Until the early 1980s, it was totally unknown that lagomorphs were the hosts of several caliciviruses, which were included in the genus Lagovirus by the International Committee on Taxonomy of Viruses (ICTV) in 2000. In those years, two new diseases appeared, with very similar clinical and pathological profiles and associated high mortality rates: rabbit haemorrhagic disease (RHD) in rabbits and European Brown Hare Syndrome (EBHS) in European brown hares. It took a few years to ascertain that both diseases, actually acute and fatal forms of hepatitis, were caused by two genetically related caliciviruses, but they were finally classified by ICTV into two distinct viral species on the basis of their molecular characterisation and epidemiological data: RHDV in rabbit and EBHSV in brown hare. RHD has had a devastating effect on rabbit farms, causing great economic damage, especially in China, where RHD was first noticed around 1982, and in Europe. RHD has also severely affected wild rabbit populations, whose drastic decline has caused serious ecological imbalances in territories such as Spain, where rabbits are a central link in the wildlife food chain. Since the early 1990s, with the increased availability on the market of RHDV vaccines effective in protecting rabbits from RHD, the impact of the disease on rabbit farms has been significantly reduced. In the following years, also considering that RHDV is an endemic virus that cannot be eradicated, farmers learned how to manage the continuous use of RHDV vaccine in relation to the epidemiological situation, the type of breeding farm and the costs of vaccination prophylaxis. Although precarious, management of the RHD risk for rabbit farmers reached an acceptable equilibrium, which was, however, completely upset starting from 2010 by the emergence of another lagovirus also causing RHD. The genome of the newly emerged virus shows limited differences from that of RHDV, but the phenotypic traits of the two viruses are distinctive in at least three main respects: 1) The antigenic profile of the virus (the “face” of the virus recognised by the antibodies) is largely different from that of RHDV. 2) Newborn rabbits only a couple of weeks old die of RHD when infected with the new virus, while RHDV infections run asymptomatic until 7-8 wk of age. 3) The new virus, which started in Europe, has spread over the years to several continents, affecting wild and/or domestic rabbit populations. During this worldwide distribution, the new virus infected several lagomorph species and was shown to cause RHD in most of them. Considering these marked differences and the fact that the new virus is not a variant of RHDV, we proposed the name RHDV type 2 (RHDV2). All these main distinctive traits that differentiate RHDV from RHDV2 have the following consequences in practice: 1) The antigenic difference between RHDV and RHDV2 (their ‘faces’) is so great that we need “new” specific vaccines to control RHDV2 (i.e. RHDV2 is a new se
{"title":"Viral haemorrhagic disease: RHDV type 2 ten years later","authors":"L. Capucci, P. Cavadini, A. Lavazza","doi":"10.4995/wrs.2022.16505","DOIUrl":"https://doi.org/10.4995/wrs.2022.16505","url":null,"abstract":"Until the early 1980s, it was totally unknown that lagomorphs were the hosts of several caliciviruses, which were included in the genus Lagovirus by the International Committee on Taxonomy of Viruses (ICTV) in 2000. In those years, two new diseases appeared, with very similar clinical and pathological profiles and associated high mortality rates: rabbit haemorrhagic disease (RHD) in rabbits and European Brown Hare Syndrome (EBHS) in European brown hares. It took a few years to ascertain that both diseases, actually acute and fatal forms of hepatitis, were caused by two genetically related caliciviruses, but they were finally classified by ICTV into two distinct viral species on the basis of their molecular characterisation and epidemiological data: RHDV in rabbit and EBHSV in brown hare. RHD has had a devastating effect on rabbit farms, causing great economic damage, especially in China, where RHD was first noticed around 1982, and in Europe. RHD has also severely affected wild rabbit populations, whose drastic decline has caused serious ecological imbalances in territories such as Spain, where rabbits are a central link in the wildlife food chain. Since the early 1990s, with the increased availability on the market of RHDV vaccines effective in protecting rabbits from RHD, the impact of the disease on rabbit farms has been significantly reduced. In the following years, also considering that RHDV is an endemic virus that cannot be eradicated, farmers learned how to manage the continuous use of RHDV vaccine in relation to the epidemiological situation, the type of breeding farm and the costs of vaccination prophylaxis. Although precarious, management of the RHD risk for rabbit farmers reached an acceptable equilibrium, which was, however, completely upset starting from 2010 by the emergence of another lagovirus also causing RHD. The genome of the newly emerged virus shows limited differences from that of RHDV, but the phenotypic traits of the two viruses are distinctive in at least three main respects: 1) The antigenic profile of the virus (the “face” of the virus recognised by the antibodies) is largely different from that of RHDV. 2) Newborn rabbits only a couple of weeks old die of RHD when infected with the new virus, while RHDV infections run asymptomatic until 7-8 wk of age. 3) The new virus, which started in Europe, has spread over the years to several continents, affecting wild and/or domestic rabbit populations. During this worldwide distribution, the new virus infected several lagomorph species and was shown to cause RHD in most of them. Considering these marked differences and the fact that the new virus is not a variant of RHDV, we proposed the name RHDV type 2 (RHDV2). All these main distinctive traits that differentiate RHDV from RHDV2 have the following consequences in practice: 1) The antigenic difference between RHDV and RHDV2 (their ‘faces’) is so great that we need “new” specific vaccines to control RHDV2 (i.e. RHDV2 is a new se","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46266146","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}
