R. Belabbas, I. Ilès, M. Argente, Rym Ezzeoug, Hacina Ainbaziz, M. García
{"title":"Environmental and genetic factors affecting litter size components in rabbits","authors":"R. Belabbas, I. Ilès, M. Argente, Rym Ezzeoug, Hacina Ainbaziz, M. García","doi":"10.4995/wrs.2023.18680","DOIUrl":"https://doi.org/10.4995/wrs.2023.18680","url":null,"abstract":"In rabbits, ovulation rate is, together with prenatal survival, one of the main limiting factors for litter size. Both components are affected by several factors related to females and their environment. Thus, understanding these components and their factors of variation is key in designing diets, optimisation of reproductive performance and genetic selection. In this review, authors summarise the main components of litter size and their environmental factors of variation. Genetic factors and the main results of genetic selection programmes on components of litter size are also summarised. In this regard, a negative effect of dietary restriction and reduced day light hours is found, as well as a positive effect of body condition, parity order and age of female on ovulation rate. However, an increase in deterioration of oocyte quality has been reported as ovulation rate increases, leading to decreased embryonic and foetal survival. Dietary restriction and heat stress also have a negative effect on embryonic and foetal survival, increasing the failures during gestation while good vascularisation and enough available space in uterine horn are keys to embryonic and foetal survival. Ovulation rate was proposed as indirect selection criterion to improve litter size due to higher heritability. However, this selection was relevant, but it did not modify litter size because of an increase in prenatal mortality. Uterine capacity has been directly related to prenatal survival, although its selection has also been unsuccessful in increasing litter size.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47621406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Vicente, M. P. Viudes-de-Castro, F. Marco-Jiménez
{"title":"In vivo rabbit embryo production and cryopreservation review. Application to ex situ conservation and rederivation","authors":"J. Vicente, M. P. Viudes-de-Castro, F. Marco-Jiménez","doi":"10.4995/wrs.2023.18412","DOIUrl":"https://doi.org/10.4995/wrs.2023.18412","url":null,"abstract":"The development of reproductive technologies in this species is contributing decisively to the development of rabbit farming and the preservation of genetic resources. Obtaining embryos is an essential step to both genetic diffusion and the preservation of genetic resources from genetic erosion or natural disasters. In rabbits, it is common for embryos to be recovered post-mortem after ovarian hyperstimulation with gonadotrophins, although the quality and number of embryos are variable, affecting the embryo viability and offspring rate by the donor. In vivo embryo production within a conservation programme aims not only to obtain a large number of embryos, but also that they come from a greater number of male and female origins, in order to ensure an adequate representation of the original population. This is why both the quality and quantity of embryos obtained per donor rabbit and the rate of donors with offspring after embryo cryopreservation must be considered, as well as the response of the embryos to the chemical, physical and physiological stress to which they are subjected in the rederivation process and its postnatal repercussions on those that survive. Rederived rabbits from cryopreserved and transferred embryos showed phenotypic growth changes, which calls into question the neutrality of the technique and its usefulness in those cases in which a control population is required.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48130905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Trends in rabbit insemination extenders for fresh and frozen semen. A review","authors":"M. P. Viudes-de-Castro, J. Vicente","doi":"10.4995/wrs.2023.18505","DOIUrl":"https://doi.org/10.4995/wrs.2023.18505","url":null,"abstract":"Artificial insemination (AI) has become a popular technique in rabbit farms worldwide. This report discusses the progress made on semen extenders used in rabbit AI, setting out the latest innovations. Fresh and frozen semen have different requirements, so the extender composition will vary depending on the type of semen used. We discuss the endocrine supplementation of extenders for ovulation induction, the use of active molecules as an alternative to conventional antibiotics and the extenders developed for rabbit sperm cryopreservation.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45878104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Belabbas, Rym Ezzeroug, M. García, A. Berbar, G. Zitouni, Djamel Taalaziza, Zoulikha Boudjella, Nassima Boudahdir, Samir Dis, M. Argente
