Anne-Sophie Larivière-Lajoie, D. Cinq-Mars, Frédéric Guay, Simon Binggeli, Antoni Dalmau, Linda Saucier
This study aimed to characterise the quality of meat from commercially-raised rabbits. Animals came from five different producers and were laughtered in three different plants under provincial or federal inspection jurisdiction. Animal behaviour evaluated by scan sampling prior to feed withdrawal (FW) and transport, as well as blood lactate concentration at exsanguination, did not raise concerns with respect to stress. Stomach pH was higher (P=0.047) when the FW time was short (≤13.5 h), at a mean value of 2.23. All pH values measured 1 h post-mortem from the Biceps femoris (BF) and almost all (97.6%) from the Longissimus lumborum (LL) were higher than 6. Values for ultimate pH measured 24 h postmortem(pHu) ranged from 5.80 to 6.83 and from 5.70 to 6.70 for BF and LL muscles, respectively. The maximum meat drip loss recorded was 2.6%, while cooking loss reached 30%. Meat lightness (L*) and colour intensity (C*) for the long FW times (≥23 h) were no different from those with short and intermediate (15.5 to 17.3 h) FW times. However, these colour parameters were higher for the short FW time class compared to the intermediate FW time class (P<0.02). A hierarchical cluster analysis based on pHu, cooking loss and lightness (L*) from 200 rabbit loins was performed. Of the four clusters created, clusters 1 and 2 had the best and second-best meat quality, respectively. Clusters 3 and 4 had the lowest meat quality and presented DFD-like (dark, firm and dry) characteristics. Meat did not exhibit PSE-like (pale, soft, exudative) characteristics, even for the slaughter lot with the minimum mean pHu. Of the eight slaughter lots evaluated, more than 50% of the meat from three of them fell into clusters 3 and 4; all three were in the intermediate FW time class. Overall, the quality of rabbit meat analysed was acceptable for commercial use, but rather variable. This suggests that there are factors within the value chain that are not yet fully controlled and require further investigation.
{"title":"Hierarchical clustering as a tool to develop a classification scheme for rabbit meat quality","authors":"Anne-Sophie Larivière-Lajoie, D. Cinq-Mars, Frédéric Guay, Simon Binggeli, Antoni Dalmau, Linda Saucier","doi":"10.4995/wrs.2021.14368","DOIUrl":"https://doi.org/10.4995/wrs.2021.14368","url":null,"abstract":"This study aimed to characterise the quality of meat from commercially-raised rabbits. Animals came from five different producers and were laughtered in three different plants under provincial or federal inspection jurisdiction. Animal behaviour evaluated by scan sampling prior to feed withdrawal (FW) and transport, as well as blood lactate concentration at exsanguination, did not raise concerns with respect to stress. Stomach pH was higher (P=0.047) when the FW time was short (≤13.5 h), at a mean value of 2.23. All pH values measured 1 h post-mortem from the Biceps femoris (BF) and almost all (97.6%) from the Longissimus lumborum (LL) were higher than 6. Values for ultimate pH measured 24 h postmortem(pHu) ranged from 5.80 to 6.83 and from 5.70 to 6.70 for BF and LL muscles, respectively. The maximum meat drip loss recorded was 2.6%, while cooking loss reached 30%. Meat lightness (L*) and colour intensity (C*) for the long FW times (≥23 h) were no different from those with short and intermediate (15.5 to 17.3 h) FW times. However, these colour parameters were higher for the short FW time class compared to the intermediate FW time class (P<0.02). A hierarchical cluster analysis based on pHu, cooking loss and lightness (L*) from 200 rabbit loins was performed. Of the four clusters created, clusters 1 and 2 had the best and second-best meat quality, respectively. Clusters 3 and 4 had the lowest meat quality and presented DFD-like (dark, firm and dry) characteristics. Meat did not exhibit PSE-like (pale, soft, exudative) characteristics, even for the slaughter lot with the minimum mean pHu. Of the eight slaughter lots evaluated, more than 50% of the meat from three of them fell into clusters 3 and 4; all three were in the intermediate FW time class. Overall, the quality of rabbit meat analysed was acceptable for commercial use, but rather variable. This suggests that there are factors within the value chain that are not yet fully controlled and require further investigation.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49291018","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}
A. Huneau-Salaün, S. Boucher, J. Fontaine, B. L. Normand, S. Lopez, Thimothée Maurice, Laurence Nouvel, Arthur Bruchec, J. Coton, G. Martin, G. Gall-Reculé, S. Bouquin
Rabbit haemorrhagic disease (RHD) is a critical health threat to the rabbit industry in Europe. In 2018, the French rabbit industry adopted a voluntary control plan against this disease. In this context, two epidemiological studies were conducted on RHD outbreaks that occurred between 2013 and 2018 in France. The objectives were to describe the spread of RHD due to the new genotype RHDV GI.2 (rabbit haemorrhagic disease virus GI.2) and to identify rearing factors influencing the occurrence of the disease in order to guide the prevention measures recommended in the control plan. An analysis of cases on 295 farms between 2013 and 2017 showed that 32% of farms were affected at least once; the incidence of the disease increased in 2016-2017 compared to 2013-2015. Farms already affected in 2013-2015 had a higher risk of being infected in 2016-2017 than those that remained unaffected until 2015 (Relative Risk and 95% Confident Interval 1.7 [1.1-2.7]). A case-control study carried out between 2016 and 2018 on 37 outbreaks and 32 control farms revealed variability in biosecurity and decontamination practices between farms. The risk of being infected tends to be linked to these practices, but certain structural factors (e.g. the manure disposal system, transfer of rabbits at weaning) could also influence the risk of virus introduction into farms. In the context of a limited vaccination coverage of the farms (only females are vaccinated), these hypotheses will be studied further, using information from the RHD outbreak monitoring system implemented at the same time as the control plan in 2018.
