• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.981-986
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• 2010

Genetic parameters of growth traits were estimated in the German Angora rabbit reared in the sub-temperate region of India. Estimates of (co)variance components were obtained for body weights at weaning (42 days) and post-weaning at 84, 126 and 168 days. A total of 8,324 animal records were used for the analysis of these traits. The data were analyzed by restricted maximum likelihood (REML) fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate univariate model for each trait. Direct heritability estimates were observed to be moderate for the traits under study. Heritability estimates for weaning (42 d), 84, 126 and 168 d weights obtained from the best models were $0.25{\pm}0.05$, $0.17{\pm}0.05$, $0.21{\pm}0.06$ and $0.12{\pm}0.05$. Maternal effects had higher importance at weaning, and declined with the advancement of age. Significant maternal permanent environmental effect on weaning and post-weaning weights was a carryover effect of maternal influences during pre-weaning age. The estimated repeatabilities of doe effects on body weights were 0.37, 0.22, 0.18 and 0.28 at weaning, 84, 126 and 168 d body weight, respectively. Results indicated that modest rate of genetic progress is possible for body weight traits of Angora rabbit through selection. Similarly, these growth traits could be included in selection criteria along with wool traits for early selection of the animals.

• Journal of Animal Science and Technology
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• v.59 no.12
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• pp.25.1-25.7
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• 2017

Background: Rabbit breeding with high performance imported ones would be of benefit for genetic diversity and improvement of performance in domestic rabbit breeds. The rearing of more productive rabbit breeds could be pathway to improve the productivity and reduce the production cost. Maternal nutritional status exert a great influence on reproductive functions of does, which may expand from conception, through gestation and parturition and development of kits to puberty. Methods: Four breeds of rabbit were evaluated for their parturition, weaning and pubertal differences among the rabbit population in Ibadan, Nigeria. The breed consist of Fauve De Bourgogne (FDB), Chinchilla (CHA), British Spot (BS) and New Zealand White (NZW) rabbits. A total of 60 bucks and 360 does consisting of 15 bucks and 90 does per breed were mated in 6 mating cycles, three each of natural mating and artificial insemination. All does were synchronized for estrus with 20 IU pregnant mare serum gonadotropin 48 h prior to mating. The does after parturition were assessed for milk yield (g) and kit survival rate (%) till weaning, weight changes of kits from birth to puberty. At puberty, the pubertal age (days) and weight (g) of the offspring were assessed. Result: Results obtained reveals that British Spot doe had highest milk yield among the breeds which significantly increased growth of kit and weight at weaning in British Spot rabbits. Survival rates of Chinchilla kits were significantly (p < 0.05) higher than Fauve de Bourgogne, British Spot and New Zealand White kits. Puberty attainment of the rabbits indicates that British spot does and Fauve de Bourgogne bucks are early maturing. Conclusion: Chinchilla shows high kit survivability and British spot has highest milk yield among the four breeds of rabbit.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1335-1340
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• 2011

Different genetic parameters for weaning weight and wool traits were estimated using restricted maximum likelihood (REML) in Angora rabbits. Total wool yield of first (I), second (II) and third (III) clips were taken as a separate trait under study. The records from more than 2,700 animals were analysed through fitting six animal models with various combinations of direct and maternal effects. A log likelihood ratio test was used to select the most appropriate model for each trait. Direct heritability estimates for the wool traits were found to be moderate to high across different models. Heritability estimates obtained from the best model were 0.24, 0.22, 0.20 and 0.21 for weaning weight, clip I, II and III; respectively. Maternal effects especially due to permanent environment had higher importance at clip I and found to be declining in subsequent clips. The estimates of repeatability of doe effect on wool traits were 0.44, 0.26 and 0.18 for clip I, II and III; respectively. Weaning weight had moderately high genetic correlations with clip I (0.57) and II (0.45), but very low (0.11) with clip III. Results indicated that genetic improvement for wool yield in Angora rabbit is possible through direct selection. Further, weaning weight could be considered as desirable trait for earliest indirect selection for wool yield in view of its high genetic correlation with wool traits.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.10
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• pp.1421-1424
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• 2005

The aim of this study was to evaluate the effect of two diets different in crude fibre content and ingredients on performance and on caecal characteristics of rabbits around weaning. Thirty litters from thirty New Zealand White does were divided at Day 18 in two groups fed, respectively, a low fibre concentrate (LFC, consisting mainly of soybean meal, delactated whey, barley) from Day 18-28 followed by a creep feed (CF, consisting mainly in alfalfa meal, barley and wheat bran) from Day 29-32, and a CF from Day 18-32. After weaning (32 days) both groups were fed the CF ad libitum for two weeks. During the pre-weaning period, mortality, milk intake and solid feed intake (from Day 20) were recorded daily, while the live weight of kits was recorded twice, at 18 and 32 days. At day 28, one rabbit/litter was slaughtered in order to obtain data on caecal content characteristics. After weaning, the rabbits were located in collective cages, feeding ad libitum CF; feed intake, live weight and mortality were recorded weekly for two weeks. During the preweaning period, there were no differences between the groups in milk and solid feed intake and, by consequence, in live weight at weaning; instead, the mortality was higher (12.5 vs 4.5%) for the group (A) that changed diet at 28 days. Group A showed also a higher caecal pH (6.12 vs. 5.72), propionate to butyrate ratio (0.73 vs. 0.46), ammonia content (9.3 vs. 7.1 mmol/l), but a lower total volatile fatty acid content (66.8 vs. 82.1 mmol/l) than B Group, probably due to the dried milk whey in the concentrate. After weaning, there were no significant differences between the two groups. The authors concluded that the use of a low fibre concentrate for suckling rabbits is not recommended.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.432-442
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• 2022

