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排序方式: 共有147条查询结果,搜索用时 31 毫秒
1.
Lubritz DL Eisen EJ Robison OW 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》1993,110(1-6):363-373
SUMMARY: Effects of PMSG and genotype on various measures of reproductive efficiency were investigated. Prenatal data were obtained at 40 d of gestation from 96 gilts representing four genotypes. Data on Duroc (D), Yorkshire (Y), Synthetic (Large White × Landrace) (SYN), and Crossbred Duroc × Yorkshire (XB) gilts were collected from January, 1990 through May, 1991. Litter size (LS) data were collected from 482 farrowings of siblings. Treatment with exogenous hormones significantly increased number of corpora lutea (CL), number of embryos (EN), ovum wastage, (OVWS) and embryo length (ELG). Breed group differences (P < .05) were detected for natural ovulation rate, hormone-induced ovulation rate, CL, OVWS, ELG, embryo weight, ovum success, uterine length, ovary weight, range and variance of within-litter embryo weight (RWT and VWT), and litter size born alive. Natural ovulation rates for D, Y, SYN and XB were 10.46 ± 1.61, 12.64 ± 1.41, 14.10 ± .99 and 10.90 ± 1.47, and hormone-induced ovulation rates were 15.00 ± 1.53, 17.69 ± 1.40, 19.43 ± 1.17 and 12.19 ± 1.43, respectively. Range and variance of within-litter embryo length were not affected by either treatment or genotype. Increases in RWT and VWT observed in D and XB gilts after PMSG treatment did not adversely affect embryo survival to 40 d gestation. Significant genetic differences existed for litter size at birth. The PMSG treatment and interactions with PMSG were not significant for litter size born alive. Breed groups seem to differ for CL and EN in response to PMSG but only Yorkshire showed any response in LS (P < .10). Although PMSG increased ovulation rate in siblings by 4.06 ova and number of embryos at 40 d gestation by 1.87 compared with control gilts, there were no differences in litter size born alive due to PMSG treatment. The increase in ovulation rate and number of embryos generated by PMSG seems to be negated by fetal losses occurring both before and after 40 d of gestation. ZUSAMMENFASSUNG: Einflüsse von Stutenserum-Gonadotropin (PMSG) auf Reproduktionsmerkmale von vier Genotypen bei Jungsauen Einflüsse von PMSG und Genotyp auf verschiedene Merkmale der Reproduktion wurden untersucht. Daten wurden am 40. Tr?chtigkeitstag von 96 Jungsauen von vier Genotypen-Duroc (D), Yorkshire (Y), Synthetik (Edelschwein × Landrasse (SYN)) und Kreuzungen-Duroc × Yorkshire (XB) zwischen Januar 1990 und Mai 1991 erhoben. Wurfgr??e (LS) wurden von 492 Würfen von Geschwistertieren erhoben. Behandlung mit exogenem Hormon steigert signifikant die Zahl der Gelbk?rper (CL), Zahl der Embryonen (EN), Ovarverlust (OVWS) und Embryol?nge (ELG). Differenzen zwischen Genotypen wurden für natürliche und hormoninduzierte Ovulationsrate, CL, OVWS, ELG, Embryogewicht, Embryoerfolg, Geb?rmutterl?nge, Ovargewicht, Streuungsbereich und Varianz des Embryogewichtes von Wurfgeschwistern (RWT und VWT) und Zahl lebendgeborener Ferkel erhoben. Die natürlichen Ovulationsraten für D, Y, SYN und XB waren 10,46 ± 1,61, 12,64 ± 1,41, 14,10 ± 0,99 und 10,90 ± 1,47, und die hormoninduzierten 15,00 ± 1,53, 17,69 ± 1,40, 19,43 ± 1,17 und 12,19 ± 1,43. Streuungsbereich und Varianz zwischen Embryonenl?nge eines Wurfes wurden weder durch Behandlung noch Genotyp tangiert. Steigerungen in RWT und VWT in D und XB Jungsauen nach Hormonbehandlung hat Embryoüberleben bis 40 Tage nicht beeintr?chtigt. Signifikante genetische Unterschiede existieren zwischen Wurfgr??e bei Geburt. Hormonbehandlungen und Interaktionen mit Genotypen waren für die Wurfgr??e nicht signifikant. Rassengruppen scheinen für CL und EN im Hinblick auf Hormonbehandlung sich zu unterscheiden, aber nur Yorkshire zeigten Reaktion bei LS (P < .1). Obwohl das Hormon die Ovulationsrate um 4,06 Eier und Zahl der Embryonen bei 40 Tagen um 1,87 gegenüber Kontrollsauen vergr??erte, verblieben keine Unterschiede in Wurf gr??e. Die Steigerung der Ovulationsrate und Zahl der Embryonen nach Hormonbehandlung scheint durch F?talverluste vor und nach 40 Tagen Tr?chtigkeit eliminiert zu werden. 相似文献
2.
