Article

Meiotic competence of prepubertal goat oocytes.

Department de Patologia i de Producció Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
Theriogenology (impact factor: 1.96). 02/1994; 41(4):969-80. pp.969-80
Source: PubMed

ABSTRACT The object of this work was to evaluate in vitro maturation of follicular oocytes from the ovaries of prepubertal goats obtained from the slaughterhouse. To obtain the oocytes, follicles were dissected and classified according to their diameters. In the first experiment, oocytes were matured in vitro with granulosa cells. No significant differences were detected in the percentages of maturation between adult and prepubertal goat oocytes recovered from follicles of 2.5 to 6.0 mm in diameter (81.82 vs 72.47%, respectively). The percentage of maturation increased to 88.0% in prepubertal goat oocytes from 3.0 to 6.0-mm follicles. In the second experiment, the percentage of maturation of prepubertal goat oocytes was greater after 27 than after 24 h. In the third experiment, the maturational capacity of prepubertal goat oocytes according to follicular diameter was evaluated. The percentages of maturation after 27 h of culture with no granulosa cells were 24.14, 56.60 and 74.78%, respectively, for follicles 1.0 to 1.9 mm, 2.0 to 2.9 mm, and 3.0 to 6.0 mm in diameter. As the follicular diameter increased, growth of the oocyte as well as a greater number of oocytes with more cumulus cell layers were observed. A correlation between the diameter of the oocyte and its competence to complete in vitro maturation was also observed. Oocytes with more cumulus cell layers showed only a slight superiority in their capacity for maturation in large-size follicles (3.0 to 6.0 mm), but the difference was not significant. In conclusion, oocytes from prepubertal goats complete their growth and reach meiotic competence in follicles larger than 3.0 mm. With these oocytes it is possible to obtain in vitro maturation results similar to those from adult goats.

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    R B Gilchrist, P L Nayudu, J K Hodges
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    Biology of Reproduction 01/1997; 56(1):238-46. · 4.01 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

6.0-mm follicles
 
adult goats
 
cumulus cell layers
 
diameters
 
first experiment
 
follicles larger
 
follicular diameter
 
follicular oocytes
 
greater number
 
large-size follicles
 
meiotic competence
 
Oocytes
 
prepubertal goat oocytes
 
prepubertal goats
 
prepubertal goats complete
 
second experiment
 
slight superiority
 
third experiment
 
vitro maturation
 
vitro maturation results