Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
Reproduction in Domestic Animals - Facultad de Ciencias Veterinarias
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
16 t h International Congress on Animal <strong>Reproduction</strong><br />
Poster Abstracts 71<br />
of a 14% CP supplement. The lambs were fed with at libitum access<br />
of a 18% PC supplement s<strong>in</strong>ce 15 th days old until 60 th days old. The<br />
data on BW and WW were analyzed by Mixed Mo<strong>de</strong>l procedures of<br />
SAS program. The fixed effects utilized Breed of sire (BS), Breed of<br />
ewe (BE), Sex (Sx), Litter size(L) and season(T) nested <strong>in</strong> BE (T(BE).<br />
The random effects were Sire(S) nested <strong>in</strong> BS and Ewe(E) nested <strong>in</strong><br />
BE. BW and WW were <strong>in</strong>fluenced by BS, L , T(BE) (P 0.05). K lambs<br />
ranked first <strong>in</strong> both measures, 3.42 ± 0.36 kg. and 11.62±1.53 kg. for<br />
BW and WW, respectively. Ile(3.06±0.33) were <strong>in</strong>termediate and<br />
DPN (2.96±0.32), DPB (2.87±0.33), BB(2.74±0.35) and<br />
PB(2.82±0.33) were last for BW. For WW, Ile(9.95. ±1.44), DPN<br />
(9.85±1.40), DPB(9.69±1.44), were <strong>in</strong>termediate and BB(8.77±1.53)<br />
PB(8.45±1.45) were last. S<strong>in</strong>gles lambs (3.69±0.32) had higher<br />
weights than double(2.92±0.32) or multiple litter(2.32±0.34) for BW.<br />
Also S<strong>in</strong>gle lambs (11.21±1.4) were higher than doubles (9.19±1.39)<br />
which were higher than multiples (8.76±1.5). We observed that the<br />
birth weight is affected by Specialized beef Breed of sire used,<br />
without be<strong>in</strong>g a serious risk because they are low. Also the wean<strong>in</strong>g<br />
weight is improved although it is a trait more <strong>in</strong>fluenced by the ewe<br />
performance than sire. Notice that the BB and PB ewes have a small<br />
frame and multiple litters.<br />
Project sponsored by CONACYT-SAGARPA-2004-C01-150<br />
P130<br />
Systemic concentrations of endo- and exogenous FSH <strong>in</strong><br />
anestrous ewes superovulated with Folltrop<strong>in</strong> ® -V after<br />
pretreatment with medroxyprogesterone acetate (MAP)-<br />
releas<strong>in</strong>g vag<strong>in</strong>al sponges and a s<strong>in</strong>gle dose of estradiol<br />
17β (E2 17β)<br />
Bartlewski, PM 1 *; Alexan<strong>de</strong>r, BD 2 ; K<strong>in</strong>g, WA 1<br />
1Department of Biomedical Sciences, Ontario Veter<strong>in</strong>ary College, University<br />
of Guelph, Guelph, Ont., Canada; 2 Department of Farm Animal Production<br />
and Health, Faculty of Veter<strong>in</strong>ary Medic<strong>in</strong>e and Animal Science, University of<br />
Pera<strong>de</strong>niya, Pera<strong>de</strong>niya, Sri Lanka<br />
The synchronization of follicular wave emergence with progest<strong>in</strong> and<br />
estradiol 17β (E 2 17β) prior to superovulation <strong>in</strong> anestrous ewes<br />
reduces the variability <strong>in</strong> ovarian responses by an unknown<br />
mechanism. Follicle stimulat<strong>in</strong>g hormone (FSH) is a primary<br />
promoter of antral follicular growth and maturation, but the relevance<br />
of changes <strong>in</strong> circulat<strong>in</strong>g FSH concentrations to the superovulatory<br />
performance <strong>in</strong> ewes rema<strong>in</strong>s unknown. This report is comprised of<br />
retrospective analyses of serum FSH concentrations <strong>in</strong> anestrous<br />
Ri<strong>de</strong>au Arcott ewes (May-June), which were superovulated with<br />
Folltrop<strong>in</strong> ® -V (porc<strong>in</strong>e FSH), with (n=8; treated ewes) or without<br />
(n=10; control ewes) a 14-day pretreatment with<br />
medroxyprogesterone acetate (MAP)-releas<strong>in</strong>g vag<strong>in</strong>al sponges (60<br />
mg), and a s<strong>in</strong>gle i.m. dose of 350 μg E 2 17β given 6 days after<br />
<strong>in</strong>sertion of sponges. The superovulatory treatment, started 6 days<br />
after E 2 17β <strong>in</strong>jection, consisted of six i.m. doses of Folltrop<strong>in</strong> ® -V (2.5<br />
ml x 1 and 1.25 ml x 5) given twice daily, followed by the bolus<br />
<strong>in</strong>jection of GnRH (50 μg i.m.). In or<strong>de</strong>r to avoid the effects of <strong>in</strong>terbatch<br />
variations <strong>in</strong> pFSH bioactivity, separate batches of Folltrop<strong>in</strong> ® -<br />
V were pooled to prepare sufficient quantities to treat all 18 animals.<br />
Serum samples obta<strong>in</strong>ed dur<strong>in</strong>g the superovulatory treatment were<br />
analyzed by radioimmunoassays (RIA) for concentrations of ov<strong>in</strong>e<br />
(oFSH) and porc<strong>in</strong>e FSH (pFSH), us<strong>in</strong>g species-specific standards and<br />
primary antibodies. Both gonadotrop<strong>in</strong>s have been found to crossreact<br />
with the heterospecific antibody; therefore, cross-reactivity was<br />
subtracted from all FSH concentrations. The control ewes excee<strong>de</strong>d E 2<br />
17β-treated animals <strong>in</strong> serum concentrations of oFSH at 2, 2.5 and 3<br />
days after the first Folltrop<strong>in</strong> ® -V <strong>in</strong>jection (P0.05) between the two groups <strong>in</strong> pFSH concentrations.<br />
The mean ovulation rate and number of recovered embryos did not<br />
differ between the two groups of ewes (P>0.05), but the variability <strong>in</strong><br />
the number of luteal structures and <strong>in</strong> overall embryo yields was lower<br />
<strong>in</strong> E 2 17β-treated ewes (F test; P