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This study was conducted to investigate the effects of melatonin implantation on basic testicular characteristics and reproductive performance of Kivircik and Charollais rams and ewes during the nonbreeding season. In this study, 8 Kivircik and 6 Charollais rams were used. Rams were implanted with 54 mg melatonin according to the manufacturer's instructions. At melatonin implantation and at ram introduction the reproductive performance and testicular characteristics were evaluated. Throughout the experimental period, rams were permanently kept outdoors under conditions of natural day length and at ambient temperature. The effects of exogenous melatonin treatments on the reproductive performances of rams and ewes, estrus response, pregnancy rate, litter size and twinning rate of ewes were evaluated in all groups. Libido values were significantly higher in Charollais rams compared to Kivircik rams (P<0.001). Testicular volume (TV) was increased in both ram breeds. Scrotal length (SL) was also increased in both Kivircik and Charollais rams (P<0.01). In conclusion, we showed that the treatment of rams with slow release melatonin implants increased scrotal diameters and testicular volumes in both Kivircik and Charollais rams. Furthermore, melatonin implantation improved the reproductive performances of ewes naturally mated with these melatonin implanted rams during non-breeding season.Keywords: ram, melatonin, fertility, non-breeding season RESUMO Esse estudo foi conduzido para investigar os efeitos de implantação de melatonina em características testiculares básicas e desempenho reprodutivo de carneiros Kivircik e Charollais durante a estação não reprodutiva. Nesse estudo, oito carneiros Kivircik e 6 Charollais foram utilizados. Foi implantado 54 mg de melatonina nos cordeiros de acordo com as instruções do produtor. Ao implantar a melatonina e à introdução

Leucemia inhibitory factor (LIF) is involved in various reproductive processes, including sperm development, regulation of ovulation, as well as blastocyst formation, hatching and implantation in embryos. Moreover, LIF has also been shown significantly to enhance the blastocyst formation rates of bovine embryos, a finding that remains controversial. Our purpose was to investigate time-dependent effect of LIF on bovine embryo culture, especially in terms of addition timing. Presumptive zygotes were cultured in five different groups. In this study, 100 ng/ml LIF was added to the culture medium were as follows; control: SOF alone, group A: at day 0 (fertilization day), group B: at day 4 post-insemination (p.i.), group C: at day 4 to 7 (p.i. before vitrification) and group D: at day 8 (p.i. after thawing). Addition of LIF to the culture medium at day 4 significantly increased the percentage of blastocyst rate when compared day 0, day 4 at 6/7 and control group (41.8% versus 24.3%, 19.7%, 34.6%). In conclusion, the addition of LIF only on day 4 (p.i.) to the culture medium was found to be beneficial for bovine embryonic development based on several measures, including blastocysts rate, re-expansion rate and cellular cryotolerance after vitrification.

This study examined the effect of melatonin implantation during the non-breeding season on the reproductive performance of ewes and the testicular dimensions of rams. In seasonally anestrus Kivircik and Charollais ewes and rams were subjected to melatonin. Estrus response was significantly higher in treated than control ewes of both breeds (p<0.001). The pregnancy rate was significantly lower (p<0.001) in the control than in the treated animals. The twinning rate was significantly lower in melatonin implanted Kivircik than Charollais ewes (p<0.05). The testicular dimensions after 42 days of melatonin treatment increased in both breeds. Scrotal length (SL) increased in Kivircik and Charollais rams (p<0.01). The increase in scrotal circumference (SC) was more marked in the Charollais (P<0.01) than in the Kivircik rams. There was a large increase in testicular volume (TV) in both Kivircik (p<0.01) and Charollais (p<0.001) rams. This study shows that melatonin implants can be applied to induce estrus in ewes approximately four months earlier than breeding season. Melatonin implantation in the non-breeding season significantly increased testicular dimensions in Kivircik and Charollais rams thus increasing their reproductive potential.