{"title":"Retrospective studies on rabbit haemorrhagic disease outbreaks caused by RHDV GI.2 virus on farms in France from 2013 to 2018","authors":"A. Huneau-Salaün, S. Boucher, J. Fontaine, B. L. Normand, S. Lopez, Thimothée Maurice, Laurence Nouvel, Arthur Bruchec, J. Coton, G. Martin, G. Gall-Reculé, S. Bouquin","doi":"10.4995/wrs.2021.12800","DOIUrl":"https://doi.org/10.4995/wrs.2021.12800","url":null,"abstract":"Rabbit haemorrhagic disease (RHD) is a critical health threat to the rabbit industry in Europe. In 2018, the French rabbit industry adopted a voluntary control plan against this disease. In this context, two epidemiological studies were conducted on RHD outbreaks that occurred between 2013 and 2018 in France. The objectives were to describe the spread of RHD due to the new genotype RHDV GI.2 (rabbit haemorrhagic disease virus GI.2) and to identify rearing factors influencing the occurrence of the disease in order to guide the prevention measures recommended in the control plan. An analysis of cases on 295 farms between 2013 and 2017 showed that 32% of farms were affected at least once; the incidence of the disease increased in 2016-2017 compared to 2013-2015. Farms already affected in 2013-2015 had a higher risk of being infected in 2016-2017 than those that remained unaffected until 2015 (Relative Risk and 95% Confident Interval 1.7 [1.1-2.7]). A case-control study carried out between 2016 and 2018 on 37 outbreaks and 32 control farms revealed variability in biosecurity and decontamination practices between farms. The risk of being infected tends to be linked to these practices, but certain structural factors (e.g. the manure disposal system, transfer of rabbits at weaning) could also influence the risk of virus introduction into farms. In the context of a limited vaccination coverage of the farms (only females are vaccinated), these hypotheses will be studied further, using information from the RHD outbreak monitoring system implemented at the same time as the control plan in 2018.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44241053","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}
K. G. Silva, T. D. Borges, L. B. Costa, C. Sotomaior
Rabbit production has great growth potential in a country where animal production is very important. However, there is little data about this industry in Southern and Southeast Brazil. The aim of this study was to describe Brazilian rabbit farms that provide meat, pets and animals for learning or research. Three pet farms, four meat farms and five research rabbit farms were visited, and the production and farm characteristics data were collected between June 2018 and March 2019. A total of 1170 rabbits and 617 cages were evaluated. Most farms had 21 to 60 (58.3%) does. Considering all farms, the farmers reported an average rate of conception of 71.8%, prolificacy rate of 6.7 kits per parturition, average interval between parturitions of 65 d and 6.3 parturitions/doe yr. The mean mortality rate for breeding rabbits was 10.4%, compared to 1.7% for growing rabbits (rabbits post-weaning until slaughter or sale). The average area of a cage was 0.43±0.1 m², with an average stocking density for growing rabbits of 3 rabbits/m². The most common cage system used by farmers was a flat-deck (66.7% of farms) system with a wire cage (91.7%). Metal (41.7%) and clay (33.3%) feeders were the most common types of feeders, and automatic nipple drinkers were present in 75% of the farms. Dirt accumulation was observed in 11.2% of the cages and 5.7% of the drinkers, but not in feeders. A total of 4.1% of the cages were considered unsafe, and 0.8% had problems with the drinkers. The farms studied ranged from small to medium in size, used an extensive reproductive rhythm and followed basic production techniques. Animal health and management aspects need to be reviewed by the farmer if the rabbit production conditions are to improve.