In in the last 60 or so years, the global rabbit industry has been growing steadily. This paper studies the global rabbit meat trade by focusing on trade growth and regional pattern. First, rabbit meat productionand regional structure are introduced, as the basis of trade. Then, the global rabbit meat trade is studied in detail, including trade growth, regional structural changes, comparative advantages and competitiveness of major countries. Finally, a gravity model is built to test major factors affecting the rabbit meat trade andexplore the driving forces behind the trade. The data come from different channels, including the Food and Agriculture Organization of the United Nations, World Bank, the World Trade Organization and related government statistics. The results show that: (1) Over the past 60 yr, the global rabbit industry has achieved great progress. In the first half of the period, rabbit meat was mainly produced in Europe; then, rabbit meat production in Asia increased steadily and rapidly in the second half period, while European production decreased continuously. (2) The rabbit meat trade had been increasing for about 20 yr from 1961 to 1979, after which it fluctuated for another 20 yr. However, since 2001 it has been stable around an average level of 37 thousand tonnes, with only minor fluctuation. The trade pattern is currently from Asia (mainly China) and South America (mainly Argentina) to European countries. In 2018, the top 5 export destinations were Germany, Belgium, Italy, Portugal and France (3). Hungary and Argentina have been two strong competitorsin the last two decades, while Spain and Belgium are two new and promising countries in the rabbit meat trade. Now China no longer has comparative advantages in the rabbit meat trade (4). The gravity model results show that rabbit meat trade is mainly driven by demand. Countries with a high Gross Domestic Product tend to increase their imports more, but decrease their exports. Countries with higher populations export more rabbit meat but import less. Common language and contiguity of two countries have significant impacts on rabbit meat trade. Based on the above results, some suggestions and policy implications are provided. Rabbit farmers or processing companies should pay more attention to domestic consumers or neighbouring countries to survey potential markets; traders should explore more markets in order to reduce the degree of trade concentration and lower risks. Governments should popularise the nutritional knowledge of rabbit meat to encourage people (especially young people) to consume more healthy rabbit meat instead of pork, with a view to reducing obesity or other heart diseases, etc.
{"title":"Rabbit meat trade of major countries: regional pattern and driving forces","authors":"Laping Wu","doi":"10.4995/wrs.2022.13390","DOIUrl":"https://doi.org/10.4995/wrs.2022.13390","url":null,"abstract":"In in the last 60 or so years, the global rabbit industry has been growing steadily. This paper studies the global rabbit meat trade by focusing on trade growth and regional pattern. First, rabbit meat productionand regional structure are introduced, as the basis of trade. Then, the global rabbit meat trade is studied in detail, including trade growth, regional structural changes, comparative advantages and competitiveness of major countries. Finally, a gravity model is built to test major factors affecting the rabbit meat trade andexplore the driving forces behind the trade. The data come from different channels, including the Food and Agriculture Organization of the United Nations, World Bank, the World Trade Organization and related government statistics. The results show that: (1) Over the past 60 yr, the global rabbit industry has achieved great progress. In the first half of the period, rabbit meat was mainly produced in Europe; then, rabbit meat production in Asia increased steadily and rapidly in the second half period, while European production decreased continuously. (2) The rabbit meat trade had been increasing for about 20 yr from 1961 to 1979, after which it fluctuated for another 20 yr. However, since 2001 it has been stable around an average level of 37 thousand tonnes, with only minor fluctuation. The trade pattern is currently from Asia (mainly China) and South America (mainly Argentina) to European countries. In 2018, the top 5 export destinations were Germany, Belgium, Italy, Portugal and France (3). Hungary and Argentina have been two strong competitorsin the last two decades, while Spain and Belgium are two new and promising countries in the rabbit meat trade. Now China no longer has comparative advantages in the rabbit meat trade (4). The gravity model results show that rabbit meat trade is mainly driven by demand. Countries with a high Gross Domestic Product tend to increase their imports more, but decrease their exports. Countries with higher populations export more rabbit meat but import less. Common language and contiguity of two countries have significant impacts on rabbit meat trade. Based on the above results, some suggestions and policy implications are provided. Rabbit farmers or processing companies should pay more attention to domestic consumers or neighbouring countries to survey potential markets; traders should explore more markets in order to reduce the degree of trade concentration and lower risks. Governments should popularise the nutritional knowledge of rabbit meat to encourage people (especially young people) to consume more healthy rabbit meat instead of pork, with a view to reducing obesity or other heart diseases, etc.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47720765","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}
