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1.
Centric fusion translocations in cattle: a review   总被引：3，自引：0，他引：3  
The incidence of centric fusion (Robertsonian) translocation in cattle breeds is reviewed. Thirteen different centric fusions have been identified in cattle, with few breeds carrying more than one translocation. Of the commercial breeds, Friesian-Holstein cattle appear to be free of translocations, while the Simmental is the only one which carries three translocations. The major effect of centric fusion is on fertility, causing unbalanced gametes and hence unbalanced zygotes to be formed, leading to early embryonic death. However, to discard all translocation-carrying animals may be misguided as they represent genetic variation and a source of desirable traits.  相似文献   

2.
科尔沁牛染色体14/24易位的初步研究   总被引：1，自引：0，他引：1  
对内蒙古哲盟地区的5头科尔沁牛进行了细胞遗传学检查。结果:3♀和1♂核型全为2n=60,可配成30对,29对常染色体和1对性染色体,性染色体X为大型亚中着丝粒,Y为小型亚中着丝粒染色体;1♂的核型为异常核型,59,XY,t(14:24)。14/24易位是单独发生的。  相似文献   

3.
A Robertsonian centric fusion between chromosomes 1 and 25 in Blonde d'Aquitaine cattle in New Zealand is reported. This fused chromosome is the same as the widely reported 1/29 translocation chromosome with the difference in the numbering arising from inconsistencies in the G and R-banded cattle karyotypes of the International System for Cytogenetic Nomenclature of Domestic Animals, 1989.  相似文献   

4.
Cytogenetic evaluation was made on 353 Simmental cattle (166 male, 187 female) from 113 herds in 26 states. One hundred thirty-eight (39%) were found to be heterozygous-positive for the 14/20 centric fusion chromosomal translocation, including 41 (25%) males and 97 (52%) females. One submitted heparinized blood sample from a Simbrah bull was found to be positive for 14/20 and 1/29 centric fusions. Sampling, which was based on requests, was highly selective. Thus, the 39% prevalence found was not representative of 14/20 centric fusion in the national Simmental breed. On the basis of our findings, cytogenetic evaluation of breeding stock was consistent with modern management practice.  相似文献   

5.
Quadrivalent pairing was observed by electron microscopy of the synaptonemal complex in pachytene spermatocytes in seven out of nine F1 Brahman × Hereford hybrid bulls. The presence of this chromosomal abnormality indicates that the carrier bulls were heterozygous for a reciprocal translocation, which could be contributing to the fertility problems of these hybrid cattle.  相似文献   

6.
A cytogenetical study was made of 9 descendants of a Charolais bull, heterozygous for a presumptive 1/29 translocation, three of the dams of some of these descendants, and three unrelated bulls which were mated to some of the descendants. Photographic karyotypes of Giemsa stained and C-banded chromosomes were prepared for each animal. The dams of the progeny showed no chromosomal abnormalities indicating that translocations were inherited from the sire. Three daughters of the Charolais bull and two of his grand daughters were heterozygous for the translocation, with a modal chromosomal number of 59, while the remaining three daughters and their progeny possessed normal karyotypes. No phenotypic abnormalities were observed in the animals examined. Measurements of the arms of the chromosomes suggested that the translocation chromosome (a large submetacentric) contained chromosomes 1 and 29. The submetacentric translocation chromosome had a single C-band, the two submetacentric X chromosomes showed no C-bands and each acrocentric autosome had a single C-band. All cattle heterozygous for the translocation showed normal fertility.  相似文献   

