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 />
126 Poster Abstracts<br />
be due to <strong>in</strong>trauter<strong>in</strong>e <strong>in</strong>sem<strong>in</strong>ations at two different po<strong>in</strong>ts. In the<br />
future studies, it is suggested that, non-surgical <strong>in</strong>trauter<strong>in</strong>e<br />
<strong>in</strong>sem<strong>in</strong>ation techniques are nee<strong>de</strong>d to be tried <strong>in</strong> queens.<br />
P297<br />
Assessment of reproductive histology and sex steroid<br />
receptor expression <strong>in</strong> the domestic cat (Felis catus)<br />
follow<strong>in</strong>g chronic exposure to phytoestrogens<br />
Bell, K 1 *, Ugarte, CE 1 , Tucker, LA 2 , Roe, WD 3 , Thomas, DG 1<br />
1Institute of Food Nutrition and Human Health, Massey University, New<br />
Zealand; 2 Waiti Hill, New Zealand; 3 Institute of Veter<strong>in</strong>ary Animal Biomedical<br />
Sciences, Massey University, New Zealand<br />
Phytoestrogens are secondary plant compounds, <strong>in</strong>corporated <strong>in</strong>to<br />
commercially prepared felid diets through the use of soy-<strong>de</strong>rived<br />
<strong>in</strong>gredients. The phytoestrogens geniste<strong>in</strong> and daidze<strong>in</strong>, have been<br />
shown to elicit changes <strong>in</strong> reproductive tract histology and sex steroid<br />
receptor expression <strong>in</strong> a variety of mammalian species. These<br />
phytoestrogens are consi<strong>de</strong>red to be potential aetiological agents <strong>in</strong><br />
the <strong>in</strong>fertility suffered by a large percentage of the captive cheetah<br />
(Ac<strong>in</strong>onyx jubatus) population. To <strong>in</strong>vestigate this hypothetical role <strong>in</strong><br />
felid reproduction, domestic cats (n = 6; 4 female, 2 male) were<br />
exposed to dietary geniste<strong>in</strong> and daidze<strong>in</strong> (300µg/g DM total<br />
isoflavones) from wean<strong>in</strong>g (8 weeks of age) until approximately 15<br />
months of age. A control group of related cats (n = 10, 8 female, 2<br />
male) were reared un<strong>de</strong>r i<strong>de</strong>ntical conditions and fed the same diet<br />
without the addition of phytoestrogens. Reproductive tracts were<br />
collected from all animals dur<strong>in</strong>g rout<strong>in</strong>e gona<strong>de</strong>ctomy and processed<br />
for histological and immunohistochemical analysis (IHC). Tissues<br />
were collected from female animals (mean age 485 days) dur<strong>in</strong>g <strong>in</strong>teroestrous<br />
as assessed by vag<strong>in</strong>al cytology, and from male animals at<br />
350 days of age. Reproductive tracts were assessed for<br />
histopathological changes, and other parameters <strong>in</strong>clud<strong>in</strong>g uter<strong>in</strong>e<br />
lum<strong>in</strong>al epithelial cell height and follicular <strong>de</strong>velopment <strong>in</strong> females.<br />
The expression and distribution of Estrogen Receptor (ER)-α, ERβ<br />
and Progesterone Receptor (PR) was assessed <strong>in</strong> ovarian and uter<strong>in</strong>e<br />
tissue us<strong>in</strong>g IHC techniques. Wet weight of the reproductive tracts did<br />
not differ between groups and all but one tract (treatment group) were<br />
with<strong>in</strong> normal expected range of <strong>in</strong>flammatory cell <strong>in</strong>filtration.<br />
Lum<strong>in</strong>al epithelial cell height was greater <strong>in</strong> treatment animals<br />
(5.39µm vs. 4.36µm; p < 0.05) but no differences were <strong>de</strong>tectable <strong>in</strong><br />
ovarian histology. Expression of ERα and ERβ was up-regulated <strong>in</strong><br />
the tracts of treatment animals, whilst PR expression was generally<br />
down-regulated, compared to controls (p < 0.05). Tissue- and<br />
receptor-specific variation was apparent. Although isoflavones were<br />
not found to be uterotrophic, the observed histological changes were<br />
suggestive of oestrogenic activity. Furthermore, the ability of<br />
isoflavones to modulate the proportional expression of sex steroid<br />
receptors may have implications for fertility and fecundity <strong>in</strong> later life.<br />
Future <strong>in</strong>vestigations <strong>in</strong> domestic cats utilis<strong>in</strong>g larger sample sizes,<br />
regimes <strong>in</strong>clud<strong>in</strong>g <strong>in</strong> utero and/or lactational exposure and controlled<br />
fertility and fecundity test<strong>in</strong>g are warranted.<br />
P298<br />
The effect of GnRH on fertility of alpacas <strong>in</strong>sem<strong>in</strong>ated<br />
with frozen-thawed semen<br />
Bravo, W 1 *, Ramos, A 2 , Alarcon, V 3 , Ordoñez, C 2<br />
1Camelid Veter<strong>in</strong>ary Services, United States; 2 Centro Experimental La Raya,<br />
Universidad Nacional San Antonio Abad, Cusco, Peru; 3 <strong>Facultad</strong> <strong>de</strong><br />
Agronomia y Zootecnia, Universidad Nacional San Antonio Abad, Cusco,<br />
Peru<br />
between the three groups, with 72.6% of females ovulat<strong>in</strong>g. There<br />
was no significant difference <strong>in</strong> pregnancy at 21 days between the two<br />
dosages of GnRH, with 75%, and 76.2% of females be<strong>in</strong>g pregnant<br />
for 0.1 μg and 1.0 μg GnRH, respectively; however, 65% of females<br />
of the control group were pronounced pregnant, which is significantly<br />
different than the females that received GnRH (P 0.05). Lower<br />
ERα and PR scores (P < 0.05) and higher numbers of leukocytes (P <<br />
0.05) were observed <strong>in</strong> the pyometra groups than the normal bitches.<br />
Differences of the ERα and PR scores were not seen between the<br />
open- and closed-cervix pyometra (P > 0.05) whereas higher number<br />
of neutrophils was found <strong>in</strong> the open-cervix than closed-cervix<br />
pyometra (P < 0.05).<br />
Conclusions The ERα and PR expressions <strong>in</strong> the cervix of dogs are<br />
<strong>in</strong>fluenced by stages of the oestrus cycle. Neutrophils <strong>in</strong>filtration <strong>in</strong><br />
the cervical tissue appears to <strong>in</strong>volve <strong>in</strong> cervical dilatation <strong>in</strong><br />
pyometra bitches.<br />
Gonadotrop<strong>in</strong> releas<strong>in</strong>g factor (GnRH) was used immediately after<br />
artificial <strong>in</strong>sem<strong>in</strong>ation with frozen-thawed semen <strong>in</strong> alpacas. GnRH<br />
diluted <strong>in</strong> Tris buffer was <strong>de</strong>posited <strong>in</strong> the uter<strong>in</strong>e horn ipsilateral to<br />
the ovary conta<strong>in</strong><strong>in</strong>g an ovulatory-sized follicle. Ovulation was<br />
<strong>in</strong>duced with hCG (Chorulon, Intervet) 24 hours before artificial<br />
<strong>in</strong>sem<strong>in</strong>ation <strong>in</strong> 157 adult female alpacas that were divi<strong>de</strong>d <strong>in</strong>to three<br />
groups: 58 control, 43 with 0.1 μg GnRH, and 56 with 1 μg of GnRH<br />
(Fertagyl, Intervet). There was no difference <strong>in</strong> ovulation percentage