The aim of the study was to investigate potential use of sequential human embryo culture media in culture of bovine embryos. Bovine oocytes were matured in Tissue Culture for 22 h at 38.5°C and fertilized in modified Tyrode-Albumine-LactatePyruvate medium (mTALP). The putative zygotes were randomly allocated to two embryo culture media groups; (1) Synthetic Oviduct Fluid (SOF) supplemented with fatty-acid free bovine serum albumin (FAF-BSA) (8 mg/ml) and (2) sequential human embryo culture media [Quinn's Advantage Medium-(QAM)] supplemented with FAF-BSA (8 mg/ml). Zygotes were cultured in SOF and sequential QAM for 9 days (5% CO 2 , 5% O 2 , and 90% N 2 ) at 38.5°C. Cleavage (73.3% and 72.2%), morula (37.6% and 33.2%) and blastocysts rates (23.9% and 22.9%) were similar among groups (P>0.05), but the total blastocyst cell number were significantly higher in blastocysts developed in SOF (101.6±4.0) than those in sequential QAM (87.4±3.2) (P<0.05). QAM may be suggested to use in culture as an alternative media in terms of supporting embryo development, but low cell number in blastocysts produced in QAM may suggest a possible low pregnancy rate. Keywords: Bovine, Embryo culture, SOF, QAM, Blastocyst quality Ardışık İnsan Embriyo Kültür Medyumu Sığır Embriyolarınınin vitro Kültüründe Kullanılabilir mi? ÖzetBu çalışmanın amacı, ticari insan embriyo kültür medyumlarının sığır embriyolarının kültüründe kullanılabilirliğinin araştırılmasıdır. Sığır oositleri, TCM-199'da 22 saat süreyle 38,5°C'de maturasyona tabi tutulduktan sonra, mTALP medyumunda fertilize edildiler. Muhtemel zigotlar rastgele 2 gruba ayrıldı; (1) sığır serum albümini (FAF-BSA) (8 mg/ml) ilaveli Sentetik Ovidukt Sıvısı (SOFaa) ve (2) sığır serum albümini (FAF-BSA) (8 mg/ml) ilaveli ardışık Quinn's Advantage Medium (QAM). Muhtemel zigotlar SOFaa ve ardışık QAM medyumlarında 38.5°C'de 9 gün süre ile kültüre edildiler (%5 CO 2 , %5 O 2 ve %90 N 2 ). Yapılan istatistiksel değerlendirme sonucunda; bölünme oranı (%73.3 ve %72.2), morula (%37.6 ve %33.2) ve blastosiste ulaşma oranları yönünden (%23.9 ve %22.9) deneme grupları arasında önemli bir farklılık gözlenmemiştir (P>0.05). Buna karşın total blastosist hücre sayıları yönünden yapılan değerlendirmede, SOFaa medyumu (101.6±4.0) ve QAM medyumunda (87.4±3.2) kültüre edilen blastosistlerin hücre sayıları önemli oranda farklılık göstermiştir (P<0.05). Sonuç olarak, ardışık QAM medyumunun sığır embriyolarının in vitro kültüründe alternatif bir medyum olarak kullanılabileceği, ancak bu medyumdan elde edilen blastosistlerin total hücre sayılarının düşük oluşması sebebiyle beklenilen düzeylerde gebelik oranlarının elde edilmesinde yetersizlik şekillenebileceği düşünülmektedir.

This study aimed to investigate the potentiality of biomodels to be produced as alternative tools to slaughterhouse materials in andrology education. For this purpose, testis biomodels were produced with reference to bull testes. The biomodel production was carried out by the following steps: the preparation of the reference organs, 3D modelling, and processing of data sets and stages. The biomodels and reference testes were compared in terms of morphological parameters and tonicity. As a result of quantitative measurements, the average length in the reference testicles was 145.56 ± 21.3 mm, while the thickness was 61.94 ± 17.2 mm. The average length, thickness, volume and tonicity values of the biomodels showed similarity to the values of the reference testicles (p > .05). However, it was recorded that the average weight of the reference testicles was determined as 368.07 ± 40.3 g, while the average weight of the biomodels was 69.02 ± 3.18 g (p < .01). As a result, it has been shown that testis biomodels can be successfully produced using three‐dimensional technologies. These biomodels are the first examples in the field. We think that the biomodels produced by using innovative technologies should be considered as serious alternatives, which could contribute to the learning processes of students, especially in andrology education.

This study was conducted to determine the effects of different macromolecule sources added to synthetic oviduct fluid (SOF) culture medium supplemented with growth factors on the development of bovine embryos and blastocyst morphology. Zygotes were distributed into 5 treatment groups. Cleavage, morula, and blastocyst rates were evaluated under a stereomicroscope. Trophectoderm (TE) and inner cell mass (ICM) cells were determined by differential staining method. It was found that bovine serum albumin (BSA), either alone or in combination with growth factors, as compared to the control or polyvinyl-alcohol (PVA) resulted in higher embryo yield and faster development during early bovine embryo culture. The quality of bovine embryos, based on the number of blastocyst cells and the ratio of ICM to total blastomeres, was affected by the sources of macromolecules and their combinations with growth factors. Growth factors supplemented to SOFaa media with BSA and PVA significantly increased the number of ICM cells and the ratio of ICM cells to total number of cells. In conclusion, replacing BSA with PVA depressed the blastocyst rate and cell numbers, and the number of blastomeres and ICM and TE cell numbers were affected by both the type of macromolecule and the growth factor supplements.