7.
Introduction Rapid development of the river buffalo physical map can be achieved by coupling its development to that of the cattle gene map. Syntenic conservation between cattle and buffalo has been demonstrated, mainly using somatic cell hybrids (de Hondt et al. 1991; El Nahas et al. 1993, 1996, 1998; de Hondt et al. 1997; El Nahta 1996; Oraby et al. 1977), and by using in situ hybridization as reviewed by Iannuzzi (1997). G- and R-banding comparisons between cattle (2n = 60) and river buffalo (2n = 50) chromosomes have revealed a large number of banding homologies between the two species, both at early-metaphase (Gupta and Ray -Chaudhury 1978; Di Berardino et al. 1981) and prometaphase stages (Iannuzzi et al. 1990). Banding homology indicates that the five river buffalo biarmed pairs originate from centric fusion translocation between two of ten homologous cattle autosomes, which is very supportive of the hypothesis that both species have a common ancestor (Wurster and Benirschke 1968). Based on cytological analysis and banding homology between cattle and buffalo chromosomes, the five biarmed chromosomes of the river buffalo BBU1, BBU2, BBU3, BBU4, BBU5 were thought to originate from fusion of cattle chromosome (BTA) 1/25; 2/23; 8/19; 5/28; and 16/29 respectively (Iannuzzi et al. 1990; Report of the Committee for the Standardization of Banded Karyotopes of the River Buffalo 1994). However, the analysis of synteny between molecular markers assigned to different cattle syntenic groups demonstrated that BBU1 results from fusion of BTA 1 and 27 rather than 1 and 25 (El Nahas et al. 1977). This called for expanding the analysis of syntenic relationships between marker loci to confirm the nature of the other biarmed buffalo chromosomes. The purpose of this study is to test synteny between markers in buffalo and to confirm the nature of the biarmed buffalo chromosomes 4 and 5, using marker loci and somatic cell hybrids.  相似文献   

8.
1株牛病毒性腹泻病毒分离毒株的基因组特征   总被引：3，自引：3，他引：0  
旨在从宁夏某奶牛群持续感染牛分离牛源牛病毒性腹泻病毒（BVDV）,并解析其基因组特征,为研究我国不同地区BVDV分离株遗传演化规律提供理论依据。利用BVDV抗原检测试剂盒检测宁夏回族自治区银川市某示范区的240头高产奶牛间隔两周的双份抗凝血,筛选持续感染牛,分离血液淋巴细胞制备裂解液接种牛肾细胞（MDBK）,分离鉴定获得BVDV株,克隆测序获得全基因组序列,比较分析其遗传演化关系。从该示范区高产奶牛筛选获得2头持续感染牛,分离获得1株非致细胞病变型BVDV,命名为NX2019/01。测序获得基因组全序列（12 107 nt）,其中ORF长11 703 nt,编码3 898个氨基酸。在基因组水平,NX2019/01株与我国SD-15、ZM-95、XC、LN-1等1m亚型分离株相似性较高（92.17%~93.84%）,但Erns、E1以及E2基因存在较大差异。示范区同群牛急性感染BVDV时,毒株E2蛋白N端编码区核苷酸突变可导致第9位或第67位氨基酸变异。重组分析表明,NX2019/01株E2基因179—288位核苷酸区段以及ZM-95株E1基因168位—E2基因332位核苷酸区段存在相似的重组信号,可能由主要亲本SD-15株与次要亲本LN-1株重组形成,表明NX2019/01株、ZM-95株在演化进程中与SD-15株以及LN-1株或早期流行的高度相似毒株存在密切关联。本研究从持续感染高产奶牛分离获得了牛源BVDV-1m亚型毒株,在基因组水平厘清了BVDV-1m亚型毒株的进化关系,并首次发现同亚型BVDV毒株基因同源重组,为进一步研究BVDV在我国的演化规律奠定了基础。  相似文献   

