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1.
The results presented are part of a beef × dairy cross breeding experiment in which Simmental, Charolais, Danish Red and White Cattle (DRK), Romagnola, Chianina, Hereford, Blonde d'Aquitaine and Limousin bulls are crossbred with cows of Danish Red Cattle (RDM) and Black Pied Danish Cattle (SDM).Young bulls were slaughtered at 300 kg (712 months of age on average), 12 months and 15 months of age. Samples of m. longissimus dorsi and m. semitendinosus from 305 animals were examined by a taste panel, by chemical analysis and measurements of colour, by shear force, and by adhesion measurements.Sire breed had a significant influence on chemical composition and colour in both muscles. Taste panel scores and shear force values showed that all sire breeds gave tender meat in the longissimus dorsi. Significant differences in tenderness between sire breeds were found only for the semitendinosus, where Hereford crossbreeds obtained the lowest scores, and Limousin and Blonde d'Aquitaine crossbreeds the highest. Corresponding differences between sire breeds were found for adhesion value, collagen content and solubility of collagen in semitendinosus.Meat quality differences are discussed in relation to early and late maturing breeds.  相似文献   

2.
The experimental design and objectives are outlined for a crossbreeding experiment with European beef breeds as sire breeds and RDM (Danish Red), SDM (Black Pied Danish) and Danish Jersey as dam breeds.Results from a calving survey of 1006 single calvings are presented. Gestation length, birth weight and calving performance were strongly influenced by breed of sire, breed of dam and sex of calf. The variation in gestation length seemed to have only a slight effect on birth weight. The variation in birth weight had a strong effect on calving performance.The ranking of the sire breeds in descending order according to the frequency of unasisted calvings (which varied from 70 to 26 percent) was as follows: Hereford, Limousin, Danish Red and White Cattle, Simmental, Blonde d'Aquitaine, Chianina, Charolais and Romagnola.  相似文献   

3.
The maternal values of various maternal dairy, local and beef breeds used in beef crossing are analyzed and compared on field progeny test data, including 374 Limousin, 94 Blond d'Aquitaine and 256 Charolais sires with, respectively: 16 765, 4 696 and 12 824 pure and cross-bred offsprings.The traits studied were female calving difficulty score and frequency, birth and 75-day weight, conformation score of calves and the product of the last two variables. Additive effects of the different dam breeds (13, 11 and 13 breeds, respectively mated to Limousin, Blond d'Aquitaine and Charolais sires) were estimated separately for each sire breed by the least squares method (taking into account sex and calving parity effects) and then expressed as deviations from the French Friesian estimate.On score and frequency of calving difficulties, dam breeds were classed in the following groups (from best to worst): (1) Aubrac, Tarentaise; (2) Salers, Gasconne, Abondance, Montbéliarde; (3) Charolaise, Normande, Brune des Alpes, Limousine; (4) Frisonne, Blonde d'Aquitaine, Pie-Rouge de l'Est. Rating on 75-day weight and postnatal growth showed a superiority of dairy breeds over beef and local breeds which is more pronounced when the potential growth of the sire breed is high. The conformation score clearly distinguishes beef, dual-purpose, dairy and local breeds in decreasing order of merit while this ranking remains unchanged for beef synthetic value when dam breeds are crossed with Limousin and Blond d'Aquitaine sires. Large-size dairy breeds such as Pie-Rouge de l'Est, Brune des Alpes and Normande crossed with Charolais permit a better expression of potential growth in the calves.These results show that the utilization of suckling dam breeds in crossing with paternal beef breeds involves complementarity between maternal and paternal components in order to obtain optimum balance between size, growth traits (growth potential, milk production) and muscular conformation.  相似文献   

4.
The main results from beef breed comparisons carried out in the United Kingdom during the past 15 years are reviewed. Comprehensive information is now available from the Meat and Livestock Commission's Beef Breed Evaluation programme, complemented by the results from several smaller trials evaluating imported breeds.In most trials, breeds have been compared at similar levels of carcass subcutaneous fat percentage estimated in different ways (equal SF). The sire breeds with larger adult body size were generally slower maturing, taking longer to reach the equal fatness slaughter point; they also grew faster. They ate more food which tended to balance the extra output, resulting in a range of only 10% in feed cost per unit live weight gain. Hereford crosses had consistently high feed efficiencies across the trials. Limousin crosses followed by Aberdeen Angus, Charolais and Sussex crosses had the highest carcass meat percentages and Canadian Holsteins the lowest: the range at equal SF was four percentage units. Continental breed crosses had a marginal advantage in the proportion of their total meat occurring in the higher-priced cuts.  相似文献   