{"title":"Characteristics of meat, pet, and research rabbit farms in Brazil: An overview based on twelve farms","authors":"K. G. Silva, T. D. Borges, L. B. Costa, C. Sotomaior","doi":"10.4995/wrs.2021.14125","DOIUrl":"https://doi.org/10.4995/wrs.2021.14125","url":null,"abstract":"Rabbit production has great growth potential in a country where animal production is very important. However, there is little data about this industry in Southern and Southeast Brazil. The aim of this study was to describe Brazilian rabbit farms that provide meat, pets and animals for learning or research. Three pet farms, four meat farms and five research rabbit farms were visited, and the production and farm characteristics data were collected between June 2018 and March 2019. A total of 1170 rabbits and 617 cages were evaluated. Most farms had 21 to 60 (58.3%) does. Considering all farms, the farmers reported an average rate of conception of 71.8%, prolificacy rate of 6.7 kits per parturition, average interval between parturitions of 65 d and 6.3 parturitions/doe yr. The mean mortality rate for breeding rabbits was 10.4%, compared to 1.7% for growing rabbits (rabbits post-weaning until slaughter or sale). The average area of a cage was 0.43±0.1 m², with an average stocking density for growing rabbits of 3 rabbits/m². The most common cage system used by farmers was a flat-deck (66.7% of farms) system with a wire cage (91.7%). Metal (41.7%) and clay (33.3%) feeders were the most common types of feeders, and automatic nipple drinkers were present in 75% of the farms. Dirt accumulation was observed in 11.2% of the cages and 5.7% of the drinkers, but not in feeders. A total of 4.1% of the cages were considered unsafe, and 0.8% had problems with the drinkers. The farms studied ranged from small to medium in size, used an extensive reproductive rhythm and followed basic production techniques. Animal health and management aspects need to be reviewed by the farmer if the rabbit production conditions are to improve.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44895248","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}
K. G. Silva, Mariah Gomes Stange, Martina Pergorara, C. Sotomaior, S. Weber, T. D. Borges, L. B. Costa
Environmental enrichment improves rabbit welfare in rabbitries. Various toys for cats and dogs are commercially available, which are made of materials that could be safely used for rabbits as well. The objectives of this study were to evaluate whether cardboard and rubber materials could be used for environmental enrichment for rabbits. The study involved 42 adult New Zealand white rabbits (20 females and 22 males), randomly assigned to seven treatment groups: “C”, without object (control); “RB”, a solid rubber ball; “FT”, a fillable teether filled with hay; “CH”, a cardboard hole; “CS”, a piece of a cat scratcher; “CSC”, a piece of a cat scratcher with catnip; “CF”, an articulated cardboard fish. The behaviour of the rabbits and the percentage of destruction of the objects were recorded for 28 d. The normal behaviours of locomotion, rearing, stretching, stereotypies and sitting were not influenced by the treatments. Lying down was observed more frequently than the full stretched out position for resting. The FT-treatment group presented most behaviours of interaction (biting and sniffing) (P<0.05) as compared to RB, CSC, and CF-treatment groups. All the objects showed some level of destruction; the mean rates of destruction for CH, CS, CSC and CF were up to 40%, whereas those for FT and RB were under 30%. Taken together, the results suggest that cardboard and rubber materials can be used as means of environmental enrichment for rabbits.
{"title":"Cardboard and rubber objects as means of environmental enrichment for rabbits","authors":"K. G. Silva, Mariah Gomes Stange, Martina Pergorara, C. Sotomaior, S. Weber, T. D. Borges, L. B. Costa","doi":"10.4995/wrs.2021.14193","DOIUrl":"https://doi.org/10.4995/wrs.2021.14193","url":null,"abstract":"Environmental enrichment improves rabbit welfare in rabbitries. Various toys for cats and dogs are commercially available, which are made of materials that could be safely used for rabbits as well. The objectives of this study were to evaluate whether cardboard and rubber materials could be used for environmental enrichment for rabbits. The study involved 42 adult New Zealand white rabbits (20 females and 22 males), randomly assigned to seven treatment groups: “C”, without object (control); “RB”, a solid rubber ball; “FT”, a fillable teether filled with hay; “CH”, a cardboard hole; “CS”, a piece of a cat scratcher; “CSC”, a piece of a cat scratcher with catnip; “CF”, an articulated cardboard fish. The behaviour of the rabbits and the percentage of destruction of the objects were recorded for 28 d. The normal behaviours of locomotion, rearing, stretching, stereotypies and sitting were not influenced by the treatments. Lying down was observed more frequently than the full stretched out position for resting. The FT-treatment group presented most behaviours of interaction (biting and sniffing) (P<0.05) as compared to RB, CSC, and CF-treatment groups. All the objects showed some level of destruction; the mean rates of destruction for CH, CS, CSC and CF were up to 40%, whereas those for FT and RB were under 30%. Taken together, the results suggest that cardboard and rubber materials can be used as means of environmental enrichment for rabbits.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46384521","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}