The Eastern cottontail (Sylvilagus floridanus) was an iconic game species during the mid-20thcentury in the United States. Game farms were set up to produce additional cottontail numbers for hunting purposes; however, for various reasons, many game farms were unable to propagate the necessary additional numbers of cottontails needed. The purpose of this paper is to review the landscape factors involved and offer recommendations on the importance of a landscape perspective with the use of game farms under a historical mid-20th century perspective. The results of this paper show that areas with more regional spatial scales and more than one game farm reared more cottontails and harvested than the single county, single game farm scenarios and soil for plant growth, topography and relief, and edges and boundaries of landscapes were some of the main landscape attributes that could have been important for the historical cottontail game farms. Further research could examine the number of game farms, suggestions for plot number and size, and landscape barriers to disturbance in order to help mitigate threats to cottontail game populations.
{"title":"What landscape aspects may have been important to Eastern cottontail (Sylvilagus spp.) game farms during the Mid-20th Century in the United States?","authors":"Kelsey Gilcrease","doi":"10.4995/wrs.2022.15908","DOIUrl":"https://doi.org/10.4995/wrs.2022.15908","url":null,"abstract":"The Eastern cottontail (Sylvilagus floridanus) was an iconic game species during the mid-20thcentury in the United States. Game farms were set up to produce additional cottontail numbers for hunting purposes; however, for various reasons, many game farms were unable to propagate the necessary additional numbers of cottontails needed. The purpose of this paper is to review the landscape factors involved and offer recommendations on the importance of a landscape perspective with the use of game farms under a historical mid-20th century perspective. The results of this paper show that areas with more regional spatial scales and more than one game farm reared more cottontails and harvested than the single county, single game farm scenarios and soil for plant growth, topography and relief, and edges and boundaries of landscapes were some of the main landscape attributes that could have been important for the historical cottontail game farms. Further research could examine the number of game farms, suggestions for plot number and size, and landscape barriers to disturbance in order to help mitigate threats to cottontail game populations.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46324069","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}
Further knowledge on aspects of social behaviour in the wild rabbit (Oryctolagus cuniculus), including the link to reproduction, could possibly point to new ways to improve housing and breeding conditions in rabbit farming. In this review, I present some results of our long-term study on a 2-hectare field enclosure population of wild rabbits (University of Bayreuth, Germany), exploring group-level and individual-level differences in agonistic behaviour of females and their potential associations with reproductive traits, including offspring survival. The frequency of agonistic behaviour in which females were involved, increased with increasing group size, and was lower in groups with a more heterogeneous age structure. At the individual level, reproducing females were involved in more agonistic interactions when groupmates gave birth and thus built their burrows and nests at around the same time, and higher-ranking mothers were particularly aggressive when other females approached close to their nursery burrows. Associations between females’ social environment and reproduction were evident, as the numbers of litters and offspring per female were lower at higher female densities, high-ranking females produced more offspring and had a lower offspring mortality than low-ranking ones, and cases of infanticide were lower in more stable groups, which we quantified by the more heterogeneous age structure of the females’ rank hierarchy in such groups. Furthermore, perinatal offspring mortality was increased in females with a delayed burrow and nest building activity, i.e. does that dug their nursery burrow and built their nest only during the last 24 h pre-partum, possibly driven by the more unfavourable social environment experienced by such females. Most importantly, our studies highlight the importance of the presence of litter siblings in improving an individual’s social environment, which resulted in an earlier onset of breeding in such females. Higher levels of positive social interactions with litter siblings were also associated with lower stress hormone (corticosterone) levels and with a better health status in terms of lower loads with an intestinal nematode. These findings on ameliorating effects of litter sibling presence in growing rabbits as well as in reproducing females may be a promising starting point worth further exploration in the context of group housing of domestic rabbits.
