Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
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16 t h International Congress on Animal <strong>Reproduction</strong><br />
84 Poster Abstracts<br />
P169<br />
Early sonographic diagnosis of embryo/fetal compromise<br />
<strong>in</strong> sheep cloned <strong>de</strong>rived pregnancies us<strong>in</strong>g heart rate,<br />
crown rump length and abdom<strong>in</strong>al circumference<br />
measurements<br />
Panarace, M*; Suarez, G; Cané, L; Garnil, C; Med<strong>in</strong>a, M<br />
GOYAIKE S.A.A.C.I. y F., Biotechnology Area, Carmen <strong>de</strong> Areco CC37, CP<br />
6725, Buenos Aires, Argent<strong>in</strong>a<br />
Introduction Sheep clon<strong>in</strong>g has been associated with an <strong>in</strong>creased<br />
<strong>in</strong>ci<strong>de</strong>nce of abnormal <strong>de</strong>velopment of the conceptus and a high rate<br />
of pregnancy and neonatal loss. The overall efficiency rema<strong>in</strong>s low<br />
and the production of live offspr<strong>in</strong>g is still an unpredictable event.<br />
Thus, early prediction of the outcome of pregnancies <strong>in</strong>itiated from<br />
cloned embryos has became an important issue, both for reutilization<br />
of recipients and also to prevent potential harm to the recipient, the<br />
lamb or both. Ultrasonography has proven to be an important, non<strong>in</strong>vasive<br />
method of screen<strong>in</strong>g that can be used as predictor of<br />
embryo/fetal loss.<br />
Objective The aim of this study was to <strong>de</strong>term<strong>in</strong>e if and which of the<br />
<strong>in</strong> vivo ultrasound and Doppler observations of fetal and placental<br />
<strong>de</strong>velopment could be of predictive value for diagnosis of high-risk<br />
pregnancies.<br />
Materials and methods Forty-five natural-mated <strong>de</strong>rived s<strong>in</strong>gleton<br />
pregnancies were used as the control group (A). In addition, 113<br />
Mer<strong>in</strong>o breed recipients bear<strong>in</strong>g clones were split <strong>in</strong>to three groups<br />
accord<strong>in</strong>g to the outcome of their pregnancies: (B) clones that died<br />
between 31 and 90 days (n = 78), (C) clones that died between 91<br />
days and 48 hours after birth (n = 33) and (D) clones alive with more<br />
than six months old (n = 2). Measurements were taken every two<br />
weeks by ultrasonography (Toshiba Nemio 20, Tokyo, Japan) us<strong>in</strong>g<br />
two different convex probes, a 5-10 MHz from days 31 to 60 of<br />
gestation (transrectal) and a 3-6 MHz thereafter (transabdom<strong>in</strong>al).<br />
Three parameters were measured: heart rate (HR, bpm) was<br />
<strong>de</strong>term<strong>in</strong>ed by Doppler <strong>in</strong>terrogation of umbilical arteries; crown<br />
rump length (CRL, mm) was measured <strong>in</strong> a longitud<strong>in</strong>al section of the<br />
embryo and abdom<strong>in</strong>al circumference (ABC, mm 2 ) was registered <strong>in</strong> a<br />
cross section of the fetus abdomen. Data were analyzed by Chi-square<br />
test and differences were consi<strong>de</strong>red significant when P < 0.05.<br />
Results While fetal losses were relatively rare <strong>in</strong> ewes carry<strong>in</strong>g<br />
naturally mated ewes, losses were consi<strong>de</strong>rable <strong>in</strong> the cloned fetuses<br />
(4% versus 97%, respectively). At 31 days of pregnancy 32% of<br />
embryos that died before 90 days (B) and 21% of those that died after<br />
90 days (C) had a HR < 188 bpm; the <strong>in</strong>ci<strong>de</strong>nce of this abnormality<br />
was higher (P < 0.05) <strong>in</strong> (B) and (C) than <strong>in</strong> (A) (0%). Also at 31<br />
days, CRL < 16.5 mm was found <strong>in</strong> 14% of embryos <strong>in</strong> (B) be<strong>in</strong>g<br />
different (P < 0.05) to that observed <strong>in</strong> (A) and (C), (0%). At 87 days<br />
of gestation, 38% of the fetuses <strong>in</strong> (C) had ABC values > 228 mm 2 ,<br />
this <strong>in</strong>ci<strong>de</strong>nce was higher (P < 0.05) than that <strong>in</strong> (A), (0%). Given<br />
these f<strong>in</strong>d<strong>in</strong>gs, it is entirely plausible that the early losses recor<strong>de</strong>d <strong>in</strong><br />
our current study resulted partly from <strong>de</strong>velopmental <strong>de</strong>fects of the<br />
embryo/fetus proper and partly from placental failures (most of the<br />
fetuses with enlarged ABC were simultaneously found with hydrops).<br />
Conclusion A HR < 188 bpm or a CRL < 16.5 mm <strong>de</strong>tected with<br />
ultrasonography at 31 days of pregnancy were important markers for<br />
clones that died between 30 and 90 days of gestation. In addition,<br />
ABC at 87 days was a predictor of fetuses that <strong>de</strong>veloped large<br />
offspr<strong>in</strong>g syndrome.<br />
P170<br />
Hyperglycaemia <strong>in</strong> day 9 of the estrous cycle did not<br />
<strong>in</strong>crease ovulation rate <strong>in</strong> ewes but modified plasma IGF-I<br />
concentrations<br />
Pérez-Clariget, R 1 *; López-Mazz, C 1 ; Regueiro, M 1 ; Crooker, BA 2 ; Carriquiry, M 1<br />
1Department of Animal Production and Pastures, School of Agronomy,<br />
UDELAR, Uruguay; 2 Department of Animal Sciences, University of<br />
M<strong>in</strong>nesota, USA<br />
To evaluate the effect on ovulation rate of <strong>in</strong>creased glycaemia dur<strong>in</strong>g<br />
24 h <strong>in</strong> the luteal phase of cycl<strong>in</strong>g ewes, thirty-four non-lactat<strong>in</strong>g adult<br />
Corriedale ewes (44.6±4.5 kg of body weight and 3.2±0.5 body<br />
condition, <strong>in</strong> a scale 1-5) that grazed native pastures were used. Estrus<br />
was synchronized with 2 doses of cloprostenol 8 d apart and on day 9<br />
of the synchronized estrous cycle, ewes were randomly assigned to<br />
receive an oral adm<strong>in</strong>istration of a neoglucogenic solution (125 ml;<br />
70% glycerol, 20% propilenglycol, 10% distilled water; n=17;<br />
Group-G) or sal<strong>in</strong>e (n=17; Group-S), adm<strong>in</strong>istrated every 6 h for a<br />
24 h-period. All ewes were <strong>in</strong>sem<strong>in</strong>ated with fresh semen at the<br />
follow<strong>in</strong>g (natural) estrus and number of corpus luteum (CL) was<br />
observed by laparoscopy at day 8 of the natural estrous cycle. Means<br />
were consi<strong>de</strong>red to differ when P