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1.
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   

2.
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   

3.
Beef production characteristics of 254 intensively fed young bulls are described. The results are part of a beef × dairy crossbreeding experiment, where sires of eight European beef and dual-purpose breeds were used on cows of RDM (Danish Red Cattle) and SDM (Black Pied Danish Cattle).Daily gain and feed conversion were influenced by the sire breeds. Charolais, Blonde d'Aquitaine and Simmental crosses showed the highest daily gain, followed by Romagnola, Danish Red and White, Chianina, Limousin and Hereford crosses.Carcass composition and carcass conformation were strongly influenced by sire breed with Blonde d'Aquitaine and Limousin crosses producing the most valuable carcasses followed by Chianina, Charolais, Romagnola, Simmental, Danish Red and White and Hereford crosses in descending order.The analysis showed a sire breed × weight/age interaction in carcass composition traits, due to sire breed differences in maturity. That demonstrates the importance of serial slaughtering in breed comparison experiments. Hereford and Limousin produced the earliest maturing crosses and Danish Red and White and Blonde d'Aquitaine the latest maturing crosses.  相似文献   

4.
Breed means and differences for weight (CW, n = 19,851), height (CH, n = 14,553), and condition scores (CS, n = 19,536) recorded in four seasons per year were evaluated for 881 cows ranging from 2 to 7 yr of age from Cycle I of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center. Cows were straightbred Herefords and Angus and topcrosses from mating of Hereford, Angus, South Devon, Jersey, Simmental, Limousin, and Charolais sires to Hereford and Angus dams. The model included cow age, season of measurement, and their interactions, with year of birth, pregnancy-lactation (PL) code, and breed group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as covariate. Model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Data were analyzed by REML. Differences due to breeds of sire were significant for all traits. Differences were generally maintained across ages, with few interchanges in ranking through maturity. Rankings were in the following order: Jersey (lightest and shortest), Hereford-Angus (and reciprocal), Limousin, South Devon, Simmental, and Charolais (heaviest and tallest). The only exception was that Limousin-sired cows were heavier than South Devon-sired cows after 5 yr of age. Cows sired by breeds of British origin tended to be lighter than breeds of continental European origin. Adjustment for condition score changed estimates of breed differences. Rankings of breed groups, however, were generally the same for actual weight and weight adjusted for condition score. Results indicated that the part of the differences in weight due to differences in condition were of small magnitude. Differences tended to increase when adjusted for condition score, especially in contrasts of continental vs British breeds. Differences among breed groups for height followed differences for weight closely.  相似文献   

5.
Two previously identified single-nucleotide polymorphism markers located within the micromolar calcium-activated neutral protease gene (CAPN1) were evaluated for their association with variation in meat tenderness using one commercial sample of Simmental x Angus crossbred calves and one multibreed, crossbred research herd. The commercial sample included 362 animals sired by 23 registered Simmental bulls bred to unregistered Angus cows and represented current industry animals in which to test the predictive merit of the markers. The second sample was a research herd including 564 steers from the Germplasm Evaluation Cycle VII population at the U.S. Meat Animal Research Center, produced with semen from popular sires of the seven Bos taurus beef breeds with the most registrations in the United States (Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental) on Angus, Hereford, and MARC III cows. These animals form a relatively outbred population that constituted a stringent test of the predictive merit of the genetic markers, although small groups were half-sibs. Warner-Bratzler shear force measurements were used to determine tenderness phenotypes for all animals. The populations were genotyped for two markers that predict variation at amino acid positions 316 and 530 of the mu-calpain polypeptide, produced by the CAPN1 gene. Minor allele frequencies for markers 316 and 530 in the commercial sample were 0.17 and 0.37, respectively, and in the Cycle VII animals, were 0.20 and 0.28, respectively. Both markers showed association with shear force in the commercial sample (P = 0.04) and the Cycle VII population (P = 0.02), supporting the hypothesis that they represent potential markers to aid selection for improved meat tenderness in commercial populations of beef cattle in the United States.  相似文献   

