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Silva M.C.,Federal University of Goais | Lopes F.B.,Federal University of Goais | Vaz C.M.S.,Associacao Brasileira de Criadores de Ovinos Coloridos ABCONC | Paulini F.,University of Brasilia | And 4 more authors.
Small Ruminant Research | Year: 2013

Fifteen morphometric traits and body weight (BW) from 319 adult Crioula Lanada ewes were evaluated. The influence of wool type and geographic location (fixed effects) was tested, in addition to Pearson correlation, factor and discriminatory analysis according to geographic regions and breed ecotypes. Analysis was carried out using the Statistical Analysis System Program. Geographic location revealed significant effect (P< 0.001) on morphometric traits. Most correlations were significant (P< 0.05), thoracic perimeter (TP) with BW (0.72) being the strongest. Correlations between head and body measurements were medium or weak, strongest being between BWs. Multivariate analysis revealed 81% of variance using two factors, where three groups of variables were identified (general body, head and one group including thoracic and BW, respectively). Fine discrimination between herds and also the Fronteira and Serrana ecotypes were observed which opens door to valuable validation of how phenotype relates to genotype and associated SNPs in the Crioula Lanada breed. © 2012. Source

Pontes J.H.F.,In Vitro Brazil Ltda | Melo Sterza F.A.,State University of Mato Grosso do Sul | Basso A.C.,In Vitro Brazil Ltda | Ferreira C.R.,In Vitro Brazil Ltda | And 3 more authors.
Theriogenology | Year: 2011

The objective was to clarify in vitro production of bovine embryos in Brazil. Data from 656 ovum pick-up/in vitro production (OPU/IVP) procedures, performed on 317 Nelore (Bos indicus) donors, without hormone stimulation or control of ovarian follicular waves, were analysed. Donors were subjected to OPU from one to nine times (no specific schedule), with -1.< 15 d between consecutive procedures. There were 20,848 oocytes, of which 15,747 (75.53%) were considered viable, 5,446 embryos were obtained, 5,398 embryos were immediately transferred, resulting in 1,974 pregnancies (36.57%) at Day 30 and 1,788 (33.12%) pregnancies at Day 60. The average number of total and viable oocytes produced per OPU session was (mean -± SEM) 30.84 -± 0.88 and 23.35 -± 0.7 (average of 8.1 -± 0.3 embryos and 3.0 -± 0.1 pregnancies per OPU-IVP procedure). Since oocyte production varied widely among donor, they were designated as very high, high, intermediate, and low, with 58.94 -± 2.04, 32.61 -± 0.50, 22.13 -± 0.50, zand 10.26 -± 0.57 oocytes, respectively, produced by 78, 80, 79, and 80 donors. The number of viable oocytes recovered ranged from 0 to 128; since donors with numerous viable oocytes produced many viable embryos and pregnancies, oocyte production was useful for donor selection. However, there was no significant effect of the number of OPU sessions per donor on mean numbers of oocytes produced. In conclusion, we confirmed field reports of high oocyte production by some Nelore donors and demonstrated individual variation in oocyte yield, which was associated with embryo production and pregnancy rates. © 2011 Elsevier Inc. Source

Barreiros T.R.R.,Laboratorio Of Biotecnologia Da Reproducao Animal | Blaschi W.,Laboratorio Of Biotecnologia Da Reproducao Animal | Santos G.M.G.,Laboratorio Of Reproducao Animal | Morotti F.,Laboratorio Of Reproducao Animal | And 3 more authors.
Theriogenology | Year: 2014

The objective of this study was to investigate the effects of eCG and temporary calf removal (TCR) associated with progesterone (P4) treatment on the dynamics of follicular growth, CL size, and P4 concentrations in cyclic (n = 36) and anestrous (n = 30) Nelore cows. Cyclic (C) and anestrous (A) cows were divided into three groups. The control group received 2 mg of estradiol benzoate via intramuscular (IM) injection and an intravaginal device containing 1.9 g of P4 on Day 0. On Day 8, the device was removed, and the animals received 12.5 mg of dinoprost tromethamine IM. After 24 hours, the animals received 1 mg of estradiol benzoate IM. In the eCG group, cows received the same treatment described for the control group but also received 400 UI of eCG at the time of device removal. In the TCR group, calves were separated from the cows for 56 hours after device removal. Ultrasound exams were performed every 24 hours after device removal until the time of ovulation and 12 days after ovulation to measure the size of the CL. On the same day as the CL measurement, blood was collected to determine the plasma P4 level. Statistical analyses were performed with a significance level of P ≤ 0.05. In cyclic cows, the presence of the CL at the beginning of protocol resulted in a smaller follicle diameter at the time of device removal (7.4 ± 0.3 mm in cows with CL vs. 8.9 ± 0.4 mm in cows without CL; P = 0.03). All cows ovulated within 72 hours after device removal. Anestrous cows treated with eCG or TCR showed follicle diameter at fixed-timed artificial insemination (A-eCG 10.2 ± 0.3 and A-TCR 10.3 ± 0.5 mm) and follicular growth rate (A-eCG 1.5 ± 0.2 and A-TCR 1.3 ± 0.1 mm/day) similar to cyclic cows (C-eCG 11.0 ± 0.6 and C-TCR 12.0 ± 0.5 mm) and (C-eCG 1.4 ± 0.2 and C-TCR 1.6 ± 0.2 mm/day, respectively; P ≤ 0.05). Despite the similarities in CL size, the average P4 concentration was higher in the A-TCR (9.6 ± 1.4 ng/mL) than in the A-control (4.0 ± 1.0 ng/mL) and C-TCR (4.4 ± 1.0 ng/mL) groups (P < 0.05). From these results, we conclude that eCG treatment and TCR improved the fertility of anestrous cows by providing follicular growth rates and size of dominant follicles similar to cyclic cows. Additionally, TCR increases the plasma concentrations of P4 in anestrous cows. © 2014 Elsevier Inc. Source

