The effect of internal and external factors on bovine embryo transfer results in a tropical environment

Bényei, Balázs; Komlósi, István; Pécsi, Anna; Pollott, Geoffry; Marcos, Cruvinel Heraldo; Campos, Alexandre de Oliveira; Lemes, Maida Paula

doi:10.1016/j.anireprosci.2005.07.012

Cited by 26 publications

(24 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ten sheep breeds included in the study (Table 1) were selected to cover the different sectors of the British sheep industry (see, for example, [17]). The hill breeds (Beulah Speckled Face, Scottish Blackface, North Country Cheviot, Welsh Mountain), which are kept in the harsh hill environment, comprise four of the five most numerous purebreeds and account for 27.5% of ewes kept in GB.…”

Section: Methodsmentioning

confidence: 99%

Associations between lamb survival and prion protein genotype: analysis of data for ten sheep breeds in Great Britain

et al. 2009

View full text Add to dashboard Cite

Background: Selective breeding programmes, based on prion protein (PrP) genotype, have been introduced throughout the European Union to reduce the risk of sheep transmissible spongiform encephalopathies (TSEs). These programmes could have negative consequences on other important traits, such as fitness and production traits, if the PrP gene has pleiotropic effects or is in linkage disequilibrium with genes affecting these traits. This paper presents the results of an investigation into associations between lamb survival and PrP genotype in ten mainstream sheep breeds in Great Britain (GB). In addition, the reasons for lamb deaths were examined in order to identify any associations between these and PrP genotype.

show abstract

Section: Methodsmentioning

confidence: 99%

Associations between lamb survival and prion protein genotype: analysis of data for ten sheep breeds in Great Britain

et al. 2009

View full text Add to dashboard Cite

show abstract

“…First of all, studies depend largely in what is measured as transferrable embryo and consideration such as distance and season (Bastidas and Randel ; Bényei et al. ) management on a farm (Stroud and Hasler ) and embryo grading (Aguilar et al. ) play an important role in establishing the average response.…”

Section: Discussionmentioning

confidence: 99%

“…The differences observed between breeds in relation to embryos production and quality are widely acknowledged (for review, see Barros and Nogueira ), and again many factors such as housing, nutrition and management play an important role in this disparity (Bényei et al. ; Betteridge ). In effect, Hasler () in a review underlines the economical importance of other factors related to ET; for example, in 1978, the cost per dose of the original Armour FSH‐P was $6.50 and the ET practitioner charge for his services $500.…”

Section: Discussionmentioning

confidence: 99%

Is the Production of Embryos in Small‐Scale Farming an Economically Feasible Enterprise?

Sánchez

Lammoglia

Alarcon

et al. 2015

Reprod Domestic Animals

View full text Add to dashboard Cite

The present assay attempts to evaluate the feasibility of using embryo transfer in small community farmers by in vivo study and by modelling the results obtained. From the total of 59 donor cows, 62.7% responded to treatment, with a significant difference (p = 0.002) in the percentage of the response between breeds, being 90.5% (19/21) in Holstein and 47.4% (18/38) in Brahman. A total of 283 embryos were graded as transferable, while 141 as non-transferable, without difference in the percentage of transferable embryo by breed (p = 0.18). The mean of transferable embryos graded as class I and II was not different between Holstein and Brahman (p = 0.96 and p = 0.92, respectively); besides, no differences were observed in the other grades (non-transferable). The highest difference in costs, regardless of its quality by breed, was seen in the lower levels of probable fertility of the embryo transferred, even reaching several hundred dollars. When modelling the expected costs for embryo produced and transferred, values can reach nearly $2000.00 when the probable fertility is only 10%. However, when the probable fertility was 60%, embryo cost was close to $300.00. This technology seems to be viable on average or high-scale systems, having a superovulatory response between 60 and 80% with 4-6 transferrable embryos. Yet, in small-scale farming, due to the reduced number of donors and/or recipients, the costs surpass the economical feasibility of the technique.

show abstract

“…The technical quality assessment relies on the experience, attention to detail and systematic approach of the examiner on analyzing the embryo, from the more evident features as dead and extruded cells, or reduction of the percentage of viable cells to the more subtle characteristics that may influence embryo development such as irregularity of shape, heterogeneity of color, asynchrony between expected and encountered stage of development and the presence of vacuoles. On this classical approach of embryonic morphology, the variables are not measured in an objective form, resulting in low repeatability and subjectiveness of analysis (Bényei et al, 2006; van Loendersloot et al ., 2014; Perkel et al ., 2015; Richardson et al ., 2015; Thompson et al ., 2016). On this approach, a given embryo when analyzed by different examiners may be classified in different distinct degrees of quality (Farin et al ., 1995, 1999; Chen et al ., 2016).…”

Section: Introductionmentioning

confidence: 99%

Methods for assessing the quality of mammalian embryos: How far we are from the gold standard?

Rocha

Passalia

Matos

et al. 2016

JBRA Assisted Reproduction

View full text Add to dashboard Cite

Morphological embryo classification is of great importance for many laboratory techniques, from basic research to the ones applied to assisted reproductive technology. However, the standard classification method for both human and cattle embryos, is based on quality parameters that reflect the overall morphological quality of the embryo in cattle, or the quality of the individual embryonic structures, more relevant in human embryo classification. This assessment method is biased by the subjectivity of the evaluator and even though several guidelines exist to standardize the classification, it is not a method capable of giving reliable and trustworthy results. Latest approaches for the improvement of quality assessment include the use of data from cellular metabolism, a new morphological grading system, development kinetics and cleavage symmetry, embryo cell biopsy followed by pre-implantation genetic diagnosis, zona pellucida birefringence, ion release by the embryo cells and so forth. Nowadays there exists a great need for evaluation methods that are practical and non-invasive while being accurate and objective. A method along these lines would be of great importance to embryo evaluation by embryologists, clinicians and other professionals who work with assisted reproductive technology. Several techniques shows promising results in this sense, one being the use of digital images of the embryo as basis for features extraction and classification by means of artificial intelligence techniques (as genetic algorithms and artificial neural networks). This process has the potential to become an accurate and objective standard for embryo quality assessment.

show abstract

The effect of internal and external factors on bovine embryo transfer results in a tropical environment

Cited by 26 publications

References 31 publications

Associations between lamb survival and prion protein genotype: analysis of data for ten sheep breeds in Great Britain

Associations between lamb survival and prion protein genotype: analysis of data for ten sheep breeds in Great Britain

Is the Production of Embryos in Small‐Scale Farming an Economically Feasible Enterprise?

Methods for assessing the quality of mammalian embryos: How far we are from the gold standard?

Contact Info

Product

Resources

About