CC BY
02020, Scienceline Publication
Worlds Veterinary Journal
World Vet J, 10(3): 405-413, September 25, 2020
DOI: https://dx.doi.org/10.36380/scil.2020.wvj50
Assessment of Genetic Capability for Post-Weaning Growth Traits of Reciprocal Cross between Gabali and V-Line Rabbits Using an Animal Model
Tarik Rabie1 *, Amira Nowier2, Adel Abou-Zeid3 and Adel Khattab3
1 Animal Production Department, Faculty of Agriculture, Suez Canal University, Ismailia, 41522, Egypt.
2 Animal Production Research Institute, Agriculture Research Center, Ministry of Agriculture, Egypt.
3 Tanta University, Faculty of Agriculture, Animal Production Department, Egypt. "Corresponding author's Email: tarik.rabie@agr.suez.edu.eg; : 0000-0001-9678-2323
ABSTRACT
This study aimed to assess the conceivable impact of hereditary factors on the crossbreeding rabbit groups set up by proportional going between Sinai Gabali and V-Line. Reciprocal cross on the post-weaning performances was performed by estimating the genetic capability for their crosses. The study samples included two pure rabbit breeds (a male Saini Gabali (G) and a female V-Line (V)), and reciprocal crosses to compromise 10 groups. Records of 448 kits delivered by 45 does and 16 bucks were utilized to estimate Heritability (h2), genetic and phenotypic correlations, and breeding values of litter weight traits. First generation was created from the consequences of four parities (%G %V, and V sire breed was demonstrated first). Weaning was implemented on the 28th day of the kits' age. Post-weaning litter traits were measured Body weight (BW) at 4, 5, 6, 8, 10, and 12 weeks of their age; and average daily gain was measured during 4-8 weeks (ADG4-8, ADG4-12, ADG8_10, and ADG8-12). Data were examined by animal model, which was performed utilizing derivate free limited maximum likelihood. The results revealed that h2 was moderate for both breeds, and its reciprocal cross ranged from 0.2 to 0.25, and BW at weaning was 0.22 ± 0.07. Meanwhile, there was a positive genetic correlation between BW and ADG at different age ranges (ranged 0.02 to 0.77, 0.04 to 0.76, respectively). Assessments of environmental correlation between BW at different age ranges were negative, except of those between BW8 and BW12 which were positive, but not significant. Additionally, the progeny had higher predicting breeding values for BW at 4, 8,10, and 12 weeks for both breeds, but that was obtained from G*V exceeding those from their reciprocal cross. In conclusion, direct additive variance was considerably effective, and consequently body weight at weaning and post-weaning growth traits could be improved by utilizing bucks of Sinai Gabali with doesof V-line based on the performance of their progenies, and selection of sires and dams.
Keywords: Genetic correlation, Heritability, Post-weaning, Sinai gabali, V-line, Weaning weight INTRODUCTION
The expected global needs for the meat at 2050 are about 73% compared to present mass production. The developing countries will contribute for most of this expansion due to fast population growth and ascending of capital income (FAO, 2011; OECD, 2017). Obike and Ibe (2010) conveyed that rabbits are considered as a high-quality source of protein with cheap price, which can be used to improve the animal production of protein in low revenue populations (Makkar et al., 2014). Furthermore, the rabbits had many compensations above other animals for low cost meat production, for instance, high growth rate, high feed conversion, and their ability to utilize fibrous feeds, both of sexual maturity and short gestation length resulted in a short generation interval, also, the rabbits' meat was classified as a high-quality meat (Herbert, 2011). In addition, growth rate in rabbits, particularly their post-weaning was intensely affected by genotype and environmental condition including the availability of both quality and quantity of feed. Furthermore, the diversity of the rabbit breeds gave more opportunities to improve the meat production by divergent breeds crossing (Piles et al., 2004).