6.
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   

7.
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   

8.
Computer models were used to simulate the feedlot segment of an integrated beef production system. Five breeds, Angus (A), Charolais (C), Hereford (H), Limousin (L), and Simmental (S), in three mating systems, pure-breeding and two- and three-breed rotational crossbreeding, were evaluated for feedlot and carcass performance. Breed data were taken from the literature. Feeder calves (steers and non-replacement heifers) entered the feedlot at 205 d of age. After a 35-d adjustment period, calves were custom-fed to four slaughter end points: 440 d, 457 d, 288-kg carcass weight, or low Choice. Cattle were fed to requirements (megacalories of ME). Input costs included feed and nonfeed expenses (purchase prices, transportation, yardage, and medicinal fees). Carcass values were $2.65 and $2.54/kg of carcass weight for steer and heifers, respectively, between 272 to 318 kg. Over- or underweight carcasses were discounted $.60/kg. At the 440-d end point, Select grade steer and heifer carcasses were discounted an additional $.22 and $17/kg, respectively. Biological efficiency was measured as megacalories of ME/kg of gain, and economic efficiencies were measured as input costs per kilogram of carcass weight, input costs per kilogram of lean weight, and input costs per carcass value. Continental breed combinations (C and S) were most efficient at age- and weight-constant end points for megacalories of ME per kilogram of gain and for input costs per carcass value and most efficient at all end points for input costs per kilogram of carcass weight and input costs per kilogram of lean weight. British breed combinations (A) were most efficient at a fat-constant end point for megacalories of ME per kilogram of gain and input costs per carcass value. Therefore, choosing breed combinations for feedlots depends on slaughter end point and measures of efficiency.  相似文献   

9.
Abstract

The contribution of three candidate genes to the variation in meat tenderness was tested in muscle samples from 243 pure-bred, young, beef bulls of Angus, Charolais, Hereford, Limousin and Simmental breeds, raised in Swedish commercial herds. The animals were genotyped for single nucleotide polymorphisms (SNPs) in the calpain 1 (CAPN1), calpastatin (CAST) and leptin genes. The frequent calpain 1 CAPN1:c.947G>C G allele showed an unfavourable association with tenderness. The calpastatin CAST:c.155C>T T allele, which was the most common allele, showed a favourable association with Warner–Bratzler shear force (WBSF) and compression tests. An association was observed between the leptin UASMS2C>T SNP and compression tests.  相似文献   

10.
三种杂交牛产肉性能研究   总被引:1,自引:0,他引:1  
试验旨在研究相同营养水平日粮对不同杂交肉牛生产性能及肉品质的影响.以10月龄10头西杂、10头夏杂、6头安杂牛为试验材料,以美国NRC肉用小公牛营养需要为饲养标准,进行255 d强度育肥试验,试验后进行屠宰及肉质分析.测定三种杂交牛的日增重、胴体重、屠宰率、牛肉脂肪酸、粗蛋白质、氨基酸等含量,并进行差异比较.结果发现各分析指标在各组间虽有差异,但均未达显著水平,综合分析后认为安格斯杂交牛的育肥效果最好,其次是西门塔尔杂交牛,最后是夏洛来杂交牛.  相似文献   

11.
The objective of this study was to characterize breeds representing diverse biological types for postweaning growth and carcass composition traits in terminal crossbred cattle. Postweaning growth and carcass traits were analyzed on 434 steers and 373 heifers obtained by mating F1 cows to Charolais sires. Maternal grandsires represented Hereford, Angus, and MARC III (1/4 Hereford, 1/4 Angus, 1/4 Pinzgauer, and 1/4 Red Poll) dams to Hereford or Angus (British Breeds), Norwegian Red, Swedish Red and White, Wagyu, or Friesian breeds. Breed groups were slaughtered serially in each of 2 yr (2002 and 2003). Postweaning ADG, slaughter weight, hot carcass weight, dressing percentage, percentage Choice, LM area, marbling score, USDA yield grade, fat thickness, retail product yield (percentage), retail product weight, fat yield (percentage), fat weight, bone yield (percentage), and bone weight were analyzed. Maternal grandsire breed was significant (P < 0.05) for all traits except dressing percentage, percentage Choice, and LM area. Marbling score for animals with Norwegian Red, Wagyu, Swedish Red and White, British Breeds, and Friesian inheritance was 550, 544, 532, 530, and 515, respectively (SEM = 8). Retail product weight for these animals was 224, 211, 227, 223, and 223 kg, respectively (SEM = 2 kg). Maternal granddam breed was not significant for any of the traits analyzed. Grandsire breed effects can be optimized by selection and use of appropriate crossbreeding systems.  相似文献   