The purpose of this study was to analyse the effects of light colour on rabbit reproductive performance and the expression of key follicular development genes. Rabbits (n = 1,068, 5 months old, 3.6-4.4 kg live body weight) were divided randomly into four groups, housed individually in wire mesh cages and exposed to red, green, blue, and white light-emitting diode (LED) light (control). The lighting schedule was 16 L : 8 D-15 d / 150 lx / 6:00 am-22:00 pm (3 d preartificial insemination to 12 d postartificial insemination). Red light and white light affected the conception rate and kindling rate and increased the total litter size at birth (p < 0.05). The effects of red light on litter size at weaning, litter weight at weaning, and individual weight at weaning increased compared with the green and blue groups. The effects of red light on live litter size at birth were increased compared with those in the blue group (p < 0.05). Compared to white light, green and blue light reduced the number of secondary follicles (p < 0.05). Compared to red light, green and blue light reduced the number of tertiary follicles (p < 0.05). Compared with white light, red LED light resulted in greater ovarian follicle stimulating hormone receptor and luteinizing hormone receptor mRNA expression (p < 0.05). Compared with green and blue LED light, red LED light resulted in greater B-cell lymphom-2 mRNA expression (p < 0.05). Compared with green LED light, red LED light inhibited FOXO1 mRNA expression in rabbit ovaries (p < 0.05). Red light can affect the reproductive performance of female rabbits and the expression of key genes for follicular development.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.1
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• pp.43-49
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• 2013

The aim of this study was to compare both the performance of litters derived from two sire genetic origins (SGO), Vienna Blue (VB) and Burgundy Fawn (BF), along successive seasons of birth (SB; winter, spring, summer and autumn), and doe reproductive performance in an organic production system. A total of fifty-eight does consisting of a mixture of crosses of several medium-large size breeds at different parity order (P, 1 = nulliparous; 2 = primiparous; ${\geq}3$ = multiparous) and twelve males (6 VB and 6 BF) were housed indoors at environmental conditions that followed seasonality. An extensive reproductive rhythm was used and kits were weaned at $46{\pm}6$ d of age. Doe reproductive performance and the data of 105 litters (55 from VB and 50 from BF SGO) were recorded throughout the SB. No statistically significant differences related to SGO effect were observed. As regards parity order, multiparous does showed higher live weights (LW) (p<0.05), total born (p<0.01), total born alive (p<0.05) per delivery, and litter weight of born alive (p<0.05), but lower milk output at 21st d than primiparous does (p<0.05). The extensive reproductive rhythm mainly increased litter performance at birth in multiparous does but was not sufficient to permit a complete recovery of body reserves lost during lactation. Autumn SB negatively affected doe LW variation between deliveries. The number of pups born and born alive per delivery (p<0.05) and litter size at 21 d of age and at weaning (p<0.01) were lower during hot SB. Due to the lower litter size of pups born in summer and autumn, their individual weight at 21st d of age and daily individual growth rate 0 to 21 d were higher than those of pups born in winter (p<0.001). Litter performance at 21st d of age and individual pup pre-weaning growth rate were poorer for those born in spring than in other seasons due to the harmful effects of increased environmental temperatures. SB affected most of the performance traits of does and young rabbits reared under the organic farming system. The rabbits seemed better suited to organic rearing conditions during winter than in other seasons. The worst results overall were obtained in the spring SB, whereas the hot SB negatively affected both doe energy balance and prolificacy. In conclusion, the pups of the 2 SGO showed good pre-weaning performance and seemed suited to the organic rabbit production system.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.198-205
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• 2017