9.
To obtain the data concerning death losses due to stillbirth, neonatal death and diseases in cloned cattle derived from somatic cell nuclear transfer (SCNT) and their progeny produced by Japanese institutions, a nationwide survey was carried out in July-August, 2006. As a result, lifetime data concerning 482 SCNT cattle (97.5% of cattle produced in the country at that time) and 202 progeny of SCNT cattle were accumulated and the death loss of these cattle was analyzed. Although 1/3 of delivered SCNT calves died during the perinatal period due to stillbirth and neonatal death, incidence of death loss due to diseases in SCNT cattle surviving more than 200 days after birth seems to be the same as these in conventionally bred cattle. In contrast, progeny of SCNT cattle showed the same level in death loss as observed in conventionally bred cattle throughout their lifetime. These results suggest that robust health would be expected in SCNT cattle surviving to adulthood and their progeny.  相似文献   

10.
Field trials were carried out with two formulations of levamisole for treatment of chronic inflammatory lesions on the muzzle and teats of cattle, caused by Stephanofilaria okinawaensis in the enzootic area of the disease, Ishigaki Island, Okinawa Prefecture, Japan.Cattle were treated orally with levamisole hydrochloride (10% powder) at a dose of 7.5 g/100 kg of body weight once (64 cattle) or twice with an interval of 3 or 4 weeks (five cattle each). Lesions on the muzzle and tests disappeared or were reduced within 4 weeks of the first medication. In some cattle a sign of recurrence was observed 8 weeks after medication.Parasitological and histological examinations were carried out 1 week carried out 1 week (10 cattle), 4 weeks (12 cattle), and 8 weeks (13 cattle) after single oral administration of levamisole hydrochloride. No Stephanofilaria worms were detected at 1 week after medication. A small number of worms were detected at 4 weeks and more were observed 8 weeks after medication.A levamisole phosphate solution (18.2%) was injected subcutaneously once into one teat of each of three cattle, or twice into the neck with a 4-week interval between treatments (five cattle). The dose was 2 ml/teat (364 mg of active ingredient) or 2 ml/45 kg of body weight for the side of the neck. There was marked improvement as with oral medication with levamisole hydrochloride powder.  相似文献   

11.
Serum samples from 145 dairy and 65 beef cattle with reproductive disorders and 54 normally calving dairy cattle (controls) in Japan were tested for presence of Neospora caninum antibodies by use of an indirect fluorescent antibody test (IFAT, titer 1:200). Overall, seroprevalence of N. caninum was significantly higher (P < 0.001) in dairy cattle (20.0%, 29/145) than in beef cattle (1.5%, 1/65). In cattle which aborted, seroprevalence of N. caninum was significantly higher (P = 0.041) in dairy cattle (26.1%, 23/88, compared with controls (3.7%, 2/54)) than in beef cattle (5.0%, 1/20), indicating that neosporosis might be a more common problem in dairy cattle than in beef cattle in Japan. Seropositive cattle were 9.2 times more likely to abort compared to seronegative cows. Abortions associated with N. caninum seropositivity in this study were most frequently observed in the second trimester, and the mean gestational age of the fetuses aborted from seropositive dams was 5.7 months. In conclusions, N. caninum seems to be causing serious economic losses in the dairy industry in Japan. This is the first report on an objective comparison of seroprevalence of dairy and beef cattle with reproductive disorders in Asia.  相似文献   

12.
研究旨在比较大额牛和婆罗门杂交后代(GBF1)与云岭牛肉品质,评估大额牛杂交利用潜能。选择年龄相近、性别相同的GBF1牛和云岭牛进行育肥、屠宰,采集100个肉样冻存。以肉质较好的云岭牛肉为对照,检测GBF1牛肉的剪切力、失水率、系水力、蒸煮损失。结果表明,GBF1牛肩峰剪切力显著高于云岭牛(P< 0.05),其他部位肉剪切力两品种间没有显著差异(P> 0.05)。GBF1牛10个部位肉的平均剪切力、失水率、蒸煮损失分别为3.50 kg、24.15%、27.56%,低于云岭牛;平均系水力64.60%,高于云岭牛,但差异均不显著(P> 0.05)。由此可知,GBF1牛肉品质与云岭牛相似,且均较好。  相似文献   