Heritability, which is an element of variance components, gave data about the hereditary idea of a characteristic and is required for genetic assessment and selection procedures (El-Raffa, 2005). Phenotypic variance assumed a vital part for post-weaning traits in rabbits was generally depicted to be overwhelmed by ecological impacts inferable from the does or potentially litter, which might owe the short interval from the weaning to marketing. Moreover, low heritability and direct proportions of genetic responses to select for post-weaning growth traits were conveyed (Lukefahr
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et al., 1996). The rabbits' genetic improvements were mainly conditional on the heritability of the defined traits, and its association with different other traits of economic importance were measured. A moderate to high heritability (0.7-0.9) for litter weight at 7-8 weeks old, while the repeatability generally indicating low estimates (0.003-0.008) were obtained by Okoro et al. (2012). In oppose with Iraqi, 2008 who found that estimating of heritability were 0.05 to 0.38 body weight (BW) at 4, 8, and 12 weeks old, while these estimations were 0.23 and 0.19 for daily gain from 4 to 8, and 8 to 12 weeks of age, correspondingly. Though, additive genetic variability was far from being considered negligible. To facilitate, and to make rapid improvements in rabbits' performance, it could be inaugurated from selection and use of divergent breeds in the crossbreeding (Chineke and Raheem, 2009). In addition, crossbreeding is efficient for improving the post-weaning growth potential (Piles et al., 2004). Besides, selection in maternal lines in rabbit was somewhat considering determination inside limited population which amassed in mating grouping impacts (Ragab et al., 2015), extending the hereditary variety amongst lines and, verifiably, changing the gene frequencies between population. Furthermore, to employ genetic resources effectively, the genetic and environmental causes of phenotypic alteration in economic attributes need to be differentiated (Gorbani and Salamatdoust, 2011). The intention of rabbits' breeding was to improve execution characteristics of rabbits' population through both mating and selection. Accordingly, the targets of the existing research were to assess conceivable impact of hereditary factors on crossbreeding rabbit groups set up by proportional going between Sinai Gabali and V-Line (as a unique lines) by reciprocal cross on post-weaning performances by estimate the genetic capability for their crosses.
MATERIALS AND METHODS
Ethical approval
The experiment was carried out according to the National Regulations on Animal Welfare and Institutional Animal Ethics Committee, Egypt.
Breeding plan
Two pure rabbit breeds were used in current study (Saini Gabali (G), and V-Line (V) as a standard exotic line). Does and bucks of the V were acclimatized descendants of the Spanish synthetic line. Crossbreeding system was applied in ten mating groups which contained 4 to 5 does per group. The first five groups consisted of V does which were mated with five G bucks (G$ X V$), and reciprocal crosses (V$ X G$) for the further five groups. Each buck was represented as a sire to all litters in each group to produce Fj (/ G / V and '/2 V/ G; sire breed was indicated first). Weaning was implemented at 28 days of kits' age.
Rabbitry, housing and management
Animals were raised in a semi closed rabbitry, depending on the natural ventilation. Does were housed individually in pens where there were settle boxes, feeders, and automatic drinkers. All rabbits were fed on a commercial lactating-pelleted-diet containing approximately 2600 Kcal/kg ration as digestible energy; 16.3% crude protein; 13.2% crude fiber and 2.5% fat. Both of feed and water were provided ad libitum. Does mated their same respective group assigned bucks 10 days post-kindling. Pregnancy was ascertained by palpation 10 days of succeeding mating. Females that neglected to conceive were come back to the same assigned buck to be re-reproduced. Inside 12 hours once encouraging, litters were checked and recorded. In this way, weaned a month kits were sexed and exchanged for additional study to standard descendants prepared pens.
Source of data
Post-weaning litter traits were body weight (BW4) at , 5, 6, 8, 10, and 12 weeks old, average daily gain between 4 to 8 weeks (ADG4-8), 4 to 12 weeks (ADG4-12), 8 to 10 weeks (ADG8-10), and 8 to 12 weeks (ADG8-12).
Statistical analysis
Linear model
Data were preliminary analyzed using general linear model (GLM) and VARCOMP procedures of Statistical Analysis System (SAS, 2001, version 8.1). In addition, single and multi-traits animal model analyses (AM), were performed using derivate free restricted maximum likelihood as recommended by Boldman et al. (1995). For the derivative- free model, convergence (co) variance components estimation was when the global maximum of the log likelihood function was found.
