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 />
Poster Abstracts 89<br />
LP ewes (1.2 ± 0.3; P < 0.05), but this was not associated with<br />
differences <strong>in</strong> numbers of atretic or healthy follicles, follicular<br />
dynamics or metabolic hormone concentrations. Supplemented ewes<br />
had 2.3 ± 0.6 and 2.2 ± 0.6 healthy follicles on Days 3 and 7, less than<br />
control ewes on Day 3 (4.6 ± 0.6; P < 0.01) but the same as controls<br />
on Day 7 (2.0 ± 0.6). The largest healthy follicle from supplemented<br />
ewes was larger (6.1 ± 0.2 mm) with more granulosa cells (3.7 ± 0.2<br />
million) than <strong>in</strong> non-supplemented ewes (5.4 ± 0.2 mm and 3.0 ± 0.2<br />
million; P < 0.05). Insul<strong>in</strong>, lept<strong>in</strong> and IGF-I concentrations were<br />
higher <strong>in</strong> supplemented than <strong>in</strong> control ewes (P < 0.01). These results<br />
suggest that, while metabolic hormones expla<strong>in</strong> the positive effect of<br />
short-term supplementation on follicular growth, they are not <strong>in</strong>volved<br />
<strong>in</strong> the <strong>in</strong>crease <strong>in</strong> ovulation rate promoted by nutrition dur<strong>in</strong>g<br />
pregnancy. Meat & Livestock Australia and the University of Western<br />
Australia supported this work.<br />
P184<br />
The use of artificial long days is not effective to <strong>in</strong>duce<br />
reproductive activity <strong>in</strong> Mediterranean goat does without<br />
isolation from males<br />
Zarazaga, LA 1 *, Gatica, MC 2 , Guzmán, JL 1 , Celi, I 1<br />
1Universidad <strong>de</strong> Huelva, Carretera <strong>de</strong> Palos <strong>de</strong> la Frontera s/n, 21819, Huelva,<br />
Spa<strong>in</strong>; 2 Universidad Arturo Prat, Avda. Arturo Prat, 2120, Iquique, Chile<br />
One experiment was <strong>de</strong>signed to <strong>in</strong>vestigate whether the treatment<br />
with artificial long days is effective to <strong>in</strong>duce and synchronize<br />
reproductive activity dur<strong>in</strong>g the normal seasonal anoestrous <strong>in</strong><br />
Mediterranean goat does that were not isolated from males. Two<br />
balanced groups of does accord<strong>in</strong>g to their body weight (BW) and<br />
body condition score (BCS) were used. One group was subjected to<br />
artificial long days treatment (16L:8O) (LD, N=24) from 17 th<br />
November to 5 th February, and the control group was ma<strong>in</strong>ta<strong>in</strong>ed<br />
un<strong>de</strong>r natural photoperiod (C, N=23). From November to May BW<br />
and BCS were measured weekly. Oestrous activity was tested daily<br />
us<strong>in</strong>g entire aproned males from the end of the photoperiodic<br />
treatment to the end of the experimental period. Ovulation rate was<br />
evaluated by laparoscopy 7 days after positive i<strong>de</strong>ntification of<br />
oestrous. Effect of LD treatment and month on BW, BCS, was tested.<br />
The effect of treatment was studied on the date of the first <strong>de</strong>tected<br />
oestrous after the end of LD treatment dur<strong>in</strong>g the normal seasonal<br />
anoestrous, on the ovulation rate of the first <strong>de</strong>tected oestrous and on<br />
the percentage of females that showed oestrous. No effect of LD<br />
treatment, month or <strong>in</strong>teraction between both variables on BW was<br />
observed. However, BCS was <strong>in</strong>fluenced by all analyzed factors (at<br />
least P