{"title":"Aspects of social behaviour and reproduction in the wild rabbit – Implications for rabbit breeding?","authors":"Heiko G. Rödel","doi":"10.4995/wrs.2022.15954","DOIUrl":"https://doi.org/10.4995/wrs.2022.15954","url":null,"abstract":"Further knowledge on aspects of social behaviour in the wild rabbit (Oryctolagus cuniculus), including the link to reproduction, could possibly point to new ways to improve housing and breeding conditions in rabbit farming. In this review, I present some results of our long-term study on a 2-hectare field enclosure population of wild rabbits (University of Bayreuth, Germany), exploring group-level and individual-level differences in agonistic behaviour of females and their potential associations with reproductive traits, including offspring survival. The frequency of agonistic behaviour in which females were involved, increased with increasing group size, and was lower in groups with a more heterogeneous age structure. At the individual level, reproducing females were involved in more agonistic interactions when groupmates gave birth and thus built their burrows and nests at around the same time, and higher-ranking mothers were particularly aggressive when other females approached close to their nursery burrows. Associations between females’ social environment and reproduction were evident, as the numbers of litters and offspring per female were lower at higher female densities, high-ranking females produced more offspring and had a lower offspring mortality than low-ranking ones, and cases of infanticide were lower in more stable groups, which we quantified by the more heterogeneous age structure of the females’ rank hierarchy in such groups. Furthermore, perinatal offspring mortality was increased in females with a delayed burrow and nest building activity, i.e. does that dug their nursery burrow and built their nest only during the last 24 h pre-partum, possibly driven by the more unfavourable social environment experienced by such females. Most importantly, our studies highlight the importance of the presence of litter siblings in improving an individual’s social environment, which resulted in an earlier onset of breeding in such females. Higher levels of positive social interactions with litter siblings were also associated with lower stress hormone (corticosterone) levels and with a better health status in terms of lower loads with an intestinal nematode. These findings on ameliorating effects of litter sibling presence in growing rabbits as well as in reproducing females may be a promising starting point worth further exploration in the context of group housing of domestic rabbits.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44517548","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}
The objective of the present study was to evaluate the influence of the genotypes of two single nucleotide polymorphisms (SNPs) – c.78C>T located in the growth hormone gene (GH) and c.106C>G in the growth hormone receptor gene (GHR) on individual body weight (IBW) during the growing period at 35, 70 and 90 d of age on a total of 107 weaned Californian breed rabbits. The restriction fragments obtained revealed that 74.8% of the rabbits carrying c.78C>T SNP and 52.3% of the rabbits carrying c.106C>G SNP were heterozygous, which indicated a moderate level of genetic diversity in this Californian population. Association analysis based on a single-gene approach revealed that c.78C>T polymorphism in the GH gene had a significant effect (P<0.05) on the weight at 70 and 90 d of age. The highest IBW (2530.4±66.6 g) was observed in rabbits carrying the c.78C>T TT genotype, and detected individuals were significantly affected by the dominance effect. Significant differences were observed between individuals with homozygous c.106C>G CC genotype and those with heterozygous CG genotype. The highest IBW (2462.0±198.3 g) was observed in rabbits carrying the c.106C>G CC genotype and detected individuals were significantly affected by the additive effect. A total of nine combined genotypes of c.78C>T and c.106C>G SNPs was found in the study, of which only four major groups (CT/CC, CC/CG, CT/CG, and CT/GG) were concerned in the diplotype analysis. Significant differences were observed between individuals with CT/CC and CC/CG genotype combinations, and between those with the CC/CG and CT/GG diplotypes. However, the highest IBW at 90 d of age (2447.2±213.8 g) was observed in rabbits carrying the CT/CC genotype combinations. The highest coefficient of determination found for individual body weight at 90 d of age (R2=10.8%) indicated a high effect of genotype combinations. In conclusion, the results obtained suggested that c.78C>T of GH gene and c.106C>G of GHR gene could be useful candidate genes to improve growth performance in Californian rabbits with potential application in rabbit breeding programmes.