13.
本研究旨在查明甘肃与宁夏地区奶牛衣原体的感染情况并分析影响其感染的风险因素。本试验采用间接血凝试验(IHA)方法检测了甘肃榆中(751份)、宁夏青铜峡(450份)和宁夏吴忠(456份)3个地方总计1 657份奶牛血清样品,并应用流行病学调查及统计学方法对影响奶牛衣原体感染的因素进行了分析。流行病学调查结果显示,奶牛衣原体抗体总阳性率为29.33%;应用logistic回归分析评估奶牛衣原体感染的风险因素,结果显示年龄和胎次不是显著风险因素(P>0.05),而地区因素是影响奶牛衣原体感染的风险因素(P<0.05)。奶牛衣原体抗体滴度最高达1:1 024。结果表明,甘肃和宁夏地区奶牛衣原体普遍流行。因此,应当提高对调查地区奶牛衣原体感染的重视,采取适当的综合控制方法和有效的管理措施以防控奶牛衣原体病,以保证奶牛养殖业的经济效益。  相似文献   

14.
The objective of the present investigation was to examine seroprevalence of Chlamydia in dairy cattle in Gansu and Ningxia areas, Northwest China, and to analyze the factors affecting Chlamydia infection in dairy cattle.Indirect hemagglutination assay (IHA) was used to detect antibodies against Chlamydia in 1 657 dairy cattle serum samples from Gansu and Ningxia areas.Epidemiological investigation and statistical methods were used to analyze the data.The results showed that the overall seroprevalence was 29.33%, logistic regression analysis was applied to evaluate the risk factors of Chlamydia infection in dairy cattle, and the results indicated that age and numbers of pregnancy of dairy cattle were not the significant risk factors (P>0.05), and were left out of the final model, however, region was considered as the main risk factor associated with Chlamydia infection (P<0.05).The highest titer was 1:1 024.In conclusion, the results of the present survey indicated the widespread of Chlamydia infection in Gansu and Ningxia areas.In order to ensure the economic benefit of dairy farming, we should pay more attention to Chlamydia infection in dairy cattle, and integrated control strategies and efficient management measures should be implemented to prevent and control Chlamydia infection in dairy cattle.  相似文献   

15.
This study describes the successful use of modified dorsolumbar epidural anesthesia with a fixed volume of anesthetic in a bovine referral center. Among the 130 Holstein cattle scheduled for flank surgery, 90 cattle received a mixed anesthetic consisting of 1 ml of xylazine hydrochloride and 3 ml of lidocaine hydrochloride by modified dorsolumbar epidural anesthesia. Eighteen cattle with dehydration and/or lameness received a mixed anesthetic containing 0.5 ml of xylazine and 3 ml of lidocaine. Infiltration anesthesia was performed in 22 cattle whose epidural space could not be reached in order to perform the flank surgery. The surgeries began about 12 min after the administration of the anesthetic and lasted for about 36 min. The modified method using a fixed volume of anesthetic was successfully introduced and effectively used in a bovine referral center. This modified method will allow veterinarians to save time and effort, thus lowering the cost of each surgery.  相似文献   