Liu G.Y, Jiang W.X, Sun, H.T, Gao S.X, Yang L.P, Liu, Bai L.Y
This study aimed to evaluate the effects of dietary supplementation with taurine on production performance, serum biochemistry, immunoglobulin, antioxidant and hormones of Angora rabbits. A total of 160 8-month-old Angora rabbits with similar body weight were randomly assigned to one of four dietary groups, with 40 animals per group. The dietary groups consisted of the following different taurine supplementation levels: 0 (control), 0.1, 0.2, and 0.3% (air-dry basis). The 73-d feeding trial (from July 31 to October 11, 2016 in China) included a 7-d adjustment period and a 66-d experimental period. The results showed that taurine dietary supplementation had effects on feed consumption, hair follicle density and wool yield of the Angora rabbits ( P <0.05), and adding 0.2% taurine could improve the wool yield. Compared with the control group, serum total cholesterol and low-density lipoprotein levels in supplemented groups were decreased ( P <0.05). Dietary supplementation with taurine could improve the activity of superoxide dismutase, enhance total antioxidant capacity and reduce the content of malondialdehyde in serum ( P <0.05). Besides, the serum level of thyroid (T4) hormone and insulin-like growth factor-1 in experimental groups was higher than that in the control group ( P <0.05). In conclusion, taurine dietary supplementation could reduce the lipid metabolism, enhance the antioxidant capacity and hormone level of Angora rabbits, and adding 0.2% taurine could achieve the effect of increasing wool production.
{"title":"Effects of dietary supplementation with taurine on production performance of Angora rabbits","authors":"Liu G.Y, Jiang W.X, Sun, H.T, Gao S.X, Yang L.P, Liu, Bai L.Y","doi":"10.4995/WRS.2021.13133","DOIUrl":"https://doi.org/10.4995/WRS.2021.13133","url":null,"abstract":"This study aimed to evaluate the effects of dietary supplementation with taurine on production performance, serum biochemistry, immunoglobulin, antioxidant and hormones of Angora rabbits. A total of 160 8-month-old Angora rabbits with similar body weight were randomly assigned to one of four dietary groups, with 40 animals per group. The dietary groups consisted of the following different taurine supplementation levels: 0 (control), 0.1, 0.2, and 0.3% (air-dry basis). The 73-d feeding trial (from July 31 to October 11, 2016 in China) included a 7-d adjustment period and a 66-d experimental period. The results showed that taurine dietary supplementation had effects on feed consumption, hair follicle density and wool yield of the Angora rabbits ( P <0.05), and adding 0.2% taurine could improve the wool yield. Compared with the control group, serum total cholesterol and low-density lipoprotein levels in supplemented groups were decreased ( P <0.05). Dietary supplementation with taurine could improve the activity of superoxide dismutase, enhance total antioxidant capacity and reduce the content of malondialdehyde in serum ( P <0.05). Besides, the serum level of thyroid (T4) hormone and insulin-like growth factor-1 in experimental groups was higher than that in the control group ( P <0.05). In conclusion, taurine dietary supplementation could reduce the lipid metabolism, enhance the antioxidant capacity and hormone level of Angora rabbits, and adding 0.2% taurine could achieve the effect of increasing wool production.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":"29 1","pages":"11-18"},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46829585","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 order to establish a lighting regime suitable for rabbit farms in East China, the effects of lighting schedule, intensity and colour on the reproductive performance of rabbit does were evaluated by three experiments, respectively. In experiment 1, does were exposed to different lighting schedules: 16L:8D-continuous, 16L:8D-18d (6 d before artificial insemination (AI) to 12 d post-AI), 16L:8D-6d (6 d before AI to the day of AI) and 12L:12D-continuous. In experiment 2, does were exposed to different light intensities: 40 lx, 60 lx, 80 lx and 120 lx. In experiment 3, does were exposed to different light colours: white, yellow, blue and red. For all experiments, conception rate, kindling rate and pre-weaning mortality were calculated; litter size at birth, litter weight at birth, litter size at weaning, litter weight at weaning and individual kit weight at weaning were recorded. Results showed that none of the reproductive parameters of does were affected by the application of 16L:8D-18d lighting schedule compared with the continuous 16L:8D group (P>0.05). Moreover, rabbits does exposed to 80 lx light performed as well as those under 120 lx light in conception rate, kindling rate, litter size (total and alive) at birth and litter weight at birth (P>0.05). Furthermore, the exposures of 60 lx and 80 lx light were beneficial for litter weight at weaning. In addition, red light had a positive effect, as it led to a larger litter size and litter weight at weaning and lower pre-weaning mortality than white light (P<0.05). In summary, a 16L:8D photoperiod with 80 lx red light from 6 d before AI to 12 d post-AI is recommended for use in breeding of rabbit does according to our results.