Estimation of heritability (h )
The following formula was used by the animal model software to estimate h2
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h2 =
2 2 n , 2 c a + c P + c e
Where,
a2 a : was additive genetic variance a2P e: was permanent environmental variance, and a2e: were random residual associated with each observation.
Estimation of correlations
The following formula was used as recommended by Franzese and Iuliano (2019).
cov(xy) y
Yw — '
jo2xij^o2yij Where,
cov(xy) = The additive genetic covariance, a1 xij = The additive genetic variance of the trait (or permanent environmental, environmental and phenotypic). a2 y, = ?????
Estimation of Predicted breeding value
The mixed model equations (MME) for the best linear unbiased estimator (BLUE) of Estimable function of b, and for the BLUP of a and pe, in matrix notation was as follows:
XX X"Z X"w xy
Z"X ZZ + A-1a1 Z' Z aA = Z y
W" X ws Z wW + Ia2 pA wy"
Where, A-1 is the inverse of the numerator relationship matrix,
a 1 = c2e / c2a and a2 = o2e / c2pe
Estimation of Accuracy of Predicted breeding value
The accuracy of predicted breeding values for each animal was assessed as follows:
R AA = (1- dj a) 2'
Where,
R A'A = the accuracy of prediction of the individual breeding values, dj = the jth diagonal elements of inverse of the appropriate block coefficient matrix standard error, (Se) was estimated by the following relation: Se = d j c2e. In addition, simple correlations between breeding values for litter traits and progeny weight were estimated.
RESULTS AND DISCUSSION
c a
Heritability estimates for body weight and average daily gain
Heritability estimates h2 for BW at 4, 6, 8, and 12 weeks were 0.65 ± 0.169, 0.09 ± 0.224, 0.01 ± 0.118 and 0.29 ± 0.143, respectively which were estimated from MTAM, and using all data. h2 are moderate for both breeds and ranged from 0.22 to 0.25 and 0.20 to 0.25 for G^ X V?, and V^ X G? crosses, respectively (Table 1). In addition, the moderate h2 for BW at weaning 0.23 and 0.22 for G^ X V?, and V^ X G? respectively, which suggested that the selection for weaning weight will give greater improvement for BW at marketing, thus, this could be situated as the endorsement goal of animal breeder. Furthermore, a little higher h2 of BW for G^ X V? than its reciprocal indicated the importance of using bucks of Saini Gabali to improve BW at different ages.
The extant results indicated that h2 estimates were higher for BW at weaning and decreased gradually, and then increased at older ages. The equivalent results were confirmed by Khalil (1986). Also, the moderate h2 for BW4, and BW12 suggested that the selection for weaning weight will give a greater improvement in BW at marketing. Similarly, according to El-Kelany (2005) who concluded that the additive genetic variances at younger age (4 weeks) for the five breeds (New Zealand White, California, Basucat, Flander and Black and Baladi) were beneath those at older age (8 weeks). This could be a direct result of non-added substance of genetic impacts and changeless environmental impacts at 4 weeks than at 8 weeks. In addition, Anous (2000) found that h2 estimates for BW at 4, 6, 8 and 10 weeks old were 0.67, 0.81, 0.98 and 0.67, respectively, and concluded that the selection for BW at earlier ages may be convenient procedure for improving early rabbit growth. The present estimate of h2 for weaning weight were exceeding those reported before (0.224-0.26) (Argente et al., 1999; Garcia and Baselga, 2002). These differences among results may be attributed to differences in sampling errors, available number of observations, methods of analysis and statistical model used. Contritely, low h2 for BW at various ages of California were 0.17 and 0.18 for 8 and 12 weeks old, while h2 were
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0.16 and 0.19 for daily gain during the period of 4 to 8 and 8 to 12 weeks old, respectively (Gharib, 2008). At the present study, the favorable estimates of h2 for post-weaning growth traits were underneath those obtained by other scientists using the AM ranged from 0.30 to 0.72 (Iraqi et al., 2002). The acquired outcomes were correspondingly to the small sample' size of progeny per generation, second the inadequacy of progeny per sire, and third to the non-randomness in the allocation of progeny within sire group and sampling errors (Khalil et al., 2000). Intestinally, it will be an encouraging factor to enrich growth performance of these standard breeds raised in hot climates through the selection of sires in future. Regarding to gain weight, the