J. Robison N. Arora Y. Yamasaki M. Saito J. Boone B. Blacklock S. Randall 《Journal of Agronomy and Crop Science》2017,203(6):553-561
Soybean has been considered a cold intolerant species; based largely upon seed germination and soil emergent evaluations. This study reports a distinct acquisition of cold tolerance, in seedlings, following short acclimation periods. Diversity in cold responses was assessed in eight cultivars of Glycine max and six accessions of G. soja. All varieties of soybean significantly increased in freezing tolerance following acclimation. This study indicates soybean seedlings are indeed capable of sensing cold and acquiring cold tolerance. Germination rates after cold imbibition were negatively correlated with maturity group, but positively correlated with cold acclimation potential in G. soja. Seed fatty acid composition was varied between the species, with Glycine soja accessions containing about 2‐times more linolenic acid (18:3) than G. max. Furthermore, high levels of linoleic acid (18:2) in seeds were positively correlated with germination rates following cold imbibition in G. soja only. We suggest that domestication has not impacted the overall ability of soybean to cold acclimate at the seedling stage and that there is little variation within the domesticated species for ability to cold acclimate. Thus, this brief comparative study reduces the enthusiasm for the “wild” species as an additional source of genetic diversity for cold tolerance. 相似文献
3.
Characterization of a line of pigs previously selected for increased litter size for RBP4 and follistatin 总被引:1,自引:0,他引:1
C.D. Blowe K.E. Boyette M.S. Ashwell E.J. Eisen O.W. Robison & J.P. Cassady 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(6):389-395
The objective of this study was to determine if selection response for increased litter size in pigs could be partially attributed to three type 1 marker loci coding for genes known to affect litter size: oestrogen receptor (ESR), retinol‐binding protein 4 (RBP4) and follistatin (FS). In the high litter size line (LS), pigs from the largest litters, based on number of pigs born alive (NBA), were retained to parent the next generation. A randomly selected control line (LC) was maintained. Gilts were reared in litters of 10 pigs or less to minimize maternal effects. Pigs were measured at generations 10–12. Additional traits scored were number of fully formed pigs (NFF) and number of mummified fetuses (MUM). Breeding values for NFF and NBA were greater (p < 0.05) in LS than LC in generations 11 and 12, but no significant line differences were found for MUM. The A allele of the ESR locus was fixed in both lines. After adjustment for effects of genetic drift, frequency of the two alleles segregating for the FS and RBP4 loci did not differ significantly between lines. No significant additive or dominance effects of the FS markers were detected for NFF, NBA and MUM in either LS or LC. Response to selection for increased litter size could not be attributed to effects at the ESR, RBP4 or FS loci. 相似文献
4.