{"title":"Effect of lighting schedule, intensity, and colour on reproductive performance of rabbit does","authors":"Yingjie Wu, Ang Zhao, Yinghe Qin","doi":"10.4995/WRS.2021.14623","DOIUrl":"https://doi.org/10.4995/WRS.2021.14623","url":null,"abstract":"In order to establish a lighting regime suitable for rabbit farms in East China, the effects of lighting schedule, intensity and colour on the reproductive performance of rabbit does were evaluated by three experiments, respectively. In experiment 1, does were exposed to different lighting schedules: 16L:8D-continuous, 16L:8D-18d (6 d before artificial insemination (AI) to 12 d post-AI), 16L:8D-6d (6 d before AI to the day of AI) and 12L:12D-continuous. In experiment 2, does were exposed to different light intensities: 40 lx, 60 lx, 80 lx and 120 lx. In experiment 3, does were exposed to different light colours: white, yellow, blue and red. For all experiments, conception rate, kindling rate and pre-weaning mortality were calculated; litter size at birth, litter weight at birth, litter size at weaning, litter weight at weaning and individual kit weight at weaning were recorded. Results showed that none of the reproductive parameters of does were affected by the application of 16L:8D-18d lighting schedule compared with the continuous 16L:8D group (P>0.05). Moreover, rabbits does exposed to 80 lx light performed as well as those under 120 lx light in conception rate, kindling rate, litter size (total and alive) at birth and litter weight at birth (P>0.05). Furthermore, the exposures of 60 lx and 80 lx light were beneficial for litter weight at weaning. In addition, red light had a positive effect, as it led to a larger litter size and litter weight at weaning and lower pre-weaning mortality than white light (P<0.05). In summary, a 16L:8D photoperiod with 80 lx red light from 6 d before AI to 12 d post-AI is recommended for use in breeding of rabbit does according to our results.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":"29 1","pages":"59"},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47065218","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. Martignon, C. Burel, D. Licois, E. Répérant, G. Postollec, C. Valat, T. Gidenne
The impact of a challenge with moderately pathogenic Escherichia coli O128:C6 on the digestive physiology and gut bacterial community of growing rabbits under two feeding programmes was analysed. Upon weaning (28 d old), 180 rabbits were allocated to four groups (9 cages of 5 rabbits per group) for two weeks: group C100 was non-inoculated and fed ad libitum; C70 was non-inoculated and feed intake was limited to 70% of C100; I100 and I70 were inoculated and fed ad libitum or restricted to 70%, respectively. At the age of 31 d (D0), rabbits were orally inoculated with E. coli (2.2×108 colony forming units/rabbit). The effects of inoculation spiked on D4, with a 28% lower growth rate for I100 than for C100. Limited feed intake reinforced the inoculation’s effects on growth: I70 had a 66% lower growth rate than C70. The morbidity rate peaked at 42% between D4 and D7 for inoculated groups, without significant effect of the feed intake level. E. coli concentration peaked on D5/D6 in the caecum of the I100 and I70 groups. Inoculation reduced by 30% (P<0.05) the villus height/crypt depth and villus/crypt area ratios in the ileum, with no significant effect of the intake level. Inoculation was associated with a tenfold increase in serum haptoglobin (P<0.001) for both ad libitum and restricted rabbits. On D5, the inoculation modified the structure of the ileal bacterial community (P<0.05), but not that of the caecum. The feed intake level did not affect either the structure or diversity of the bacterial community, both in the ileum and caecum.