present estimates of ADG among different ages were lower than those reported by many authors working on various rabbits' breeds and ranged from 0.018 to 0.61. These results implied that the post-weaning ADG tends to be low to moderate heritable. Alike body weights, the h2 for post-weaning ADG estimated from sire components were inferior to those estimated from dam components, which it was due to the maternal effect on BW from birth to weaning. These results corresponded to the previous studies where maternal genetic effects were realized significantly positive for the favors of V-Line dams, BW8 and BW12 (Abou Khadiga et al., 2008). The V-line had an unfavorable maternal genetic effect on the BW at 32 days old (ranging from 54.3 to 86.0 gram). In addition, Orengo et al. (2009) reported that maternal genetic effects were significant for BW at 60 days. Furthermore, the estimate of h2 was higher for BW8 weeks than other ages, and the selection of the animals would be more effective at 8 weeks of age to improve post-weaning growth traits in Gabali rabbits (Iraqi, 2008).
Table 1. Estimates of heritability for body weights, and average daily gains from weaning to marketing weight for Gabali X V-line, and its reciprocal cross by animal model_
Heritability (h2± SE)
Traits All data Gabali x V- line (Gâ X VÇ) V- line x Gabali (Vâ X GÇ)
BW4 0.65 i 0.16 0.23 i 0.07 0.23 i 0.07
BW6 0.09 i 0.22 0.25 i 0.10 0.25 i 0.10
BW8 0.01 i 0.11 0.25 i 0.05 0.25 i 0.05
BWj2 0.29 i 0.14 0.22 i 0.02 0.22 i 0.02
ADG4-8 0.01 i 0.13 0.36 i 0.135 0.15 i 0.135
ADG4-J2 0.12 i 0.06 0.38 i 0.069 0.61 i 0.069
ADG8-!2 0.08 i 0.05 0.08 i 0.055 0.04 i 0.055
BW: Body weight at 4, 6, 8, and 12 weeks of age (BW4, BW6, BW8, and BW12, respectively). ADG4-8: 4-8 weeks interval, 4-12 weeks (ADG4-12), and 8-12 weeks (ADG8-12) Average daily gain between
Genetics and environmental correlations
The MTAM analysis of variance and covariance were performed on the data of V-Line and Saini Gabali breed to derive estimates of direct additive genetic (rg) and environmental correlations (re) among different traits studied. Genetic correlation for both BW and ADG at distinctive ages were positive, and ranged from 0.02 to 0.77, and 0.04 to 0.76, respectively. The highest genetic correlation was 0.76 between ADG442 and ADGs-10 (Tables 2 and 3). These results possibly explained by that the selection for higher BW at weaning would cause an associated increase in marketing body weight. Assessments of environmental correlation among BW at different ages were negative, except the re between BW8, and BW12 were positive (0.08, 0.124), but not significant (Table 2). Also, re among ADG in different intervals were lower in most incidents than the genetic correlation (Table 3). The present findings advocated that using early information for higher BW selection at weaning would cause a correlated increase in marketing BW. Comparable results were acquired where rg ranged from 0.31 to 1.0 (El-Kelany, 2005; Khalil et al., 2000). Moreover, Shebl et al. (1997) stated that rg amongst BW at 8, 12 and 16 weeks of age, and the daily gain (8 and 12 weeks) for New Zealand White (NZW) and Gabali line (G) were positive. The current estimates of rg indicated that BW8 was more correlated than BW4, and BW6 compared to rg for BW4 with that at BW6, and BW12, indicating that high weaning weight was associated with heavier body weight as BW4, and BW12. Enab et al. (2000) found that rg were positive and generally high in Cal and NZW breeds at all ages (4, 8, and 12 weeks). Also, it was noted that rg in general tended to diminish the value as the intervals between two ages increased in both breeds (Enab et al., 2000). Prospectively, rg between ADG in different ages were positive; the highest rg between ADG4-12 and ADG8-10 indicated that the selection of animals that have heavy BW at 4 weeks of age, would increase BW at marketing in the next generation. Analogously, Shebl et al. (1997) found that the rg between BW8, and ADG8-12 weeks was lower than the corresponding rg between BW12 and ADG in the same period. Regarding to estimates of environmental correlation (re) concerning BW at different ages were negative, except for re between BW8 and BW12 which was positive, but not significant. In addition, re between average daily gains in different ages were lower than the genetic correlation in most incidents (Table 3). In other incidents, both rg and re had the same indication, and they were not distinct in magnitude. Accordingly, this tendency might possibly be owing to several physiological mechanisms.
