in some habitats. Conversely, the implications for Rabbit populations and thus crop damage resulting from predator control (e.g. in game management regimes) should be appreciated.

Seasonal variation in the Leydig cells and of the bulbourethral and prostate glands was studied in wild rabbits in southern Sweden, and the variation was correlated with an earlier description of the annual male fertility cycle. The full development of the testes and accessory reproductive organs in the spring was preceded by a peak in Leydig cell activity in January—February. After a depression around the summer solstice, the Leydig cell activity gradually increased, but spermatogenesis and the activity of the accessory reproductive organs continued to decline until late autumn.