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 211<br />
but not all the parameters; the magnitu<strong>de</strong> of the changes <strong>in</strong> the sperm<br />
k<strong>in</strong>ematic parameters was quite similar for each of the 8 bulls between<br />
fresh and post-thaw semen. Immediatly after thaw<strong>in</strong>g, VCL and VAP<br />
showed significant differences among the 8 bulls, however VSL was<br />
no significantly different. Individual variation <strong>in</strong> semen freezability is<br />
recognized to exists <strong>in</strong> bov<strong>in</strong>e, and has been related with the <strong>in</strong>ci<strong>de</strong>nce<br />
of motile dist<strong>in</strong>ct sperm subpopulations <strong>in</strong> the fresh ejaculate, but<br />
further results are nee<strong>de</strong>d to complete the Asturiana <strong>de</strong> la Montaña<br />
genetic resource bank characterization.<br />
This work was performed <strong>in</strong> collaboration with ASEAMO and<br />
supported by RZ2004–00031–C02–01.<br />
P555<br />
Captive breed<strong>in</strong>g strategies affect sperm traits <strong>in</strong><br />
Peromyscus leucopus<br />
Mart<strong>in</strong>ez-Pastor, F 1 *; Malo, AF 2,3 ; Alaks, G 2 ; Lacy, RC 2<br />
1National Wildlife Research Institute (IREC) (UCLM-CSIC-JCCM) and<br />
Institute of Regional Development (IDR), University of Castilla-La Mancha,<br />
Spa<strong>in</strong>; 2 Chicago Zoological Society, Dept. of Conservation Science, 3300<br />
Golf Road, Brookfield, IL 60513, USA; 3 Smithsonian Institution, Center for<br />
Conservation and Evolutionary Genetics, National Zoological Park,<br />
Wash<strong>in</strong>gton D.C. 20008, USA<br />
Captive breed<strong>in</strong>g programs are the only option for many endangered<br />
species. However, it is believed that <strong>in</strong>breed<strong>in</strong>g and genetic adaptation<br />
to captivity may make the <strong>de</strong>scendants from many captive programs<br />
unsuitable for release back <strong>in</strong>to the wild. Male fertility is one of the<br />
traits potentially affected, so there is a need to known how captive<br />
breed<strong>in</strong>g programs affect sperm traits. We have measured the effects<br />
of 10 generations of three different captive breed<strong>in</strong>g strategies on<br />
Peromyscus leucopus, orig<strong>in</strong>at<strong>in</strong>g from the same wild population: (1)<br />
random mat<strong>in</strong>g (RAN), (2) m<strong>in</strong>imiz<strong>in</strong>g the mean k<strong>in</strong>ship (MK) of the<br />
offspr<strong>in</strong>g (Species Survival Plan breed<strong>in</strong>g strategy; SSP) and (3)<br />
select<strong>in</strong>g for docility (DOC), by which more docile mice (behavioral<br />
scores) are bred (mimick<strong>in</strong>g the <strong>de</strong>fault breed<strong>in</strong>g strategy <strong>in</strong><br />
captivity). Twenty males from each group were euthanized (CO 2 ).<br />
Cauda epididymes were collected and put <strong>in</strong> a 0.5-mL drop of<br />
modified Tyro<strong>de</strong> (300 mOsm/kg), covered with paraff<strong>in</strong> oil (37 °C),<br />
and pierced. After 5 m<strong>in</strong>, the medium was transferred to microtubes.<br />
We evaluated the number of spermatozoa (Neubauer hemocytometer),<br />
% of motility (light microscopy ×400) and viability (eos<strong>in</strong>/nigros<strong>in</strong><br />
sta<strong>in</strong><strong>in</strong>g, ×400). Spermatozoa were challenged us<strong>in</strong>g an osmotic<br />
resistance test (ORT): osmolality was raised to 500 mOsm/kg, and<br />
after 5 m<strong>in</strong> reverted to 300 mOsm/kg, assess<strong>in</strong>g motility and viability<br />
5 m<strong>in</strong> later. The effect of the 3 groups on sperm traits was analyzed by<br />
ANOVA and Tukey test (results as median and <strong>in</strong>terquartile range).<br />