{"title":"Prenatal factors affecting the probability of survival between birth and weaning in rabbits","authors":"R. Belabbas, Rym Ezzeroug, M. García, A. Berbar, G. Zitouni, Djamel Taalaziza, Zoulikha Boudjella, Nassima Boudahdir, Samir Dis, M. Argente","doi":"10.4995/wrs.2023.18268","DOIUrl":"https://doi.org/10.4995/wrs.2023.18268","url":null,"abstract":"The aim of this study was to analyse the relationships between kit birth weight and litter size with kit survival from birth to weaning, and to estimate the effects of place of birth, nest quality, cannibalism, lactation, parity order, season and sex. A total of 1696 kits from 82 females of the ITLEV2006 synthetic line were used in this study. A logistic regression was performed. Kit birth weight was directly related to the probability of the kit’s survival from birth to weaning, and increasing birth weight by one gram increased the likelihood of kit survival by 8% to 10% (P<0.001). In line with the decrease in birth weight of kits as the number of kits at birth increases, litter size showed a negative relationship to the probability of survival from birth to weaning, and increasing the litter by one kit at birth decreased the probability of survival of the kits by 5% to 9% (P<0.05). Regarding effects, cannibalism events in the litter decreased the probability of survival of the kits in the first week of life (P<0.01). Being born in the cage decreased the probability of survival of the kits from birth to weaning, and kits born outside the nest had a lower chance of survival than those born inside the nest (P<0.01). The order of parturition had a positive effect on probability of survival of the kits from 5 days of age to weaning (P<0.05). Female kits had a lower chance of survival than male kits, but only until 5 days of age (P<0.01). The lactation status displayed a negative effect on the probability of survival of the kits in the first week of life, and kits gestated in lactating females had a lower chance of survival than those gestated in non-lactating females (P<0.05). In conclusion, the probability of kit survival in the first days after parturition was affected mainly by its weight at birth, litter size, cannibalism events, place of birth of kit, parity order, sex and lactation status, while the probability of kit survival at weaning was directly related to its weight at birth, litter size, place of birth of kit and parity order.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44116845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Gayrard, A. Bretaudeau, P. Gombault, H. Hoste, T. Gidenne
{"title":"Use of dehydrated sainfoin in rabbit feeding. Effects of a moderate dietary incorporation on performance and health of does and growing rabbits under an optimal farming environment","authors":"C. Gayrard, A. Bretaudeau, P. Gombault, H. Hoste, T. Gidenne","doi":"10.4995/wrs.2023.17734","DOIUrl":"https://doi.org/10.4995/wrs.2023.17734","url":null,"abstract":"The effects of a moderate incorporation of dehydrated sainfoin Perly cultivar (DS) in rabbit feeds on the performance and health of reproductive and growing rabbits were analysed over two consecutive reproductive cycles in a professional breeding environment. Two groups of 192 does and associated litters were fed isonutritive feeds containing either 0 or 13% dehydrated sainfoin (respectively C (control) vs. S (“sainfoin”) groups) in replacement mainly of dehydrated alfalfa. Growing rabbit feeds C and S included 0 and 15.6% safoin, respectively. Doe live weight, number of live rabbits at birth and stillborn rate were not affected by dietary DS incorporation. In cycle 1, fertility rate was 10% higher for the S-group, but was similar among the groups in the 2nd cycle (significant interaction). Incorporation of DS had no impact on kit growth before weaning, but improved the post-weaning growth rate by 6% (P<0.001) and the feed conversion ratio by 7%. Dietary DS incorporation had no effect on doe mortality, which was very low (<2%, P=0.07). Doe culling was half lower with sainfoin incorporation in cycle 1 (25% in group C vs. 12% in group S; P<0.05). In cycle 2, doe culling rate was low (3.2%) and similar among diets (significant interaction between diet and cycle effects). Pre-weaning mortality of kits was low and slightly higher for S-group (1.1 vs. 1.5%). Post-weaning mortality was also low and was reduced with sainfoin dietary incorporation (3.0 vs. 1.8%; P<0.001). A moderate incorporation of dehydrated sainfoin can be recommended for growing rabbits and for reproducing does feeds.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45931730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Abstracts of the VII American Rabbit Congress. Varadero, Cuba, 12th-13th October, 2022","authors":"Abstracts, Conferences, Congresses, Symposiums...","doi":"10.4995/wrs.2023.18932","DOIUrl":"https://doi.org/10.4995/wrs.2023.18932","url":null,"abstract":"Last October 12 and 13, 2022, the VII American Rabbit Congress took place within the framework of the 2022 Animal Production and Agro-Development Convention, which was held from October 10 to 14, 2022 at the Plaza América Convention Center in Varadero, Matanzas, Cuba. The VII American Rabbit Congress was developed in a hybrid way (in person and online) with specialists, researchers, professors, students, breeders and producers from different latitudes related to rabbit farming and science. Throughout the conference, a total of 50 people attended in person and 15 online, mainly from Cuba, Mexico, Argentina and Spain. The objective of the meeting was to \"Motivate the exchange of experiences and results in rabbit production systems in the Americas, their technical, economic, environmental and social sustainability, and strategies for the improvement, conservation, use and characterization of animal genetic resources\" for rabbit farming. The congress opened with a lecture by Juan José Pascual, president of the World Rabbit Science