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Table 2. Estimates of genetic (above diagonal) and environmental (below diagonal) correlations among weekly body weights from weaning to marketing weight in rabbits as estimated by Multi-trait animal model_
Correlated traitsa BW4 BW6 BW8 BW!2
BW4 0.14 0.51 0.20
(0.683) (2.257) (0.346)
BW6 -0.17 0.77 0.02
(0.231) (1.472) (0.579)
BW8 -0.29 -0.38 0.02
(0.196) (0.114) (1.207)
BWj2 -0.75 0.00 0.08
(0.122) (0.139) (0.124)
a Body weight at 4, 6, 8, and 12 weeks of age (BW4, BW6, BW8, and BW12, respectively);
Table 3. Estimates of genetic (above diagonal) and environmental (below diagonal) correlations between post weaning
average daily gains in rabbits as estimated by Multi-trait animal model
Correlated traitsa ADG4-8 ADG4-12 ADG8-!0 ADG8-!2
ADG4-8 0.13 - (2.298) 0.53 (5.410) 0.08 (2.637)
ADG4-J2 -0.18 (0.081) - 0.76 (0.338) 0.04 (0.385)
ADG8-!0 0.01 0.35 (0.076) (0.071) - 0.02 (0.360)
ADG8-!2 -0.09 1.00 (0.119) (0.026) 0.34 (0.084) -
a Average daily gain between 4-8 weeks interval (ADG4.8), 4-12 weeks (ADG4_i2), 8-10 weeks (ADG8.i0), and 8-12 weeks (adgs-i2).
Breeding values
Body weight
Estimates of minimum and maximum predicted breeding values (PBV), and their accuracies (r) for BW at various ages estimated from does breeding values (DBVs), bucks breeding values (BBVs) and progeny breeding values (PBVs) were presented in table 4. The range of DBV for BW at four, five, six, eight, 10, and 12 weeks of age were 360, 584, 541, 561, 600, and 232 gram, respectively, and that of BBV were 219, 247, 250, 213, 270, and 290 gram, respectively. Whereas the range of PBV was 517, 575, 550, 505, 535 and 548 gram for BW at 4, 5, 6, 8, 10, and 12 weeks of age, respectively. Table 5 shows the higher numbers of PPVs which were obtained from crossing between bucks of G^ X V?, and V^ X G?, respectively. The present results indicated that for both breeds, progeny had higher breeding values for BW at different ages (4, 8, 10, and 12 week). Also, the predicted breeding values achieved from G^ X V? cross are superior to those attained from reciprocal cross. Then, it is important to recognize that there was a potentially moderate improvement in BW at weaning and marketing (12 weeks) in G^ X V? raised in adverse environmental through sire selection. According to high ranges in breeding values for most body weights obtained Does and progeny, indicated the importance of selection of doe and progeny in the second line to improve BW for different ages. The similar results were also obtained by Khalil et al. (2000) and Sabra et al. (2001). Moreover, Khalil et al. (2000) concluded that among all sires in NZW and California breeds, percentage of sires with positive estimates of sire transmitting ability (46.20 to 61.10%) for BW (At 5, 6, 8, 10 and 12 weeks). From the genetic point of view, there is a potentially for a moderate improvement in post-weaning growth traits in NZW and Cal rabbits raised in adverse environmental through sire selection. In addition, Sabra et al. (2001) noticed that the PBV for BW at 8 weeks and 12 weeks of age ranged from 269 to 303 grams, and from -315 to 324 grams in NZW, and Z-line. Also, wide variations in PBV of BW between the two strains was found to be in favor of Z-Line rabbits (Iraqi et al., 2002). The exactness of lowest and greatest evaluations of PBV were for the most part higher in NZW than those in Z-Line.