5.
Birth, weaning, feedlot and carcass traits were evaluated on 1,181 calves sired by Charolais and Limousin bulls out of eight crossbred dam groups (Hereford X Angus, Angus X Hereford, Simmental X Angus, Simmental X Hereford, Brown Swiss X Angus, Brown Swiss X Hereford, Jersey X Angus, Jersey X Hereford). Calves were born in the spring over a 4-yr period during which dams ranged from 3 to 8 yr of age. Charolais-cross calves were 2.7 kg heavier (P less than .01) at birth and had a 9.9% higher (P less than .01) incidence of difficult calvings and 4.6% greater (P less than .05) preweaning death loss than did Limousin crosses. Charolais-sired calves out-gained Limousin-sired calves by 31 g/d (P less than .01) from birth to weaning and were 9 kg heavier (P less than .01) at weaning. After weaning, calves were self-fed a finishing diet and slaughtered as each animal attained an estimated carcass grade of low Choice. Charolais-cross calves gained 60 g/d faster (P less than .01) than Limousin crosses, were fed 6.8 fewer d and were 17.3 kg heavier (P less than .01) at slaughter. Feed efficiency was similar for both sire breeds. On a grade-equivalent basis, Charolais crosses produced 7 kg heavier (P less than .01) carcass and had 22 g more carcass weight per day of age (P less than .01). Charolais crosses had slightly less internal and external fat. Dressing percentage was higher for Limousin cross calves (64.6 vs 63.9%, P less than .01). Longissimus muscle area and carcass cutability were similar for crosses of both sire breeds.  相似文献   

6.
F. Szab  I. Dkay 《Livestock Science》2009,122(2-3):271-275
Longevity of beef cows defined as the length of productive life from first calving to culling was estimated in this study. Data from 1800 cows belonging to Hereford, Angus, Simmental, Charolais, Limousin and Blonde d' Aquitaine breeds were analysed using survival method. The results indicate effects of breed, calving season, and calving difficulty on longevity (P < 0.05); however, herd, age of the cow at first calving, sex and weaning weight of their calves did not affect (P > 0.05) the length of productive life. Hereford had significantly greater (10.3 years) estimated length of productive life than Angus (8.1 years), Simmental (7.9 years), and Charolais (7.1 years), which had similar estimated longevity. Limousin (5.9 years) and Blonde d' Aquitaine (5.2 years) were similar in estimated longevity, but less than the other breeds studied. Cows that calved first in spring or summer were estimated to have longer productive life (7.2 years and 9.9 years) and less risk of early culling than those calving in autumn (5.7 years) and in winter (5.1 years). Longer productive life (6.2 years) was estimated across breeds for cows calving without assistance or with a little assistance (6.9 years) compared to those needing veterinary assistance (2.8 years) or having stillbirth (4.6 years). The results highlight that breed, calving season and calving difficulty of beef cows may have important effects on length of productive life. Special attention should be devoted to these effects.  相似文献   

7.
Evaluations of steer and heifer progeny from a diallel mating design of Simmental, Limousin, Polled Hereford and Brahman beef cattle over 5 yr are presented. Traits evaluated included final weight, hot carcass weight, ribeye area, 12th rib fat thickness, marbling score, yield grade, dressing percentage and percentage of kidney, pelvic and heart fat. Progeny of Simmental sires were heavier at slaughter than those with Brahman sires (P less than .05), but no differences were found for carcass weight. Dressing percentage was higher for Limousin crosses compared with progeny of other sire breeds (P less than .05). Similar results were found for dam breeds, except that progeny of Limousin dams had heavier carcasses with a higher dressing percentage (P less than .05) than Brahman crosses. Crosses of Limousin and Simmental had larger ribeye areas (P less than .05) compared with calves of the other breeds. Progeny of Polled Hereford dams had higher marbling scores and were fatter than progeny of dams of other breeds (P less than .05). Heterosis estimates were significant for all Brahman crosses for final weight, carcass weight and ribeye area, but these contrasts were negligible for other traits. Estimates of general combining ability were positive and significant for Simmental for final weight, carcass weight, ribeye area and marbling score and were significant and negative for Limousin for final weight, fat thickness and yield grade. Maternal values were generally small.  相似文献   