Association (WRSA) on the current state of rabbit farming, followed by three other invited lectures, 18 scientific communications, and a round table on viral hemorrhagic disease, as well as a total of 21 posters. These scientific contributions were directed both to the fundamental areas of knowledge (feeding, genetics, reproduction, pathology), but also to other important aspects of America such as socioeconomics, the value chain, and the use of rabbit farming as a tool to fight against hunger. During the first working day, aspects of the vertical integration of rabbit production, the production and commercialization of rabbits in Cuba, feeding costs and limitations for obtaining raw materials, concern for not total slaughtering rabbits where the virus outbreaks occurred, the political will to eradicate this disease and increase the productivity of the species, the components of the value chains and the need for a correct articulation between all the links in the chain were discussed. On the other hand, during the second working day, there was a debate mainly on aspects related to the role of rabbit farming in society, not only for the production of quality meat, but also for its gender approach, the use of existing local resources in the Latin American countries, and the positive experiences of producers in the promotion of rabbit breeding. The congress closed with good attendance in the room, with a representation of students, producers, specialists, researchers and representatives of state production units and the Cuban Ministry of Agriculture (Director of the National Center for Animal Health and President of the livestock business group).","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45399574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measuring the economic performance of small-scale rabbit production agribusiness enterprises","authors":"Ridwan Mukaila","doi":"10.4995/wrs.2023.18660","DOIUrl":"https://doi.org/10.4995/wrs.2023.18660","url":null,"abstract":"Reducing malnutrition and poverty remains at the centre of policy. Rabbit rearing, of great economic importance, is a critical pathway to achieving this. Good knowledge of the profitability of rabbit production and its driving factors can enhance participation in rabbit production. Thus, this study examined the economic performance (profitability) of rabbit production, the factors influencing profitability and its barriers. Descriptive statistics, profitability analysis, the Tobit regression model and Garret ranking were employed to achieve the objectives. The results indicated that rabbit production was economical, productive and profitable, with a gross margin of N675,990 (USD 1,633.5), a net income of N663,974 (USD 1,604.4), a profit ratio of 0.6, a benefit-cost ratio of 2.7, a return on capital invested of 1.7 and an operating ratio of 0.4. The factors that enhanced rabbit production profitability were stock size, education, experience, membership of the association and labour availability, whereas mortality, disease outbreaks and feeding costs were inhibiting factors to profitability. The major constraints affecting rabbit production are disease, a high mortality rate and poor access to credit. These call for the provision of disease management training and credits to motivate people to engage in rabbit farming, which will, in turn, lower poverty and increase protein availability.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47708577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Liesbeth G. W. Van Damme, E. Delezie, L. Maertens, B. Ampe, F. Tuyttens
{"title":"Effect of group size and escape enrichment on reproductive performance of breeding does in part-time group housing","authors":"Liesbeth G. W. Van Damme, E. Delezie, L. Maertens, B. Ampe, F. Tuyttens","doi":"10.4995/wrs.2023.18616","DOIUrl":"https://doi.org/10.4995/wrs.2023.18616","url":null,"abstract":"Societal demands for group housing of social farm animals such as rabbits are increasing due to animal welfare concerns. When breeding does are housed in groups, maternal protective behaviour negatively affects the reproductive performance of the does. In part-time group housing, does are housed in single-litter cages starting shortly before parturition until the first part of lactation and then group housed for the second part after their protective behaviour has diminished and the kits are more resilient. The aim of this study was to evaluate the reproductive performance of breeding does in a part-time group housing system with provision of escape enrichment and different group size (and concomitant different stocking density, as pen size remained unchanged). For each of the four consecutive reproductive cycles, 42 does with their kits switched at 22 d post-partum (pp) from single-litter to group housing for a total period of 13 d in pens of 200×102 cm by removing walls between four adjacent single-litter cages. Newly created group pens (N =12 pens per treatment) varied in group size, stocking density and enrichment: groups of either three or four does were divided over same-size pens with or without escape enrichment (2×2 factorial design). The escape enrichment was comprised of two sets of PVC pipes and two extra elevated platforms. Does were weighed and kits counted at parturition, after which kits were cross-fostered. Kits were counted and weighed again 22 and 35 d pp. Results for mean doe fertility (90.0%), number of kits (9.1 kits/litter) and kit weight (1037.3 g/kit) at weaning were comparable with professional farms using single-litter cages. No significant effects of group size and escape enrichment were found for any of the reproductive parameters. While housed in group, seven does were removed from the experiment, from which four does were severely injured. Post-grouping kit mortality was rather low (6.7%), but three kits were euthanised due to severe injuries. In conclusion, provision of escape enrichment and altered group size (and stocking density) had no profound effect on the reproductive performance of part-time group housed does.