Objective: This study aimed to investigate the effects of single or/and double strains of probiotic supplement on feed efficiency, growth performance, and microbial population in distal gastrointestinal tract (GIT) of weaning rabbits. Methods: Sixty-four weaning (28 days old) New Zealand White rabbits were randomly distributed into four groups with treatments including: basal diet without probiotic supplement (control) or supplemented as follows: $1{\times}10^6cfu/g$ B. subtilis (BS group), $1{\times}10^7cfu/g$ L. acidophilus (LA group), or $0.5{\times}10^6cfu/g$ B. subtilis plus $0.5{\times}10^7cfu/g$ L. acidophilus (BL group). During the research, the male and female rabbits were fed separately. Body weight of the rabbits was recorded at 28, 42, and 70 d of age. Results: There was an increase (p<0.05) in body weight gain for the LA group at 42 d. Rabbits fed BL responsed with a greater growth (p<0.05) and better feed conversion ratio (p<0.05) than those fed with no probiotic. Digestibility coefficients of dry matter, organic matter, crude protein, neutral detergent fiber, and gross energy were higher (p<0.05) in LA and BL groups than those in the control group. Male rabbits had higher (p<0.05) Bacilli spp. and Coliformis spp. in the ileum than female rabbits. Rabbits supplemented with BS had greater (p<0.05) numbers of bacilli in all intestinal segments than those receiving no probiotic, whereas intestinal Lactobacilli populations were greater (p<0.001) in the LA and BL diets compared to control. Average intestinal coliform populations were lowest (p<0.05) in the rabbits supplemented with LA as compared to those fed the control and BS. Conclusion: Supplementation of L. acidophilus alone or in combination with B. subtilis at a half of dose could enhance number of gut beneficial bacteria populations, nutrient digestibility, cecal fermentation, feed efficiency, and growth performance, but rabbits receiving only B. subtilis alone were not different from the controls without probiotic.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.5
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• pp.738-748
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• 2012

One of the main goals of small, medium and large farms is to improve the reproductive performance of rabbit does. Stocks of lower productivity can be improved by crossing with intensive breeds. A better nutritional status of both foetuses and suckling kits has a positive effect on their later productivity. Overfeeding young females before first mating can lead to conditions of fattiness. Using restricted feeding or higher fibre content in the feed and changing it for a higher level ad libitum feeding about one week prior to first mating leads to longer lifespan and higher productive level. Intensive reproductive rhythm creates a negative energy balance in does : they are unable to consume enough feed (energy) for the nutritional requirements of foetus and lactation, and therefore lose most of their fat reserves. Furthermore, primiparous does also expend energy because they are still growing. Under intensive conditions, the 42-d reproductive rhythm (re-mating 11 days after parturition) is recommended. Under extensive conditions, the 18 or 25-d mating interval with 35 to 42-d weaning could be suitable. On small farms, natural mating is favoured; on large farms AI is commonly employed. The main advantage of AI is the all-in, all-out system. Hormonal (PMSG) treatment is used with AI to increase receptivity on d 11. Frequent and high level PMSG use can lead to higher anti-PMSG antibody rates. Lower level (max. 20 IU) and less frequent PMSG injection or non-hormonal alternative methods (short dam-litter separation, changing nursing method or lighting programs) are recommended for this reason.

• Korean Journal of Veterinary Research
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• v.28 no.1
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• pp.89-97
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• 1988

Twenty-eight porcine rotavirus were isolated from piglets with diarrhoea in chonnam province. According to the age, 41 to 60 day old pigs showed the highest isolation frequency among the post weaning pigs. The characteristics of the field isolates were determined by electronmicroscopy(EM), immunofluorescent assay(FA), and electrophoretic migration patterns of the genome profiles. Some of the isolates showed remarkable haemagglutination activity against rabbit and dog erythrocytes, ranged from 4 to 2848, respectively. At least 3 serotypes of porcine rotavirus were recognized by serum neutralization test using serotype specific rotavirus hyperimmune sera.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.9
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• pp.1361-1366
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• 2008

One-hundred and twenty Ischia grey rabbits, traditionally raised in pits, were equally divided after weaning (32 days) into three groups: group C, housed in cages (4 rabbits/cage) and fed a commercial concentrate; group GF, housed as C group and fed grasses collected on the island and crushed faba beans supplemented with an appropriate mineral vitamin mix; group P, housed in pits (8 rabbits/pit) and fed as GF group. Feed intake was recorded daily and live weight monthly up to slaughter (92 days). At slaughter, 10 rabbits per group were used to measure carcass and meat traits. The carcasses were weighed and measured according to the standard procedures and meat samples from the Longissimus dorsi and left hind leg were analysed for water holding capacity and chemical composition, respectively. During the entire trial, group C consumed significantly (p<0.01) a higher quantity of feed than the other groups (126.1 vs. 63.4 and 66.5 g/d, resp. for groups C, GF and P) and at slaughter showed a significantly (p<0.01) higher body weight (2,529.7 vs. 1,324.4 and 1,375.4 g, resp. for groups C, GF and P). Significant differences (p<0.01) were found also for dressing out percentage (68.6 vs. 66.6 and 66.9%, resp. for groups C, GF and P) and for meat chemical composition, in particular lipid percentage (4.13 vs. 1.84 and 1.93%, resp., for groups C, GF and P, p<0.01) and moisture (73.7 vs. 76.4 and 76.3%, resp. for groups C, GF and P, p<0.01). The results suggest the opportunity to obtain heavier animals raised in the pits if their diets were integrated with commercial feed.