8.
The first objective of this study was to test the ability of systems of weighing and classifying bovine carcasses used in commercial abattoirs in Ireland to provide information that can be used for the purposes of genetic evaluation of carcass weight, carcass fatness class, and carcass conformation class. Secondly, the study aimed to test whether genetic and phenotypic variances differed by breed of sire. Variance components for carcass traits were estimated for crosses between dairy cows and 8 breeds of sire commonly found in the Irish cattle population. These 8 breeds were Aberdeen Angus, Belgian Blue, Charolais, Friesian, Hereford, Holstein, Limousin, and Simmental. A multivariate animal model was used to estimate genetic parameters within the Holstein sire breed group. Univariate analyses were used to estimate variance components for the remaining 7 sire breed groups. Multivariate sire models were used to formally test differences in genetic variances in sire breed groups. Field data on 64,443 animals, which were slaughtered in commercial abattoirs between the ages of 300 and 875 d, were analyzed in 8 analyses. Carcass fat class and carcass conformation class were measured using the European Union beef carcass classification system (EUROP) scale. For all 3 traits, the sire breed group with the greatest genetic variance had a value of more than 8 times the sire breed group with least genetic variance. Heritabilities ranged from zero to moderate for carcass fatness class (0.00 to 0.40), from low to moderate for carcass conformation class (0.04 to 0.36), and from low to high for carcass weight (0.06 to 0.65). Carcass weight was the most heritable (0.26) of the 3 traits. Carcass conformation class and carcass fatness class were equally heritable (0.17). Genetic and phenotypic correlations were all positive in the Holstein sire breed group. The genetic correlations varied from 0.11 for the relationship between carcass weight and carcass fatness class to 0.44 for the relationship between carcass conformation class and carcass fatness class. Carcass weight and classification data collected in Irish abattoirs are useful for the purposes of genetic evaluation for beef traits of Irish cattle. There were significantly different variance components across the sire breed groups.  相似文献   

9.
The objective of this study was to quantify the effect of inbreeding on carcass quality, growth rate, live conformation measures, and calving performance in purebred populations of Charolais, Limousin, Simmental, Hereford, and Angus beef cattle using data from Irish commercial and pedigree herds. Variables analyzed are reflective of commercial farming practices. Inbreeding was included in a linear mixed model as either a class variable or a linear continuous variable. Nonlinear effects were nonsignificant across all traits. Inbred animals had decreased carcass weight and less carcass fat. The effects of inbreeding were more pronounced in the British beef breeds. Effects for carcass weight ranged from -0.87 kg (Charolais) to -1.90 kg (Hereford) per 1% increase in inbreeding. Inbred Charolais and Hereford animals were younger at slaughter by 3 and 5 d, respectively, per percentage of increase in inbreeding, whereas the effect of inbreeding on age at slaughter differed significantly with animal sex in the Limousin and Angus breeds. Inbred Limousin and Angus heifers were younger at slaughter by 5 and 7 d, respectively, per percentage of increase in inbreeding. Continental animals were more affected by inbreeding for live muscling and skeletal conformational measurements than the British breeds; inbred animals were smaller and narrower with poorer developed muscle. Calf inbreeding significantly affected perinatal mortality in Charolais, Simmental, and Hereford animals. The effects were dependent upon dam parity and calf sex; however, where significant, the association was always unfavorable. Dam inbreeding significantly affected perinatal mortality in Limousin and Hereford animals. Effects differed by parity in Limousins. Inbred first-parity Angus dams had a greater incidence of dystocia. Although the effects of inbreeding were some-times significant, they were small and are unlikely to make a large financial effect on commercial beef production in Ireland.  相似文献   

