Effects of group stability on aggression, stress and injuries in breeding rabbits

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

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

Effects of Genotype and Housing System on Rabbit Does' Aggressive Behaviors and Injuries in Smallholding Conditions

The objective of the study was to investigate the effects of housing (deep litter + concrete floor vs. deep litter + ground soil with the possibility to dig burrows), and genotype (Mecklenburg or Hyplus) on aggressive behaviour, social contacts, does' and kits' injuries, and progeny mortality. Twelve groups of six rabbit does (n = 72) were assigned to four treatments (two housing systems and two genotypes). Aggressive behaviour of does, number of injuries on does and kits, and postnatal kit mortality were recorded. The effects of housing and genotype were tested using multivariate GLMM Models. We found that the housing treatment in interaction with the genotype had a significant effect on aggressive behaviours in group housed does (F_3,12 = 14.34, p = 0.0003), where the lowest incidence of aggression was in Mecklenburg does housed on ground soil. Reduced aggression was reflected in a lower number of injuries in does (F_3,68 = 10.51, p < 0.0001), number of injuries in kits, and kit mortality (F_3,1 = 4.59, p < 0.0001, F_3,54 = 43.94, p < 0.0001). The results indicate that the proper combination of genotype and housing should be carefully considered for breeding to reduce aggression and injury in group housed does.

Levels of testosterone, progesterone and oestradiol in pregnant-lactating does in relation to aggression during group housing

The neuroendocrine regulation of rabbit maternal behaviour has been explored in detail. However, little is yet known about the hormonal regulation of aggression in concurrently pregnant-lactating does, a reproductive condition that prevails during group housing of rabbits on farms. Therefore, in this study we determined the relation between a) the levels of progesterone, testosterone, and oestradiol during lactation; b) the anogenital distance at artificial insemination; and c) the timing of grouping with the intensity of agonistic behaviour, published previously. We performed four consecutive trials, where three groups of eight does each were artificially inseminated on day 10 postpartum (pp) and grouped on either day 12, 18 or 22 pp. Using Dipetalogaster maxima, a reduviid blood-sucking bug, we collected blood samples during the pregnant-lactating phase (days 13, 15, 17, 19, 21, 23 pp) on one or two randomly chosen does per treatment group. Testosterone levels varied little across the pregnant-lactating phase, agreeing with results from pregnant-only rabbits, while progesterone levels increased from day 3 (=13 dpp) to day 7 (=17 dpp) and remained unchanged until day 13 (=23 dpp) of pregnancy. All oestradiol concentrations fell below the limit of detection. Overall, all concentrations were slightly lower in comparison to rabbit studies with pregnantonly does. The agonistic behaviour was not related to the respective hormonal concentrations at grouping. In conclusion, the time point of grouping does after artificial insemination (AI) in the semi-group housing system only had a weak influence on aggression and the hormonal profile did not indicate an optimum time for grouping.

Part-time grouping of rabbit does in enriched housing: effects on performances, injury occurrence and enrichment use

Collective housing is perceived as a possible way to improve rabbit welfare, especially among adult females, which are normally individually housed. Part-time group housing seems to allow a better balance between welfare and health than continuous group housing, but practical implementation and consequences for reproductive performance have not been extensively studied. The aim of this work was to compare weight, feed intake, litter size, injury occurrence, body integrity, and spatial location of female rabbits housed part-time in group housing (PGH group, n = 32) or housed individually (IH group, n = 8). Females were grouped by opening connecting hatches between four individual enriched cages (platform, wood stick and gnawing block). Collective housing started 12 days after artificial insemination and was interrupted at the 10th day (instead of the 15th day later as originally planned) due to high injury rates and severe injuries caused by fighting. The proportion of injured females increased from 25% on the first day of grouping to 63% on the 10th day. Female weight gain during the experiment was similar in the two groups. Litter size at weaning was 9% lower in the PGH group than in the IH group (9.2 vs 10.0, P < 0.01). Platform use was recorded in 32% of the observations and was the highest during the 2 weeks before weaning (46% and 47% of total observations, P < 0.05). During the grouping period, there were at least two females in the same housing unit in 59.4% of the cases, at least two females were located on the same level in 31.3% of the cases. In conclusion, connecting individual cages is an ergonomic solution for part-time group housing, but does not prevent fights for the establishment of a social hierarchy. This is detrimental to the health and body integrity of female rabbits.