Average daily gain
Estimates of minimum and maximum PBV with standard errors (SE) and their accuracies (r) for ADG between 4 to 8 weeks (ADG4-8), between 4-12 weeks (ADG4-12), between 8 to 10 weeks (ADG8-10), and between 8 to 12 weeks (ADG8-12) estimated from DBVs, and PBVs are presented in table 6. The range of DBVs were 6.29, 1.845, 8.31, and 11.38 gram for ADG4-8, ADG4-12, ADGs -10, and ADGs-12, respectively. Also, the BBVs for the above-mentioned traits were 3.08, 1.32, 6.11, and 15.29 gram, respectively. Whereas, the range of PBVs were 6.95, 1.86, 6.16, and 15.36 gram, respectively. The present results indicated that the range of predicted breeding values of does for most traits studied were higher than those of progeny and sires. The obtained results revealed the importance of dams, since it gives the higher range of breeding values and selection of dams for the next generation in maternal line would place emphasis on good genetic maternal effects. Similar results have found where the genetic trend of post-weaning daily gain in lines A and V rabbits, had positive trend, small for line V, and considerably higher for line A (Baselga and Garcia, 2002).
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Table 4. The ranges of predicted breeding values for does, bucks and progeny in weekly body weights from weaning to marketing for Gabali, V-line rabbits and their crosses as estimated by multi-trait animal model
Predicted breeding valuesb
Traitsa) Minimum DI Vs Maximum Minimum BB ÎVs Maximum Minimum P B Vs Maximum
BV SE R BV SE r BV SE r BV SE R BV SE r BV SE r
BW4 -0.207 0.10 0.88 0.153 0.05 0.37 -0.143 0.04 0.73 0.076 0.07 0.92 -0.201 0.06 0.68 0.316 0.08 0.85
BWS -0.241 0.05 0.37 0.343 0.11 0.88 -0.174 0.05 0.73 0.073 0.08 0.91 -0.223 0.07 0.00 0.352 0.11 0.85
BW6 -0.214 0.06 0.35 0.327 0.11 0.87 -0.184 0.05 0.71 0.066 0.08 0.79 -0.217 0.07 0.00 0.333 0.11 0.83
BW8 -0.228 0.06 0.00 0.333 0.83 0.81 -0.116 0.05 0.00 0.097 0.08 0.89 -0.197 0.07 0.00 0.314 0.11 0.82
BW10 -0.254 0.07 0.00 0.346 0.13 0.80 -0.141 0.06 0.39 0.129 0.12 0.89 -0.229 0.08 0.00 0.323 0.13 0.84
BWx2 -0.113 0.08 0.00 0.119 0.14 0.83 -0.100 0.06 0.38 0.198 0.13 0.88 -0.212 0.09 0.00 0.336 0.14 0.83
a> Body weight at 4, 5, 6, 8, 10, and 12 weeks of age (BW4, BW5, BW6, BW8, BWi0, and BWi2, respectively), b> DBVs: Doe predicted breeding value, BBVs: buck predicted breeding value, PBVs: progeny predicted breeding value, BV: Breeding value, SE: Standard error, R/r: Accuracies of breeding value.