16.
Frequency of bovine Nramp1 (Slc11a1) alleles in Holstein and Zebu breeds   总被引：1，自引：0，他引：1  
Natural resistance against brucellosis in cattle is linked to the Nramp1 gene, which encodes a divalent cation transporter that localizes in the phagolysosome membrane in macrophages. Nramp1 gene in mouse plays a critical role in innate immunity favoring bacterial killing by macrophages in addition to its influence on adaptative immunity. Polymorphisms at the bovine Nramp1 3' untranslated region (3'UTR), detectable by Single Strand Conformational Analysis (SSCA), are associated with natural resistance against brucellosis. Such polymorphisms are associated with variation in the number of GT repeats. This study compared the frequency of Nramp1 3'UTR polymorphisms between Zebu and European bovine breeds. Eighty-one Holsteins (Bos taurus taurus) and 167 Zebu (Bos taurus indicus), including the following breeds: Nelore (n=95), Guzerá (n=37), and Gir (n=35), totaling 248 pure breed cattle studied. DNA extraction was performed using the guanidium protocol and genotyping was performed by SSCA. DNA from cattle considered genotypically resistant to brucellosis resulted in a single band (homozygous) with 175bp, corresponding to the 3'UTR with 13 GT pairs (GT13), whereas DNA from genotypically susceptible cattle generated one single band with 177bp (homozygous GT14) or double bands with both 175 and 177bp, or 175 and 179bp (heterozygous GT13/GT14 or GT13/GT15, respectively). A marked difference in the frequency of alleles was detected between the Zebu and Holstein cattle. Holsteins had an extremely homogeneous genotype, with 100% of the individuals with a GT13 genotype. In sharp contrast the Nelore breed had the most heterogeneous genotype with four allelic combinations, namely, homozygous GT13, homozygous GT14, heterozygous GT13/GT14, and heterozygous GT13/GT15. When the Zebu breeds were compared to each other, the only significant difference observed was the frequencies of the genotypes GT13 and GT14 between the Nelore and Guzerá breeds. The knowledge of allelic frequencies in different breeds of cattle may prove to be very useful in the future for planning breeding strategies for selection of resistant cattle.  相似文献   

17.
CASE DESCRIPTION: The owner of a herd of 74 Holstein-Friesian cattle reported decreased milk production, weight loss, and coughing among lactating cows. Owner-initiated antimicrobial treatment was unsuccessful; 1 lactating cow died, and 50% of the lactating cows had clinical signs of respiratory distress, such as tachypnea and coughing. CLINICAL FINDINGS: On the basis of history, physical examination findings, and fecal examination results, affected animals were determined to have Dictyocaulus viviparus (lungworm) infestation. The disease history suggested that the herd contained cows with subclinical patent lungworm infestations; after introduction of susceptible heifers, the pastures had become heavily infested with D viviparus and clinical problems subsequently developed in both newly introduced and resident cows. TREATMENT AND OUTCOME: Affected and unaffected heifers and adult cows were treated with a pour-on formulation of eprinomectin (0.5 mg/kg [0.23 mg/lb]). One animal died, but 2 weeks after treatment, clinical signs among affected cattle were markedly improved. Ten weeks after treatment, milk production improved from 23 kg/cow/d (51 lb/cow/d) to 28 kg/cow/d (62 lb/cow/d). CLINICAL RELEVANCE: The outbreak provides additional evidence that dictyocaulosis is becoming more common among adult dairy cattle, rather than almost exclusively affecting young stock. This may be attributable to anthelmintic use and management practices on dairy farms. Combined with anecdotal reports of an increase in the incidence of dictyocaulosis among adult cattle in North America, D viviparus infestation should be included as a differential diagnosis for decreased milk production, weight loss, and coughing among adult dairy cattle.  相似文献   

18.
Leptin as a predictor of carcass composition in beef cattle   总被引：8，自引：0，他引：8  
Our objective was to determine if serum concentrations of leptin could be used to predict carcass composition and merit in feedlot finished cattle. Two different groups of crossbred Bos taurus steers and heifers were managed under feedlot conditions near Miles City, MT. The first group consisted of 88 1/2 Red Angus, 1/4 Charolais, and 1/4 Tarentaise composite gene combination steers (CGC) harvested at the ConAgra processing facility in Greeley, CO. The second group (Lean Beef Project; LB) consisted of 91 F2 steers and heifers born to Limousin, Hereford, or Piedmontese by CGC F1 cows crossed to F1 bulls of similar breed composition and harvested at a local processing facility in Miles City, MT. Blood samples were collected approximately 24 h before harvest (CGC) or approximately 3 d before and at harvest (LB). No differences in serum concentrations of leptin were detected (P > 0.10) between Hereford, Limousin, or Piedmontese F2 calves nor between LB steers and heifers. Positive correlations (P < 0.01) existed between serum leptin and marbling score (r = 0.35 and 0.50), fat depth measured between the 12th and 13th rib (r = 0.34 and 0.46), kidney, pelvic, and heart fat (KPH) (r = 0.42 and 0.46), and quality grade (r = 0.36 and 0.49) in CGC and LB cattle, respectively. Serum leptin was also positively correlated with calculated yield grade for CGC steers (r = 0. 19; P = 0. 10) and LB cattle (r = 0.52; P < 0.01). Longissimus area was not correlated with serum leptin in CGC steers (r = 0.12; P > 0.10). However, a negative correlation existed between longissimus area and serum leptin in the LB cattle (r = -0.45; P < 0.01). Serum concentrations of leptin were significantly associated with carcass composition (marbling, back fat depth, and KPH fat) and quality grade in both groups of cattle studied and may provide an additional indicator of fat content in feedlot cattle.  相似文献   

