215 PRODUCTION OF PROGENY WITH SEXED WHITE HANWOO (KOREAN NATIVE ALBINO CATTLE) SEMEN

The aim of the study was to produce sexed progeny of the genetically confined White Hanwoo (albinism). A White Hanwoo bull was selected as the semen donor. The X-bearing sperm were sorted by MoFlo XDP cell sorter from Korea Sexing Biotech (Daegu, South Korea). To compare pregnancy and birth rates as well as semen quality, a Korean proven bull (KPN) was used as control. Total number of nonsorted sperm was 20 × 106 per straw. Double insemination of 2 or 4 × 106 sexed and frozen X-bearing sperm were performed on Hanwoo heifers. The abnormality of nonsorted albino spermatozoa (5 ejaculates) was 24.9 ± 7.31% (but 18.7 ± 6.2% C in KPN 768, derived from 5 straws) with a higher number of distal reflex abnormality in midpiece (11.7% compared with that of KPN 768, 5.6%). There were no differences in pregnancy and birth rates when 2 or 4 × 106 X-bearing sperm were inseminated but nonsorted semen had higher pregnancy rates (P < 0.05). The pregnancy rates of KPN 768, 2 × 106 cells, and 4 × 106 cells X-bearing sperm of White Hanwoo cattle were 85.0% (17/20), 26.3% (5/19), and 50% (7/14), respectively. The birth rates were 80.0% (16/20), 15.8% (3/19), and 21.4% (3/14), respectively. The female offspring rates were 43.8% (7/16), 100% (3/3), and 100% (3/3) (P < 0.05). These results indicated that sex-sorted albino Hanwoo semen could be used for the production of wanted progeny with 2 × 106 cells/straw for AI to heifers.

Influence of gastrointestinal trichostrongylidosis on ram fertility

Influence of gastrointestinal trichostrongylidosis on ram fertility A study on the influence of gastrointestinal trichostrongyles on ram fertility was performed. Two groups of semen donor rams (Sarda breed) were utilized; one was experimentally infected with Haemonchus contortus, Trichostrongylus colubriformis and Teladorsagia circumcincta and the other was used as a control group. In all animals, coprological, haematological and reproductive parameters were studied. The results suggest that the parasites had a limited effect with some changes in phosphorus, cholesterol and chlorine levels. In our experience the parasitic burden produced no significant change on ram fertility.

Testicular function and semen characteristics of Awassi rams treated with melatonin out of the breeding season

The objective of this study was to evaluate the effect of long-term melatonin treatment applied during the non-breeding season on semen characteristics, endocrine function of testicles and baseline level of insulin-like growth factor-I (IGF-I) in Awassi rams kept in the temperate continental zone of Europe and used as semen donors in an artificial insemination (AI) programme. On 23 February (day 0), slow-release melatonin implants were inserted subcutaneously into rams (n = 8). Control animals (n = 8) received no treatment. In both groups, basic semen parameters (concentration, total motility, fast and slow forward motility, morphology), GnRH-induced testosterone response and basal IGF-I concentration were evaluated on days 0, 47 and 71. No differences were found in concentration of spermatozoa, total motility, and numbers of spermatozoa with fast and slow progressive motility and normal/abnormal morphology between the melatonin-treated and the control group. However, in melatonin-treated animals, basal and GnRH-induced testosterone levels were slightly elevated on day 47 and became significantly higher on day 71 (P < 0.05) as compared to controls. There was no difference in plasma IGF-I levels between the groups. In conclusion, slow-release melatonin applied during the non-breeding season improves testicular testosterone production but does not influence the semen characteristics and the IGF-I level of semen donor Awassi rams used in an AI programme and kept in the temperate continental zone of Europe.