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1.
The major assumption of this study is that polymorphism of a gene could be used to investigate its allele-specific expression as well as its methylation and imprinting status. Therefore, the aim of this study was to analyze the polymorphism of the coding region of the bovine IGF2 gene and to determine the sequence of its gene exon 6 in Bos taurus and Bos indicus cattle. A single nucleotide “C” deletion/insertion polymorphism was found in both cattle subspecies and a G/T transversion (RFLP-MboII) in the Bos indicus IGF2 gene. A 407-bp fragment of bovine IGF2 exon 6 was sequenced and the sequences (including variable nucleotides) were deposited in the GenBank database. A comparative analysis was performed for this fragment from different species; 99.5% identity was found between Bos taurus and Bos indicus cattle.  相似文献   

2.
The present study aims to understand the existing genetic diversity and structure of six native cattle breeds (Rathi, Tharparkar, Nagori, Mewati, Gir, and Kankrej) adapted to the north-western arid and semi-arid region of India based on microsatellite loci. Various diversity estimates, mean number of alleles (12.84); effective number of alleles (5.02); gene diversity (0.769), and observed heterozygosity (0.667) reflected the existence of substantial within-breed diversity in all the investigated cattle breeds. Mean estimates of F-statistics: FIT = 0.144 ± 0.023, FIS = 0.071 ± 0.021, and FST = 0.078 ± 0.014 were significantly different from zero (P < 0.05). The interbreed relationships indicated moderate level of breed differentiation between the six cattle breeds with least differentiation between Kankrej-Mewati pair. The phylogeny structuring further supported close grouping of Kankrej and Mewati breeds. Correspondence analysis plotted Rathi, Tharparkar, and Gir individuals into three separate areas of multivariate space; whereas, Kankrej, Mewati, and Nagori cattle showed low breed specific clustering. This reflected the existence of discrete genetic structure for Tharparkar, Rathi, and Gir, the prominent dairy breeds of the region; whereas, admixture was observed for Kankrej, Mewati, and Nagori individuals.  相似文献   

3.
The MspI allelic variation in intron III of the bovine growth hormone (bGH) gene was explored using PCR-RFLP in 750 animals belonging to 17 well-recognized breeds of Indian zebu cattle (Bos indicus) reared in different geographic locations of the country. Restriction digestion analysis of a 329-bp PCR fragment of the bGH intron III region with MspI restriction enzyme revealed two alleles (MspI− and MspI+) and two genotypes (−/− and +/−) across the 17 cattle breeds studied. The allelic frequency varied from 0.67 to 0.94 for MspI (−) and from 0.06 to 0.33 for MspI (+) across the 17 breeds, with a combined average frequency of 0.87 and 0.13, respectively. No animal with +/+ genotype was detected across the samples analyzed. The chi-square test showed that the difference in MspI allelic frequency was not significant (p > 0.05), regardless of the geographic origin, coat color, or utility of the cattle breed. The high MspI (−) allele frequencies obtained for Indian zebu cattle in this study are in sharp contrast to those reported for taurine breeds from northern Europe, Mediterranean countries, and America. Findings of this study further substantiate the hypothesis that the MspI (−) allele has an Indian origin.  相似文献   

4.
The average (+/- standard deviation) estrous cycle length of 28 East African Zebu cows over a 217-d period, was 22.6 +/- 6.5 d with no significant (P>0.05) difference between seasons. Estrus had a mean duration of 7.66 +/- 4.68 h (ranging from 1 to 24 h) followed by ovulation 25.82 +/- 5.25 h after the onset of estrus. A larger number of estruses started during the day (64 vs 36% P<0.001) and they were longer during the dry season (P<0.05). Proestrus and metaestrus had average duration of 3.46 +/- 3.57 and 3.65 +/- 2.87 h, respectively. Of the estruses recorded, 31% had no proestrus and 34% had no metaestrus. More mounting occurred during the day than night (59 vs 41%; P<0.001), and mounting activity had two peaks: 0600 to 0900 h and 1600 to 1900 h. The average number of mounts observed per estrus was 9.2 (ranging from 1 to 58), and the mounts were concentrated at the beginning and end of estrus, irrespective of their duration. Vaginal mucus discharge was detected in 64% of the cows in estrus.  相似文献   