19.
In 1999, 10 sporadic outbreaks of cattle foot-and-mouth disease (FMD) occurred in Taiwan. By the time, infection was limited to the Chinese yellow cattle (a native species of beef cattle in Mainland China), which did not develop vesicular lesions under field conditions. Five viruses isolates obtained from individual farms were confirmed to be the serotype O FMD virus (O/Taiwan/1999). During January-February 2000, however, this virus has spread to dairy cattle and goat herds, causing severe mortality in goat kids and vesicular lesions in dairy cattle. Partial nucleotide sequence of the capsid coding gene 1D (VP1) was determined for the virus isolates obtained in this study. Phylogenetic analysis of the VP1 sequences indicated that the O/Taiwan/1999 viruses shared 95-97% similarities to the virus strains isolated from the Middle East and India. The species susceptibility of the O/Taiwan/1999 virus was experimentally studied in several species of susceptible animals, showing that the virus did cause generalized lesions in dairy cattle and pigs, however, it would not cause vesicular lesions on the Chinese yellow cattle and the adult goats. These studies suggested that the O/Taiwan/1999 virus was a novel FMD virus of Taiwan and it presented various levels of susceptibility in cattle species.  相似文献   

20.
It has been recommended that meat-and-bone meal (MBM) be incinerated at 850 °C for at least 2 s and the ashes and slag disposed of in controlled landfills, to dispose of animal-derived proteins. Most commonly, the MBM is incinerated in cement works or coal-fired power plants and the ashes and slag are incorporated into the cement or concrete.

Our goal was to assess with a Monte Carlo simulation model the bovine spongiform encephalopathy (BSE) risk to cattle and humans posed by the ash and slag. The results will be used by decision makers to evaluate the need for disposal of the fly ash in controlled landfills and the feasibility of use of the ash by the phosphate and fertilizer industries.

We assumed that all specified risk material (SRM) and MBM produced in Denmark would be incinerated in this gas-fired power plant. Based on observations in 2001, we assumed that, on average, six (range: 0–15) clinical BSE cases each year were rendered into MBM and incinerated. In addition, SRM or carcasses from 0 to 31 (median = 10) BSE-infected-but-undetected animals/BSE case were also incinerated.

The simulations were run on a 1-week basis. Our results suggest that if the slag is collected and re-incinerated the median BSE infectivity remaining in the fly ash per week would be 3.1E−11 cattle ID50. A cattle ID50 is the amount of infectivity that will cause infection in 50% of cattle exposed to it. During the weeks when BSE was infected in the SRM-MBM, the median infectivity in the fly ash was estimated as 8.7E−10 cattle ID50 and 2.9E−12 human ID50. The 95th percentiles were 2.1E−08 cattle ID50 and 5.8E−10 human ID50, respectively. One ton of fly ash would contain ≤1.8E−07 cattle ID50 95% of the time. These are the potential exposures of the cattle or human populations. The potential exposures of individuals are far less.  相似文献   


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