Methods of Assessment of the Welfare of Shelter Cats: A Review

At any moment, there are millions of cats housed in foster care facilities for abandoned and stray animals for various reasons worldwide. Care, management and regulation among these facilities differ. Moreover, shelters can never substitute the full comfort of a good home for the animal, and the welfare of cats in shelters is a subject of discussion in many respects. Cats are animals sensitive to changes; for most of them, placement in a shelter is a stressful experience because of changes in routine, environment and the presence of other animals. Stress is reflected in changes in behaviour, causes fluctuations in physiological values and disrupts the immune system, which is a predisposition to the development or reactivation of disease. Evaluation of the presence and intensity of negative impacts is possible through the use of evaluation tools based on indicators that help set the environment and management of keeping so as to disrupt the quality of life as little as possible. Although a comprehensive and valid welfare tool that would evaluate animal-based and at the same time resource-based (or management-based) indicators of cats in shelters is not currently available, it is possible to use partial evaluation of individual welfare indicators to assess welfare. This review aims to provide the readers with an insight into current options of assessment of the welfare of cats in shelters with an emphasis on behavioural, physiological and health indicators with an application in both practical and scientific contexts.

Grouping of breeding rabbit does at different time points: effects on fertility, mortality and weight

<p>Semi-group housing in breeding does has been shown to reduce production and breeding success in comparison to single-housed animals. One reason for this reduction could be stress and aggression when grouping does only 2 d after artificial insemination. The aim of this study was to test different time points of grouping on fertility of does, body weight of both kits and does, and mortality rates. Hence, does were separated and housed individually one day before giving birth to their kits. The does were then artificially inseminated on day 10 postpartum (dpp) and regrouped according to the treatment (time point) on 12 (TG12), 18 (TG18), or 22 (TG22) dpp, respectively. In total, five trials with three groups pertaining to the three treatments (eight does per treatment group) were conducted. Non-pregnant does were replaced with pregnant does before each new trial (57 different does needed). Data were analysed with (generalised) linear mixed effect models and survival analysis. There were no significant differences in fertility, body weight<br />or mortality of does among the treatments. The average fertility rate (number of kindling events/number of artificial inseminations×100) was low (40.92%) and seasonal effects may have partially masked treatment effects, as most trials took place during winter. Likewise, the survival rate of kits was not influenced by the treatment (survival test: χ²=2.3, df = 2, <em>P</em> = 0.3). Body weight of the kits was also not affected by the time point of grouping (average weight: 447.70±46.42 g (TG12), 452.20±55.30 g (TG18) and 460.06±89.23 g (TG22); <em>P</em> = 0.33). In conclusion, grouping does at a later time point in the reproductive cycle did not show any significant improvement in the breeding or productive success in a Swiss semi-group housing system. An elongated separation from conspecifics did not enhance the welfare of semi-group housed rabbits.</p>

Assessing the Preference of Rabbit Does to Social Contact or Seclusion: Results of Different Investigations

Simple Summary

Many studies were developed to improve welfare of domestic rabbits and on the possibility to increase contacts between co-specifics using animal group housing. However, a lot of behavior disorder in rabbit does was reported. This study presents two experiments carried out, respectively, in Italy (experiment 1) and in Germany (experiment 2), to evaluate the does’ motivation towards social contact. The Italian trial was based on a choice of test cages to investigate the preferences of nulliparous rabbit does for contacts with co-specifics (in a group of four animals) or seclusion. The German trial tested a different group-housing system constituted of four does and their kits to evaluate the same behavioral aspect. Experiment 1 showed that the time spent in seclusion or in group was almost the same (49.61% vs. 50.39%, respectively) whereas, experiment 2 showed that female does with kits preferred to stay alone (71.90%) rather than in a group, probably due to a hierarchical response stimulation. Besides, it showed a different individual preference; not all does like to share space with the others. This study suggests the need to find a cage adapted to the different physiological phase of does, for example, with the possibility to modify it during the breed cycle.

Abstract

The aim of this study was to verify the motivation of rabbit does to social contact or seclusion. The results of two different research activities assessed in Italy (experiment 1) and Germany (experiment 2) through the use of motivational cages are reported. In experiment 1, only the average time of occupation of the group or seclusion zone was recorded of four nulliparous does, while, in experiment 2, the group-housing system provided space for does with kits and consisted of four single areas (nest boxes with individual electronic nest box recognition systems). Experiment 1 showed that does spent a similar amount of time in seclusion or in group (49.61% vs 50.39%, respectively). On the contrary, in experiment 2, does with kits appeared to prefer spending time alone (71.90%) rather than in groups. The presence of kits probably stimulates a hierarchical and aggressive response of the dominant does, with the low-ranking does staying secluded to avoid violent interactions. In fact, in each reproductive cycle, one doe did stay in the group area whereas the other three does used this area in different percentages of time. Further researches are needed to find a good combination of the cage with the does’ physiological phases.