{"title":"Challenging the growing rabbit with a moderately pathogenic E. coli under ad libitum or limited feed intake conditions: impact on digestive physiology, bacterial communities, and on post-weaning growth","authors":"M. Martignon, C. Burel, D. Licois, E. Répérant, G. Postollec, C. Valat, T. Gidenne","doi":"10.4995/WRS.2021.14089","DOIUrl":"https://doi.org/10.4995/WRS.2021.14089","url":null,"abstract":"The impact of a challenge with moderately pathogenic Escherichia coli O128:C6 on the digestive physiology and gut bacterial community of growing rabbits under two feeding programmes was analysed. Upon weaning (28 d old), 180 rabbits were allocated to four groups (9 cages of 5 rabbits per group) for two weeks: group C100 was non-inoculated and fed ad libitum; C70 was non-inoculated and feed intake was limited to 70% of C100; I100 and I70 were inoculated and fed ad libitum or restricted to 70%, respectively. At the age of 31 d (D0), rabbits were orally inoculated with E. coli (2.2×108 colony forming units/rabbit). The effects of inoculation spiked on D4, with a 28% lower growth rate for I100 than for C100. Limited feed intake reinforced the inoculation’s effects on growth: I70 had a 66% lower growth rate than C70. The morbidity rate peaked at 42% between D4 and D7 for inoculated groups, without significant effect of the feed intake level. E. coli concentration peaked on D5/D6 in the caecum of the I100 and I70 groups. Inoculation reduced by 30% (P<0.05) the villus height/crypt depth and villus/crypt area ratios in the ileum, with no significant effect of the intake level. Inoculation was associated with a tenfold increase in serum haptoglobin (P<0.001) for both ad libitum and restricted rabbits. On D5, the inoculation modified the structure of the ileal bacterial community (P<0.05), but not that of the caecum. The feed intake level did not affect either the structure or diversity of the bacterial community, both in the ileum and caecum.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":"29 1","pages":"1"},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49303508","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}
Male rabbit sexual behaviour consists of a single mount followed immediately by ejaculation. In young bucks this pattern changes gradually as they reach sexual satiety in a day and sexual exhaustion after several daily tests. Little is known about the characteristics of sexual behaviour in old rabbits (aged 48-54 mo) within a day and across daily tests leading to sexual exhaustion. By using sexually receptive (young) females, changed within a session to maximise copulation, we found that: a) the inter-ejaculatory interval increased between the first and last days of testing; b) test duration was 3.1 h on day 1 and 0.5 h on day 15; c) the “miss rate” (i.e., mounts not accompanied by ejaculation) significantly increased from the first to the last day of testing, regardless of when this occurred in each individual buck; d) the total number of ejaculations displayed in a session significantly decreased between the first and the last day of testing in all males; e) scent-marking (“chinning”) frequency significantly decreased after copulation to satiety, relative to that quantified at baseline, and was restored the following day. Compared with young bucks our results indicate quantitative, rather than qualitative, differences in sexual behaviour associated with age in rabbits. Specifically, on day 1 old bucks spent a shorter time engaged in copulation and displayed a lower number of ejaculations before reaching satiety than young males. In contrast, the interval between ejaculatory events and the “miss rate” increased across test days in both old and young rabbits. These results merit investigating the neuroendocrine mechanisms underlying the display of such an active sexual behaviour by old rabbit bucks.
{"title":"Study of copulatory behaviour in old male rabbits","authors":"P. Jiménez, E. Cuamatzi, G. González-Mariscal","doi":"10.4995/WRS.2021.14216","DOIUrl":"https://doi.org/10.4995/WRS.2021.14216","url":null,"abstract":"Male rabbit sexual behaviour consists of a single mount followed immediately by ejaculation. In young bucks this pattern changes gradually as they reach sexual satiety in a day and sexual exhaustion after several daily tests. Little is known about the characteristics of sexual behaviour in old rabbits (aged 48-54 mo) within a day and across daily tests leading to sexual exhaustion. By using sexually receptive (young) females, changed within a session to maximise copulation, we found that: a) the inter-ejaculatory interval increased between the first and last days of testing; b) test duration was 3.1 h on day 1 and 0.5 h on day 15; c) the “miss rate” (i.e., mounts not accompanied by ejaculation) significantly increased from the first to the last day of testing, regardless of when this occurred in each individual buck; d) the total number of ejaculations displayed in a session significantly decreased between the first and the last day of testing in all males; e) scent-marking (“chinning”) frequency significantly decreased after copulation to satiety, relative to that quantified at baseline, and was restored the following day. Compared with young bucks our results indicate quantitative, rather than qualitative, differences in sexual behaviour associated with age in rabbits. Specifically, on day 1 old bucks spent a shorter time engaged in copulation and displayed a lower number of ejaculations before reaching satiety than young males. In contrast, the interval between ejaculatory events and the “miss rate” increased across test days in both old and young rabbits. These results merit investigating the neuroendocrine mechanisms underlying the display of such an active sexual behaviour by old rabbit bucks.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":"29 1","pages":"41"},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47250363","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. Gencheva, T. Koynarski, Vanya Dafova, S. Tanchev
Five rabbit populations of New Zealand White (NZW), Californian (CAL), crossbred NZW×GW and two generations of the synthetic population – SPF1 and SPF2 reared in Bulgaria were included in the present study with the aim of detecting the genetic variability of the growth hormone encoding gene (GH) via polymerase chain reaction with the restriction fragment length polymorphism analysis and direct sequencing. The targeted region of the rabbit GH gene was amplified and a fragment of a total of 231 bp was obtained in all studied populations. Allele identification was determined after enzymatic digestion, where two fragments of 62 and 169 bp correspond to allele C and an undigested fragment of 231 bp corresponds to allele T. Two additional bands of 107 and 124 bp evidenced A/G genetic polymorphism in the rabbit GH gene. Thirtyeight percent of the studied rabbits were carriers of the double mutation (C/T+A/G) in the same locus as the studied GH gene. The sequence analysis revealed two nucleotide substitutions – g.111C>T and g.156A>G in the non-coding region between the regulatory TATA box and 5’ UTR region, and a novel g.255G>A genetic variant in intron 1 of GH gene. The A>G transition was most frequent (40.57%), compared to the other ones, G>A (28.57%) and C>T (10.80%), respectively. The most frequent genotype in the NZW population was homozygous TT (0.93), with a prevalence of the T allele (0.97) over allele C (0.03) for g.111C>T SNP site. The distribution of the allele and genotype frequencies at the sites g.156A>G and g.255G>A in this rabbit group was identical, with the highest value of 0.93 for alleles A and G, respectively. The rabbit populations CAL and NZW×GW showed equal frequencies of the prevalent T allele (0.83) and for homozygous TT genotype (0.67) according to g.111C>T SNP. The highest values were obtained for the allele А (0.83) and for homozygous AA genotype (0.67) at c.33A>G SNP in these rabbit groups. The highest values (0.67, 0.60 and 0.80) for the heterozygous genotypes at g.111C>T, g.156A>G and g.255G>A SNPs, respectively, were detected among the SPF2 rabbit population, compared to the both homozygous genotypes. The results obtained in the present research indicates a significant degree of genetic variability of the studied polymorphic GH locus in the SPF2 rabbit group.