5.
云南黄牛和大额牛的mtDNA多态性研究   总被引:8,自引:0,他引:8  
本文以mtDNA限制性内切酶片段长度多态技术分析云南牛的mtDNA多态性。结果表明云南黄牛有两种类型的mtDNA分子,一种是普通黄牛类型,另一种是瘤牛类型,两者的频率分别为33%和67%。没有发现过渡型和重组型。昆明黑白花奶牛的mtDNA与云南黄牛的相类似。云南黄牛可能具有两种起源,即普通黄牛起源和瘤牛起源。今天的云南黄牛群体是这两种类型的混合。大额牛的限制性类型与瘤牛相同,表明大额牛的起源与瘤牛有密切关系。  相似文献   

6.
The amount of trace elements present in edible bovine tissues is of importance for both animal health and human nutrition. This study presents data on trace element concentrations in semitendinosus and cardiac muscles, livers and kidneys of 60 zebu (Bos indicus) bulls, sampled at Jimma, Ethiopia. From 28 of these bulls, blood samples were also obtained. Deficient levels of copper were found in plasma, livers, kidneys and semitendinosus muscles. Suboptimal selenium concentrations were found in plasma and semitendinosus muscles. Semitendinosus muscles contained high iron concentrations. Trace elements were mainly stored in the liver, except for iron and selenium. Cardiac muscles generally contained higher concentrations of trace elements than semitendinous muscles except for zinc. A strong association was found between liver and kidney concentrations of copper, iron, cobalt and molybdenum. Liver storage was well correlated with storage in semitendinosus muscle for selenium and with cardiac muscle for cobalt and selenium. Plasma concentrations of copper, selenium, cobalt were well related with their respective liver concentrations and for cobalt and selenium, also with cardiac muscle concentrations. The data suggest multiple trace element deficiencies in zebu cattle in South-West Ethiopia, with lowered tissue concentrations as a consequence. Based on the comparison of our data with other literature, trace element concentrations in selected edible tissues of Bos indicus seem quite similar to those in Bos taurus. However, tissue threshold values for deficiency in Bos taurus cattle need to be refined and their applicability for Bos indicus cattle needs to be evaluated.  相似文献   

7.
Sequences from the mitochondrial cytochrome b gene were used to examine patterns of variation within and among populations of the ferruginous pygmy-owl (Glaucidium brasilianum) from both North America (including populations from Mexico) and South America. As currently conceived, G. brasilianum is paraphyletic, with North American and South American clades representing two distinct groups that should be recognized as the distinct species G. ridgwayi and G. brasilianum, respectively. Within the G. ridgwayi clade, populations from Arizona, Sonora, and Sinaloa are genetically distinct and share no mitochondrial haplotypes with populations occurring in Texas and other regions of Mexico. According to nested clade analysis this separation may be the consequence of past fragmentation that predates the origin of the Sonora desert. In addition, gene flow between the Arizona/Sonora/Sinaloa populations and the Texas/other Mexico populations is practically nonexistent, with estimates being approximately one individual every 10 generations. Collectively, these data suggest that the Arizona/Sonora/Sinaloa clade should be recognized as either a distinct subspecies or phylospecies from the group containing populations in Texas and the remainder of Mexico. These data should be used as guidelines for pygmy-owl recovery and conservation, as they meet the recommendations of task 3 of the pygmy-owl recovery plan that lists genetic data as essential information for pygmy-owl management.  相似文献   

8.
The faunal assemblage from the 9th-8th millennium BP site at Sha''ar Hagolan, Israel, is used to study human interaction with wild suids and cattle in a time period just before the appearance of domesticated animals of these species in the Jordan Valley. Our results, based on demographic and osteometric data, indicate that full domestication of both cattle and suids occurred at the site during the 8th millennium. Importantly, domestication was preceded in both taxa by demographic and metric population parameters indicating severe overhunting. The possible role of overhunting in shaping the characteristics of domesticated animals and the social infrastructure to ownership of herds is then explored.  相似文献   

9.
This study assessed the distribution pattern of allelic variants at the prolactin-RsaI locus in 23 Indian native cattle breeds (Bos indicus). PCR-RFLP genotyping of a 156?bp fragment of prolactin (PRL) in exon 3 revealed the predominance of the heterozygous AB genotype (mean frequency 0.58) irrespective of utility type (dairy, dual, draft), geographic region (northern, central, southern), and coat color (red, gray) of the breeds analyzed. The overall frequencies of homozygous AA (0.22) and BB (0.20) genotypes were in a similar range. The PRL (A) and PRL (B) alleles exhibited similar gene frequencies (means 0.52 and 0.48, respectively). The existing profile of the PRL-RsaI gene locus in a large set of Indian native cattle breeds was different from that of Bos taurus and cattle breeds of other countries, where either the BB genotype and PRL (B) allele or the AA genotype and PRL (A) allele have been reported to be more prevalent.  相似文献   