12.
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   

13.
Important differences are noted between the New Zealand and European cattle industries, in terms of both breeds and farming systems. Under pasture feeding, experimental data strongly suggest that selection and genetic evaluation for growth performance should be based on weight-for-age rather than on post-weaning weight gains. Carcass merit is more appropriately measured by the yield of trimmed boneless retail cuts than by accepted commercial grades.Relative to the nationally predominant Angus beef breed, research results demonstrate an advantage in final and carcass weight per animal of 5–10% for the Hereford and 20–30% for the Friesian, with the superiority being approximately halved in crossed with the Angus. In terms of weaning performance, the Friesian dam is greatly superior, the Hereford slightly inferior, to the Angus. Heterosis for growth traits is of the order of 5%.In crosses over Jersey cows the Charolais sire is superior to the Hereford but not to the Friesian for total meat output. Carcasses from the dairy breeds and dairy x beef crosses slaughtered at the same age contain a higher bone percentage and are less acceptable on traditional export grading standards than those of the British beef breeds, but nevertheless achieve high output and quality of lean meat.Preliminary results from current large-scale trials suggest that the larger European breeds have potential for improving growth rate and meat yield in crosses with local Angus and Hereford cattle but are more prone to difficult calvings and show later sexual maturity.  相似文献   

14.
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   

15.
不同品种及排酸对育肥牛肉嫩度影响的研究   总被引:1,自引:0,他引:1  
为了研究品种对牛肉嫩度的影响以及在不同排酸时间中肉嫩度的变化,试验在内蒙古肉牛主产区选择了16月龄的红白花西门塔尔牛、夏洛莱牛、安格斯牛、黄白花西门塔尔牛等品种高代杂种牛以及草原红牛和蒙古牛,在相同饲养管理条件下育肥180 d后屠宰并测定肉的嫩度。结果表明:安格斯牛肉嫩度较其他品种肉牛好,蒙古牛肉嫩度较其他品种肉牛差;但经过一定的排酸期后,嫩度均可达较好水平。  相似文献   

16.
Data collected from steer and bull progeny, fed to a constant final feedlot weight over 11 yr, were used to estimate heterosis in post-weaning feedlot growth and carcass traits in two-way and three-way rotational crossing systems and a breed composite from crossing Hereford, Angus and Charolais breeds. Steer and bull progeny from matings of beef x Brown Swiss-cross sires and dams also were compared with the straight beef breeds and beef crosses. Growth traits evaluated were initial weight on test, 112-d weight, total feedlot average daily gain and total days from initial to final weight. Carcass traits included hot carcass weight, dressing percentage, rib eye area, 12th-rib fat thickness, kidney, pelvic and heart fat, yield grade and marbling score. Heterosis estimates for calves of all crossing systems were significant for initial and 112-d weight and for saving of days in the feedlot, but not for average daily feedlot gain. Heterosis estimates were small and nonsignificant for most carcass traits except for fat traits in specific crosses. Males from Hereford and Angus sires mated to Angus x Hereford dams had higher (P less than .10) backfat than did the parental average. Male progeny from Charolais ranked higher (P less than .10 to P less than .01) than calves from Hereford and Angus sires for most growth traits. Progeny from Charolais sires were more desirable (P less than .10 to P less than .01) for traits related to cutability, but they had less (P less than .05 to P less than .01) marbling than calves of Angus sires.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
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   

18.
上世纪70年代以来锡林郭勒盟先后引进安格斯、利木赞、夏洛来、西门塔尔等肉牛品种改良蒙古牛.分析测定了不同品种杂交一代公母牛及蒙古牛6月龄、18月龄和30月龄体重的变化规律.结果安蒙、利蒙、夏蒙、西蒙杂一代6月龄公母犊平均体重分别比同龄蒙古牛增加37.87 kg、40.60 kg、66.35 kg和43.71 kg,分别提高32.75%、35.11%、57.37%和38.0%.18月龄公母牛平均体重分别比同龄蒙古牛增加78.75 kg、96.73 kg、107.72 kg和100.59 kg,分别提高35.84%、44.02%、49.03%和45.78%.30月龄公母牛平均体重分别比同龄蒙古牛增加67.07 kg、84.86 kg、110.18 kg和116.26 kg,分别提高19.86%、25.13%、32.62%和34.42%.  相似文献   

19.
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   

20.
为了研究不同肉牛品种杂交改良西门塔尔杂种牛的效果,筛选出产肉量高、肉质好、抗逆性强的品种杂交组合,为大规模开展杂交提供依据,试验采用红安格斯、利木赞、夏洛莱(法系)、德国黄牛4个品种牛,分别杂交西门塔尔杂种母牛,产犊后从每个杂交组合中选择11头断奶小公牛,在相同饲养管理条件下持续育肥至18月龄,并进行屠宰和肉质评定。结果表明:红安西杂组合杂交效果最好,其次是利西杂及夏西杂,德黄西杂组合杂交效果较差。说明在生产实际中,如果采用断奶小公牛持续育肥至18月龄时出栏、屠宰,应优先选择红安格斯×西门塔尔杂交组合。  相似文献   

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