本研究旨在评价生长激素基因(GH)中的c.78C>T和生长激素受体基因(GHR)中的c.106C>G两种单核苷酸多态性(snp)基因型对生长35、70和90日龄加利福尼亚种兔个体体重(IBW)的影响。限制性内切片段显示,携带c.78C>T SNP的家兔中有74.8%为杂合,携带c.106C>G SNP的家兔中有52.3%为杂合,表明该加利福尼亚人群具有中等水平的遗传多样性。基于单基因方法的关联分析显示,生长激素基因的c.78C>T多态性对PT TT基因型有显著影响,且检测个体受显性效应影响显著。纯合c.106C . > . G . CC基因型个体与杂合CG基因型个体间存在显著差异。携带c.106C> g CC基因型的家兔IBW最高(2462.0±198.3 g),且检测个体受加性效应影响显著。本研究共发现c.78C>T和c.106C >g snp的9个组合基因型,其中双倍型分析只涉及4个主要组(CT/CC、CC/CG、CT/CG和CT/GG)。CT/CC和CC/CG基因型组合个体之间、CC/CG和CT/GG基因型个体之间存在显著差异。然而,携带CT/CC基因型组合的家兔在90日龄时的体重最高(2447.2±213.8 g)。90日龄个体体重的决定系数最高(R2=10.8%),表明基因型组合的影响很大。综上所述,GH基因的c.78C>T和GHR基因的c.106C >g可能是提高加州家兔生长性能的候选基因,在家兔育种中具有潜在的应用价值。
{"title":"Association analysis of nucleotide polymorphisms in growth hormone (GH) and its receptor (GHR) with body weight in Californian rabbits","authors":"D. Gencheva, K. Velikov, P. Veleva","doi":"10.4995/wrs.2022.13127","DOIUrl":"https://doi.org/10.4995/wrs.2022.13127","url":null,"abstract":"The objective of the present study was to evaluate the influence of the genotypes of two single nucleotide polymorphisms (SNPs) – c.78C>T located in the growth hormone gene (GH) and c.106C>G in the growth hormone receptor gene (GHR) on individual body weight (IBW) during the growing period at 35, 70 and 90 d of age on a total of 107 weaned Californian breed rabbits. The restriction fragments obtained revealed that 74.8% of the rabbits carrying c.78C>T SNP and 52.3% of the rabbits carrying c.106C>G SNP were heterozygous, which indicated a moderate level of genetic diversity in this Californian population. Association analysis based on a single-gene approach revealed that c.78C>T polymorphism in the GH gene had a significant effect (P<0.05) on the weight at 70 and 90 d of age. The highest IBW (2530.4±66.6 g) was observed in rabbits carrying the c.78C>T TT genotype, and detected individuals were significantly affected by the dominance effect. Significant differences were observed between individuals with homozygous c.106C>G CC genotype and those with heterozygous CG genotype. The highest IBW (2462.0±198.3 g) was observed in rabbits carrying the c.106C>G CC genotype and detected individuals were significantly affected by the additive effect. A total of nine combined genotypes of c.78C>T and c.106C>G SNPs was found in the study, of which only four major groups (CT/CC, CC/CG, CT/CG, and CT/GG) were concerned in the diplotype analysis. Significant differences were observed between individuals with CT/CC and CC/CG genotype combinations, and between those with the CC/CG and CT/GG diplotypes. However, the highest IBW at 90 d of age (2447.2±213.8 g) was observed in rabbits carrying the CT/CC genotype combinations. The highest coefficient of determination found for individual body weight at 90 d of age (R2=10.8%) indicated a high effect of genotype combinations. In conclusion, the results obtained suggested that c.78C>T of GH gene and c.106C>G of GHR gene could be useful candidate genes to improve growth performance in Californian rabbits with potential application in rabbit breeding programmes.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41438462","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}
D. Wulandari, Indri Hermiyati, Iswahyuni Iswahyuni, A. Z. Tawarniate
This study aims to find out the effect of hydrochloric acid curing concentration on the characteristics of rabbit bone gelatin and determine the level of hydrochloric acid concentration for the soaking process to produce the best characteristics of rabbit bone gelatin. The material used was 50 kg of Rex rabbit bones obtained from rabbit farms, HCl 4, 5 and 6% and distilled water. The rabbit skin was soaked in hydrochloricacid (4, 5 and 6%) for 4 d as treatment and replicated three times. Gelatin extraction was performed three times at temperatures of 65, 75 and 85°C for 4 h each time and the results obtained were filtered through filter paper. The filtrate was concentrated at 50°C for 5 h. The concentrated filtrate was then poured into a tray before drying in an oven at 50°C until dry. Milling was carried out until it became gelatin powder. This study used a completely randomised design with a unidirectional pattern, and if there was a significant difference, continued with Duncan’s multiple range test. The results showed that the rabbit bone gelatin yield was between 6.18-8.52%, moisture 8.08-8.45%, ash content 8.15-10.93%, pH 3.85-4, protein content 57.09-62.84%, fat content 0.04-0.27%, gel strength 74.47-129.09 bloom, viscosity 3.06-4.26 cP, thick point 10-12°C, melting point 33-35°C and the molecular weights were 85, 120, and 212.5 kDa. The characteristics of rabbit bone gelatin still meet the Standar Nasional Indonesia gelatin range. Curing treatment with 6% HCl gave the best gelatin characteristics.