10.
The objective of this study was to determine the inbreeding levels and to analyze the pedigree of Irish purebred populations of Charolais, Limousin, Hereford, Angus, and Simmental beef cattle, as well as the Holstein-Friesian dairy breed. Pedigree analyses included quantifying the depth of known pedigree, average generation intervals, effective population size, the effective number of founders, ancestors, and founder genomes, as well as identifying the most influential animals within the current population of each breed. The annual rate of increase in inbreeding over the past decade was 0.13% (P < 0.001) in the Hereford, 0.06% (P < 0.001) in the Simmental, and 0.10% (P < 0.001) in the Holstein-Friesian breeds. Inbreeding in the other breeds remained relatively constant over the past decade. Herefords had the greatest mean inbreeding in 2004, at 2.19%, whereas Charolais had the lowest, at 0.54%. Over half of each purebred population in 2004 was inbred to some degree; the population with the greatest proportion of animals inbred was the Hereford breed (85%). All 6 breeds displayed a generation interval of approximately 6 yr in recent years. In the pure-bred females born in 2004, the 3 most influential animals contributed between 11% (Limousin) and 24% (Hereford) of the genes. Effective population size was estimated for the Hereford, Simmental, and Holstein-Friesian only, and was 64, 127, and 75, respectively. The effective number of founders varied from 55 (Simmental) to 357 (Charolais), whereas the effective number of ancestors varied from 35 (Simmental and Hereford) to 82 (Limousin). Thus, despite the majority of animals being inbred, the inbreeding level across breeds is low but rising at a slow rate in the Hereford, Simmental, and Holstein-Friesian.  相似文献   

11.
A total of 528 birth and 475 weaning records collected over a 3-yr period were analyzed to evaluate the productivity of several beef cattle breed crosses. The calves were produced by artificial insemination using 17 Brahman, 15 Chianina, 15 Maine Anjou and 16 Simmental sires bred to Angus and Hereford dams varying in age from 3 to 11 yr. Breed-of-sire effects were important (P less than .05 to P less than .001) for gestation length, birth weight, conformation score and condition score, but were not observed for birth weight adjusted for gestation length, percentage calving assistance, survival rate or weaning weight. Brahman crosses had the longest gestation lengths, being 4.7 d longer than Simmental crosses, which were the shortest in length. Chianina crosses were the heaviest at birth and experienced the most calving difficulty. Simmental crosses had the highest survival rate. Although breed-of-sire differences were observed in conformation score, the difference was less than one-third of a grade between the highest-scoring Simmental crosses and the lowest-scoring Brahman and Chianina crosses. Brahman crosses had the highest condition scores, being approximately one-third of a grade higher than the lowest-ranking Chianina crosses. Differences among the sire breeds for weaning weight were surprisingly small, varying only 3 kg from the heaviest to lightest breed-of-sire groups. Angus dams had shorter gestation lengths (P less than .001) and produced calves that weighed more at weaning (P less than .001) and scored higher for conformation (P less than .001) and condition (P less than .001) score than Hereford dams.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
Calving records for daughters of 667 Record of Performance tested sires were examined to study factors related to age at first calving. For the 3025 heifers analyzed, mean age (± SD) at first calving was 791.5 ± 161.6 days (26.4 ± 5.4 months). There were significant effects of the breed of sire on age of heifer at first calving. Daughters of Angus sires calved earlier than daughters of Charolais, Hereford, Limousin, and Simmental sires. Mean ages at first calving for daughters of Hereford, Limousin, and Simmental bulls were significantly (p < 0.05) correlated with the sire's end-of-test age-adjusted scrotal circumference, but these correlations were not significant when farm effects were controlled. It appears that unknown herd level factors are more important in determining age at first calving in Ontario herds than using early maturing sires as determined by scrotal circumference measurements.  相似文献   

13.
Variation between- and within-breeds was evaluated for accretion of weight from birth to 7 yr of age and hip height at 7 yr for 1,577 cows sired by Angus, Brahman, Brown Swiss, Charolais, Chianina, Gelbvieh, Hereford, Jersey, Limousin, Maine Anjou, Pinzgauer, Sahiwal, Simmental, South Devon, and Tarentaise and from either Angus or Hereford dams. Parameters from Wt = A (1 - Be-kt) were estimated by nonlinear regressions and provided estimates of mature body weight (A) and rate of weight accretion relative to change in age (k) for each cow. Actual weight at birth, linear adjusted weights at 200, 365, and 500 d of age, ratios of these weights to mature weight, and height at the hip at 7 yr were analyzed. Beyond 20 mo, weights were adjusted to a constant condition score within breed of sire. Variance and covariance components were derived for breed (sigma 2 b), sires within breed (sigma 2 s), and progeny within sire (sigma 2 w). For all traits, the sigma 2 b estimate of genetic variance ranged from two to four times greater than the variance component for sigma 2 s. Between-breed heritabilities were .91 +/- .27 and .54 +/- .17 for A and k, respectively. Estimates of within-breed heritability for these two traits were .61 +/- .11 and .27 +/- .09. Estimates, both between- and within-breed, of the genetic correlation between A and k were moderate to large and negative; those between A and weights at 200, 365, and 500 d and height at maturity were large and positive. Selection for immediate change in measures of growth would be most effective among breeds. Sufficient direct genetic variation exists between breeds to enhance breed improvement of growth characters through breed substitution. Greater opportunity to alter the shape of the growth curve exists through selection for within-breed selection than through breed substitution.  相似文献   