Genetic differences in natural vs hormone-induced ovulation rates were compared in immature female mice from five lines that had undergone long-term single-trait and antagonistic index selection for litter size and(or) 6-wk BW. Lines used were control (K); high litter size (L+); high BW (W+); low litter size and high BW (L-W+); and high litter size and low BW (L+W-). Natural ovulation rate at a mean age of 34.3 d and hormone-induced (5 IU of pregnant mare's serum gonadotropin followed 2 d later by 5 IU of human chorionic gonadotropin) superovulation rate at a fixed age of 31 d were obtained. Total number of eggs ovulated was affected by line (P less than .001), treatment (P less than .001), and line x treatment interaction (P less than .001). Line differences were subsequently tested within treatment because of the significant line x treatment interaction. Line differences were important (P less than .001) for natural ovulation, hormone-induced ovulation, and response to hormones. Mean natural ovulation rates for K, L+, W+, L-W+, and L+W- were 14.1, 19.8, 15.1, 13.6, and 16.4, respectively. Selection changed ovulation rate by 40, 16, 7, and -4% in the L+, L+W-, W+ and L-W+ lines, respectively (P less than .01). Hormone-induced ovulation rates in K, L+, W+, L-W+, and L+W- were 32.3, 24.6, 19.6, 20.9, and 22.1, respectively. Exogenous hormones increased ovulation by 18.2, 4.8, 4.6, 7.3, and 5.7 ova for K, L+, W+, L-W+, and L+W-, respectively (P less than .001). Lines with lower natural ovulation rates had higher responses to superovulation. Increased ovulation rate due to treatment ranged from 24.3% in L+ to 129% in K. These results indicate significant differences among lines in ovarian response to exogenous hormones. 相似文献
5.
D. J. Fairbanks K. W. Burgener L. R. Robison W. R. Andersen E. Ballon 《Plant Breeding》1990,104(3):190-195
Quinoa (Chenopodium quinoa Willd) is an important domesticated food crop of the Andean highlands with potential as an alternative crop elsewhere. Among its most attractive characteristics are the quantity and favorable amino acid balance of the seed proteins. The objective of this study was to characterize quinoa seed proteins by electrophoretic mobility, solubility fractionation, and genetic variability from a wide genetic base. Electrophoretic profiles of denatured albumin, globulin, prolamin, and glutelin solubility fractions demonstrated that quinoa seed polypeptides could be classified as either albumin or globulin with most predominant polypeptides in the globulin fraction. Insignificant amounts of protein were present in the prolamin fraction and all polypeptides in the glutelin fraction had identical electrophoretic mobilities to albumins and globulins. Three globulin polypeptides of 34.3, 35.6, and 36.2 kilodaltons in size were highly variable within and among the accessions examined and appear to be coded by at least two loci. Two-dimensional peptide mapping revealed that these three polypeptides were homologous. These highly variable markers could be used for identification and classification of germplasm and elucidation of systematics and genetic variability within the quinoa germplasm pool. All other major polypeptides were electrophoretically invariant among the accessions examined. 相似文献
6.
Enhancement of RAPD Analysis by Restriction-endonuclease Digestion of Template DNA in Wheat 总被引:1,自引:0,他引:1
C.R. Riede D.J. Fairbanks W.R. Andersen R.L. Kehrer L.R. Robison 《Plant Breeding》1994,113(3):254-257
Random amplified polymorphic DNA (RAPD) analysis has proven to be an effective procedure for molecular marker applications in plant breeding, although non-specific amplification may limit its utility in some species. The objective of this study was to determine the effectiveness of restriction-endonuclease digestion of template DNA for elimination of non-specific amplification and generation of heritable RAPD markers. Restriction endonucleases digested wheat DNA to completion in amplification buffer, suggesting that the restriction endonuclease can be added directly to the reaction mixture prior to amplification. A 1-h 37°C step was programmed into the thermal cycler for restriction-endonuclease digestion which was followed immediately by amplification. Non-specific amplification was reduced and DNA marker patterns were altered in digested samples when compared to undigested samples. Genetic segregation of two polymorphic markers tested in F5 inbred progeny fit expected 1:1 ratios. These results suggest that heritable DNA markers may be generated with reduction in non-specific amplification when restriction-endonuclease digestion of template DNA is conducted as part of the RAPD procedure. 相似文献
7.
8.
