INVESTIGADORES
VAZQUEZ Maria Isabel
artículos
Título:
Effects of treatment with a Prostaglandin analogue on developmetal dynamics and functionality of induced corpora lutea in goats
Autor/es:
M.I. VÁZQUEZ; M.S. BLANCH; G.A. ALANIS; M.A. CHAVES; A. GONZALEZ-BULNES
Revista:
ANIMAL REPRODUCTION SCIENCE
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Año: 2010 vol. 118 p. 42 - 47
ISSN:
0378-4320
Resumen:
The aim of this study was to compare morphological and functional
features of spontaneous and induced corpora lutea (CLs) in goats.
Fourteen adult and cycling Anglo Nubian goats (Argentina) were randomly
allocated to two groups: Group N (n = 7) included goats with natural spontaneous oestrus and Group PG (n = 7)
included does in which oestrus was synchronized by the administration
of two i.m. cloprostenol doses, 10 days apart. In both groups, oestrous
behaviour was checked twice daily (Day of oestrus = Day 0) and daily
transrectal ultrasonographies were performed for evaluating CLs and
follicles dynamics through the complete subsequent oestrous cycle; the
luteal activity was determined directly, in terms of progesterone (P4)
secretion, and indirectly, by assessing effects of CL on follicular
dynamics. All goats exhibited oestrous behaviour and ovulation without
differences in ovulation rate (N: 1.67 ± 0.2, PG: 2.0 ± 0.1). The total
luteal tissue area showed linear growth from Day 4 to Day 15 of oestrous
cycle in all goats, but the developmental dynamics differed between
groups, treated goats had larger area (P < 0.01).
Plasma P4 concentrations also increased from Day 0 to Day 15 in all the
does; however, from Day 5 to Day 15, treated does had a lower
concentrations than the untreated group (P < 0.001).
There were differences in the development of follicular waves between
groups; assessment of size-distribution showed that treated group had a
higher number of small and larger follicles (P < 0.05).
The largest follicles recorded in treated goats had a higher maximum
diameter both at the first (PG: 7.6 ± 0.8 mm; N: 4.9 ± 0.7 mm, P < 0.05) and second follicular waves (PG: 6.3 ± 1.4 mm; N: 5.0 ± 0.4 mm, P < 0.05) and a longer growth phase during the second wave (PG: 6.5 ± 1.7 days; N: 4.6 ± 0.7 days, P < 0.05),
coincident with the period of maximal luteal secretion. In conclusion,
synchronization of oestrus and ovulation by the administration of a
prostaglandin analogue causes differences in developmental dynamics and
functionality of induced corpora lutea when compared to natural
spontaneous ovulation.