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131.
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Embryonic mortality is found to be the main source of reproductive wastage in domestic ruminants. Many genes are involved in the growth and development of the embryo, and the interferon‐stimulated gene 15 (ISG 15) is one of the major gene stimulated by interferon tau, the maternal recognition of pregnancy signal in ruminants. In this study, both genomic and cDNA sequences of ISG 15 from Bos indicus (Deoni breed) were amplified and characterized. The genomic sequence of Deoni ISG 15 exhibited 99% identity with Bos taurus and 97% identity with that of Bos mutus and Bubalus bubalis. Moreover qRT‐PCR analysis revealed constitutive expression of the ISG 15 mRNA in peripheral blood mononuclear cells of Deoni heifers and multiparous cows during early pregnancy. Fourteen Deoni heifers and fifteen multiparous Deoni cows were synchronized for timed AI by CIDR‐Ovsynch protocol, and six animals were kept as cyclic control in each group. Blood samples were collected on days 7, 14, 16, 18, 21, 30 and 45 from the day of AI. Pregnancy was confirmed by plasma progesterone level through ELISA. A significantly higher expression of ISG 15 mRNA was found on day 16 (< .05) and day 18 (< .05) of pregnancy in nulliparous heifers. Although in multiparous Deoni cows ISG 15 expression was greater in pregnant cows, difference was statistically non‐significant. The result of this study indicates that ISG 15 gene expression is upregulated during 16–18 days of pregnancy and could be used as an early pregnancy marker in dairy cows especially in heifers.  相似文献   
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Groundnut rust (Puccinia arachidis Speg.) is an important air borne pathogen, which causes substantial losses in groundnut yield and quality. Although large numbers of accessions were identified as rust resistant in wild, interspecific derivative and cultivated groundnut species, transfer of resistance to well-adapted cultivars is limited due to linkage drag, which worsens yield potential and market acceptance. A F2 mapping population comprising 117 individuals was developed from a cross between the rust resistant parent VG 9514 and rust susceptible parent TAG 24. Rust resistance was governed by single dominant gene in this cross. We identified 11 (out of 160) RAPD primers that exhibited polymorphism between these two parents. Using a modified bulk segregant analysis, primer J7 (5′CCTCTCGACA3′) produced a single coupling phase marker (J71350) and a repulsion phase marker (J71300) linked to rust resistance. Screening of the entire F2 population using primer J7 revealed that the coupling phase marker J71350 was linked with the rust resistance gene at a distance of 18.5 cM. On the other hand, the repulsion phase marker J71300 was completely linked with rust resistance. Additionally, both J71300 (P = 0.00075) and J71350 (P < 0.00001) were significantly associated with the rust resistance. Marker J71300 identified all homozygous rust resistant genotypes in the F2 population and was present in all the eight susceptible genotypes tested for validation. Thus, J71300 should be applicable for marker-assisted selection (MAS) in the groundnut rust resistance breeding programme in India. To the best of our knowledge this is the first report on the identification of RAPD markers linked to rust resistance in groundnut.  相似文献   
135.
Tropical Animal Health and Production - Murrah buffalo heifers (live weight 135?±?17&nbsp;kg) were fed a total mixed ration without supplementation (CON), or supplemented with...  相似文献   
136.
The present study evaluated the effect of supplementation of retinol in the vitrification solution on the viability, apoptosis and development-related gene expression in vitrified buffalo preantral follicles. Preantral follicles isolated from cortical slices of ovaries were randomly assigned into three groups: Group1—Control fresh preantral follicles; Group 2—Vitrification treatment (Vitrification solution 1 (VS1) –TCM-199 + 25 mM HEPES + Foetal bovine serum (FBS) 10%, Ethylene glycol (EG): 10%, Dimethyl sulphoxide (DMSO): 10%, Sucrose-0.3 M for 4 min; VS2- TCM-199 + 25 mM HEPES + FBS10%, EG:25%, DMSO: 25%, Sucrose:0.3 M for 45 s); Group3—vitrification treatment +5 μM of Retinol. Preantral follicles were placed in corresponding vitrification medium and plunged into liquid nitrogen (−196°C). After a week, the follicles were thawed and analysed for follicular viability and gene expression. There was no significant difference in the viability rates among the Group 1(Fresh preantral follicles) (91.46 ± 2.39%), Group 2 (89.59 ± 2.46%) and Group 3 (87.19 ± 4.05%). There was a significantly (p < .05) higher mRNA expression of BCL2L1, GDF-9 and BMP-15 in the vitrification + retinol group compared with the control group. There was a significantly (p < .05) higher expression of Caspase-3 and Annexin-5 in the vitrification group and Vitrification + retinol group compared with control group of follicles. It is concluded that the supplementation of 5 μM of Retinol in Vitrification solution was an efficient vitrification procedure for the vitrification of buffalo preantral follicles.  相似文献   
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