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This study examines the effectiveness of two methods for cryopreserving post-mortem epididymal sperm - conventional slow freezing employing a short equilibration time with glycerol, and ultra-rapid freezing - from the wild ruminant species Ovis musimon (mouflon) and Dama dama (fallow deer). A Tris-citric acid-glucose (TCG) + 12% egg yolk-based medium was used for the conventional slow freezing of the fallow deer sperm, whereas a Tes-Tris-glucose (TEST) + 6% egg yolk-based medium was used for the mouflon sperm. Glycerol was added to a final concentration of 5% to both media. The same diluents were used for ultra-rapid freezing but replacing the glycerol with 100 mM of sucrose. Sperm variables (motility, viability, acrosome integrity, membrane integrity, and morphological abnormalities) were analyzed before and after cryopreservation. Although values were generally better after the thawing of the conventionally cryopreserved sperm, total sperm motility (38.40 ± 4.44% in mouflon and 31.25 ± 3.37% in fallow deer) and total live sperm (47.19 ± 5.18% in mouflon and 43.13 ± 2.43% in fallow deer) were acceptable for the ultra-rapidly cooled sperm. Independent of the cryopreservation method, membrane integrity, acrosome integrity and the percentages of dead sperm and sperms with a damaged acrosome were better for the cryopreserved mouflon sperm than the fallow deer sperm (P < 0.05). Despite exerting a more harmful effect on sperm variables than conventional freezing, ultra-rapid freezing may be a useful alternative for the cryopreservation of these species' epididymal sperm in the field, as this simple technique does not require sophisticated equipment and expertise. [ABSTRACT FROM AUTHOR]

Abstract: Mouflon and domestic Manchega sheep differ in the timing of their reproductive season under natural photoperiod (NP) conditions. This study examines whether they also differ in their reproductive responses to artificial photoperiod cues. For this, mouflons (n =24) and ewes (n =24) were exposed between the winter and summer solstices to artificial long days (LD: 16h light/day), to short days (SD) simulated via the use of melatonin implants, or to NP conditions (controls), and their ovulatory activity monitored. The effects of these treatments on annual changes in prolactin concentration were also recorded. In the LD mouflon ewes, the offset and onset (7 March±5 and 2 October±4, respectively) of cyclic ovulatory activity occurred earlier (P <0.001) than in the NP animals (26 April±6 and 20 October±2, respectively), but no differences were seen (P >0.05) between the SD and NP mouflon ewes in either the onset of anoestrus (12 May±6 and 26 April±6, respectively) or the onset of subsequent ovulatory activity (13 October±8 and 20 October±2, respectively); however the duration of the anoestrus period was significantly reduced in the SD. In LD Manchega ewes, the onset of anoestrus was advanced (2 February±5 vs 15 March±11), but ovulatory activity started at the same time as in NP Manchega ewes (16 July±4 vs 5 July±8). In the SD Manchega ewes, two animals showed continuous cyclic ovulatory activity over the course of the experiment while the remainder entered anoestrus two months later (16 May±6, P <0.001) than their NP counterparts. In these SD ewes, the onset of cyclic ovarian activity was very variable. An annual rhythm of plasma prolactin concentration was seen in both the mouflon and Manchega ewes under all three photoperiod conditions. However, the amplitudes of the changes seen in prolactin concentration were smaller in both the LD and SD animals than in the corresponding NP animals (P <0.001). In conclusion, the results show that these two types of Mediterranean sheep differ in their ovulatory response when subjected to artificial photoperiods. The results also suggest that refractoriness to SDs may be the most important physiological mechanism regulating the onset of anoestrus in highly seasonal breeds, but not in less seasonal breeds. [Copyright &y& Elsevier]

Abstract: This study examines the patterns of melatonin secretion during postnatal development in wild (mouflon; n =7) and domestic (Spanish Merino; n =6) female lambs under their natural photoperiod conditions. The aim was to determine whether these types of sheep which differ in the timing of puberty, also differ in the establishment of daily melatonin secretory rhythms and/or in the nocturnal plasma melatonin secretion. In addition, the time when the lambs first reached nocturnal levels of melatonin similar to adults was also evaluated. For this purpose, the melatonin secretion in lambs was compared with those of their mothers. A day/night (D/N) difference in plasma melatonin concentration was noticed as early as 1 day after birth in the Merino female lambs (D: 5.9±1.0pg/ml compared to N: 22.0±3.3pg/ml; p <0.05), and by 1 week after birth in the mouflon female lambs (D: 4.9±0.3pg/ml compared to N: 56.9±15.3pg/ml; p <0.05). An effect of the genotype (p <0.05) and age (p <0.01) was detected on mean nocturnal plasma melatonin concentrations, which were lower in the Merino than in the mouflon lambs. Night-time plasma concentration of melatonin was also high in mouflon than in Merino mothers (p <0.05). No differences were detected between the wild genotype and the domestic one in the time when the lambs first reached nocturnal levels of melatonin similar to those of their mothers. [Copyright &y& Elsevier]