10.
ABSTRACT. The composition of the fauna of rumen ciliates in zebu cattle in Kenya was surveyed and 13 genera containing 51 species with 19 formae were identified. Four new species were recognized, then described as Diplodinium africanum n. sp., Diplodinium nanum n. sp., Eudiplodinium kenyensis n. sp., and Ostracodinium iwawoi n. sp. In addition, Buetschlia triciliata and Ostracodinium stokyi were found for the second and third times and described as Hsiungia triciliata n. comb. and Enoploplastron stokyi n. stat., with two formae, respectively. The species composition was similar to that of Indian zebu but several species were considered to originate from African native ruminants. In the percentage composition of genera, the numbers of Entodinium, which normally predominate in rumens in other areas, were very low.  相似文献   

11.
12.
Summary A and B cells in the pancreatic islets of cattle are interlaced with one another. The histochemical characteristics of the islet cells is similar to that of some other mammals. Series of differences are however detected concerning: the positive reaction for glucose-6-phosphatase in the A cells and in the epithelium of the excretory ducts, the simultaneous presence of alkaline phosphatase in the A and B cells, a higher contents of phospholipids in the B cells and a lack of histochemically provable zinc. These differences in the histochemistry of the pancreatic islets of cattle are in authors, opinion an expression of peculiarity of the species.  相似文献   

13.
Leng J  Xie L  Zhu R  Yang S  Gou X  Li S  Mao H 《Molecular biology reports》2011,38(8):4863-4872
The dominant rumen bacteria in Gayals, Yaks and Yunnan Yellow Cattle were investigated using PCR-DGGE approach. The analysis of DGGE profiles, identification of dominant bands and phylogenetic analysis 16S rDNA sequences in DGGE profiles were combined to reveal the dominant bacterial communities and compared the differences between those cattle species. DGGE profiles revealed that Gayals had the most abundant dominant bacteria and the lowest similarity of intraspecies between individuals than other two cattle species. A total of 45 sequences were examined and sequence similarity analysis revealed that Gayals had the most sequences appeared to uncultured bacteria, accounting for 85.0% of the total sequences, Yaks and Yunnan Yellow Cattle had 44.4 and 68.8% uncultured bacterial sequences, respectively. According to phylogenetic analysis, the rumen dominant bacteria of Gayals were mainly phylogenetically placed within phyla firmicutes and bacteroidetes, and the known bacteria were mainly belonged to the genera Lachnospiraceae bacterium, Ruminococcus flavefaciens and Clostridium celerecrescens. Moreover, the dominant bacteria of Yaks were also mainly belonged to phyla firmicutes and bacteroidetes, and the known dominant bacteria were including Ruminococcus flavefaciens, Butyrivibrio fibrisolvens, Pseudobutyrivibrio ruminis, Schwartzia succinivorans and Clostridiales bacterium, most of them are common rumen bacteria. In addition, the dominant bacteria in Yunnan Yellow Cattle were belonged to phyla firmicutes, bacteroidetes and Actinobacteria, and the known dominant bacteria containing Prevotella sp., Staphylococci lentus, Staphylococcus xylosus and Corynebacterium casei. Present study first detected Staphylococcus lentus and Staphylococcus xylosus in the rumen of cattle.  相似文献   

14.
It is now clear that whole genome duplications have occurred in all eukaryotic evolutionary lineages, and that the vast majority of flowering plants have experienced polyploidisation in their evolutionary history. However, study of genome size variation in microalgae lags behind that of higher plants and seaweeds. In this study, we have addressed the question whether microalgal phylogeny is associated with DNA content variation in order to evaluate the evolutionary significance of polyploidy in the model genus Micrasterias. We applied flow-cytometric techniques of DNA quantification to microalgae and mapped the estimated DNA content along the phylogenetic tree. Correlations between DNA content and cell morphometric parameters were also tested using geometric morphometrics. In total, DNA content was successfully determined for 34 strains of the genus Micrasterias. The estimated absolute 2C nuclear DNA amount ranged from 2.1 to 64.7 pg; intraspecific variation being 17.4–30.7 pg in M. truncata and 32.0–64.7 pg in M. rotata. There were significant differences between DNA contents of related species. We found strong correlation between the absolute nuclear DNA content and chromosome numbers and significant positive correlation between the DNA content and both cell size and number of terminal lobes. Moreover, the results showed the importance of cell/life cycle studies for interpretation of DNA content measurements in microalgae.  相似文献   