{"title":"Identification of nucleotide variation of growth hormone gene in rabbit populations reared in Bulgaria","authors":"D. Gencheva, T. Koynarski, Vanya Dafova, S. Tanchev","doi":"10.4995/WRS.2021.12693","DOIUrl":"https://doi.org/10.4995/WRS.2021.12693","url":null,"abstract":"Five rabbit populations of New Zealand White (NZW), Californian (CAL), crossbred NZW×GW and two generations of the synthetic population – SPF1 and SPF2 reared in Bulgaria were included in the present study with the aim of detecting the genetic variability of the growth hormone encoding gene (GH) via polymerase chain reaction with the restriction fragment length polymorphism analysis and direct sequencing. The targeted region of the rabbit GH gene was amplified and a fragment of a total of 231 bp was obtained in all studied populations. Allele identification was determined after enzymatic digestion, where two fragments of 62 and 169 bp correspond to allele C and an undigested fragment of 231 bp corresponds to allele T. Two additional bands of 107 and 124 bp evidenced A/G genetic polymorphism in the rabbit GH gene. Thirtyeight percent of the studied rabbits were carriers of the double mutation (C/T+A/G) in the same locus as the studied GH gene. The sequence analysis revealed two nucleotide substitutions – g.111C>T and g.156A>G in the non-coding region between the regulatory TATA box and 5’ UTR region, and a novel g.255G>A genetic variant in intron 1 of GH gene. The A>G transition was most frequent (40.57%), compared to the other ones, G>A (28.57%) and C>T (10.80%), respectively. The most frequent genotype in the NZW population was homozygous TT (0.93), with a prevalence of the T allele (0.97) over allele C (0.03) for g.111C>T SNP site. The distribution of the allele and genotype frequencies at the sites g.156A>G and g.255G>A in this rabbit group was identical, with the highest value of 0.93 for alleles A and G, respectively. The rabbit populations CAL and NZW×GW showed equal frequencies of the prevalent T allele (0.83) and for homozygous TT genotype (0.67) according to g.111C>T SNP. The highest values were obtained for the allele А (0.83) and for homozygous AA genotype (0.67) at c.33A>G SNP in these rabbit groups. The highest values (0.67, 0.60 and 0.80) for the heterozygous genotypes at g.111C>T, g.156A>G and g.255G>A SNPs, respectively, were detected among the SPF2 rabbit population, compared to the both homozygous genotypes. The results obtained in the present research indicates a significant degree of genetic variability of the studied polymorphic GH locus in the SPF2 rabbit group.","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":"29 1","pages":"19"},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48893242","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. Khalil, Abdelfatah R. Zaghloul, M. Iraqi, A. E. El Nagar, S. Ramadan
Although growth hormone (GH) gene mutations are described in several species, the studies concerning their variabilities and associations with economic traits in rabbits are scarce, particularly associations with semen traits. A total of 149 rabbit bucks from five populations (V-line=36, Moshtohor line=28, APRI line=42, cross ½A½M=23, and Gabali=20) were used in the present study to identify polymorphism of c.-78 C>T single nucleotide polymorphism (SNP) of GH gene among these populations and to investigate the association of GH gene polymorphism with body weight (BW), daily weight gain (DG) and semen traits. DNA was extracted from blood samples for genotyping of c.-78 C>T SNP of GH gene based on polymerase chain reaction with the restriction fragment length polymorphism (PCR-RFLP) technique. The genetic diversity of SNP C>T of GH gene was assessed in terms of genotypic and allelic frequencies, effective number of alleles (Ne), observed (Ho) and expected (He) heterozygosity, Hardy-Weinberg equilibrium (HWE), reduction in heterozygosity due to inbreeding (FIS) and polymorphism information content (PIC). Three genotypes of TT, CC and TC of PCR product of 231 bp of GH gene were detected and all the populations were in HWE in terms of GH gene. The highest Ne was obtained for the Moshtohor line (1.978), while the lowest allelic numbers were obtained for V-line (1.715) and Gabali breed (1.800). The highest genotype frequency of GH gene was 0.48 in TT genotype of V-line, 0.21 in CC genotype