{"title":"Production and characterization of gelatin from rabbit bone as bioplastics material by acid pre-treatment","authors":"D. Wulandari, Indri Hermiyati, Iswahyuni Iswahyuni, A. Z. Tawarniate","doi":"10.4995/wrs.2022.16639","DOIUrl":"https://doi.org/10.4995/wrs.2022.16639","url":null,"abstract":"This study aims to find out the effect of hydrochloric acid curing concentration on the characteristics of rabbit bone gelatin and determine the level of hydrochloric acid concentration for the soaking process to produce the best characteristics of rabbit bone gelatin. The material used was 50 kg of Rex rabbit bones obtained from rabbit farms, HCl 4, 5 and 6% and distilled water. The rabbit skin was soaked in hydrochloricacid (4, 5 and 6%) for 4 d as treatment and replicated three times. Gelatin extraction was performed three times at temperatures of 65, 75 and 85°C for 4 h each time and the results obtained were filtered through filter paper. The filtrate was concentrated at 50°C for 5 h. The concentrated filtrate was then poured into a tray before drying in an oven at 50°C until dry. Milling was carried out until it became gelatin powder. This study used a completely randomised design with a unidirectional pattern, and if there was a significant difference, continued with Duncan’s multiple range test. The results showed that the rabbit bone gelatin yield was between 6.18-8.52%, moisture 8.08-8.45%, ash content 8.15-10.93%, pH 3.85-4, protein content 57.09-62.84%, fat content 0.04-0.27%, gel strength 74.47-129.09 bloom, viscosity 3.06-4.26 cP, thick point 10-12°C, melting point 33-35°C and the molecular weights were 85, 120, and 212.5 kDa. The characteristics of rabbit bone gelatin still meet the Standar Nasional Indonesia gelatin range. Curing treatment with 6% HCl gave the best gelatin characteristics.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48691149","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}
M. Braconnier, G. González-Mariscal, J. Wauters, S. Gebhardt-Henrich
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.
{"title":"Levels of testosterone, progesterone and oestradiol in pregnant-lactating does in relation to aggression during group housing","authors":"M. Braconnier, G. González-Mariscal, J. Wauters, S. Gebhardt-Henrich","doi":"10.4995/wrs.2021.14897","DOIUrl":"https://doi.org/10.4995/wrs.2021.14897","url":null,"abstract":"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.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48349029","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}
S. Mattioli, M. Maranesi, C. Castellini, A. Dal Bosco, M. Arias-Álvarez, P. Lorenzo, P. Rebollar, R. García-García
Rabbit is an induced ovulatory species, so ovulation takes place after mating. Traditionally, exogenous and synthetic hormonal factors (administered by intramuscular and intravaginal route) such as GnRH and analogues, or different physical procedures (i.e. stimulation by intravaginal cannula) have been used to induce ovulation in females when artificial insemination is applied in rabbit farms. Restriction and public rejection of the use of hormones is leading to the study of the seminal plasma components with potential action on ovulation induction. The aim of the present review is to collect and summarise the strategies used in recent years to trigger ovulation and improve rabbit fertility management with respect to more animal-friendly manipulation methods. Furthermore, special attention has been paid to the use of a semen component (as endogen molecule) such as beta nerve growth factor (β-NGF) in male and female rabbit reproductive physiology. This neurotrophin and its receptors (TrKA and p75NTR) are abundantly distributed in both male and female rabbit reproductive tracts, and it seems to have an important physiological role in sperm maturation and behaviour (velocity, apoptosis and capacitation), as well as a modulatory factor of ovulation. Endogen β-NGF is diluted in the seminal doses with the extenders; hence it could be considered an innovative and alternative strategy to avoid the current exogenous (by intramuscular route) and stressful hormonal treatments used in ovulation induction. Their addition in seminal dose could be more physiological and improve animal welfare in rabbit farms.