15.
Preantral follicles are a major source of oocytes, and their utilization as an important tool to store large number of female gametes for future use in reproductive programs has been investigated. The increasing importance of studies in this subject, together with the important role of Zebu cattle in the economy of tropical and subtropical countries as well as their well-known differences from European cattle, led to this research. The present study aims to determine the best size interval for sectioning ovarian tissue to isolate preantral follicles from Zebu cows using a tissue chopper and to evaluate the follicular quality after isolation. Furthermore, it aims to provide information about the Zebu cow preantral follicle population and use this data (as a control) to evaluate the effectiveness of the tested isolation method. Testing eight different tissue sectioning size intervals, it was possible to conclude that the 125-microm-section interval is shown to be better than the intervals of 25, 50, 175 and 200 microm to isolate preantral follicles from Zebu cow ovaries. The 125-microm interval allowed the recovery of 26,050+/-1611 (mean +/- S.E.M.) preantral follicles per one-half ovary, while the number of preantral follicles in situ estimated by evaluation of histological sections was 35,288+/-2342 per one-half ovary. Thus, the mean (+/-S.E.M.) recovery rate (=[number of preantral follicles isolated/number of preantral follicles in situ in the same ovary] x 100) was 74.3+/-4.3%. The morphometrical analysis showed that Bos indicus preantral follicles are similar to B. taurus preantral follicles based on previous reports. In conclusion, this study showed that a simple, mechanical method can be used effectively to isolate a large number of intact preantral follicles from Zebu cow ovaries, with a high recovery rate.  相似文献   

16.
This study aims to assess the genetic diversity and population structure of two major zebu dairy breeds (Tharparkar and Rathi) adapted to the arid region of Rajasthan state of India. Various variability estimates indicate the existence of sufficient within-breed genetic diversity. Mean estimates of F-statistics are significantly different from zero: F IS = 0.112 ± 0.029, F IT = 0.169 ± 0.033, F ST = 0.065 ± 0.017. The overall positive value of F IS (0.112) and an F IT value (0.169) that is more than the F ST (0.065) indicate departure from random mating. The drift-based estimates reflect a moderate yet significant level of breed differentiation between the Tharparkar and Rathi breeds. The evaluation of an exact test, showing that allele frequencies across all the loci differed significantly, supports the population differentiation. This is paralleled by the outcome of neighbor-joining clustering based on allele-sharing distance measures. The allocation of a high percentage of individuals (95.7%) to their population of origin and correspondence analysis further substantiates the existence of a cohesive genetic structure in both the breeds.  相似文献   

17.
基于线粒体12S rRNA基因鉴别混合牛肉及制品的牛种来源   总被引:3,自引:0,他引:3  
陈冬  柏凡  周明亮  张翔宇  吴登俊 《遗传》2008,30(8):1008-1014
线粒体基因组具有种内高度保守性。它的12S rRNA基因同时具有抗腐蚀、耐高温的特点, 而被用于饲料、鲜肉及肉制品的来源追踪和物种成分鉴别等研究。利用牦牛、普通牛、水牛作为研究材料, 在牛线粒体12S rRNA基因通用引物扩增片段区域发现3种特异的酶切位点, 可用于混合鲜牛肉及制品的牛种来源的鉴别。结果显示: 牦牛12S rRNA扩增片段被酶切为203 bp和250 bp, 普通牛为134 bp和318 bp, 水牛为86 bp和367 bp, 通过测序验证了特异性位点和酶切的正确性; 对样品经过不同温度(100℃、120℃、140℃、160℃和180℃)处理均能扩增到目的条带, 但条带从120℃开始变淡。该方法在鲜牛肉及制品的牛种来源鉴别上具有简单、快速、廉价等优点。  相似文献   