of Moshtohor line, 0.67 and 0.56 in TC genotype of ½A½M and Gabali rabbits (P<0.05). The highest frequency for C allele was recorded by Moshtohor line (0.45) and the lowest frequency by Gabali (0.32). The genetic diversity scores for GH gene were intermediate (Ho=0.551, He=0.471, PIC=0.358). The values of Ho ranged from 0.444 in V-line to 0.667 in ½A½M cross, while the values of He were 0.425 in V-line and 0.508 in Moshtohor line. The values of PIC were moderate and ranged from 0.332 in V-line to 0.375 in M-line. The highest FIS was observed in Moshtohor line (0.042) and the lowest value was observed in ½A½M cross (–0.413). The CT genotype of GH gene showed the highest and significant values for body weights at 4, 8, 10 and 12 wk (542, 1131, 1465 and 1861 g) and daily gains at intervals of 4-6 and 8-10 wk (23.1 and 26.5 g). Additionally, the CT genotype recorded the highest and significant values for volume of ejaculate (1.1 mL), sperm motility (57.6%), live sperm (85.6%), normal sperm (93.1%) and sperm concentration in semen (611×106/mL), along with the lowest and significant values for dead sperms (14.4%) and abnormal sperms (6.9%).
{"title":"Association of GH gene polymorphism with growth and semen traits in rabbits","authors":"M. Khalil, Abdelfatah R. Zaghloul, M. Iraqi, A. E. El Nagar, S. Ramadan","doi":"10.4995/WRS.2021.13001","DOIUrl":"https://doi.org/10.4995/WRS.2021.13001","url":null,"abstract":"Although growth hormone (GH) gene mutations are described in several species, the studies concerning their variabilities and associations with economic traits in rabbits are scarce, particularly associations with semen traits. A total of 149 rabbit bucks from five populations (V-line=36, Moshtohor line=28, APRI line=42, cross ½A½M=23, and Gabali=20) were used in the present study to identify polymorphism of c.-78 C>T single nucleotide polymorphism (SNP) of GH gene among these populations and to investigate the association of GH gene polymorphism with body weight (BW), daily weight gain (DG) and semen traits. DNA was extracted from blood samples for genotyping of c.-78 C>T SNP of GH gene based on polymerase chain reaction with the restriction fragment length polymorphism (PCR-RFLP) technique. The genetic diversity of SNP C>T of GH gene was assessed in terms of genotypic and allelic frequencies, effective number of alleles (Ne), observed (Ho) and expected (He) heterozygosity, Hardy-Weinberg equilibrium (HWE), reduction in heterozygosity due to inbreeding (FIS) and polymorphism information content (PIC). Three genotypes of TT, CC and TC of PCR product of 231 bp of GH gene were detected and all the populations were in HWE in terms of GH gene. The highest Ne was obtained for the Moshtohor line (1.978), while the lowest allelic numbers were obtained for V-line (1.715) and Gabali breed (1.800). The highest genotype frequency of GH gene was 0.48 in TT genotype of V-line, 0.21 in CC genotype of Moshtohor line, 0.67 and 0.56 in TC genotype of ½A½M and Gabali rabbits (P<0.05). The highest frequency for C allele was recorded by Moshtohor line (0.45) and the lowest frequency by Gabali (0.32). The genetic diversity scores for GH gene were intermediate (Ho=0.551, He=0.471, PIC=0.358). The values of Ho ranged from 0.444 in V-line to 0.667 in ½A½M cross, while the values of He were 0.425 in V-line and 0.508 in Moshtohor line. The values of PIC were moderate and ranged from 0.332 in V-line to 0.375 in M-line. The highest FIS was observed in Moshtohor line (0.042) and the lowest value was observed in ½A½M cross (–0.413). The CT genotype of GH gene showed the highest and significant values for body weights at 4, 8, 10 and 12 wk (542, 1131, 1465 and 1861 g) and daily gains at intervals of 4-6 and 8-10 wk (23.1 and 26.5 g). Additionally, the CT genotype recorded the highest and significant values for volume of ejaculate (1.1 mL), sperm motility (57.6%), live sperm (85.6%), normal sperm (93.1%) and sperm concentration in semen (611×106/mL), along with the lowest and significant values for dead sperms (14.4%) and abnormal sperms (6.9%).","PeriodicalId":23902,"journal":{"name":"World Rabbit Science","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2021-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43400179","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}
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