Prediction of performance of progeny from test station boars. 总被引:2,自引:0,他引:2
Data were obtained from 1,954 Duroc and 2,252 Yorkshire purebred and crossbred progeny sired by 34 Duroc and 32 Yorkshire boars, respectively. Boars were purchased from the North Carolina Swine Evaluation Station during August 1983 to December 1988. Boars were selected to represent high and low indexes at the test station. Progeny were raised and tested under conditions similar to commercial pig production at the Tidewater Research Station. For each breed of boar (Duroc and Yorkshire), breed type (purebred and crossbred), and sex (castrates and gilts) of progeny, regression coefficients of progeny traits on each sire trait were computed. Progeny traits were ADG, days to 104.3 kg BW (DAYS), backfat thickness (BF), and feed conversion ratio (FC). Sire traits were ADG, DAYS, BF, FC, and INDEX. Effects of boar test group and progeny test group were included in the models. Averaged over breed type and sex, a 25-unit (1 SD) increase in sire INDEX resulted in 14.5 g more ADG, 3.2 fewer DAYS, .57 mm more BF, and .017 lower FC in Durocs and 5.6 g more ADG, .01 more DAYS, .81 mm less BF, and .083 lower FC in Yorkshires. The low magnitude and variable signs of some regression coefficients suggested that predictions of progeny performance from performance of individual sires at the North Carolina Swine Evaluation Station were not very reliable. Differences between regressions for purebreds and crossbreds implied small correlations between the two breed types. Differences between Durocs and Yorkshires indicated that genetic parameters might not be the same for the two breeds. 相似文献
9.
Angus (A), Charolais (C), Hereford (H), Limousin (L), and Simmental (S) breeds were included in deterministic computer models simulating integrated cow-calf-feedlot production systems. Three mating systems were used: pure-breeding and two-and three-breed rotational crossbreeding. Breed information was taken from the literature. Herd sizes were unrestricted; however, 100 heifers were saved as replacements. Cows were removed for reproductive failure, age (greater than 10.5 yr), or death. Calves produced in the cow-calf segment were fed in a custom feedlot to four slaughter end points: 440 d, 457 d, 288-kg carcass weight, and low Choice. All animals were fed to requirements. Cull cows were slaughtered after weaning. Biological and economic efficiencies improved with crossbreeding; however, rankings of breed combinations depended on how efficiencies were measured (weight, lean, or value basis). Among purebreds, reproductive performance had a large influence on breed rankings at age and weight end points, whereas feedlot performance was important at the low Choice end point. Crossbred combinations involving British (A or H) and Continental (C or S) breeds were more efficient than other crossbred combinations at all end points. However, choosing specific breed combinations for integrated systems depends on slaughter end points, market end points (weight vs lean), and measures of efficiency (weight, lean, or value basis). 相似文献
10.
Ovulation rate, ovary weight, corpora lutea weight and uterine length were measured at 10 or 35 d of gestation in Duroc (199) and Yorkshire gilts (114). Embryos were counted at d 35. Yorkshires had significantly more corpora lutea than Durocs (13.6 vs 12.3 at d 10; 13.9 vs 12.4 at d 35). At d 10 breeds did not differ in uterine length, but by d 35 Duroc uteri were longer (P less than .01) than Yorkshire uteri (411 vs 375 cm) despite having fewer (P greater than .05) embryos (9.9 vs 10.5). Ovary weight did not differ between breeds at 10 or 35 d. Homogeneity analyses showed that the correlation matrices were significantly different between breeds at d 35 but not at d 10. In Durocs, high positive correlations existed between total embryo number and corpora lutea number (.57), ovary weight (.53) and corpora lutea weight (.25), whereas corresponding correlations were small in Yorkshires (.21, -.02 and -.03, respectively). In Yorkshires, strong negative correlations existed between total embryo survival and corpora lutea number (-.55), ovary weight (-.30) and corpora lutea weight (-.55), but in Durocs corresponding correlations were small (-.12, .14 and -.10, respectively). These results suggest that animal scientists should consider breed differences in levels of performance and its relationships among traits when designing or interpreting experiments. 相似文献