Health and welfare of rabbits farmed in different production systems

The AGRI committee of the European Parliament requested EFSA to assess the welfare of rabbits farmed in different production systems, including organic production, and to update its 2005 scientific opinion about the health and welfare of rabbits kept for meat production. Considering reproducing does, kits and growing rabbits, this scientific opinion focusses on six different housing systems, namely conventional cages, structurally enriched cages, elevated pens, floor pens, outdoor/partially outdoor systems and organic systems. To compare the level of welfare in the different housing systems and rabbit categories, welfare impact scores for 20 welfare consequences identified from the literature were calculated, taking their occurrence, duration and severity into account. Based on the overall welfare impact score (sum of scores for the single welfare consequences), obtained via a 2‐step expert knowledge elicitation process, the welfare of reproducing does is likely (certainty 66–90%) to be lower in conventional cages compared to the five other housing systems. In addition, it is likely to extremely likely (certainty 66–99%) that the welfare of kits is lower in outdoor systems compared to the other systems and that the welfare is higher in elevated pens than in the other systems. Finally, it is likely to extremely likely (certainty 66–99%) that the welfare of growing rabbits is lower in conventional cages compared to the other systems and that the welfare is higher in elevated pens than in the other systems. Ranking of the welfare consequences allowed an analysis of the main welfare consequences within each system and rabbit category. It was concluded that for reproducing does, as well as growing rabbits, welfare consequences related to behavioural restrictions were more prominent in conventional cages, elevated pens and enriched cages, whereas those related to health problems were more important in floor pens, outdoor and organic systems. Housing in organic rabbit farming is diverse, which can result in different welfare consequences, but the overall welfare impact scores suggest that welfare in organic systems is generally good.

Aggressiveness, Mating Behaviour and Lifespan of Group Housed Rabbit Does

Simple Summary

Aggressiveness is a well-known trait in different animal species, including the European wild and domesticated rabbit. It is one of the main problems in group housing of rabbit does. The aim of the experiment was to investigate the frequency of aggressiveness and mating behaviour as well as the lifespan of does depending on their rank order. Dominance hierarchy developed during aggressive behaviour, i.e., fighting. In most cases the primary position in the rank order was clear. Mating activity was very high after assembling the groups. In addition to male–female mating, some female-female and female-male mounting was also observed, which could lead to pseudo-pregnancy. A second small peak of sexual activity was observed at the end of the hypothetical pseudo-pregnancy. Based on the results it can be concluded that aggressive behaviour is frequent in group housing systems which is contrary to animal welfare. Natural mating is not effective in group-housing systems.

Abstract

Aggressiveness is one of the main problems in group housing of rabbit does. The aim of the experiment was to investigate the frequency of aggressiveness and mating behaviour as well as the lifespan of does depending on group composition. The female and male rabbits were housed in one of the 7.7 m² pens (four females and one male per pen). Based on the ages of female rabbits two homogenous groups (HOM) were formed containing four 17-week-old females and two heterogeneous groups (HET) containing three 17-week-old and one 1-year-old female. Twenty-four-hour video recordings were taken during the first month after assembling the groups, and the aggressive actions (fights) and matings were counted. The lifespan was examined over a 200-day experimental period. On the day after assembling the groups the number of fights among does was high in HET group. The same aggressive behaviour only started a week later in HOM group, and some fights between females and the male were also observed. The daily peaks of aggressiveness were in the morning (after the light on) and in the evening (before and after the lights off). The primary position of females in the hierarchy was clear but sometimes no differences were detected among the subordinate females. The mortality of does was connected with their rank order. The number of matings was very high on the day of assembling the groups and a second small peak was observed at the end of the hypothetical pseudo-pregnancy. In addition to mating between male and females, female–female and female–male mounting was also observed. Despite of the small sample size it seems that aggressive behaviour is frequent in group housing systems, which is contrary to animal welfare. Natural mating is not effective in group-housing system.

Housing Rabbit Does in a Combi System with Removable Walls: Effect on Behaviour and Reproductive Performance