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Rabie T, Nowier A, Abou-Zeid A and Khattab A (2020). Assessment of Genetic Capability for Post- Weaning Growth Traits of Reciprocal Cross between Gabali and V-Line Rabbits Using an Animal Model. World Vet. J., 10 (3): 405-413. DOI: https://dx.doi.org/10.36380/scil.2020.wvj50
Table 5. Predicted breeding values for higher number of progenies of body weight (g) at different ages (4, 8, 10 and 12 weeks of age) for Gabali x V-line and its reciprocal cross
Gabali x V- line X VÇ)
V- line x Gabali (V^ X GÇ)
No. BW4a) BWS BW!0 BW12 No. BW4 BWS BW!0 BW!2
100 -293 -272 -197 -185 351 -185 -177 -223 214
101 426 292 601 350 357 120 210 153 112
216 212 164 253 282 354 136 035 150 164
274 326 279 285 113 356 040 101 080 122
277 503 395 552 301 369 013 078 039 059
279 328 270 320 133 370 104 162 151 173
282 117 111 067 060 384 024 088 051 069
301 303 270 237 169 385 -113 -106 -166 240
387 673 550 676 454 401 071 095 -110 -152
910 478 404 440 318 406 220 240 304 374
915 353 259 445 406 410 036 026 007 053
960 190 170 145 065 441 097 092 128 145
967 134 117 107 041 487 087 039 082 090
4006 209 155 263 203 489 418 384 573 739
4008 678 599 544 378 498 133 192 175 168
4009 -071 -060 -068 -393 4055 472 525 654 801
4016 130 020 423 257 4056 354 480 446 390
4098 270 220 270 068 5001 044 104 060 038
5002 188 207 268 347
) Body weight at 4, 8, 10, and 12 weeks of age (BW4, BW8, BWi0, BWi2, respectively)
Table 6. The ranges of predicted breeding values for does, bucks and progeny in post-weaning average daily gain for Gabali, V-line rabbits and their crosses as estimated by multi-trait animal model
Predicted breeding valuesb
DBVs BBVs PBVs
Traitsa) Minimum Maximum Minimum Maximum Minimum Maximum
BV SE R BV SE r BV SE r BV SE R BV SE r BV SE r
ADG4-8 -2.850 3.58 0.16 3.444 4.460 0.61 -1.421 3.12 0.40 1.656 4.15 0.72 -4.542 3.77 0.32 2.404 4.30 0.63
ADG4-J2 -1.004 0.67 0.17 0.841 0.92 0.69 -0.702 0.66 0.41 0.612 0.85 0.74 -0.840 0.34 0.33 1.024 0.88 0.63
ADG8-!0 -3.735 2.73 0.14 4.577 3.49 0.63 -2.862 2.60 0.36 3.245 3.30 0.68 -2.886 0.303 0.28 3.273 3.82 0.59
ADG8-!2 -4.590 4.31 0.23 6.786 6.58 0.77 -10.25 3.88 0.51 5.032 5.81 0.82 -8.327 5.15 0.43 7.033 6.090 0.72
1 Average daily gain between 4-8 weeks interval (ADG4.8), 4-12 weeks (ADG4-12), 8-10 weeks (ADG8.10), and 8-12 weeks (ADG8.12); DBVs: Doe predicted breeding value, BBVs: buck predicted breeding value, PBVs: progeny
predicted breeding value
411
Rabie T, Nowier A, Abou-Zeid A and Khattab A (2020). Assessment of Genetic Capability for Post- Weaning Growth Traits of Reciprocal Cross between Gabali and V-Line Rabbits Using an Animal Model. World Vet. J., 10 (3): 405-413. DOI: https://dx.doi.org/10.36380/scil.2020.wvj50
DECLARATIONS
Competing interests
There is no conflict of interest.
Authors' contributions
Rabie T., Khattab A., and Abou-Zeid A. designed research. Rabie T. wrote the paper. Khattab A. and Nowier A.
analyzed the data. All authors read and approved the final manuscript.
Acknowledgments
The support of the Department of Animal Production and Fish Resources, Faculty of Agriculture, Suez Canal
University, Ismailia, and the Department of Animal Production, Faculty of Agriculture, Tanta University are gratefully
acknowledged.
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