{"title":"Physiology and modulation factors of ovulation in rabbit reproduction management","authors":"S. Mattioli, M. Maranesi, C. Castellini, A. Dal Bosco, M. Arias-Álvarez, P. Lorenzo, P. Rebollar, R. García-García","doi":"10.4995/wrs.2021.13184","DOIUrl":"https://doi.org/10.4995/wrs.2021.13184","url":null,"abstract":"Rabbit is an induced ovulatory species, so ovulation takes place after mating. Traditionally, exogenous and synthetic hormonal factors (administered by intramuscular and intravaginal route) such as GnRH and analogues, or different physical procedures (i.e. stimulation by intravaginal cannula) have been used to induce ovulation in females when artificial insemination is applied in rabbit farms. Restriction and public rejection of the use of hormones is leading to the study of the seminal plasma components with potential action on ovulation induction. The aim of the present review is to collect and summarise the strategies used in recent years to trigger ovulation and improve rabbit fertility management with respect to more animal-friendly manipulation methods. Furthermore, special attention has been paid to the use of a semen component (as endogen molecule) such as beta nerve growth factor (β-NGF) in male and female rabbit reproductive physiology. This neurotrophin and its receptors (TrKA and p75NTR) are abundantly distributed in both male and female rabbit reproductive tracts, and it seems to have an important physiological role in sperm maturation and behaviour (velocity, apoptosis and capacitation), as well as a modulatory factor of ovulation. Endogen β-NGF is diluted in the seminal doses with the extenders; hence it could be considered an innovative and alternative strategy to avoid the current exogenous (by intramuscular route) and stressful hormonal treatments used in ovulation induction. Their addition in seminal dose could be more physiological and improve animal welfare in rabbit farms.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46979756","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}
Successful rabbit production relies heavily on the use of adequate practices that enhance specific aspects of reproduction, such as mating, ovulation and lactation. Regardless of the type of production unit or strain of rabbits used, these processes rely on a complex chain of neuroendocrine steps that include particular hormones, peripheral stimuli and activation of discrete brain regions. Such is the case, for instance, of reflex ovulation, which occurs in response to copulation but is inhibited throughout lactation. Little is known about the mechanisms mediating lactational anoestrus and the restoration of oestrus following the cancellation of a single suckling episode (biostimulation). Nevertheless, the latter procedure (adopted worldwide to accelerate reproduction) has unwanted consequences for the doe and her litter. After successive episodes of biostimulation, the former shows a loss of fertility and body mass. In the kits, alterations are observed in their neuroendocrine response to mildly aversive stimulation in adulthood, as well as reductions in sexual behaviour. In addition to milk intake, a good nest is essential for normal litter growth and development. If this is not available, or if it deteriorates, rabbit caretakers can easily (re) build one from hair sheared off other rabbits or using synthetic material. Lactating does will nurse equally well their own or ‘alien’ young, placed inside the nest. It is crucial to have a minimum of six suckling kits in the nest, as the doe relies on this stimulation to maintain a normal nursing behaviour, i.e., only once a day throughout lactation. Recent work is revealing the similarities and differences in the responsiveness to mating among oestrous, lactating and biostimulated does. The relevance of these findings for the likelihood of reflex ovulation and the additional contribution of factors contained in the semen warrant more in-depth research. New insights on these issues, essential to reproductive neuroendocrinology, can emerge by fostering a richer interaction between academic laboratories and rabbit production settings worldwide.
{"title":"Neuroendocrinology applied to rabbit breeding","authors":"G. González-Mariscal","doi":"10.4995/wrs.2021.12952","DOIUrl":"https://doi.org/10.4995/wrs.2021.12952","url":null,"abstract":"Successful rabbit production relies heavily on the use of adequate practices that enhance specific aspects of reproduction, such as mating, ovulation and lactation. Regardless of the type of production unit or strain of rabbits used, these processes rely on a complex chain of neuroendocrine steps that include particular hormones, peripheral stimuli and activation of discrete brain regions. Such is the case, for instance, of reflex ovulation, which occurs in response to copulation but is inhibited throughout lactation. Little is known about the mechanisms mediating lactational anoestrus and the restoration of oestrus following the cancellation of a single suckling episode (biostimulation). Nevertheless, the latter procedure (adopted worldwide to accelerate reproduction) has unwanted consequences for the doe and her litter. After successive episodes of biostimulation, the former shows a loss of fertility and body mass. In the kits, alterations are observed in their neuroendocrine response to mildly aversive stimulation in adulthood, as well as reductions in sexual behaviour. In addition to milk intake, a good nest is essential for normal litter growth and development. If this is not available, or if it deteriorates, rabbit