Abstract: An interspecific embryo transfer program was conducted for genetic improvement and increasing the number of offspring from a flock of mouflon sheep in Argentina. The female donor mouflons were divided into three groups, G1 (n =5), G2 (n =4) and G3 (n =5). The total NIH-FSH-P1 dose given to each donor on the superovulatory treatment was 260, 200 and 160mg for G1, G2 and G3, respectively. The mouflons in G3 were maidens, while the others were multiparous. Domestic Corriedale ewes (n =60) were synchronized and used as recipients. The embryo recovery and transfer was performed by a surgical method. Mouflons (n =13) responded to the superovulatory treatment with an average of 9.1±2.8 ovulations. A low incidence of early luteal regression was found (1 out of 14 donors). Embryo recovery rates were 60, 31 and 76% in groups G1, G2 and G3, respectively. The percentage of transferable embryos obtained in G1 and in G2 exceeded 80%. None of the embryos obtained from G3 were of transferable quality. In G1, 25 transferable embryos were recovered and transferred to 13 recipients, resulting in a pregnancy rate of 76.9% (10/13). In G2, 10 embryos were transferred to 5 recipients, resulting in a 60% pregnancy rate (3/5). Lambing rate was 60% (15/25) and 30% (3/10) for G1 and G2, respectively. Thirteen lambs were born to the 14 donors following natural service after the embryo recoveries. This study demonstrates that the application of IET technology would have great reproductive impact, especially when the donor mouflon hinds are selected according to age and reproductive history. [Copyright &y& Elsevier]

Annual variations in the growth of horns, and their correlation with seasonal changes of testicular size, and prolactin (PRL) and melatonin secretion were monitored in six pubertal mouflon rams living in their original latitude (40°N). Mouflons born and maintained under captive conditions were classified in two age classes: sub-adult (2 years; n = 3) and adult (≥3 years; n = 3). The rate of horn growth was greater (P < 0.001) in sub-adult than in adult mouflon rams. Horn growth was influenced by season in both adult and sub-adult mouflons (P < 0.05) with largest monthly growth occurring in spring and summer. Seasonal variations of plasma PRL concentrations were correlated with horn growth in adult, but not in sub-adult mouflon rams. The rate of horn growth was inversely correlated with testicular size (r = -0.5, P = 0.07). Seasonal changes in the amplitude of the daily melatonin rhythm in solstices and equinoxes were observed, which were not correlated with variations in the rate of horn growth. These results provide support for a possible role of PRL in the control of growth of horns in the adult mouflon. [Copyright &y& Elsevier]

This study compares the effectiveness of two methods of sperm selection - Capripure(®) density-gradient centrifugation (DGC) and dextran swim-up (DSU) - in semen samples from Iberian ibex (Capra pyrenaica) and European mouflon (Ovis musimon). During the increasing photoperiod, Capripure(®) DGC improved the percentage of sperm with progressive motility (P<0.05) in ibexes, and selected 60.6% of the initial total number of spermatozoa contained in the ejaculate samples. In mouflon, Capripure(®) DGC selection was unaffected by photoperiod, had no influence on any sperm variable, and selected 47.8% of the initial total number of mouflon spermatozoa in ejaculate samples. Photoperiod had no influence on the effectiveness of DSU in either ibexes or mouflons. In the ibexes, DSU reduced (P<0.05) the percentage of sperm cells with morphological abnormalities, but only selected 11.3% of the initial total number of spermatozoa in ejaculate samples. In the mouflons, DSU had no significant influence on any sperm variable, and selected 27.8% of the initial total number. Capripure(®) DGC improved ibex and mouflon sperm motility (P<0.05) following 30min and 2h of post-centrifugation, stress-inducing incubation, respectively. In both ibexes and mouflon, sperm cells showing non-progressive motility were found after only 20 h of post-centrifugation incubation following Capripure(®) DGC selection. In conclusion, Capripure(®) DGC would seem a useful method for selecting the best spermatozoa from both ibex and mouflon ejaculates., (Copyright © 2014 Elsevier B.V. All rights reserved.)