RAN yiel<strong>de</strong>d significantly more spermatozoa (146.4×10 6 [113.3,<br />
191.6]) than DOC (100.8×10 6 [80.3, 116.7]), SSP be<strong>in</strong>g <strong>in</strong> between<br />
(138.2×10 6 [85.1, 176.6]). Motility (77.5% [68.8, 85]) and viability<br />
(61% [53.8, 70.6]) were not different between groups. After ORT,<br />
viability <strong>de</strong>creased (48% [38.9, 55]), but the change was not<br />
significantly different among groups. However, motility was<br />
significantly lower for DOC (27.5% [20, 36.3]) than for RAN (40%<br />
[35, 42.5]) or SSP (42.5% [38.8, 55]). Overall, sperm numbers and<br />
motility were reduced <strong>in</strong> the DOC group, announc<strong>in</strong>g the negative<br />
reproductive effects of not m<strong>in</strong>imiz<strong>in</strong>g MK and suggest<strong>in</strong>g the<br />
absence of large differences between RAN and SSP. Our results<br />
suggest that the breed<strong>in</strong>g strategy affects sperm traits, and that<br />
select<strong>in</strong>g the more docile <strong>in</strong>dividuals as bree<strong>de</strong>rs might pose a risk.<br />
However, genetic drift might also be play<strong>in</strong>g a role. Lastly, this study<br />
might help with the setup of sperm banks for the conservation of<br />
endangered species from this genus (e.g., Alabama beach mouse, P.<br />
polionotus ammobates).<br />
P556<br />
Ovarian tissue cryopreservation <strong>in</strong> the doe rabbit: from<br />
freez<strong>in</strong>g to birth<br />
Neto, V*; Joly, T; Salvetti, P; Lefranc, AC; Corrao, N; Guér<strong>in</strong>, P; Buff, S<br />
Université <strong>de</strong> Lyon, Unité Cryobio - ENVL/ISARA Lyon, Ecole Nationale<br />
Vétér<strong>in</strong>aire <strong>de</strong> Lyon, 1 avenue Bourgelat, 69280 Marcy l’Etoile<br />
Introduction Ovarian tissue cryopreservation aims to preserve<br />
simultaneously thousands of immature (primordial to primary stage)<br />
follicles of the ovarian stock. It may allow preservation of the<br />
reproductive potential of women who are at risk of becom<strong>in</strong>g sterile<br />
and may also contribute to preserve the animal genetic resources. The<br />
objectives of this study <strong>in</strong> the doe rabbit were to <strong>de</strong>term<strong>in</strong>e the<br />
<strong>in</strong>fluence of different freez<strong>in</strong>g parameters and to propose a slow<br />
freez<strong>in</strong>g process for the cryopreservation of the ovarian tissue.<br />
Methods A fractional experimental <strong>de</strong>sign was used to discrim<strong>in</strong>ate<br />
5 freez<strong>in</strong>g parameters. The nature (DMSO vs. 1,2-PROH) and the<br />
concentration (1.5M vs. 2M) of the cryoprotectant, the nonpenetrat<strong>in</strong>g<br />
cryoprotectant (sucrose or trehalose), the equilibration process (1 vs.<br />
3 steps) and the post-seed<strong>in</strong>g freez<strong>in</strong>g rate (0.3 vs. 2°C/m<strong>in</strong>) were<br />
evaluated. The morphological analysis of the preantral follicles was<br />
performed before (control) and after freez<strong>in</strong>g. The best comb<strong>in</strong>ation<br />
of freez<strong>in</strong>g parameters was f<strong>in</strong>ally challenged by orthotopic autograft<br />
and <strong>in</strong> vivo resumption of folliculogenesis. Cryopreserved ovarian<br />
fragment was grafted to the controlateral ovarian pedicle of<br />
16 females. Then, females were <strong>in</strong>sem<strong>in</strong>ated along 9 months.<br />
Results The experimental <strong>de</strong>sign showed that 1,2-PROH (p=0.08) and<br />
trehalose (p=0.07) ten<strong>de</strong>d to improve the morphology of preantral<br />
follicles submitted to freez<strong>in</strong>g. The freez<strong>in</strong>g rate seemed to have the<br />
greatest impact on the follicular morphology which was improved by<br />
the use of a freez<strong>in</strong>g rate of 0.3°C/m<strong>in</strong> (p