caretakers can easily (re) build one from hair sheared off other rabbits or using synthetic material. Lactating does will nurse equally well their own or ‘alien’ young, placed inside the nest. It is crucial to have a minimum of six suckling kits in the nest, as the doe relies on this stimulation to maintain a normal nursing behaviour, i.e., only once a day throughout lactation. Recent work is revealing the similarities and differences in the responsiveness to mating among oestrous, lactating and biostimulated does. The relevance of these findings for the likelihood of reflex ovulation and the additional contribution of factors contained in the semen warrant more in-depth research. New insights on these issues, essential to reproductive neuroendocrinology, can emerge by fostering a richer interaction between academic laboratories and rabbit production settings worldwide.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47367505","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}
Yayu Huang, J. Breda, D. Savietto, A. Debrusse, J. M. Bonnemère, T. Gidenne, S. Combes, L. Fortun-Lamothe
This study investigated the effect of housing enrichments (scratching card, gnawing material and a platform), of a change in height and in the type of flooring on the live weight, reproductive performance and behaviour of female rabbits, as well as on the feed intake and spatial distribution of females and their kits. A total of 40 multiparous female rabbits were monitored in three consecutive reproductive cycles (48-d intervals). Four days before parturition in each reproductive cycle, the females were randomly assigned to one of the five types of housing: Control (CNT: 102×47×30 cm, L×W× H); Scratching card (SCT: containing a scratching card); Gnawing materials (GNW: CNT dimensions plus a compressed lucerne hay block and a wooden stick); Platform (PLT: 102×47×60 cm, including a platform with a plastic floor) and Combination (CBN: PLT dimensions with the scratching card, the gnawing materials and a platform). Data were only recorded during the first and third reproductive cycles. The living conditions did not significantly alter the females’ live weight (4889 g at housing; 4890 g at mid-lactation; 4867 g at weaning), reproductive performance (9.0 kits born alive), survival of the kits (90%), nor the feed intake of females and their litters (542 g/day). Providing animals with a gnawing block stimulated Gnawing behaviour (median frequency per group: CTL=0.00, SCT=0.00, GNW=4.69, PLT=0.00, and CBN=2.34; PRearing up behaviour (median frequencies per group: CTL=0.00, SCT=0.00, GNW=0.00, PLT=2.08, and CBN=3.12; P=0.06), and when a platform was present, the rabbits used it (mean values per group: CTL=0.00, SCT=0.00, GNW=0.00, PLT=1.79, and CBN=4.91; P=0.003). Regarding the type of floor, females appeared to prefer the plastic mesh flooring (31.2%) to the wire mesh flooring (18.8%). To sum up, providing female rabbits with simple enrichments appears to stimulate specific behaviours like Gnawing and Rearing up and may contribute to their wellbeing.
{"title":"Effect of housing enrichment and type of flooring on the performance and behaviour of female rabbits","authors":"Yayu Huang, J. Breda, D. Savietto, A. Debrusse, J. M. Bonnemère, T. Gidenne, S. Combes, L. Fortun-Lamothe","doi":"10.4995/wrs.2021.15848","DOIUrl":"https://doi.org/10.4995/wrs.2021.15848","url":null,"abstract":"This study investigated the effect of housing enrichments (scratching card, gnawing material and a platform), of a change in height and in the type of flooring on the live weight, reproductive performance and behaviour of female rabbits, as well as on the feed intake and spatial distribution of females and their kits. A total of 40 multiparous female rabbits were monitored in three consecutive reproductive cycles (48-d intervals). Four days before parturition in each reproductive cycle, the females were randomly assigned to one of the five types of housing: Control (CNT: 102×47×30 cm, L×W× H); Scratching card (SCT: containing a scratching card); Gnawing materials (GNW: CNT dimensions plus a compressed lucerne hay block and a wooden stick); Platform (PLT: 102×47×60 cm, including a platform with a plastic floor) and Combination (CBN: PLT dimensions with the scratching card, the gnawing materials and a platform). Data were only recorded during the first and third reproductive cycles. The living conditions did not significantly alter the females’ live weight (4889 g at housing; 4890 g at mid-lactation; 4867 g at weaning), reproductive performance (9.0 kits born alive), survival of the kits (90%), nor the feed intake of females and their litters (542 g/day). Providing animals with a gnawing block stimulated Gnawing behaviour (median frequency per group: CTL=0.00, SCT=0.00, GNW=4.69, PLT=0.00, and CBN=2.34; PRearing up behaviour (median frequencies per group: CTL=0.00, SCT=0.00, GNW=0.00, PLT=2.08, and CBN=3.12; P=0.06), and when a platform was present, the rabbits used it (mean values per group: CTL=0.00, SCT=0.00, GNW=0.00, PLT=1.79, and CBN=4.91; P=0.003). Regarding the type of floor, females appeared to prefer the plastic mesh flooring (31.2%) to the wire mesh flooring (18.8%). To sum up, providing female rabbits with simple enrichments appears to stimulate specific behaviours like Gnawing and Rearing up and may contribute to their wellbeing.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":null,"pages":null},"PeriodicalIF":0.8,"publicationDate":"2021-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46363170","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}