14.
Milk yield data were collected by weigh-suckle-weigh procedures at approximately 14, 28, 56, 84, 112, 138, 156, 184, and 212 d postpartum for mature Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Red Poll, Pinzgauer, and Simmental cows over a 4-yr period. Individual cows were fed at one of four energy intake levels. Parameters characterizing lactation curves for 431 lactations from 179 cows were estimated by nonlinear regression. Differences due to breed, level of energy intake, and the two-factor interaction between breed and level of ME allowance for scale and shape parameters of lactation curves and derived estimates for time of peak lactation, yield at time of peak lactation, and for total yield for a 210-d lactation period were evaluated. Breed and energy intake level were significant sources of variation for all traits. Pooled over energy levels, daily yields at time of peak lactation of Braunvieh, Gelbvieh, and Pinzgauer were greater (P less than .05) than those of Angus, Charolais, Hereford, and Limousin. Simmental and Red Poll were intermediate. Total lactation yield of the Braunvieh exceeded (P less than .05) that of all other breeds with the exception of Gelbvieh. Hereford produced less milk than (P less than .05) the other breeds. The response in yields at time of peak lactation as energy allowances increased for Braunvieh, Charolis, Gelbvieh, Limousin, and Pinzgauer cows were linear and resulted in higher yields at this time. Linear increases in total 210-d yield and times of peak lactation were observed for all breeds with the exception of Hereford.  相似文献   

15.
Feedlot traits, carcass traits and distribution of commercial cuts of crossbred intact male progeny (n = 556) from young and mature Hereford, Red Poll, Hereford X Red Poll, Red Poll X Hereford, Angus X Hereford, Angus X Charolais, Brahman X Hereford and Brahman X Angus dams were evaluated. First-calf heifers were bred to Red Angus bulls; Santa Gertrudis sires were used for each cow's second and third breeding seasons. Calves from these young dams were slaughtered at 13 mo. Calves of mature dams were all sired by Limousin bulls and slaughtered at 12 mo. Dam breed was a major source of variation in most bull traits. Progeny of Brahman-cross dams were inferior (P less than .01) in daily gain, final weight, carcass weight and in edible cuts/day of age compared with progeny from Bos taurus dams. Intact male progeny of Angus X Charolais dams ranked highest in longissimus area, cutability, and edible cuts/day of age. The range of dam breed means in percentage of steak, roast, bone-in cuts (chuck short ribs and back ribs), short plate and thin cuts, and lean trim was just over 1%. Greater variation among dam breeds existed in fat measurements. Analyses in which Hereford-Red Poll diallel data for young dams and mature dams were combined showed positive maternal heterosis for dressing percentage (P less than .05), carcass weight (P less than .05), carcass weight/day of age (P less than .05), estimated carcass fat (P less than .05), fat thickness (P less than .01) and marbling score (P less than .01). Reciprocal effects were inconsequential. Results illustrate the importance of dam breed-type effects in formulating breeding strategies for commercial beef herds.  相似文献   