18.
Dhami AJ  Sahni KL  Mohan G 《Theriogenology》1992,38(3):565-574
A total of 36 semen ejaculates, six from each of three Holstein-Friesian bulls and three Murrah buffalo bulls, were frozen in tris citric acid-fructose-egg-yolk-glycerol diluent after 1 hour of equilibration to study the effect of various cooling rates (15, 30, 60 and 120 minutes from 10 degrees to 5 degrees C vs a control sample cooled for 120 minutes from 28 degrees to 5 degrees C) and thawing temperatures (40 degrees C 60 seconds , 60 degrees C 15 seconds and 80 degrees C 5 seconds ) on prefreeze and post-thaw sperm motility. Sperm motility differed significantly (P < 0.01) between various cooling rates in both the Holstein-Friesian bull semen and the Murrah buffalo semen at prefreezing, immediately post-thawing, and after 1 hour of post-thaw incubation at 38 degrees C. Post-thaw sperm motility and survival at 38 degrees C were significantly (P<0.01) higher in Holstein-Friesian bulls at 60 degrees C and 80 degrees C than at 40 degrees C (39.79+/-2.46% and 38.15+/-2.18% Vs 35.16+/-2.19%, and 20.22+/-2.14% and 19.05+/-2.05% vs 14.83+/-1.64%, respectively). In Murrah buffalo bulls the recovery percentage and survival rate increased significantly (P<0.01) with the increase in temperature from 40 degrees C to 80 degrees C (41.72+/-2.45%, 47.45+/-2.09% and 51.61+/-2.06%; and 9.22+/-1.47%, 11.79+/-1.63% and 12.27+/-1.53%, respectively). Prefreeze motility did not differ between cattle and buffalo bulls (64.97+/-1.08% Vs 67.11+/-0.89%, respectively) but post-thaw motility was significantly (P<0.01) higher in the buffalo (46.93+/- 1.39% Vs 37.70+/-1.32%). While incubation survival was higher in the cattle (18.04+/-1.16% Vs 10.96+/-0.89%). A fast cooling rate was found to be detrimental for cattle spermatozoa, whereas the post-thaw buffalo sperm motility deteriorated very quickly at 38 degrees C. The influence of species-by-cooling rate interaction was significant (P<0.01) for post-thaw motility and survival rate, but the species-by-thawing or cooling-by-thawing interactions were not significant. These results suggest that a cooling rate of 2 hour either at 10 degrees C or 28 degrees C is essential for cattle semen. However, buffalo semen can be frozen successfully after 30 minutes of cooling at 10 degrees C. A thawing temperature of 60 degrees C yielded a higher sperm motility rate than 40 degrees C. Thus, our findings can be applied under tropical conditions for the successful freezing-thawing of bovine semen provided conception rates are not affected adversely.  相似文献   

19.
Whereas the genetic background of horn growth in cattle has been studied extensively, little is known about the morphological changes in the developing fetal horn bud. In this study we histologically analyzed the development of horn buds of bovine fetuses between ~70 and ~268 days of pregnancy and compared them with biopsies taken from the frontal skin of the same fetuses. In addition we compared the samples from the wild type (horned) fetuses with samples taken from the horn bud region of age-matched genetically hornless (polled) fetuses. In summary, the horn bud with multiple layers of vacuolated keratinocytes is histologically visible early in fetal life already at around day 70 of gestation and can be easily differentiated from the much thinner epidermis of the frontal skin. However, at the gestation day (gd) 212 the epidermis above the horn bud shows a similar morphology to the epidermis of the frontal skin and the outstanding layers of vacuolated keratinocytes have disappeared. Immature hair follicles are seen in the frontal skin at gd 115 whereas hair follicles below the horn bud are not present until gd 155. Interestingly, thick nerve bundles appear in the dermis below the horn bud at gd 115. These nerve fibers grow in size over time and are prominent shortly before birth. Prominent nerve bundles are not present in the frontal skin of wild type or in polled fetuses at any time, indicating that the horn bud is a very sensitive area. The samples from the horn bud region from polled fetuses are histologically equivalent to samples taken from the frontal skin in horned species. This is the first study that presents unique histological data on bovine prenatal horn bud differentiation at different developmental stages which creates knowledge for a better understanding of recent molecular findings.  相似文献   

20.
Oligoisotricha bubali, previously observed twice in water buffalo, was detected in rumen contents of domestic cattle (Bos taurus) in two different areas of Tennessee. Concentrations ranged from <1 to 35% of the total protozoa in unweaned calves and up to 72% in older animals in feedlot. In contrast to the other genera of holotrichs, both total numbers and percent composition of O. bubali increased when animals were fed a corn silage-concentrate diet.  相似文献   

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