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Biotechnological methods for improving reproduction on sheep breeding program using laparoscopic artificial inseminations in Debrecen, Hungary
193-200Views:116The aim of this study was to evaluate the results of the LAI method in different types of breeds and seasonal variations. Analysing n=536 LAI in 7 years, there were no significant differences observed in the breed in lambing rates. Although the lambing rate of Prolific Merino (F+) was better than any other breed (45.3%). We found significant differences between breeds of Tzigaia, its pregnancy rate was 19.2%. In the case of prolificacy there were significant differences between breeds: Prolific Merino’s (FF) was the highest (2.38) and, Indigenous Tzigaia’s was the lowest (1.4) from all of them. The obtained results showed that summer inseminations were the most effective in concern of pregnancy rate (49.5%). The results are based on use of the types of semen, showed that using frozen semen was most effective than fresh semen in both parameters, however there were no significant differences. Summarising all tested conditions in our study breeds, seasons and type of semen using LAI the total results of pregnancy rate was 40.3% and the prolificacy was 1.78, respectively. Follow up the out-of-season ovarian, progesterone level of n=36 Prolific Merino were examined and insulin, IGF-1, leptin, T3, and T4 hormones as well, to evaluate the energetic status of the flock. Progesterone analysis showed 43% of examined ewes had a cyclical ovarian function in April and a cyclical ones had good reaction for estrus-induction hormonal treatment. Our results showed that valuable information can be obtained about energy supply from the determination of some metabolic hormones as IGF-1, insulin, leptin.
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Application of laparoscopic artificial insemination in conventional Lacaune sheep farm using frozen-thawed semen
133-138Views:320The complex anatomical structure of the ewe reproductive tract accompanied with low quality of frozen ram semen for artificial insemination, resulted in a challenge with regard to using superior genotypes for reproductive ovine performance. Hence, improved genetics in ovine management has not been efficiently and widely used especially in undeveloped countries. Therefore, intrauterine semen deposition by laparoscopic insemination should be adopted in the current sheep production systems. Thus, this study aimed to assess the pregnancy rate and lambing rate of ewe inseminated by laparoscopic insemination techniques using frozen-thawed semen. The research used imported frozen semen from two rams of the Lacaune breed. Ewes were grouped according to age in years (1, 2 and 4). Before insemination, the semen was examined microscopically for its motility and viability and thereafter the laparoscopic artificial insemination technique was performed to 19 Lacaune breed ewes using frozen-thawed semen. The overall pregnancy and prolificacy rates were 31.57% and 42.10% respectively. Out of 2 ewes in the 1-year age group that were inseminated, only 1 ewe lambed representing 50%. However, from 16 ewes inseminated of four-year age group, 5 ewes lambed representing 31.25%. Significant difference based on age group was not evaluated due disproportionate of the data, (such that the data included 2 ewes in one-year-old age, 1 ewe in 2-year-old age and 16 ewes in 4-year-old age). Based on the ram semen, 33.33% and 30% of the inseminated ewes were pregnant from ram A and ram B semen respectively. However, in the case of prolificacy rate, 44.44% and 40 % of the ewes lambed from using semen of ram A and B, respectively. There was no significant difference (p>0.05) in pregnancy and prolificacy rates based on semen from the two rams. In conclusion, in this research study, ram semen had no significant effect on pregnancy and prolificacy rates using laparoscopic AI on Lacaune sheep. This could be due to the fact that the rams had very good quality semen. Evaluation of ram semen, accompanied with appropriate ewe selection based on age and rightful deposition of semen could lead to better and more consistent results. Overall this could contribute to the successful application of laparoscopic artificial insemination in Lacaune sheep production systems for enhanced productivity.
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Examination of Reproductive Performance of Roe Deer (Capreolus capreolus) in Hungary
33-38Views:138The objective of the research partly is to compare the reproduction performance of the populations living in different regions with regard to some special characteristics (age, condition).
When estimating the age through tooth wear and cementum-layer-counting there was a difference of 0.87 years in favour of the first one (r=0,840; p<0,001). I found cementum layers at 42% of the does in the study after examining the MI teeth.
There was lose connection between the weight (eviscerated, with head and legs) and the KFI (r=0,296; p<0,01), and for further analysis, I used only the KFI as the index for condition.
The regional average KFI varied from 0.24-0.37 in fawns, 0.82-1.73 in does, with individual extremes of 0-4.05. Within the examined regions the highest index belonged to the prime-aged does, while the 1-year-olds had a lower rate, and it was the lowest in the does older than 8 years.
The rate of fertility was between 83,3(ns)-100% as we can see from the presence of the CL. All the examined does were fertile, except in one region, while among the female fawns in two regions I only found three with active ovaries. The average number of CL was 1.5-2.13, and this varied by regions; all in all it was the highest in the 2-7-year-old group (1.96) and in the ones over 8 years (2.00!), while it was lower in the does younger than 1 year (1.90). The high fertility of the does over 8 years is remarkable.
I could examine the number of embryos in two regions during the post-implantation period, and beside 100% fertility I found significant differences among the does, which can be associated with the condition. The ratio of CL carriers and the pregnant does was 100% and 73% in the two regions, the average number of CL were 1.92 and 1.72, while the average embryo number were 1.83 and 1.36 per doe. The difference between the CL and the embryo numbers on the two regions were 5% and 21%. The difference (prenatal loss) is in connection with the age (age class) of the doe. It is possible, however, that in some cases oestrus was not followed by gestation. But in roe deer, owing to the commonly known lack of luteolysis-mechanism (Flint et al., 1994), the regression of the CL of the does that did not get pregnant takes place in December and January, so the CL found in January cannot prove a previous pregnancy, which might have been followed by an abortion.
Although it has to be proven, it seems that the number of the CL (potential progeny) can be associated with the age (r=0,418; p<0,01) and the weight (r=0,312; p<0,01) of the doe, while the embryo number (realised progeny) is influenced by the age of the doe and probably by external factors.
It is essential to continue and extend the research to increase the reliability of the results and their correlation. -
Age of puberty and conception rates of Hungarian Merino, (Merino x Somali) F1 and (Merino x Barbados Blackbelly) F1 ewes
15-19Views:211The aim of our examination was to detect the puberty of the Hungarian Merino and its hairsheep crossbred ewes, and also to determine their average conception rates after having ram exposed in May and June. Hormon diagnostation was used to evaluate the exact date of the very first ovulation. Ultrasound technique was used for checking the conception rates of ewes. The pregnancy detection was applied after a month of the date of taking off the ram.
We evaluated the ages of ewes at puberty. Statistical deviation and standard error were calculated. The results proved the Hungarian Merino x Somali (N=10), ((x ± s) = 173 ± 43) and also the Hungarian Merino x Barbados Blackbelly crossbred genotypes (N=7), ((x ± s) = 186 ± 19) have their puberty much earlier as compared to the fullbred Hungarian Merino ewes (N=10), ((x ± s) = 231 ± 95). We experienced the highest conception rate in the group of the (Hungarian Merino x Somali) F1 ewes after exposing the ram in the „out-of season” period of time.