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48718212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anne-Sophie Plagnet, C. Bannelier, V. Fillon, D. Savietto
{"title":"Estimation of grass biomass consumed by rabbits housed in movable paddocks","authors":"Anne-Sophie Plagnet, C. Bannelier, V. Fillon, D. Savietto","doi":"10.4995/wrs.2023.18243","DOIUrl":"https://doi.org/10.4995/wrs.2023.18243","url":null,"abstract":"Biomass allowance is a key feature in pasture-based rabbit production systems. It conditions not only the stock density (rabbits/m²) and/or the number of grazing days, it also influences the grazing behaviour of animals. When herbage restriction occurs, pelleted feed and/or cereal intake goes up. Inadequate pasture management may also impair the biomass quantity and quality if overgrazing occurs. To avoid the undesirable effects of overgrazing and better manage pellet and cereal intake, information on both biomass availability and rabbits’ grazing capacity are needed. Here, we present an adaptation of the rising plate meter method (developed for biomass intake measures for ruminants) for use in rabbit. To this end, we designed an experiment where two groups of 12 rabbits each were kept in two different fields: under an apple orchard (AO) or on fallow land (FL). We followed the animals for 5 consecutive weeks (from 45 to 80 d old). Rabbits lived in 25 m² movable paddocks, and every week a new paddock location (called paddock-spot) was made available for them. At each new paddock-spot, we measured the herbage height inside the paddocks and performed samplings of the available biomass (i.e. herbage cut after herbage height measurement) outside the paddocks. From this data we estimated the available biomass inside each paddock-spot by fitting linear regression equations of biomass to herbage height. Overall, rabbits in the AO and FL had access to 1328±65.7 and 1386±58.6 kg of dry matter (DM) per ha, respectively. In every field and paddock-spot, the biomass available was lower than the rabbits’ grazing capacity; overgrazing was the rule. Roughly, and under a restricted herbage allowance, rabbits in the AO ingested 45.2 g DM/d and rabbits in the FL 43.4 g DM/d. In the last week (64 to 80 d old), the biomass intake of rabbits in the AO and AL represented 26.4 and 23.5% of the total DM intake, respectively. These values, however, does not represent the real grazing capacity of growing rabbits. In this study, we provide some advice on the sampling method to obtain reliable biomass estimations and we mention two methods for handling influential observations in linear regression.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41836900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yun Zhou, Xu Yuan, X. Hu, Shan-shan Yang, S. Zhong, Ting-Yu Yang, Guohua Zhao, Yingsong Jiang, Yong Li
{"title":"Changes of oxidant-antioxidant parameters in small intestines from rabbits infected with E. intestinalis and E. magna","authors":"Yun Zhou, Xu Yuan, X. Hu, Shan-shan Yang, S. Zhong, Ting-Yu Yang, Guohua Zhao, Yingsong Jiang, Yong Li","doi":"10.4995/wrs.2022.17395","DOIUrl":"https://doi.org/10.4995/wrs.2022.17395","url":null,"abstract":"Rabbit coccidiosis is a very serious disease caused by protozoan parasites of the genus Eimeria, which increases the production rate of free radicals, especially reactive oxygen species. When the generation of free radicals exceeds the scavenging capacity of the body’s antioxidant system, the oxidant-antioxidant balance is broken, resulting in oxidative stress. This study was designed to investigate the effect on the oxidant-antioxidant status of rabbits infected with E. intestinalis and E. magna. To this end, eighteen 30-d-old weaned rabbits were randomly allocated into three groups as follows: the E. intestinalis infection group with 3×103 sporulated oocysts of E. intestinalis, the E. magna infection group with 20×103 sporulated oocysts of E. magna, and the uninfected control group. We measured the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) and the contents of malondialdehyde (MDA) in rabbits’ small intestinal tissues (duodenum, jejunum and ileum) of the three groupson day 8. The results showed that CAT activity and MDA levels significantly increased, while the activities of SOD, GSH-Px and T-AOC decreased after E. intestinalis and E. magna infection. Besides, the jejunum and ileum were particularly damaged in the rabbits. It is concluded that the pathological oxidative stress occurs during the E. intestinalis and E. magna infection process and the body’s oxidant-antioxidant balance is disrupted.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2022-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49601576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}