Ferreira A.R.,Laboratorio Of Reproducao Animal | Ferreira A.R.,University Estadual Of Sao Paulo Julio Of Mesquita Filho | Aguiar Filho L.F.C.,Laboratorio Of Reproducao Animal | Sousa R.V.,Laboratorio Of Reproducao Animal | And 4 more authors.
Genetics and Molecular Research | Year: 2015

Somatic cell nuclear transfer (SCNT) may affect epigenetic mechanisms and alter the expression of genes related to embryo development and X chromosome inactivation (XCI). We characterized allele-specific expression of the X-linked gene monoamine oxidase type A (MAO-A) in the trophectoderm (TF) of embryos produced by SCNT. Total RNA was isolated from individual biopsies (N = 25), and the allele-specificexpression assessed by reverse transcription-polymerase chain reaction-restriction fragment length polymorphism. Both paternal and maternal alleles were expressed in the trophectoderm. However, a higher frequency of the mono-allelic expression of a specific allele was observed (N = 17; 68%), with the remaining samples showing the presence of mRNA from both alleles (N = 8; 32%). Considering that MAO-A is subject to XCI in bovine, our results suggest that SCNT may influence XCI because neither an imprinted (mono-allelic expression in all samples) nor a random (presence of mRNA from both alleles in all samples) pattern of XCI was observed in TF. Due to the importance of XCI in mammalian embryo development and its sensitivity to in vitro conditions, X-linked genes subject to XCI are candidates for use in the development of embryo quality molecular markers for assisted reproduction. © FUNPEC-RP. Source

Pontes J.H.F.,Laboratorio Of Reproducao Animal | Pontes J.H.F.,In Vitro Brazil Ltda | Silva K.C.F.,Laboratorio Of Reproducao Animal | Basso A.C.,In Vitro Brazil Ltda | And 11 more authors.
Theriogenology | Year: 2010

Herein we describe a large-scale commercial program for in vitro production of embryos from dairy Bos taurus, Bos indicus, and indicus-taurus donors, using sexed sperm. From 5,407 OPU, we compared the number of recovered oocytes (n = 90,086), viable oocytes (n = 64,826), and embryos produced in vitro from Gir (Bos indicus, n = 617), Holstein (Bos taurus, n = 180), 1/4 Holstein × 3/4 Gir (n = 44), and 1/2 Holstein-Gir (n = 37) crossbred cows, and the pregnancy rate of recipient cows. Viable oocytes were in vitro matured (24 h at 38.8 °C, 5% CO 2 in air) and fertilized by incubating them for 18 to 20 h with frozen-thawed sexed sperm (X-chromosome bearing) from Gir (n = 8) or Holstein (n = 7) sires (2 × 10 6 sperm/dose). Embryos were cultured in similar conditions of temperature and atmosphere as for IVM, with variable intervals of culture (between Days 2 and 5) completed in a portable incubator. All embryos were transferred fresh, after 24 to 72 h of transportation (up to 2,000 km). On average, 16.7 ± 6.3 oocytes (mean ± SEM) were obtained per OPU procedure and 72.0% were considered viable. Total and viable oocytes per OPU procedure were 17.1 ± 4.5 and 12.1 ± 3.9 for Gir cows, 11.4 ± 3.9 and 8.0 ± 2.7 for Holstein cows, 20.4 ± 5.8 and 16.8 ± 5.0 for 1/4 Holstein × 3/4 Gir, and 31.4 ± 5.6 and 24.3 ± 4.7 for 1/2 Holstein-Gir crossbred females (P < 0.01). The mean number of embryos produced by OPU/IVF and the pregnancy rates were 3.2 (12,243/ 3,778) and 40% for Gir cows, 2.1 (2,426/1,138) and 36% for Holstein cows, 3.9 (1,033/267) and 37% for 1/4 Holstein × 3/4 Gir, and 5.5 (1,222/224), and 37% for 1/2 Holstein-Gir. In conclusion, we compared oocyte yield from two levels of indicus-taurus breeds and demonstrated the efficiency of sexed sperm for in vitro embryo production. Culturing embryos during long distance transportation was successful, with potential for international movement of embryos. © 2010 Elsevier Inc. Source

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