16.
Data for gestation length, birth weight, calving difficulty (percent assisted) and survival from birth to weaning were analyzed from 4,639 calves by 290 sires of 14 Bos taurus breeds (Hereford, Angus, Jersey, South Devon, Limousin, Simmental, Charolais, Red Poll, Brown Swiss, Gelbvieh, Maine Anjou, Chianina, Pinzgauer and Tarentaise) mated to Hereford and Angus cows. The calves were produced over a 7-yr period in a germ plasm evaluation program. Variance components were estimated for breed of sire (sigma 2b), sire within breed of sire (sigma 2s) and progeny within sire (sigma 2w) random effects. Estimates of sigma 2b and sigma 2s direct genetic variance were similar for gestation length and calf survival. Estimates of sigma 2b genetic variance were greater than for sigma 2s for birth weight and calving difficulty. Estimates of total heritability [h2t = 4(sigma 2b + sigma 2s)/(4 sigma 2b + sigma 2s + sigma 2w)] and within-breed heritability (h2w = 4 sigma 2s/sigma 2s + sigma 2w) indicated that gestation length (h2t = .77, h2w = 64) and birth weight (h2t = .79, h2w = .46) are under a high degree of direct genetic control, calving difficulty (h2t = .42, h2w = .21) is under a moderate degree of direct genetic control and calf survival (h2t = .11, h2w = .07) is under a low degree of direct genetic control. Estimates of genetic correlation for between (rb) - and within-breed (rg) sources of genetic variation were comparable in direction, but tended to be stronger between than within breeds.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
Breed and sire effects on the percentage of female births over time in five breeds of registered beef cattle were studied. Breed groups were managed separately, and matings were performed by artificial insemination and natural service. The percentage of female births was included in the study for sires that were used for at least 2 yr and sired at least seven progeny. Progeny of 48 Angus, 7 Charolais, 19 Horned Hereford, 17 Polled Hereford, and five Red Poll sires were used in the study. The numbers of birth years by breed were 33, 21, 31, 31, and 15 for Angus, Charolais, Horned Hereford, Polled Hereford and Red Poll, respectively. Variances for breed and sire were partitioned for percentage female births using a nested random effects analysis of variance. Breed effects for percentage of female births were 0.46% of total variance. Sire effects accounted for 0.27% of total variance. Means for percentage female births by breed were 50 ± 1% for Angus, 47 ± 3% for Charolais, 48 ± 2% for Horned Hereford, 52 ± 2% for Polled Hereford, and 49 ± 5% for Red Poll. Although sire variance was minimal, there were some sires that consistently produced a greater or lesser number of females over time. These results suggest that more research is needed to determine the factors that influence sex ratio in cattle due to its economic importance to the industry.  相似文献   

18.
Thyroid, adrenal, pituitary and brain weights were first determined in 1971 in 492 market weight cattle representing purebred Shorthorns and crosses of “foreign” breeds, Charolais, Simmental and Limousin with Hereford, Angus and Shorthorn. Thyroid weights were also determined in a similar group of 433 cattle the following year. The data were reported on a per 100 kg body weight basis and analyzed within the subgroups of breed of sire, breed of dam and location.

The average thyroid weight per 100 kg of body weight for males within subgroups over the two years ranged from 3.99 to 8.71 g, while that for steers ranged from 3.81 to 4.41 g. The average thyroid weight for a group of 18 Limousin sired heifers was 3.71 g. The average adrenal weight per 100 kg of slaughter weight ranged from 3.66 to 4.20 g in the males and from 3.66 to 3.86 g in the steers. Pituitary weight per 100 kg body weight at slaughter ranged from 486-511 mg in bulls and from 469-510 mg in steers. Average brain weight ranged from 85.5 to 97.3 g in males and from 92.2 to 94.1 g in steers.

Breed differences existed only for the pituitary gland, with Simmental sired males and steers having heavier glands than Charolais sired males and steers.

Sex differences were significant for the thyroid and the brain. Thyroids of males were generally heavier than those of steers, while brains of steers were heavier than those from males.

Thyroid, adrenal and brain weights were significantly different between two genetically similar purebred herds of Shorthorns.

  相似文献   

19.
草原红牛微卫星DNA多态性的研究   总被引:1,自引:0,他引:1  
为了更好地培育和改良肉用草原红牛,利用草原红牛、夏洛莱牛、西门塔尔牛、利木赞牛、蒙古牛基因组DNA,用8对微卫星引物进行PCR扩增,并将扩增产物置于1.5%琼脂糖电泳进行观察,如有所需的带则转入8%聚丙烯酰胺变性凝胶(PAGE)中电泳分离,绘制指纹图谱。结果表明微卫星标记方法是一种理想的研究方法。  相似文献   

20.
Plasma corticoids, potassium and sodium, thyroid activity and hemoglobin and hematocrit values were determined at slaughter over a period of four years in 1612 animals representing the following sire groups: Short-horn, Charolais, Simmental, Limousin, Red Angus, Beefmaster, Brown Swiss, Chianina and Jersey. Differences among years and among breeds of sire were significant for all the parameters studied. Hematocrit values were the highest in females and the lowest for entire males, while hemoglobin levels were the lowest in females and the highest for bulls. Plasma corticoid levels were lower for entire males as compared to steers and heifers. Plasma sodium and potassium levels were the highest for females and the lowest entire males. The values reported in this study for several blood components, based on a large number of animals, could serve as clinical guides and as a basis for further research.  相似文献   

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