We evaluated the effects of two types of colony cages, in which rabbit does were always in a group (C1), and where they were in combi cages furnished with removable internal walls to allow both individual and grouphousing (C2), in addition to the control group (C: conventional individual cage), on welfare, reproductive performance, and global efficiency. Forty-eight New Zealand White nulliparous rabbit does underwent artificially insemination (AI) and were divided into three groups, and reared in the different systems for about 1 year. The reproductive rhythm provides AIs at weaning (30d). In the C1 system, does were continuously grouped, while in C2, walls were inserted four days before kindling and removed 1week after it (60% of the timesheet in group). Reproductive traits and behaviour were evaluated during the entire year. The behavioural observations were performed around days 7, 36, and 44, corresponding to the inclusion of the does in the maternal cages, the insertion of walls four days before kindling, and the removal of the walls 1week after parturition in the C2 group, respectively. The percentages of does with severe skin injuries and the distribution of the injuries on different parts of body were also registered. Does reared in conventional cages showed the greatest presence of stereotype behaviours, while the C1 group showed the highest (p < 0.05) incidence of aggressiveness after regrouping (attack, dominance features, and lower allo-grooming) in comparison to the C2 group (17% and 22%, in C2 and C1 does, respectively).Individually caged does achieved the best productive performance (sexual receptivity, fertility, kindling rate, and number of kits born alive and at weaning). The C1 group showed the lowest performance (p < 0.05), whereas C2 showed an intermediate one. Does housed in the combi cage (C2) had higher (p < 0.05) receptivity and fertility rates and higher numbers of kits born alive and at weaning (79.2% and 76.2%; 7.95 and 7.20, respectively) than the C1 group, but lower values (p < 0.05) than does that were individually housed.

A review of recent research outcomes on the housing of farmed domestic rabbits: reproducing does

<p>The housing of farmed animals is increasingly scrutinised by society and thereby subject to a change towards more animal-friendly systems. For rabbits, also kept as pets, there are no EC regulations regarding their housing under farming conditions. In many countries, studies have been carried out to improve their welfare and health under current and alternative housing systems. This paper reviews and integrates the research efforts made since the EFSA report in 2005 on reproducing rabbit does and provides some conclusions, where possible, with special emphasis on animal welfare according to the principles stated by the Welfare Quality® project, i.e. good housing, good health and appropriate behaviour. The use of an elevated platform provides greater opportunities for does and their kits to move, jumping up and down. Management and housing systems (especially flooring) must guarantee good hygienic conditions (all-in, all-out) and separation of the rabbits from their excreta for proper resting places, hygiene and health. Plastic floors and footrests and environmental enrichments (e.g. gnawing material) are also recommended. Continuous group housing systems for reproducing females have been definitively proven to challenge animal welfare by increased aggression and injuries among does and to kits. Part-time group housing systems have proven to have potential, but cannot yet be recommended in farms until major problems of aggression and injuries among animals are solved.</p>

Are combi parks just as useful as regular parks for fatteners for part-time group housing of rabbit does?

<p>Group housing of lactating rabbit does is desirable from a welfare standpoint, but agonistic behaviour can cause severe skin injuries, which are undesired for animal welfare. Park layout, creating hiding places and escape possibilities, may help redirect attention away from fighting, which could in turn help prevent skin damage. An experiment was performed to test whether more damaging behaviour would occur in a combi park (with nest box panels) after mixing, compared to a regular park for fatteners, as nest box panels would obstruct does when escaping aggressive interactions. In addition, the position of the PVC pipe underneath the platform differed between parks (longitudinal or transversal), resulting in different escape routes. Twenty-two parks were used, in which 5 does per park were grouped at 23 d of lactation until weaning at 36 d of lactation. Skin injuries were scored at 4 d after grouping and on the day before weaning. The presence of nest box panels in a combi park and the position of the PVC pipe underneath the platform did not affect the level of skin damage. Moderate to severe injuries were observed, mostly at the hind quarters, ears and head. Five to 6% of the does were severely injured (wounds). There was a positive relationship between the average skin injury per park at 4 d after grouping and at weaning. On average, average injury score per park increased from grouping to weaning, but there are differences between individual parks. From this experiment it can be concluded that group housing of lactating rabbit does involves animals getting injured. In fact, 5 to 6% of the does were severely injured (wounds). Social dynamics of group housed does are insufficiently understood and might be important to reduce damaging behaviour in group housing.</p>

Alternative and enriched housing systems for breeding does: a review

The main results and observations on group and individually housed rabbit does were reviewed by Szendrő and McNitt in 2012, but in recent years several new papers in this field have been published. This provides a new opportunity to summarise the current knowledge on alternative housing systems for breeding does. In Switzerland, rabbit does are generally housed in group systems. The recently legislated Belgian and Dutch housing systems will be converted step by step into group housing systems. Recent research demonstrated that with semi-group housing systems much better performance levels are possible than with the Swiss group housing system. However, solutions to eliminate aggression, stress and injuries which are common among rabbit does in group housing systems have yet to be found. Some authors are of the opinion that individual cages are too small and allow limited possibilities for movement and social contact. Positive results were seen when platforms were inserted into the cages and the possibility for movement increased. The does and their kits could jump up and down using the platforms. Using footrests, the incidence of sore hocks declined. Several environmental enrichments which increase the well-being of rabbit does can also be used. These enriched cages (equipped with platforms, footrests, gnawing sticks, etc.) are fully in line with animal welfare requirements. Increasing the size of cages and enriching them increases the production cost and the meat will be more expensive.